Metabolic Disorders

Metabolic Disorders-

-Phenylketonuria (PKU)-
-PKU is a disorder that results in a deficiency of phenylalanine hydroxylase (PAH) and if untreated can lead to intellectual disability
-PAH catalyzes the conversion of phenylalanine to tyrosine.  Tetrahydrobiopterin (BH4) is a required cofactor for that activity
-This pathway account for most of the catabolism and is responsible for the disposal of approximately 75 percent of the dietary phenylalanine with the remainder used for protein synthesis
-PKU is mostly caused by a deficiency of PAH
-This results in elevated urine and blood concentrations of phenylalanine and its metabolites
-The mechanism PKU causes intellectual disability is unknown
-Diagnosis is made by high concentrations of serum phenylalanine
-Management includes dietary restrictions of phenylalanine and supplement with medical foods including phenylalanine free protein substitutes
-Some types of PKU patients maybe able to be treated with BH4 the cofactor

Vitamin and Nutritional Deficiencies

Vitamin and Nutritional Deficiencies-

-Vitamin B1 (Thiamine)-
-Thiamine deficiency is associated with 3 disorders:  Beriberi, Wernicke -Korsakoff Syndrome, and Leigh's Syndrome
-Beriberi clinical features can occur cardiomegaly, tachycardia, cyanosis, dyspnea, and vomiting
-Wernicke-Korasakoff Syndrome referes to two separate syndromes Wernicke's Encephalopathy(WE) and Korsakoff Syndrome (KS)
-WE causes nystagmus, ophthalmoplegia, and ataxia, and confusion
-KS is a chronic condition that causes
-Leigh Syndrome presents with subacute necrotizing encephalomyopathy, ataxia, dysarthria, movement disorders, areflexia, muscle atrophy and weakness

-Vitamin B2 (Riboflavin)-
-Riboflavin deficiency presents with sore throat, hyperemia of pharyngeal mucus, edema of mucus membranes, cheilitis, stomatitis, glossitis, normocytic normochromic anemia, and seborrheic dermatitis

-Vitamin B3 (Niacin)-
-Presents as a disorder called Pellagra
-Pellagra tends to be in alcoholics and can be a complication of bariatric surgery
-Pellagra can present as a symmetric hyperpigmented rash, nausea, vomiting, diarrhea, insomnia, anxiety, disorientation, delusions, dementia, and encephalopathy

-Vitamin B5 (Pantothenic Acid)-
-Vitamin B5 deficiency burning, distal paresthesia, and GI distress
-Deficiency is actually rare

-Vitamin B6 (Pyridoxine)-
-Deficiencies of vitamin B6 can include stomatitis, glossitis, cheilosis, irritability, confusion and depression

-Biotin-
-symptoms of biotin deficiency include mental status changes, myalgia, dysesthesias, anorexia, and nausea

-Vitamin C-
-Vitamin C deficiency symptoms include weakness, joint swelling, malaise, arthralgias, edema, depression, neuropathy, and vasomotor instability

-Vitamin B12-
-Vitamin B 12 Deficiency can present because of pernicious anemia.  If there is a lack of intrinsic factor produced by the stomach, it cannot be absorbed into the ileum
-Presents with macrocytic anemia as dose folate deficiency

-Vitamin A-
-Vitamin A Deficiency can present as night blindness, xerosis of the conjunctiva and cornea.  Can also cause growth retardation, and prone to infection

-Vitamin D-
-Vitamin D deficiency presents as deficiency is associated with hypocalcemia, hypophosphatemia, and rickets in children and osteomalacia

-Vitamin E-
-Vitamin E deficiency can be associated with progressive sensory and motor neuropathy, ataxia, retinal detachment, and hemolytic anemia

-Vitamin K-
-Deficiency of Vitamin K results in bleeding diathesis.  May be seen in GI or GU tract, gingiva, lungs, joints, or CNS

-Folate-
-Folic acid deficiency is characterized by hypersegmentation of neutrophils, megaloblastosis, and anemia.  It can also cause growth faltering

-Calcium-
-Calcium deficiency presents with tetany, Chvostek Sign, Trousseau sign and seizures

-Phosphate-
-can cause myopathy, rhabdomyolysis, bone pain, osteomalacia, or rickets

-Magnesium-
-Magnesium deficiency presents with muscle fasciculations, tremors, spasms, and seizures

-Iron-
-Iron deficiency presents with anemia that is microcytic and hypochromic
-Can present with lethargy, pallor, irritability, cardiomegaly, poor feeding, tachypnea, and impaired psychomotor development

-Zinc-
-zinc deficiency presents as poor appetite, diminished taste, hypogonadism, short stature, alopecia, dermatitis, growth failure, cognitive dysfunction, and increased  susceptibility to infection

-Copper-
-Copper deficiency is associated with sideroblastic anemia, neutropenia, failure to thrive, and skeletal abnormalities

-Selenium-
-Selenium deficiency can cause dilated cardiomyopathy with myocardial necrosis and fibrosis.  Condition is called Keshan disease

-Iodine-
-Iodine deficiency can lead to hyperplasia and hypertrophy of the thyroid and can cause hypothyroidism

Infectious and Non-Infectious Diarrhea

Infectious and Non-Infectious Diarrhea-

-Acute diarrhea is defined as less than 14 days of duration
-Persistent diarrhea is defined as more than 14 days of duration
-Chronic diarrhea is more than 30 days in duration

-Most of the causes of acute diarrhea are due to infections with virus and bacteria that are self limited

-Noninfectious etiologies become more common as the course of the diarrhea persists and becomes chronic
-Evaluation of noninfectious etiology should be considered when evaluation of bacterial, viral, or protozoa infections have been rule out

-The major causes of acute diarrhea include viruses (norovirus, rotavirus, adenovirus, astrovirus, and others), bacteria (salmonella, campylbacter, shigella, enterotoxigenic E. Coli, C. Difficile, and others), and protozoa (cryptosporidium, giardia, cyclospora, entamoeba, and others)

-Fever and peritoneal signs should be diagnostic clues of a possible invasive enteric pathogen

-Indications for diagnostic evaluation include:  profuse diarrhea with signs of hypovolemia, passage of many small volume stools containing blood and mucus, bloody diarrhea, temperature of greater than 38.5 degrees C (101.3 degrees F), passage of greater than 6 unformed stools in 24 hours or a duration of illness greater than 48 hours, severe abdominal pain, hospitalized patients or recent use of antibiotics, and systemic illness with diarrhea, especially pregnant women

-Endoscopy may be necessary for determining the difference between infectious diarrhea and inflammatory bowel disease

-Management of acute diarrhea starts with management of hydration and alteration of diet

-Antibiotics should be avoided in patients with Enterohemorrhagic E. Coli

-C. Diff positive patients should have offending antibiotic stopped and consider starting metronidazole or vancomycin

-Listeria may present with diarrhea or systemic illness.  If cultured should be treated with ampicillin and gentamicin or bactrim

-Loperamide can be used for the symptomatic treatment is patients with acute diarrhea who do not have a fever or bloody stool

-Probiotics are an alternative therapy that assist in recolonize the intestine with nonpathogenic flora

-Noninfectious Diarrhea-
-non infectious diarrhea can be caused by carbohydrate malabsorption, maldigestion, malabsorption syndromes, inflammatory bowel disease, ischemic colitis, radiation colitis, neoplasia, laxative abuse, post-cholecystectomy, vasculitis, drugs, poisons, disordered motility, neuroendocrine tumors, Addison's Disease, and Idiopathic secretory diarrhea

-Travelers diarrhea should be treated with antibiotics can be initiated after the diarrhea begins cipro 500 mg BID is given for 1-2 days

Hernia

Hernias-

-Hernias are defined as a protrusion, bulge or projection of an organ or part of an organ through a body wall that normally contains it

-Risk factors for hernias include:  history of prior hernia repair, older age, male sex, caucasian race, chronic cough, chronic constipation, history of AAA, smoking, abdominal wall injury, and family history of hernia

-inguinal hernias are more common then femoral hernias

-groin hernias are classified by location and their etiology (congenital versus acquired)

-Indirect inguinal hernias are the most common type of hernias
-Indirect inguinal hernias protrude at the inguinal ring which is the side at which the spermatic cord in males and round ligament in females exit the abdomen

-Direct Inguinal Hernias protrude medial to the inferior epigastric vessels within Hesselbach's triangle

-Femoral hernias are located inferior to the inguinal ligament and protrude through the femoral ring

-Incarceration refers to trapping of the hernia and its contents within the hernia sac such that reducing them back into the abdomen and pelvis is not feasible
-Reduced lymphatic and venous flow leads to swelling of the incarcerated tissue, which can caused edema and eventually shut of arterial flow
-Shutting off arterial flow to the tissue during this process is referred to as strangulation

-The definitive treatment for all hernias are surgical repair
-Emergent repair is indicated for those who develop complications such as bowel obstruction, bowel perforation, strangulation, or incarceration

-Emergency surgery should be performed within 4-6 hours on hernias that are strangulated hernias

-For uncomplicated hernias repair should be whenever feasible

Rectum

Rectum-

-Anal Fissure-

-An anal fissure is a tear of the anal mucosa
-The goal of treatment is to break the cycle of sphincter spasm and tearing of the anal mucosa to allow for healing of the fissure

-Medical therapy consists of 3 components:  relaxation of the internal sphincter, institution and maintenance of atraumatic passage of stool, and pain  relief

-Most cases this can be accomplished with fiber therapy to keep stools soft and formed and soft, and warm sitz baths following bowel movements to keep the relax the sphincter

-Many topical and injection therapies exist for treatment of this
-Topical Nitroglycerin increases the blood flow and reduces the pressure in the internal anal sphincter which may facilitate healing
-Topical diltazem and bethanechol has also been studied

-Botulinum Toxin has been shown to be helpful in refractory cases
-Oral nifedipine and oral diltazem has been studied and has shown to be beneficial

-Surgical therapy is reserved for those who have failed medical therapy despite adequate medical therapy


-Abscess/Fistula-

-A perianal abscess is an acute phase manifestation of a collection of purulent material that arises from glandular crypts of the anus or rectum

-A perianal fistula represents the chronic phase of suppuration of this perirectal process
-When an abscess is drained or ruptured, an epithelialized track form that connect the abscess in the anus or rectum with the perirectal skin
-Over half of the abscess will develop fistualas
-Other causes of anorectal fistulas include:  Crohn's Disease, Lymphogranuloma Venereum, Radiation Proctitis, Rectal Foreign Bodies, and Actinomycosis
-Surgical treatment is the mainstay of anorectal fistulas

-Perianal abscess traverse distally in the intersphincter groove into the perianal skin where they present as a tender fluctuant mass

-Perianal abscess originates from the infected anal crypt gland

-Patients present with sever pain in the anal or rectal area.  Patients may have fever or malaise

-Imaging studies such as CT scan or MRI is helpful where there is a clinical suspicion of a non palpable abscess

-Treatment involves incision and drainage and antibiotic coverage (Keflex/Bactrim) especially if diabetes or immunosuppression
-Should be cultured


-Fecal Impaction-

-Fecal Impaction is a solid immobile bulk of stool in the rectum
-Should be initially disimpacted manually with manual fragmentation as needed
-After disimpaction is accomplished, an enema with mineral oil will help soften the stool to provide lubrication

-If disimpaction is unsuccessful or partially successful, a water soluble contrast enema such as gastrografin should be administered

-Occasionally fractionation is out of the reach of the finger and will have to be accomplished with sigmoidoscopy


-Hemorrhoids-

-Hemorrhoids are normal vascular structures of the anal canal
-Symptoms of hemorrhoidal disease include anal pruritus, prolapse, bleeding, and pain due to thrombosis

-Hemorrhoids arise from a plexus called a cushion of dilated arteriovenous channels and connective tissue from the superior and inferior hemorrhoidal veins
-The hemorrhoids are located in the mucosal layer in the lower rectum and may be classified internal or external if they are above are below the dentate line.
-The hemorrhoids that above the dentate line are internal hemorrhoids and do not have any sensory innervation.
-Hemorrhoids that below the dentate line do have sensory input and are external hemorrhoids

-Development of hemorrhoids have been associated with advancing age, diarrhea, pregnancy, pelvic tumors, prolonged sitting, straining, and chronic constipation

-Adding fiber to a diet may be beneficial for patients with bleeding from hemorrhoids
-Irritation and pruritus can be treated with topical analgesic creams and hydrocortisone creams/suppositories
-Thrombosed hemorrhoids may need surgical evacuation
-Thrombosed hemorrhoids can be attempted to treated with topical and oral analgesics, stool softeners, and sitz baths

-External hemorrhoids, with the exception of thrombosis, usually do not require surgical therapy
-Some surgeons recommend excision to not to endure recurrent thrombosis
-Failure of medical therapy can be an indication for excision of external hemorrhoids also

-Internal hemorrhoids can be treated with rubber band ligation, infrared coagulation, bicap, laser photocoagulation, sclerotherapy, and cryosurgery


-Rectal Neoplasms-

-The goal of treatment of rectal cancer is surgical resection
-Radiation therapy and chemotherapy is often given preoperative to help improve cure rates

-Locally advanced disease is defined as a lesion that cannot be resected without a  high likelihood of leaving microscopic or gross residual disease at the site because of tumor adherence of fixation
-A locally advance lesion can arrange from a tethered or marginally resectable tumor to a fixed cancer that direct invades adjacent structures

-Pretreatment evaluation rests on its physical exam inaction and CT or MRI appearance
-Majority of rectal cancer is adenocarcinoma

-The goal of pretreatment is to shrink the tumor down enough where it can be resected

Small Intestine/Colon

Small Intestine/Colon-

-Appendicitis-

-Appendicitis is the most common cause of surgical abdomen in the pediatric age group
-presents as periumbilical diffuse abdominal pain localizing to the right lower quadrant with nausea and vomiting and fever
-The diagnosis is made clinically, labs are of limited value.  WBC may be moldy elevated.  Pyuria and ketonuria are limited diagnostic help

-Physical exam reveals tenderness at McBurney's point.
-Psoas- maneuver involving flexing the leg against resistance to exacerbate retro-cecal appendix
-Obturator - maneuver involving abducting the hip and flexing hip to exacerbate retro-cecal appendix

-CT scans of abdomen and Pelvis or ultrasound can be used to diagnose appendicitis

-Perforation is more likely to occur in children because the flimsy omentum and delay the diagnosis

-If the diagnosis is in question, and clinical picture is consistent with appendicitis, the patient should be observed


-Celiac Disease-

-Celiac disease is characterized by mucosal inflammation, villous atrophy, and crypt hyperplasia that occurs with exposure to gluten diets and improve when gluten is improved
-Testing for celiac disease should be considered for those with clinical manifestations that may be representative of celiac disease
-Clinical manifestations of celiac disease include:  recurrent diarrhea, malabsorption, weight loss, abdominal dissension, bloating, iron deficiency anemia, folate deficiency, vitamin B12 deficiency, persistent elevation of serum transaminases, short stature, delayed puberty, recurrent fetal loss, low birth weight infants, infertility, aphthous stomatitis, dental enamel hypoplasia, idiopathic peripheral neuropathy, cerebellar ataxia, recurrent migraine headaches, first degree relatives with diagnosis, and those with Down's Syndrome

-Immunoglobulin A (IgA) anti-tissue transglutaminase (TTG) antibody is the single preferred test for detection of celiac disease in individuals over the age of two years
-When there is a high likelihood of celiac disease the total IgA should be measured
-Can also measure both IgA and IgG based testing such as IgG deaminated gliadin peptides (DGP's) in patients with a high probability of celiac disease.
-In patients that have low IgA or IgA deficiency is identified, IgG based testing (IgG DGP's and IgG TTG) should be performed

-Patients with positive serology should undergo a small bowel biopsy to confirm the diagnosis of celiac disease

-There are many non gastrointestinal manifestations of celiac disease and they include:  headache, peripheral neuropathy, ataxia, depression, anxiety, epilepsy, arthritis, iron deficiency, metabolic bone disease, hyposplenism, kidney disease, and idiopathic pulmonary hemosiderosis

-Mainstay of treatment is going on a gluten free diet


-Constipation-

-Constipation is defined as stool frequency of less than three times per week
-Secondary causes of constipation include:  obstructing lesions of the GI tract, diabetes mellitus, hypothyroidism, anorexia nervosa.
-Hirschsprung disease and functional outlet disorder can lead to impairment of defecation
-Megacolon and megarectum patients snake a small percentage with constipation

-Lab evaluation, endoscopic evaluation, and radiologic studies should be performed on selected individuals with chronic constipation and failure response to traditional therapy.

-After evaluation for structural problems, metabolic evaluation, and baseline labs, there should be a trial of fiber and laxatives
-if there is a failure of this therapy, there should be anorectal manometry and a balloon expulsion test

-Bulk forming laxatives include Metamucil, Citrucel, Fiber Con, and Benefiber
-Surfactants such as Colace are intended to lower the surface tension of stool
-Osmotic agents such as GoLytely, Lactulose, and Magnesium Citrate cause intestinal water secretion and thereby increases stool frequency
-Stimulant laxatives such as dulcolax and senna primarily exert their effects by alteration of electrolyte transport by intestinal mucosa


-Diverticular Disease-

-Diverticulum is a sac like protrusion from the colonic wall
-Diverticulosis is the presence of diverticula
-Diverticular disease is clinically significant and symptomatic diverticulosis due to diverticular bleeding, diverticulitis, segmental colitis, associated with diverticula, or symptomatic uncomplicated diverticular disease

-Diverticular bleeding is painless hematochezia due to weakness of the vasa recta associated with diverticulum
-Diverticulitis is defined as inflammation of the diverticulum.  Can be complicated by abscess, fistula, bowel obstruction, or free perforation

-Studies have shown low dietary fiber predisposes to the development of diverticular disease
-Studies have also shown an increase in diverticular disease high fat and red meat

-Seeds and its are not associated with an increase in risk for diverticulosis, diverticulitis, or diverticular bleeding

-Obesity and smoking has been associated with an increase in risk of both diverticulitis and diverticular bleeding

-Diverticula develop at well defined points of weakness, which correspond to where the vasa recta penetrate through the circular muscle layer of the colon

-Uncomplicated diverticulitis is diverticulitis without inflammatory complications such as perforation or abscess.  Up to 30 percent will require surgical intervention

-Complicated diverticulitis refers to the presence of perforation, obstruction, abscess, or fistula.  Nearly all these patents will require surgery

-Usual outpatient management includes Cipro 500 mg BID plus Flagyl 500 mg TID or Augmentin BID for 10-14 days
-For patients that are intolerant to flagyl, Clindamycin is acceptable alternative
-Outpatient diet recommendations are for a clear liquid diet

-Patients with complicated diverticulitis should be treated with IV antibiotics for gram negative and anaerobic pathogens
-Recommended IV antibiotics for complicated diverticulitis include Unaysn or Zosyn/ or Rocephin plus Flagyl

-Complications of diverticulitis include:  peritonitis, obstruction, abscess, perforation, and fistulas

-Indications for operative management include:  sepsis, diffuse peritonitis, treat a fistula, or abscess

-Goals of surgery include to remove septic focus by resection, to treat a fistula, and to restore the bowel continuity

-Resection of the diverticulosis is considered curative for diverticulosis


-Inflammatory Bowel Disease (IBD)-

-Inflammatory Bowel Disease refers to primarily ulcerative colitis (UC) and Crohn's disease
-Ulcerative colitis is an inflammatory disorder limited to the colon
-Etiology of UC is unknown
-UC involves inflammation of the mucosal surface, and is not transmural
-UC always begins at the rectum
-UC presents with blood diarrhea, abdominal cramping, and stools often have mucus with the blood
-UC may also present with anorexia and weight loss
-Toxic megacolon is a rare complication of UC

-Patients with UC present with diarrhea and maybe blood or mucus,  colicky abdominal pain, urgency, tenesmus, and incontinence.  May have some weight loss.  These symptoms are usually gradual and presents over several weeks.

-Extracolonic manifestations of UC include peripheral arthritis, erythema nodosum, scleritis, iritis, conjunctivitis, primary sclerosing cholangitis, venous and arterial embolism, airway inflammation, and aphthous ulcers

-Can get strictures as a complication of UC

-Mild UC management includes sulfasalazine and systemic steroids
-More severe UC should be admitted with NG decompression, ACTH if not on steroids, high dose parenteral steroids, H2 blockers and IV fluids
-Cyclosporin and Infliximab can induce remission in patients with fulminant UC

-Colectomy is curative for patients with UC and is an option for those who fail medical treatment

-Crohn's Disease (CD) is characterized by transmural inflammation of the GI tract.
-CD can occur anywhere from the mouth to the anus
-Most common part of alimentary canal affected is the terminal ileum

-Clinical symptoms of CD are:  fatigue, diarrhea, abdominal pain, weight loss, fever, may have diarrhea with or without bleeding

-Complications of CD include phlegmon and abscess, perineal disease such as fissures, malabsorption, aphthous ulcers, odynophagia, dysphagia, gallstones

-Manifestations outside of the GI tract include:  arthritis, uveitis, iritis, episcleritis, erythema nodosum, primary sclerosing cholangitis, secondary amyloidosis, venous and arterial embolism, renal stones, bone loss and osteoporosis, Vitamin B12 deficiency, and pulmonary development

-diagnosis of CD and UC are definitively made of tissue biopsy during endoscopy

-Treatment of CD includes sulfasalazine, mesalamine, glucocorticoids, immunomodulators (azathioprine, methotrexate), and biologic therapies (infliximab, and adalimumab)


-Intussusception-

-Intussusception refers to the invagination of a part of the intestine onto itself
-Intussusception is the most common abdominal emergency in early childhood, especially those less than 2 years of age
-The majority of cases intussusception in children are idiopathic

-Intussusception occurs most often near the ileocecal junction.

-The lead point is a lesion or variation in the intestine that is trapped by peristalsis and dragged into the distal segment of the intestine

-Meckel's diverticulum, polyp, tumor, hematoma, or vascular malformation can act as the lead point

-Patients typically develop intermittent crampy, severe progressive abdominal pain,  accompanied by inconsolable crying and drawing the legs towards the abdomen.
-Vomiting may follow episodes of abdominal pain
-Between the episodes the child may be pain free
-70 percent of the stools will contain gross blood or occult blood, may be a mixture of blood and mucus (currant jelly)
-Barium enema can be diagnostic and therapeutic
-Surgical resection may be needed if this fails
-Ultrasound or CT scan of Abdomen and Pelvis can diagnose intussusception also


-Irritable Bowel Syndrome-

-Irritable Bowel Syndrome (IBS) is a GI syndrome defined by chronic abdominal pain and altered bowel habits in the absence of any organic cause
-It is the most common diagnosed GI condition
-IBS is more common in women than men

-Most common presenting symptoms of IBS are chronic abdominal pain, and altered bowel habits

-The chronic abdominal pain is a variable intensity and cramping with periodic exacerbations

-Emotional stress, eating, may exacerbate the pain while defecation usually provides relief

-Things that should increase the suspicion for organic disease causing symptoms include:  anorexia, weight loss, rectal bleeding, nocturnal pain, laboratory abnormalities,  and malnutrition

-Patients may have diarrhea or constipation both

-The predominate symptom should be treated

-IBS is a diagnosis of exclusion.  Patients need to have endoscopy, lab evaluation, or imaging to help rule out organic cause


-Ischemic Bowel Disease-

-Ischemic bowel disease is caused by a reduction of intestinal blood flow secondary to occlusion, vasospasm, and/or hypoperfusion
-Common sequelae of ischemic bowel include sepsis, bowel infarction, and death

-Acute ischemic bowel refers to sudden onset of intestinal hypoperfusion, which is due to occlusive or non occlusive arterial or venous flow

-Chronic ischemic bowel (intestinal angina) refers to episodic or constant intestinal hypoperfusion which develops with patients with atherosclerotic disease and is strongly associated with eating meals

-Clinical presentation is having a rapid onset of periumbilical pain, which is often out of proportion to physical findings.  Nausea and vomiting are usually present

-Risk factors for ischemic bowel include: atrial fibrillation, CHF, peripheral vascular disease, or hypercoagulable state

-Diagnosis is made either with a dynamic CT scan or mesenteric angiography

-Labs usually reveal leukocytosis and metabolic acidosis

-Initial management should include hemodynamic monitoring and support, correction metabolic acidosis, broad spectrum antibiotics, and NG tube for gastric decompression

-Systemic anticoagulation should be administered

-Surgical laparotomy and embolectomy is the traditional treatment for arterial occlusion


-Lactose Intolerance-

-Clinical symptoms of lactose intolerance include diarrhea, abdominal pain, and flatulence after eating milk or milk containing products
-These symptoms are attributed to low lactase levels which may be due to mucosal injury or much more commonly reduced genetic expression of an enzyme

-Lactose digestion is the rate limited step in the overall process of its absorption.
-Defects in the digestion result in severe diarrhea after intake
-Lactose not absorbed by the small intestine is passed to the colon.  In the colon is it is salvaged by converting them to short chained fatty acids

-Major primary causes of lactose malabsorption include:  racial or ethnic, developmental, congenital lactase deficiency
-Major secondary causes of lactose malabsorption include:  bacterial overgrowth, infectious enteritis, giardiasis, mucosal injury (celiac disease, IBD, or drug/radiation induced enteritis

-Diagnosis of lactose malabsorption is made by a lactose absorption test or lactose breath hydrogen test

-Treatment of lactose intolerance includes: decreased dietary intake of lactose, substitution of nutrient sources to maintain energy and protein intake, administer enzyme substitute, and maintenance of calcium and vitamin D intake


-Neoplasms-

-Small intestine tumors are difficult to diagnose because of their rarity and the nonspecific symptoms that they cause

-There are benign (adenoma, leiomyoma, and lipoma)  and malignant (adenocarcinoma, carcinoid, lymphoma, and sarcomas)tumors of the small intestine 

-Adenocarcinomas are usually between 25-40 percent of small bowel cancers
-Adenocarcinomas can have predisposing factors such as Crohn's Disease and those who have had colorectal cancer

-Carcinoid tumors are well differentiated neuroendocrine tumors that have an indolent disease course.  Symptoms generally come from mass effects from the primary or metastatic tumors from production of bioactive amines

-Lymphoma may arise as a primary small intestine neoplasm as a component of systemic disease with GI involvement.  Must have no peripheral or mediastinal lymphadenopathy, a normal WBC and differential, tumor involvement must be predominately in the GI tract, and no evidence of spleen or hepatic involvement
-Risk factors for Lymphoma include Autoimmune disease, AIDS, Long Term Immunosuppressive Therapy, Crohn's Disease, Radiation Therapy, or Nodular Lymphoid Hyperplasia

-Sarcomas are malignant mesenchymal tumors that represent about 10 percent of small intestine tumors
-Most common intestinal sarcoma is called a gastrointestinal stromal tumor (GIST)

-Adenomas such as villous and tubular adenomas are benign but have malignant potential
-A Brunner's Gland Adenoma is a rare neoplasm caused by hyperplasia of exocrine glands

-Leiomyomas are single, firm, gray or white well defined masses that arise in the submucosal layer of the wall of the intestine.  They are rare benign lesions

-Lipomas are the second most common benign tumor in the small intestine.  They occur mostly in the ileum and duodenum

-The vast majority of colorectal cancers are adenocarcinomas.

-Appendix cancer is rare

-Other tumors of the large bowel include Kaposi Sarcoma, lymphomas, and carcinoid tumors

-Tumors are staged in the TMN system

-Ultimate goal eventually is surgical resection

-The tumor marker CEA (Carcinoembryonic Antigen) should be routinely measured preoperatively in patients undergoing potentially curative resections for colorectal cancer


-Obstruction-

-bowel obstruction occurs when the normal flow of intestinal contents are disrupted
-obstruction can be functional due to intestinal physiology or due to a mechanical obstruction
-Severe small bowel obstruction leads to bowel dilation and retention of fluid within the lumen to obstruction, while the distal obstruction, as lumina contents pass the bowel compresses
-If bowel dilation is excessive, strangulation occurs leading to necrosis or perforation

-Most common causes of small bowel obstruction are post op adhesions and hernias
-SBO can be due to tumor, stricture, intramural hematoma, gallstones, foreign bodies, and intussusception

-Risk factors for SBO include:  prior abdominal or pelvic surgery, abdominal wall or groin hernia, intestinal inflammation, neoplasm, prior radiation, or history of FB ingestion

-Clinical symptoms of SBO include abdominal pain, nausea, vomiting, and abdominal dissension
-Will have hypoactive bowel sounds and diffusely tender distended abdomen

-3 view abdomen or CT scan of Abdomen and Pelvis can help confirm the diagnosis

-Treatment is IV hydration, NPO, NG decompression, analgesics, and antiemetics
-Patient may need surgical intervention if it does not resolve with medical therapy

-Large bowel obstruction has similar presentation and treatment but its main causes is neoplasm


-Polyps-

-Non neoplastic polyps can be grouped into several categories:  hyperplastic, mucosal, inflammatory pseudopolyps, and submucosal (some which may be neoplastic-lipomatous and leiomyoma)

-Hyperplastic polyps appear to advance to more advanced lesions and cancer

-Inflammatory pseudopolyps occur with inflammatory bowel disease.  

-Mucosal polyps are small and clinical insignificant

-Submucosal polyps include lymphoid aggregates, lipomas, leiomyomas, pneumatosis cystoid intestinalis, hemangiomas, fibromas, carcinoids, and metastatic lesions

-Hamartomas polyps are polyps that are made of tissue elements normally found at the site.  Most of the time non neoplastic but some can develop dysplasia and lead to colorectal cancer

-common neoplastic colonic polyps include serrated polyps and adenomatous polyps

-Most studies suggest the development of cancer from adenomatous polyps is 7-10 years

-Treatment of these polyps is endoscopic removal

-Surveillance is recommended every 10 years after negative colonoscopy or 3-5 years after polyp removed

-Recommended colorectal screening is starting at age 50 or 10 years younger than a first degree relative with colorectal cancer 

-Toxic Megacolon-

-Toxic Megacolon is a potentially lethal complication of inflammatory bowel disease or infectious colitis
-It is characterized by total or segmental non obstructive colonic dilation plus system toxicity

-Colonic dilation is also observed in patients with congenital megacolon (Hirschsprung's Disease), idiopathic or acquired megacolon occurring with chronic constipation, and intestinal pseudo obstruction, a manifestation of diffuse GI dysmotility of various causes

-Etiology of toxic megacolon is mostly IBD, but also can occur with infectious colitis, volvulus, diverticulitis, ischemic colitis, and obstructive colon cancer

-One possible pathogenic mechanism is that mucosal inflammation leads to release of inflammatory mediators and bacterial products, increased nitrous oxide synthase, gene ratio of excessive nitric oxide and colonic dilation

-Signs and symptoms include: severe blood diarrhea, malaise, and abdominal pain and dissension

-The transverse colon is dilated greater than 6 cm and up to 15 cm on supine films

-CT scan of Abdomen and Pelvis is recommended

-The main goal of treatment is to reduce the severity of the colitis and restore normal colon motility and decrease the likelihood of perforation.  Surgical consult should be obtained on admission up to 50 percent of patients may fail medical therapy and require surgical treatment

Pancreas

Pancreas-

-Acute/Chronic Pancreatitis-

-characterized by inflammation of the pancreas.  Can be acute or chronic
-causes auto digestion of pancreatic and peri-pancreatic tissues from the continuing release of digestive enzymes and vasoconstrictive substances

-most common etiologies gallbladder disease and alcohol (85-90%) of cases
-other etiologies include trauma, viral infections (mumps, cocksackie), hypercalcemia, hypertriglyceridemia, DKA, azathioprine, estrogen, thiazides, valproate, tetracycline, scorpion stings, methanol ingestion, SLE, periarteritis nodosa, and idiopathic

-signs and symptoms:  abdominal pain, nausea, vomiting, low grade fever, tachycardia, abdominal distention, and crackle in the bases
-Cullen's Sign-echymotic discoloration in the periumbilical region with severe pancreatitis
-Grey Turner's Sign-ecyhmotic discoloration in the flank with severe pancreatitis

-Labs reveal elevated lipase (more sensitive) and amylase (60-80% sensitive)
-Amylase and lipase considered specific if three times normal value
-May have mildly elevated WBC's, hypocalcemia, mild increase in bilirubin, decreased albumin, increased BUN, decreased HCO3

-Radiographs may find pancreatic calcifications in chronic disease, localized ileus, left pleural effusion/atelectasis

-Treatment is IV hydration, NPO, anti emetics, and analgesics
-Need to rest the pancreas

-Complications include: necrotizing pancreatitis, pancreatic pseudocyst, pancreatic abscess, exocrine insufficiency, and diabetes from endocrine insufficiency


-Ranson Criteria-
-Initial Criteria
Age >55
WBC > 16,000
Glucose >200
LDH > 350
AST > 250

-Criteria after 48 hours
Decrease in Hct >10%
Increase in BUN > 5
Calcium < 8.0
PaO2 < 60
BE > 4
Fluid Sequestration > 6 Liters

-Number of Criteria Present=
0-2=1% mortality
3-4=16% mortality
5-6=40% mortality
>7=100% mortality

-Chronic Pancreatitis presents as chronic unrelenting pain with flares over many years.
-Chronic Pancreatitis "burns out" over time and endocrine and exocrine dysfunction can develop
-Recommended cessation of alcohol intake, small meals, good hydration, and cessation of smoking
-Pancreatic enzyme supplements suppress exocrine secretion and relieve some pain in some patients
-Patients may need pseudocyst drainage if symptomatic


-Neoplasms-

-Pancreatic cancer is the forth in the cancers causing death in the US

-Pancreatic Ductal Adenocarcinoma- makes up about 85 percent of pancreatic cancers
-Diagnosis requires biopsy or surgical resection.  Has high mortality rate
-usually spreads to adjacent structures such as the duodenum, portal vein, and mesenteric vessels

-Pancreatic Intraepithelial Neoplasia (PanIN) is a small intraductal non invasive lesion that is formed by metaplasia and increased proliferation of the epithelium
-most pancreatic adenocarcinomas arise from PanIN
-considered to by a precursor to invasive ductal adenocarcinoma

-Intraductal Papillary Mucinous Neoplasms (IPMN) are cystic neoplasms derived from the pancreatic ducts
-Patients with IPMN can present with current episodes of pancreatitis
-Diagnosis is suspected when the papilla of Vater has thick mucus extruding from it
-Malignant potential is determined by the histology rather than its location

-Mucinous Cystic Neoplasms (MCN) are sharply demarcated cystic masses with a thick fibrous wall that occur in the body or tail of the pancreas

-Serous Cystadenomas are benign neoplasms

-Solid Pseudopapillary Neoplasms- begin as solid neoplasm that become cystic as they grow large and the cells become so far removed their blood supply and undergo apoptosis or necrosis
-Most of the time these lesions are cleared by resection but metastasis has been reported in a small percentage

-Acinar Cell Carcinoma-rare malignant neoplasms that are solid but sometimes cystic.  Prognosis is better than ductal adenocarcinomas

-Pancreatoblastomas-malignant lesions presumed to be of stem cell origin.  There is less of mortality rate for these lesions than with ductal adenocarcinomas

Liver

Liver-

-Acute/Chronic Hepatitis-

-Hepatitis is inflammation of the liver

-Types/Causes of Hepatitis:  viral infections, bacterial infections, fungal infections, parasitic infections, toxic exposure, side effect of medication, immunologic

-4 phases of infection:  viral replication, prodromal phase, icteric phase, and convalescent phase

-physical exam is dependent on the type of hepatitis and time of presentation

-possible physical exam findings include:  low grade fever, vomiting, dehydration, icterus, urticarial or petechial rashes, enlarged liver and RUQ tenderness

-Hepatitis A- Picromavirus which is an RNA virus

-Hepatitis A is spread by oral fecal route

-Diagnosis elevated IgM acutely and IgG chronically

-Treatment of Hepatitis A is symptomatic 

-Hepatitis A has a vaccine 

-Hepatitis B is a DNA virus

-transmission is by serum, saliva and semen

-high risk groups are IV drug users, homosexual males, hemodialysis patients, heterosexuals with multiple partners,  and health care workers

-chronic carrier state of hepatitis B is at increased risk for hepatocellular carcinoma

-HbsAg s the first sign of Hepatitis B before clinical disease 

-Anti-HBs appears after HbsAg is cleared

-Anti-HBc core antibody is the earliest detectable antibody to infection in most patients

-HbeAg e antigen is indicative of high infectivity

-typically have RUQ pain, fatigue, elevated LFT's, atypical lymphocytes, and 15% serum sickness

-treatment is supportive care.  Patients with coagulopathy, dehydration, and encephalopathy need to be hospitalized

-HBIG (Hepatitis B Immunoglobulin) should be given post exposure plus the Hepatitis B vaccine

-Hepatitis B vaccine is given 3 stages

-Hepatitis C virus is a single stranded RNA virus

-90% of Hepatitis C patients are post transfusion patients

-can be transmitted parenterally, perinatally, and sexually

-more patients have Hepatitis C then HIV

-incubation period 50 days

-chronic carriers 50-70% of the time

-treatment is supportive, can give interferon or PEG interferon 15-60% response rate

-there is no vaccine or immunoglobulin that is effective

-Hepatitis D (also called Delta Hepatitis)

-it is a defective RNA virus that requires hepatitis B for replication

-transmission is similar to hepatitis B

-no effective vaccine or immunoglobulin is effective

-One third with concurrent infections will develop fulminant hepatitis

-Hepatitis E is Enteric RNA Virus

-a major cause of hepatitis endemic to Asia

-Transmitted oral fecal route

-No vaccine or immunoglobulin is helpful

-Hepatitis F is enteric ally transmitted

-No vaccine or immunoglobulin is helpful

-Hepatitis G is a severe sporadic hepatitis 

-it has been recently isolated

-CMV (Cytomegalovirus) Hepatitis is a latent infection that reactivated during immunosuppression

-most common opportunistic viral infection in patients with liver transplant

-Treatment of CMV hepatitis is Grancyclovir 

-Epstein Barr (EBV) Hepatitis caused by mononucleosis

-Only 5 percent of patients with mononucleosis will develop jaundice

-Other viral causes of hepatitis include herpes simplex and varicella zoster

-Toxic Induced Hepatitis examples include:  Halothane, INH, Thorazine, Dilantin, Tylenol, Mushrooms, oral contraceptives, erythromycin, esolate, chlorpromazine

-Alcoholic Hepatitis may develop in 10 percent of alcoholics and lead to hepatic failure

-Seen in chronic alcoholics not just new exposures to alcohol

-Symptoms of alcoholic hepatitis include:  RUQ pain, leukocytosis, hypoglycemia, anemia, AST twice ALT, elevated INR, gynecomastia, spider angiomas, muscle waisting, ascites, and palmer erythema

-treatment is supportive

-want to supplement thiamine and glucose and Mg when necessary

-want a high calorie, vitamin supplemental diet with low protein content

-Autoimmune Hepatitis is a progressive inflammatory disorder of the liver

-More common in young women and girls

-serum gamma globulin levels are twice normal, positive ANA and or anti smooth muscle antibodies

-Treatment of autoimmune hepatitis is with steroids and immuran

-liver transplant is a possible therapy

-Chronic Hepatitis B and C patients need a liver transplant for end stage liver disease

-MELD score will help evaluate their mortality rate

-the majority of patients with acute hepatitis C do not spontaneous clear and thus develop chronic hepatitis

-Cirrhosis-

-cirrhosis is a late stage of progressive hepatic fibrosis characterized by distortion of the hepatic tissue and formation of regenerative nodules

-it is irreversible in the late stages, and only treatment is liver transplant

-most common causes of cirrhosis in the US are alcoholic liver disease and hepatitis C

-the most common causes of cirrhosis are chronic viral hepatitis (B and C), alcoholic liver disease, hemochromatosis, and non alcoholic fatty liver disease

-other causes of cirrhosis include autoimmune hepatitis, primary and secondary biliary cirrhosis, primary sclerosing cholangitis, medications (methotrexate, INH), Wilson disease, alpha 1 anti-trypsin deficiency, idiopathic adulthood ductopenia, granulomatous liver disease, idiopathic portal fibrosis, infections, right heart failure, and venous occlusive disease

-symptoms or cirrhosis include anorexia, weight loss, weakness, and fatigue

-maybe asymptomatic

-patients with decompensated cirrhosis may have jaundice, pruritus, and signs of upper GI bleeding

-as cirrhosis progresses, patients can have a decrease in the mean arterial pressure

-patients with cirrhosis may have parotid gland enlargement, gynecomastia, ascites, hepatomegaly, splenomegaly, testicular atrophy, clubbing, and asterixis 

-AST and ALT are usually moderately elevated in cirrhosis

-alkaline phosphatase is usually elevated in cirrhosis

-GGT levels usually correlate with alkaline phosphatase levels with cirrhosis

-bilirubin levels may be normal in compensated cirrhosis

-albumin levels usually fall

-INR levels generally increase because these proteins are synthesized in the liver and advance cirrhosis there are less of them

-usually have hyponatremia because of ascites and the inability to excrete free water

-pancytopenia is common with cirrhosis 

-Liver biopsy is required to definitively confirm cirrhosis

-major complications of cirrhosis include:  variceal hemorrhage, ascites, spontaneous bacterial peritonitis, hepatic encephalopathy, hepatocellular carcinoma, hepatorenal syndrome, and hepatopulmonary syndrome

-major goals of managing patients with cirrhosis include showing or reversing progression of liver disease, preventing superimposed insults to liver, discontinuing hepatotoxic meds, managing symptoms and lab abnormalities, preventing identifying and treating complications of cirrhosis, and determining the appropriateness and timing of liver transplant

-Neoplasms-

-Common benign liver lesions include:  hepatic hemangiomas, focal nodular hyperplasia, hepatic adenoma, idiopathic portal hypertension, and regenerative nodules

-Common malignant liver lesions include hepatocellular carcinoma, cholangiocarcinoma, and metastatic disease

-Hepatic hemangiomas are called this because of the cavernous vascular space occupied and they are the most common mesenchymal hepatic tumors.  Cause symptoms when larger than 4 cm

-Focal Nodular Hyperplasia is benign liver tumor that is hyperplastic response to an anomalous artery

-Hepatic adenomas is a benign epithelial liver lesion that occurs in a non cirrhosis liver.  The majority of patients have used oral contraceptives for 2 years before diagnosis. These have a small risk of neoplastic transformation

-Idiopathic Non Cirrhosis Portal Hypertension is a condition where there is multiple foci of proliferating hepatocytes forming nodules throughout the liver.  

-Regenerative nodules are nodules that form in response to hepatic injury.  Usually seen with cirrhosis

-Hepatocellular Carcinoma is a primary liver malignancy that occurs in the setting of chronic liver disease such as chronic hepatitis B or cirrhosis

-Cholangiocarcinoma is a malignancy of the bile ducts.  Risk factors include primary sclerosing cholangitis and choledochal cysts

-Metastatic liver tumors are the most common form of malignant hepatic neoplasms

-CT scan or MRI is usually the imaging studies of choice

-Surgical resection is recommended for lesions that are symptomatic or if hepatocellular carcinoma cannot be excluded on lab results, imaging or by fine needle aspirate

Gallbladder

Gallbladder-

-Acute/Chronic Cholecystitis-

-usually occurs as a complication of gallstone disease
-cholecystitis means inflammation of the gall bladder

-Acute cholecystitis is a syndrome of RUQ pain, fever, and leukocytosis associated with gallbladder inflammation that is mostly related to gallstone disease

-Acalculous Cholecystitis is identical to acute cholecystitis but does not involve gallstones

-Chronic cholecystitis describes chronic inflammatory cell infiltration of the gallbladder seen on pathology
-mostly seen in the presence of gallstones thought to be seen as a result of mechanical irritation of chronic attacks

-Acute cholecystitis occurs in the setting of cystic duct obstruction.  An additional irritant is needed to cause gallbladder inflammation.

-Clinical symptoms of acute cholecystitis include prolonged (over 4-6 hrs) of severe RUQ  or epigastric pain, fever, abdominal guarding, leukocytosis and a positive Murphy's sign
-Pain may radiate to the patients back or right shoulder
-may have associated nausea, vomiting, and anorexia
-patients are usually ill appearing, febrile, and tachycardic

-Patients typically have leukocytosis with increased number of bands, elevated total bilirubin and alkaline phosphatase

-Mirizzi Syndrome (a gallstone impacted in the distal cystic duct causing extrinsic compression of the common bile duct)

-Emphysematous Cholecystitis has a mild to moderate unconjugated hyperbilrubinemia that may be present because of hemolysis induced by a clostridial infection

-Confirmation of the diagnosis of cholecystitis requires demonstration of the gallbladder wall thickening or edema on an imaging study (usually ultrasound)

-Complications of cholecystitis include gangrene, perforation, cholecystoenteric fistula, gallstone ileus, or emphysematous cholecystitis

-Patients with acute cholecystitis should be admitted to the hospital and receive IV hydration, opioid analgesics and have electrolyte imbalances corrected
-Acute cholecystitis is an inflammatory process, secondary infection of the gallbladder can occur as a result of the cystic duct obstruction and bile stasis.
-It is not clear that antibiotics are required for the treatment of acute cholecystitis that is uncomplicated.  It doses not lower the risk of abscess or empyema but does lower the rate of bacteria and wound infection

-Patients definitively need their gallbladder removed at some point.


-Cholangitis-

-acute cholangitis is characterized by fever, jaundice, and abdominal pain
-acute cholangitis develops as a result of stasis and infection of the biliary tract
-acute cholangitis is referred to as ascending cholangitis

-acute cholangitis is caused by bacterial infection in a patient with biliary obstruction or stasis
-the organisms ascend through the duodenum via hematogenous spread from the portal vein
-causes of biliary obstruction include benign stenosis, malignancy, stent placement, and biliary stones
-E.Coli is the most common bacteria involved.  Enterbacter, Klebsiella,  Bacteroides, Clostridia and Enterococcus are other organisms involved

-Clinical presentation can involve Charcot's Triad:  fever, abdominal pain, and jaundice
-Reynold's Pentad includes Charcot Triad plus hypotension and confusion that can see with supprative cholangitis

-Labs reveal elevated WBC, elevated alkaline phosphatase, GGT, and bilirubin

-Tokyo Guidelines for diagnosis of acute cholangitis include (two or more of the following):  history of biliary disease, fever or chills, jaundice, and abdominal pain

-Diagnosis is considered definite if the patient has Charcot's Triad or if the patient has all of the following: evidence of inflammatory response (elevated WBC's or CRP), abnormal LFT's, or biliary dilatation

-Management includes monitoring and treating for sepsis, empiric antibiotic coverage (Unasyn or Zosyn), and establishing biliary drainage with ERCP

-Primary sclerosing cholangitis (PSC)is a chronic progressive disorder that has fibrosis, strictures of the medium an large ducts in the intrahepatic or extrahepatic biliary tree
-PSC eventually leads to complications of cholestasis and hepatic failure
-Needs a liver transplant eventually
-Most patients with PSC have ulcerative colitis
-Patients with PSC  may be asymptomatic until diagnosed on abnormal lab results or may be symptomatic
-PSC symptoms include jaundice, hepatomegaly, splenomegaly, pruritus, fatigue and excoriations
-Labs may reveal an elevated alkaline phosphatase, elevated bilirubin,  mildly elevated aminotransferases
-some patients with have high gamma globulin levels, increased IgM levels, atypical perinuclear antineutrophil cytoplasmic antibodies (P-ANCA), and Human Leukocyte Antigen DRw52a
-Ultrasound may have evidence of abnormal ducts but is usually not diagnostic
-Diagnosis is usually supported by characteristic appearance on cholangiography (MRCP, ERCP)
-Liver biopsy may support PSC


-Cholelithiasis-

 -the majority of patients with gallstones are asymptomatic
-about 20 percent of patients will develop symptomatic gallstones over 15 years

-major sequelae of gallstones include cholecystitis, choledocholithiasis, acute cholangitis, and gallstone pancreatitis
-acute cholecystitis is the most common complication
-choledocholithiasis is a stone in the common bile duct
-Sphincter of Oddi Dysfunction is a clinical syndrome of biliary or pancreatic obstruction related to mechanical or functional abnormalities of the sphincter or Oddi

-the four F's of gallbladder disease female (estrogen), fat (obesity), fertile (pregnancy), forty are conditions that cause biliary stasis

-patients with uncomplicated cholelithiasis present with RUQ or epigastric abdominal pain after eating.  The pain may radiate to the back.  There may be accompanied nausea and vomiting
-atypical symptoms may include chest pain or non specific abdominal pain
-if there is fever, jaundice, abnormal LFT's or abnormal pancreatic enzymes suggest a complication of gallstones
-Biliary colic is an intense, dull discomfort in the RUQ or epigastrium that radiates to the back or right shoulder.  The pain typically lasts for 30 minutes and plateaus after about an hour.  The pain usually resolves after 6 hours
-eating a fatty meal is a common trigger for gallbladder contraction

-physical exam reveals mild RUQ or epigastric tenderness.  These patients are usually not ill or febrile

-the study of choice for diagnosis is ultrasound.  CT scan of the abdomen is less sensitive
-HIDA scan is a test of biliary function or problem with cystic duct.  If reduced ejection fraction=biliary dyskinesia

-pain control can be achieved with NSAIDS or opioids
-cholecystectomy is eventually needed

Stomach

Stomach-

-Gastroesophageal Reflux Disease (GERD)-

-the term gastroesophageal reflux disease is applied to patients with symptoms suggestive of reflux or complications
-patients with GERD do not necessarily have inflammation
-GERD is a condition that develops when the reflux of stomach contents that causes symptoms
-most common symptoms are pyrosis, regurgitation, and dysphagia
-GERD can cause bronchospasm laryngitis and chronic cough
-most patients experience the pyrosis post prandial
-other symptoms of dysphagia include chest pain, water brash, globus sensation, odynophagia, and nausea
-diagnosis of GERD can be made from clinical symptoms alone
-differential diagnosis includes:  infectious esophagitis, pill esophagitis, eosinophilic esophagitis, peptic ulcer disease, non ulcer dyspepsia, biliary tract disease, coronary artery disease, and esophageal motility disorders
-ambulatory pH monitoring is useful for those with persistent symptoms who do not have evidence for mucosal damage on endoscopy


-Antacids are use to relief of mild GERD symptoms that occur less than once a week.  Do not prevent  GERD
-Surface agents and alginates (Sucralfate) adheres to mucosal surface, promotes healing, and protects injury
-Histamine 2 Receptors Blockers (H2 Blockers) decrease the secretion of acid by inhibiting the histamine 2 receptor of the parietal cells
-Proton Pump Inhibitors (PPI's) should be used in patients ho fail twice a day H2 Blocker therapy and patients with erosive esophagitis or two or more episodes per week of symptoms
-PPI's irreversibly bind to and inhibit hydrogen potassium ATPase pump



-Gastritis-

-Gastric inflammatory disease is classified into gastritides and gastropathies
-Gastritis is a inflammatory process, unlike gastropathy that has minimal or no inflammation
-a mucosal biopsy distinguishes between acute gastritis, chronic gastritis, and gastropathy.

-H. Pylori can be tested non invasively for gastritis
-low serum pepsinogen I levels strongly are associated with extensive intestinal metaplasia
-accuracy of biopsy is dependent of optimizing the site and number of specimens

-Causes of gastropathy include NSAIDS, alcohol, bile, circulatory failure, and chronic congestion
-Causes of gastritis include infectious agents such as H. Pylori, autoimmune and hypersensitivity reactions

-Granulomatous gastritis is a subtype of chronic gastritis that can be infectious, noninfectious, or idiopathic
-Noninfectious causes include Crohns Disease, Sarcoidosis, Adenocarcinoma, and MALT lymphoma
-Infectious causes include H. Pylori
-Up to 25 percent of the causes of granulomatous gastritis are idiopathic
-Treatment is directed at determining the etiology

-Metastatic Atrophic Gastritis is chronic gastritis, in addition to inflammation, has mucosal thinning, gland loss, and changes in epithelial cell types

-Gastritis is treated at finding cause and using antacids, surface agents, histamine blockers, and proton pump inhibitors



-Gastric Neoplasms-

-Over 90 percent of the gastric cancers are adenocarcinoma
-About 5 percent of the gastric cancers are lymphomas
-MALT (Mucosa Associated Lymph Tissue) lymphomas are associated with H.Pylori infections

-H.Pylori infections can progress to chronic active gastritis that can progress intestinal metaplasia that can progress to dysplasia which progresses to adenocarcinoma

-Signs and symptoms of gastric neoplasm include:  abdominal discomfort, early satiety, nausea, vomiting, gastrointestinal bleeding, iron deficiency anemia, or frank GI bleeding.  Anorexia or weight loss may accompany other symptoms
-Signs of metastatic disease can be found sometimes on physical exam Virchow (left subclavicular) node, a Blummer shelf (mass in the perirectal pouch, found on digital rectal exam), and a Krukenberg tumor (metastasis to the ovaries)

-Many paraneoplastic syndromes have been associated with gastric adenocarcinoma:  Trousseau's syndrome (thrombosis),  acanthosis nigricans (pigmented dermal lesions), membranous neuropathy, microangiopathic hemolytic anemia, Leser Trelat sign (seborrheic keratosis), and dermatomyositis

-Diagnosis usually made with endoscopy with biopsy
-Gastric carcinomas may appear ulcers, masses, or enlarged gastric folds
-CT scan may detect metastasis in the lung and liver but is otherwise poor for staging
-Laparoscopy is sometimes used for staging

-Surgical resection of the gastric cancer and removal of all gross and microscopic disease
-Chemotherapy and radiation therapy have proven not to be beneficial in treatment or palliation



-Peptic Ulcer Disease-

-Peptic Ulcer Disease (gastric and duodenal ulcers) is a loss of the lining of the stomach or duodenum
-the risk factors for peptic ulcer disease are H. Pylori infection, NSAIDS, and unopposed hypergastrinemia with Zollinger Ellison syndrome.
-Ulcers aère an end result of imbalance of aggressive and defense factors in the gastroduodenal mucosa
-H. Pylori, NSAIDS, and acid secretory abnormalities are major factors that disrupt the equilibrium
-Duodenal and gastric ulcers develop in the minority of patients with H. Pylori
-Duodenal ulcers involves enhanced gastric secretion caused by dysregulation of somatostatin and gastrin.  Gastrin release is increase.  HCO3 secretion is inhibited by H. Pylori infection

-Dyspepsia is the cardinal symptom of peptic ulcer disease
-Other symptoms of PUD includes upper abdominal pain, fullness, bloating, distention and nausea

-Four diagnostic approaches for dyspepsia include:  a trial of antacids, immediate endoscopy, non invasive testing for H. Pylori followed by antibiotic treatment for positive patients, and empirical antibiotic therapy for H. Pylori with no testing

-Invasive tests for H. Pylori include rapid urease test, histology and culture.  The CLO test on biopsy
-Non invasive tests for H. Pylori include:  serology and urea breath test

-Treatment options for PUD include H2 Blockers, Proton Pump Inhibitors, Antacids, and Sucralfate

-Treatment of H. Pylori involves 2 antibiotics plus proton pump inhibitors or ranitidine plus bismuth
-Antibiotic combinations can include clarithromycin and metronidazole, metronidazole plus tetracycline, or amoxicillin plus clarithromycin

-consider stopping NSAIDS

-surgery really does not have a role in management of PUD

-PUD is the most common cause of upper GI bleeding and occurs in 15-20 percent of the patients with PUD
-Bleeding resolves itself about 80 percent of the time, can lead to death 6-7 percent of the time

-Gastric outlet obstruction can occur by a pyloric channel or duodenal ulceration in the setting of acute ulceration.  Edema, spasm or inflammation causes the obstruction

-Perforation occurs when there is ulcer penetration through the full thickness of the stomach and duodenum

-Zollinger Ellison Syndrome is characterized by hypersecretion of acid caused by elevated levels of gastrin from a gastrin secreting tumor.
-ZE syndrome should be suspected with recurrent PUD in the absence of H. Pylori infection or NSAID consumption
-the diagnosis of ZE syndrome is made with high levels of gastrin fasting in the setting of gastrin acid hypersecretion
-Surgical resection of the gastrin secreting tumor in the standard in ZE syndrome


-Pyloric Stenosis-

-pyloric stenosis is characterized by hypertrophy of the pylorus with elongation and thickening progressing to a near complete gastric outlet obstruction
-more common in males and females
-Thirty percent of the cases are in the first born children
-Maternal smoking during pregnancy increases the risk

-classic presenting symptoms are 3-6 week old baby who has immediate postprandial, non villous projectile vomiting and demands to be refer after the vomiting episode

-patients are described as being emaciated and dehydrated with a palpable "olive like" mass at the lateral edge of the rectus abdominus muscle in the RUQ

-labs usually reveal a low chloride and a metabolic acidosis
-diagnosis can be confirmed with a ultrasound or upper GI

-Surgical treatment is a pyloromyotomy
-surgery should be delayed until metabolic derangement and dehydration is corrected if present

Esophagus

Esophagus-


-Esophagitis-

-Many causes of esophagitis

-Eosinophillic Esophagitis is found in up to 15 percent of patients with dysphagia.
-Typically have stacked circular rings, strictures, linear furrows and white papules that can lead to food impaction
-Diagnosis is made by biopsy
-Treated by elimination of dietary elements that cause allergic response.  Start patient on proton pump inhibitor.
-Topical steroids can be helpful in eosinophillic esophagitis
-Esophageal dilation necessary for patients with symptomatic strictures

-Radiation esophagitis may occur in patients being treated for head, neck, or thoracic cancers.
-these patients have dysphagia and odynophagia

-Lymphocytic esophagitis is when there is a dense peripapillary lymphocytic infiltrate involves the lower two thirds of the esophageal epithelium
-etiology is unknown
-Usually seen in older patients
-treat with proton pump inhibitor.  May not be associated with GERD

-Infectious Esophagitis due to many causes.  Most common herpes simplex virus
-Other causes of infectious causes such as cytomegalovirus (CMV), candidia, cryptococcosis, histoplasmosis, blastomycosis, and aspergilliosis
-immunosuppression should be suspected if present

-Medication Induced Esophagitis caused by largely 3 groups of medications:  antibiotics, NSAIDS and others
-Doxcycline is the most common antibiotic causing medication induced esophagitis
-NSAIDS can cause but higher with ASA
-Major players in the others category: KCl, quinidine, and biphosphonates
-mechanism is by caustic injury to the esophagus
-sometimes can be caused by retention of the capsule or scratching of the esophagus
-the most important therapy is to take the offending medication away
-PPI's, antacids, and carafate can be prescribed but their value has not been significantly demonstrated.

-Reflux esophagitis is due to hydrogen ion diffusion into the mucosa leading to cellular acidification and necrosis
-impaired esophageal emptying or decreased salivary function can contributed to increased exposure of the esophagus to the acid and induce this pathology
-Treatment is directed as acid control or increasing esophageal emptying

-if bleeding is present, melena is much more common the hematemesis
-other signs of esophagitis include pyrosis, dysphagia, bleeding, and possible pulmonary aspiration
-history is important in the diagnosis.  Non exertional and lasting for hours usually points to a non cardiac etiology
-other key elements include possibly awakens from sleep, worse after meals, and aggravated by laying down.
-usually improved with standing or sitting up.
-Treatment can involve PPI, H2 blockers, antacids, reglan (helps gastric emptying), and carafate
-non pharmacologic measures include weight loss, elevating head of the bed, and eliminating eating before bedtime or laying down.


-Motility Disorders-

-Motility disorders of the esophagus can occur from the upper esophageal sphincter (UES) or lower esophageal sphincter (LES) and body of the esophagus

-oropharyngeal motility disorders may arise from dysfunction of UES such as Zenker's diverticulum or cricopharyngeal bar.
-Can also be caused by stroke, multiple sclerosis, amytrophic lateral sclerosis, brain tumors, muscular dystrophy, myasthenia gravis, cancer, goiter, or cervical spurs.
-high incidence of aspiration with these disorders
-diagnosis with rapid sequence cine-esophagography.  Endoscopy plays a supportive role
-treatment is directed at reversing potential causes, aspiration precautions, and considering PEG tube if the underlying disorder is at high risk of aspiration

-the body of the esophagus can have motility disorders that arise from the smooth muscle or the intrinsic nervous system
-Scleroderma affects the smooth muscle of the esophagus and achalasia and Chagas disease are affected of by disorders of the intrinsic nervous system
-Other disorders can cause diffuse esophageal spasm
-cine esophagography and esophageal manometry confirms the diagnosis
-Achlasia usually responds to brisk dilation of the LES or surgical myotomy
-Scleroderma patients should have aggressive treatment of GERD
-patients with diffuse esophageal spasm sometimes will get some relief with calcium channel blockers, nitroglycerin or anticholinergic patients

-Rings and webs can affect the proximal or distal (Schatzki's rings)
-can cause some intermittent dysphagia especially when eat solid foods


-Mallory Weiss Tear-

-Mallory Weiss tear is defined as longitudinal mucosal lacerations (intramural dissections) in the distal esophagus and proximal stomach which are caused by retching.
-hiatal hernia is found in a high percentage of patients with Mallory Weiss tears
-alcoholism is a predisposing factor.  Bleeding can be more severe with portal hypertension or esophageal varices
-presenting symptoms are acute GI bleeding, epigastric abdominal pain or back pain
-bleeding occurs because of a tear that involves the esophageal venous or arterial plexus
-patients usually have non bloody vomitus before the bleeding starts
-high percentage of patient need a blood transfusion but bleeding is self limited
-endoscopic therapy is first line treatment in actively bleeding lacerations
-injections with epinephrine, ethanol, or other sclerosing agents are helpful
-can use thermal devices also


-Esophageal Neoplasms-

-most esophageal cancers are squamous cell or adrenocarcinomas
-Barrett's esophagus can give rise to adenocarcinoma
-small cell carcinoma and sarcoma can arise out of the distal esophagus
-family aggregation has been described with a high incidence of squamous cell carcinoma in China.
-family history is a good indicator for Barrett's esophagus
-the presence of underlying esophageal disease such as achalasia and caustic strictures increases the risk of esophageal cancer
-prior gastrectomy increases the risk for squamous cell carcinoma
-atrophic gastritis, human papilloma virus, tylosis, biphosphonates, and poor oral hygiene have been shown to increase the risk of esophageal cancer
-Most all of adenocarcinomas arise from a region of Barrett's esophagus which is due to GERD
-Smoking increases the risk form adenocarcinoma of the esophagus
-alcohol consumption does not increase the risk for esophageal adenocarcinoma
-Obesity has been liked to esophageal adenocarcinoma and adenocarcinoma of the gastric cardia
-Zollinger Ellison Syndrome may be at increased risk for adenocarcinoma
-use of drugs that decreased lower esophageal sphincter pressure may increases the risk of adenocarcinoma
-cholecystectomy and nitrosative stress have been associated with carcinogenesis
-NSAIDS may have a protective effects


-patients with locally advanced cancer can cause some solid food dysphagia
-weight loss may happen from dysphagia
-aspiration pneumonia can happen but infrequent
-chronic GI blood loss is common with esophageal cancer with melena
-tracheobronchial fistulas are a late complication of esophageal cancer because of the direct invasion through the esophageal wall to the main stem bronchus

-esphagectomy is the treatment of choice for superficial esophageal cancers
-the cancer has to be staged as well as the depth determined
-evaluation for distant metastasis can be done with CT or PET scanning
-criteria for unresectable disease includes: distant metastasis to peritoneal, lung, bone, adrenal, brain, or liver mets, thoracic or abdominal esophagus near great vessels, heart or trachea, cervical esophageal tumors
-palliative surgical resection is usually not indicated
-external beam radiation therapy (EBRT) is indicated for unresectable cancer
-chemotherapy and radiation therapy is the standard nonoperative management for unresectable therapy



-Esophageal Stricture-

-most benign esophageal strictures result from a complication of long standing GERD
-treated with acid reducers as well as esophageal dilation therapy
-other causes of strictures can be secondary to external beam radiation, esophageal sclerotherapy, caustic ingestions, surgical anastamosis, and rare dermatologic diseases
-the cardinal symptom of of strictures is dysphagia
-contraindications to esophageal dilation include:  incomplete healed perforation, potentially malignant stricture, pharyngeal or cervical deformity, caution with eosinophilic esophagitis, large thoracic aneurysm, and impacted food bolus
-can be dilated with balloon dilators or mechanical dilators
-simple strictures are related to reflux esophagitis
-complex strictures are long, narrow, tortuous, or strictures associated with hiatal hernias and esophageal diverticulae.



-Esophageal Varices-

-varices are expanded blood vessels in the esophagus and sometimes the stomach
-cirrhosis blocks the blood flow through the liver and this increases the pressure in the portal vein causing portal hypertension
-without treatment 25-40 percent of patients with esophageal varices will have one major episode of bleeding
-15 percent of the people who bleed from varices will die
-varices do not cause symptoms until the bleed or ruptures

-Treatment involves beta blockers for those that have refractory ascites
-patients need to avoid alcohol and lose weight
-variceal band ligation can be placed around the varices to prevent them from bleeding
-PPI's help speed the healing of erosions and ulcers that develop when the band falls off the varices.
-if they rupture will need massive blood transfusion, volume replacement, and emergent endoscopy