Lecture 2 Infections Gi Tract (2)

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Lecture 2 Infections Gi Tract (2)

  1. 1. Gastroenteritis, Infections of the GI Tract, and Diarrhea
  2. 2. Gastroenteritis <ul><li>Gastroenteritis is a nonspecific term for various pathologic states of the gastrointestinal tract. </li></ul><ul><li>The primary manifestation is diarrhea, but it may be accompanied by nausea, vomiting, and abdominal pain. </li></ul><ul><li>A universal definition of diarrhea does not exist, although patients seem to have no difficulty defining their own situation. </li></ul><ul><ul><li>Although most definitions center on the frequency, consistency, and water content of stools </li></ul></ul>
  3. 3. Gastroenteritis <ul><li>Defined as- Inflammation of the mucous membrane of both the stomach and intestine, usually causing nausea, vomiting, and diarrhea. </li></ul><ul><li>Acute gastroenteritis usually causes profuse watery diarrhea, often c nausea and vomiting, but without localized findings. </li></ul><ul><li>Between cramps, the abdomen is completely relaxed. </li></ul>
  4. 4. Cause of Gastroenteritis <ul><li>Infectious agents usually cause acute gastroenteritis. </li></ul><ul><li>These agents cause diarrhea by adherence, mucosal invasion, enterotoxin production, and/or cytotoxin production. </li></ul><ul><li>These mechanisms result in increased fluid secretion and/or decreased absorption. </li></ul><ul><li>This produces an increased luminal fluid content that cannot be adequately reabsorbed, leading to dehydration and the loss of electrolytes and nutrients. </li></ul>
  5. 5. Infantile Gastroenteritis- <ul><li>An endemic viral infection of young children </li></ul><ul><ul><li>(6 mo-12 yrs) </li></ul></ul><ul><li>is especially widespread during winter, </li></ul><ul><li>caused by strains of rotavirus ; </li></ul><ul><li>the incubation period is 2-4 days, </li></ul><ul><li>with symptoms lasting 3-5 days, </li></ul><ul><li>including abd. pain, diarrhea, fever, and vomiting. </li></ul><ul><li>Tx = Fluids (PO vs. IV) </li></ul>
  6. 6. Epidemic Gastroenteritis- <ul><li>An epidemic, highly communicable but rather mild disease of sudden onset, </li></ul><ul><li>caused by the epidemic gastroenteritis virus (especially Norwalk agent), </li></ul><ul><li>with an incubation period of 16-48 hrs </li></ul><ul><li>and a duration of 1-2 days, </li></ul><ul><li>affects all age groups; </li></ul><ul><li>infection is associated with some fever, abd. cramps, nausea, vomiting, diarrhea, and headache, </li></ul>
  7. 7. Causes of Vomiting and Diarrhea <ul><li>GASTROENTERITIS MNEUMONIC </li></ul><ul><li>G astrointestinal- Obstruction, Dymotility, Inflammation, Malabsorption, Lactose Intolerance, GI bleeding </li></ul><ul><li>A ppendicitis or aorta </li></ul><ul><li>S pecific diseases- Glaucoma, Torsion (ovary/testicle) </li></ul><ul><li>T rauma </li></ul><ul><li>R x (prescription)-medication side effects </li></ul><ul><li>O bstetrics and Gynecology-pregnancy, preeclampsia, Hyperemesis gravidarum </li></ul><ul><li>E ndocrine or metabolic-thyrotoxicosis, DKA, Adrenal insufficiency </li></ul><ul><li>N eurologic-Vestibular, Migraine, encephalopathy, Hydrocephalus, Increased ICP (neoplasms, subdural, epidural, or subarrachnoid hemorrhage, cerebral edema) </li></ul><ul><li>T oxicology </li></ul><ul><li>E nvironmental-Food poisoning, envenomation, high altitude, acute radiation </li></ul><ul><li>R enal-Obstructive uropathy, renal colic </li></ul><ul><li>I nfection- gastroenteritis (viral, bacterial, parasitic), pyelonephritis, pneumonia (pertussis, Legionella), PID, Meningitis, Hepatitis, colitis, HIV </li></ul><ul><li>T umors-gastrinoma, thyroid ca, villous adenoma </li></ul><ul><li>I schemia- MI, Mesenteric ischemia, ischemia colitis </li></ul><ul><li>S upratentorial- Bulemia, psychosocial stress </li></ul>
  8. 8. Gastroenteritis <ul><li>Causes: </li></ul><ul><ul><li>Viral 50-70% </li></ul></ul><ul><ul><ul><li>Norwalk virus </li></ul></ul></ul><ul><ul><ul><li>Caliciviruses </li></ul></ul></ul><ul><ul><ul><li>Rotavirus </li></ul></ul></ul><ul><ul><ul><li>Adenovirus </li></ul></ul></ul><ul><ul><ul><li>Parvovirus </li></ul></ul></ul><ul><ul><ul><li>Astrovirus </li></ul></ul></ul><ul><ul><li>Bacterial 15-20% </li></ul></ul><ul><ul><ul><li>Salmonella, Shigella, and Campylobacter species are the top 3 leading causes of bacterial diarrhea worldwide, followed closely by Aeromonas species </li></ul></ul></ul><ul><ul><li>Parasitic 10-15% </li></ul></ul><ul><ul><li>Others </li></ul></ul>
  9. 9. Gastroenteritis <ul><li>Acute symptoms may follow a wide variety of infectious & chemical agents </li></ul><ul><li>Ingestion may occur as a result of person to person contact, more commonly via water or food </li></ul><ul><li>The majority of food borne illnesses are caused by staphylococcus aureus from contaminated food being allowed to stand, producing endotoxins. </li></ul><ul><li>Salmonella & Clostridium follow staph poisoning as most common. They are found in meats. </li></ul>
  10. 10. Gastroenteritis <ul><li>Invasive Infection : The organism enters the mucosal cells, destroys them, causing diarrhea usually with blood in the stool. </li></ul><ul><li>Enterotoxic syndromes: The organisms do not invade the mucosa, but produce enterotoxins of which act as chemical mediators causing hypersecretion of the fluid. Little damage to the tissue is done. </li></ul>
  11. 11. Gastroenteritis Key Symptoms <ul><li>Viral </li></ul><ul><ul><li>Abdominal cramps (#1) </li></ul></ul><ul><ul><li>Vomiting </li></ul></ul><ul><ul><li>Profuse watery stools </li></ul></ul><ul><ul><li>Myalgias </li></ul></ul><ul><ul><li>Fever </li></ul></ul><ul><ul><li>Headaches </li></ul></ul><ul><ul><li>Arthralgias </li></ul></ul><ul><li>Bacterial Dysentery </li></ul><ul><ul><li>Small volume stools </li></ul></ul><ul><ul><li>Fever </li></ul></ul><ul><ul><li>Tenesmus </li></ul></ul><ul><ul><li>Bloody mucoid stools </li></ul></ul><ul><ul><li>Suprapubic pain relieved by BM </li></ul></ul>
  12. 12. Gastroenteritis (cont.) <ul><li>Historical Information </li></ul><ul><ul><li>History of suspicious food eaten within the last 48 hrs, eating an unusual food (special fish) in a restaurant, or preparing food in an unconventional container (copper). Or a hx of similar illness in others who ate with the patient. </li></ul></ul>
  13. 13. Gastroenteritis (cont.) <ul><li>Physical Exam Findings </li></ul><ul><ul><li>Minimally helpful </li></ul></ul><ul><ul><li>Abdominal tenderness </li></ul></ul><ul><ul><li>Diarrhea causing dehydration </li></ul></ul><ul><ul><li>Fever- usually indicates organism invasion </li></ul></ul><ul><ul><li>Hypotension- usually indicates dehydration and electrolyte imbalance </li></ul></ul><ul><ul><li>Rectal Exam- “to bleed or not to bleed” </li></ul></ul>
  14. 14. Gastroenteritis (cont.) <ul><li>Laboratory: </li></ul><ul><ul><li>Stool Culture </li></ul></ul><ul><ul><li>Hemoccult of stool </li></ul></ul><ul><ul><li>Fecal leukocytes </li></ul></ul><ul><ul><li>CBC; If WBC count is elevated increased likelyhood of bacterial infection. </li></ul></ul><ul><ul><ul><li>(If eosinophils present r/o parasitic infection). </li></ul></ul></ul><ul><ul><li>If C. Difficile is suspected request cytotoxin of stool </li></ul></ul><ul><li>Treatment: </li></ul><ul><ul><li>With the exception of Giardiasis, amebiasis, C. difficile, salmonellosis, & shigellosis, practically all only need fluid replacement, glucose, and electrolyte control (IV NS, pedialyte) </li></ul></ul>
  15. 15. Gastroenteritis (cont.) <ul><li>Incubation period </li></ul><ul><ul><li>Chemical poisons : onset immediate after ingestion of food like Ciguatera or scromboid (scrombotoxin found in fish) </li></ul></ul><ul><ul><li>Staphylococcal food poisoning : onset within hrs after eating contaminated food </li></ul></ul><ul><ul><li>Salmonella & Shigella infection : onset usually within 24-48 hrs (bacillary dysentery) </li></ul></ul><ul><ul><li>Giardiasis infection : onset of symptoms after one week with recurrent diarrhea. </li></ul></ul>
  16. 16. Gastroenteritis (cont.) <ul><li>Incubation period (cont.) </li></ul><ul><ul><li>Clostridium difficile: Antimicrobial use within the last 2 weeks </li></ul></ul><ul><ul><li>Botulism : Associated Neurological symptoms after eating canned food. Symptoms within 24 hrs. </li></ul></ul><ul><ul><li>A h/o homosexuality : r/o AIDS, Shigella, Campylobacter jejuni, Salmonella, protozoalike Entamoeba, cryptosproidia, candida, giardiasis, and many others </li></ul></ul>
  17. 17. Gastrointestinal Infectious Disorders <ul><li>Viral </li></ul><ul><li>Staphlococcal </li></ul><ul><li>Cholera </li></ul><ul><li>Shigellosis </li></ul><ul><li>Salmonella </li></ul><ul><li>Hemorrhagic Colitis (E. coli O157:H7) </li></ul><ul><li>Pseudomembranous Colitis (C. difficile) </li></ul><ul><li>Enterotoxigenic E. coli </li></ul>
  18. 18. Viral Gastroenteritis <ul><li>N/V/D/ abd cramps </li></ul><ul><li>Norwalk - </li></ul><ul><ul><li>common year-round </li></ul></ul><ul><ul><li>This is the leading cause of viral gastroenteritis in the United States </li></ul></ul><ul><li>Caliciviruses </li></ul><ul><ul><li>Various caliciviruses, other than Norwalk virus, are likely responsible for many outbreaks of previously unidentified viral gastroenteritis. </li></ul></ul><ul><li>Rotavirus </li></ul><ul><ul><li>This is the leading cause of gastroenteritis in children (> in winter), but can also be found in adults. Rotavirus may cause severe dehydration. </li></ul></ul><ul><li>Others </li></ul><ul><ul><li>Enterovirus, Coxsackie virus A1, echovirus, adenovirus </li></ul></ul><ul><li>Often occur in epidemic fashion in closed environments (eg, cruise ships, schools) </li></ul><ul><li>Viral cultures rarely indicated; ELISA and PCR assays </li></ul><ul><li>Fecal Leukocytes absent </li></ul><ul><li>Self limiting; although, hospitalization and rehydration may be needed in severe cases </li></ul>
  19. 19. Staphylococcal Gastroenteritis <ul><li>From foods left @ room temperature, particularly milk, cream products, and some meat and fish. </li></ul><ul><li>Within 8 hrs p eating, N/V/D/F/HA, cramps </li></ul><ul><li>Completely recovering p 24 hrs </li></ul><ul><li>h/o similar illness in others eating same food. </li></ul><ul><li>Fecal leukocytes are usually absent. </li></ul><ul><li>Laboratory studies to distinguish b/t this and viral do not change management and are usually not done. </li></ul><ul><li>Tx: fluids and electrolyte maintenance </li></ul>
  20. 20. Cholera <ul><li>Vibrio Cholerae </li></ul><ul><li>Secretory Diarrhea </li></ul><ul><li>Spread by fecal contamination of water, seafood, and other products. </li></ul><ul><li>Endemic in Gulf Coast of US, Asia, Africa, Middle East. </li></ul><ul><li>Epidemics, contaminated water supplies effects all in all seasons </li></ul><ul><li>“ Rice-Water” stools, painless, non-bloody diarrhea </li></ul><ul><li>Severe Dehydration=thirst, oliguria, anuria, cramps, weakness, decrease turgor </li></ul><ul><li>Circulatory collapse= cyanosis, stupor, renal tubular necrosis, death </li></ul><ul><li>Metabolic Acidosis may be severe b/c of lost bicarbinate </li></ul><ul><li>Dx: stool cx, </li></ul><ul><ul><li>Fecal Leukocytes (WBC’s) absent </li></ul></ul><ul><li>Tx: Maintain fluid and electrolyte balance. </li></ul><ul><ul><li>Tetracycline or doxycycline reduces duration of symptoms </li></ul></ul>
  21. 21. Shigellosis <ul><li>Shigella </li></ul><ul><li>Dysentery (bloody diarrhea) </li></ul><ul><li>Only need to ingest small inoculum </li></ul><ul><li>Fecal-Oral spread, and contaminated foods, also flies act as mechanical vectors </li></ul><ul><li>Epidemics occur c overcrowding and insufficient sanitation, and reinfection possible. </li></ul><ul><li>Young children- acute onset of sx: f/n/v/d/abd pain/distention </li></ul><ul><li>Within 3 days diarrhea becomes severe and bloody, often with pus, and mucus. </li></ul><ul><li>Dehydration can cause death; otherwise acute ds. resolves within several days. (Adults have milders sx) </li></ul><ul><li>Dx: stool cx, proctoscopy, </li></ul><ul><ul><li>Fecal Leukocytes (WBC’s) PRESENT </li></ul></ul><ul><li>Tx: </li></ul><ul><ul><li>Fluid replacement is critical </li></ul></ul><ul><ul><li>Bactrim or Cipro can shorten course of severe ds </li></ul></ul><ul><ul><li>DO NOT GIVE ANTI-DIARRHEALS, may prolong course </li></ul></ul>
  22. 22. Salmonella <ul><li>3 types </li></ul><ul><ul><li>1. Gastroenteritis is most common form of Salmonellosis </li></ul></ul><ul><ul><li>2. Enteric Fever- Typhoid Fever </li></ul></ul><ul><ul><li>3. Bacteremia </li></ul></ul><ul><li>Eating foods produced from infected animals; meat, milk, poultry, eggs, and drinking contaminated water; and from fecal-oral trans. </li></ul><ul><li>Incubation period 8-48 hrs </li></ul><ul><li>Asymptomatic or symptoms develop within 2 days of eating infected food. </li></ul><ul><ul><li>N/cramps/watery or bloody diarrhea/fever/ and sometimes vomiting </li></ul></ul><ul><ul><li>lasting 1-4 days </li></ul></ul><ul><li>Dx: stool cx, Presence of fecal WBC’s variable </li></ul><ul><li>Tx: </li></ul><ul><ul><li>supportive (IV hydration) </li></ul></ul><ul><ul><li>Antibiotics usually not necessary for Salmonella gastroenteritis (Bactrim, Amp, or Cipro indicated in pt’s c increased risk of mortality, Typhoid fever, or Bacteremia) </li></ul></ul>
  23. 23. Hemorrhagic Colitis <ul><li>Escherichia coli O157:H7 </li></ul><ul><li>Produces a toxin that damages GI mucosa and vascular endothelial cells (vessels), other organs, particularly the kidneys. </li></ul><ul><li>Organism has bovine reservoir: unpasteurized milk and undercooked beef; Fecal-oral transmission also possible </li></ul><ul><li>S/S: Acute, severe abd cramps and watery diarrhea progresses to bloody diarrhea; low grade fever, uncomplicated lasts ~1wk; but complicated cases=high fever, hemolytic uremic syndrome (HUS) or thrombocytopenic purpura (TTP) </li></ul><ul><li>Dx: Stool cx; fecal leuks usually absent </li></ul><ul><li>Tx: Supportive (IV hydration), Abx do not help ; complications require aggressive management </li></ul>
  24. 24. Pseudomembranous Colitis <ul><li>Clostridium difficile </li></ul><ul><li>Caused by antibiotic therapy which changes balance of normal intestinal flora, causing overgrowth of pathogen (most common causes clindamycin, ampicillin, and cephalosporins, although any can be cause) </li></ul><ul><li>Hospitalized pt’s on Abx at greatest risk </li></ul><ul><ul><li>Usually within 2 wks after starting Abx, but may be as long as 6 wks after. </li></ul></ul><ul><li>Illness often mild, but severe bloody diarrhea with abd cramps, fever, and dehydration may occur. </li></ul><ul><li>Dx: C. difficile toxin in stool is diagnostic; stool cx or sigmoidoscopy with visualization of pseudomembranes </li></ul><ul><li>Tx: D/C Abx if possible , may be sufficient </li></ul><ul><ul><li>Metronidazole or PO vancomycin in more severe cases </li></ul></ul>
  25. 25. Traveler’s Diarrhea <ul><li>Most commonly caused by bacteria (80%), Enterotoxigenic E. coli, Shigella, Campylobacter jejuni being the most common pathogens. </li></ul><ul><li>Chronic watery diarrhea </li></ul><ul><li>Up to 10 or more loose stools per day, usually without blood or mucus. </li></ul><ul><li>Fever is rare </li></ul><ul><li>Self limiting within 1-5 days </li></ul><ul><li>Dx: stool cx for pt’s c f/dysentery, and those that don’t respond to abx </li></ul><ul><li>Tx: mostly symptomatic therapy (IV hydration) </li></ul><ul><ul><li>If high fever, or dysentery tx c Cipro (not antidiarrheals) </li></ul></ul><ul><li>Prevention: Prophylaxis is recommended for those with significant underlying ds. </li></ul><ul><ul><li>Cipro </li></ul></ul><ul><ul><li>Pepto-bismol is effective, but may interfere with the absorption of other medications (tetracycline/doxycycline) used for malaria prophylaxis, and it also carries the same toxicity as other salicylates (Reyes Syndrome) and turns the tongue and stool black, so it is rarely used. </li></ul></ul>
  26. 26. General Bacterial Overgrowth Treatment <ul><li>Usually self limiting </li></ul><ul><li>IV hydration </li></ul><ul><li>Correct the anatomic defect when possible. </li></ul><ul><li>Empiric antibiotic trial can be used as a diagnostic and therapeutic maneuver. </li></ul><ul><li>Ciprofloxacin (or combo c Metronidazole) </li></ul><ul><ul><li>(However often not necessary, unless dysenteric) </li></ul></ul>
  27. 27. Protozoal Infection
  28. 28. Protozoal infection signs/symptoms <ul><li>Abdominal pain </li></ul><ul><li>Wheezing or hemoptysis due to pulmonary migration of larva (lofflers syndrome) </li></ul><ul><li>Dermatitis </li></ul><ul><li>Diarrhea </li></ul><ul><li>Dysentery </li></ul><ul><li>Pruritis </li></ul><ul><li>Rectal Prolapse </li></ul><ul><li>Steatorrhea </li></ul><ul><li>Passage of parasites </li></ul><ul><li>Bowel obstruction (as found in taenia and ascarisis) </li></ul>
  29. 29. Protozoal Infections <ul><li>History </li></ul><ul><ul><li>Travel to underdeveloped areas </li></ul></ul><ul><ul><li>Outbreak of associated illness (Giardia, Trichinella) </li></ul></ul><ul><ul><li>Daycare exposure (Giardia) </li></ul></ul><ul><ul><li>Homosexual behavior (Giardia, Entamoebia) </li></ul></ul><ul><ul><li>Animal Exposure </li></ul></ul><ul><ul><li>Diet: uncooked foods </li></ul></ul><ul><ul><li>Immunocompromised </li></ul></ul><ul><li>Physical Findings </li></ul><ul><ul><li>Weight loss </li></ul></ul><ul><ul><li>Excessive gas or abdominal distention </li></ul></ul><ul><ul><li>Hyperperistalsis </li></ul></ul><ul><ul><li>Perianal infection </li></ul></ul><ul><ul><li>Wheezing </li></ul></ul>
  30. 30. Protozoal Infections <ul><li>Tests </li></ul><ul><ul><li>Fecal smears (look for WBC’s, RBC’s, ova & parasites) </li></ul></ul><ul><ul><li>Stool Cultures </li></ul></ul><ul><ul><li>CBC: eosinophilia , iron deficiency </li></ul></ul><ul><ul><li>Graham’s Test: scotch tape test </li></ul></ul><ul><li>Treatment </li></ul><ul><ul><li>Donnagel </li></ul></ul><ul><ul><li>Kaopectate </li></ul></ul><ul><ul><li>Immodium </li></ul></ul><ul><ul><li>Bismuth Subsalicylate </li></ul></ul><ul><ul><li>Chemotherapeutic agents for each parasite </li></ul></ul>
  31. 31. Pinworms <ul><li>Etiology: Enterobius Vermicularis </li></ul><ul><li>Outbreaks common in schools </li></ul><ul><li>Transmission by fecal-oral ingestion </li></ul><ul><li>Key symptom is rectal pruritis </li></ul><ul><li>Nocturnal </li></ul><ul><li>Test is scotch tape test </li></ul><ul><li>Treatment: Vermox , Antiminth (one dose, then repeat in one week) </li></ul>
  32. 32. Giardia (Giardiasis) <ul><li>Etiology: Giardia Lamblia </li></ul><ul><li>Transmitted: fecal-oral </li></ul><ul><li>Most common water borne infection </li></ul><ul><li>Symptoms: </li></ul><ul><ul><li>Diarrhea </li></ul></ul><ul><ul><li>Abd. Pain & cramps </li></ul></ul><ul><ul><li>Flatus </li></ul></ul><ul><ul><li>Fatty, greasy, foul smelling stool (steatorrhea) </li></ul></ul><ul><li>Test: Microscopic exam of stool for cysts (also the ELISA antigen test) </li></ul><ul><li>It is an upper GI parasite and stool examination can be negative </li></ul><ul><li>Treatment: Metronidazole (Flagyl) </li></ul>
  33. 33. Amebiasis <ul><li>Etiology: Entamoeba hitolytica </li></ul><ul><li>Found in 4% of the population </li></ul><ul><li>Transmitted: fecal-oral </li></ul><ul><li>Found mostly in cecum & ascending colon, invading the mucosa. Can travel to liver, lung, brain </li></ul><ul><li>Symptoms: </li></ul><ul><ul><li>Asymptomatic to diarrhea </li></ul></ul><ul><ul><li>Abd. Cramps </li></ul></ul><ul><ul><li>Flatus, fever, hepatitis </li></ul></ul><ul><ul><li>Shoulder pain due to hepatitis </li></ul></ul>
  34. 34. Amebiasis (cont.) <ul><li>Signs: range </li></ul><ul><ul><li>No symptoms – no signs </li></ul></ul><ul><ul><li>Bloody diarrhea </li></ul></ul><ul><ul><li>Perianal ulcers </li></ul></ul><ul><ul><li>RUQ tenderness </li></ul></ul><ul><ul><li>Pulmonary (pneumonia- emphysema) </li></ul></ul><ul><li>Test: </li></ul><ul><ul><li>Examine stool for cyst –trophozoites </li></ul></ul><ul><li>Treatment: </li></ul><ul><ul><li>Metronidazole (Flagyl) </li></ul></ul>
  35. 35. Ascariasis <ul><li>Most common intestinal helminth </li></ul><ul><li>Etiology: Ascaris lumbricoides (the large intestine round worm) </li></ul><ul><li>Transmitted by contaminated food </li></ul><ul><ul><li>Human feces as fertilizer </li></ul></ul><ul><li>Pulmonary phase (Loffler’s syndrome) </li></ul><ul><li>Intestinal phase (eggs in stool) </li></ul><ul><li>Penetrate the intestine & invade liver, lung, heart </li></ul><ul><li>Tx: Albendazole and Pyrantel pamoate </li></ul>
  36. 36. Tapeworms <ul><li>Cestodes (segmented worms) </li></ul><ul><li>Taenia solium </li></ul><ul><li>Adults live in GI tract, larvae can be found in almost any organ (neuro, muscle, eye) (cysticercosis ) </li></ul><ul><li>Fish, beef, pork, dog , cats, fleas, snakes, birds, and other mammals can carry the tapeworm larva, humans can be the definitive host or the intermediate host </li></ul><ul><li>From 5mm to over 25 meters in length </li></ul>
  37. 37. Whipworm (Trichuriasis) <ul><li>Humans are the only host for this whipworm and one of the most common parasitic infections in the U.S. </li></ul><ul><li>The worm lives in the cecum and appendix </li></ul><ul><li>One female produces several thousand eggs/day </li></ul><ul><li>Fecal-oral transm., uncooked veggies, & water </li></ul><ul><li>Symptoms: allergic rxns, anemia, vague GI complaints, diarrhea & abd. distention </li></ul><ul><li>Diagnosis: stool examination </li></ul><ul><li>Tx: Albendazole, Mebendazole </li></ul>
  38. 38. Diarrhea
  39. 39. Diarrhea <ul><li>Diarrhea is both a symptom and a sign. </li></ul><ul><li>Symptom : Typically considered as an increased frequency or volume of stool (i.e., 3 or more liquid or semisolid stools daily for at least 2-3 consecutive days). </li></ul><ul><li>Sign : Diarrhea is formally defined as stool weight >200 g/24h. </li></ul>
  40. 40. Diarrhea <ul><li>Causes of diarrhea </li></ul><ul><ul><li>Psychogenic </li></ul></ul><ul><ul><li>Surgical </li></ul></ul><ul><ul><li>Endocrine </li></ul></ul><ul><ul><li>Carcinoid tumors </li></ul></ul><ul><ul><li>Mechanical </li></ul></ul><ul><ul><ul><li>Neoplasm </li></ul></ul></ul><ul><ul><ul><li>Foreign body </li></ul></ul></ul><ul><ul><li>Chemical </li></ul></ul><ul><ul><li>Bacterial </li></ul></ul><ul><ul><li>Parasitic </li></ul></ul><ul><ul><li>Saline Cathartics </li></ul></ul><ul><ul><li>Dietary </li></ul></ul><ul><ul><li>Allergic </li></ul></ul><ul><ul><li>Malabsorption </li></ul></ul><ul><ul><ul><li>Tropical sprue </li></ul></ul></ul><ul><ul><ul><li>Celiac ds. </li></ul></ul></ul><ul><ul><ul><li>Whipple’s ds. </li></ul></ul></ul>
  41. 41. Diarrhea <ul><li>Acute vs. Chronic </li></ul><ul><ul><li>Acute Diarrhea </li></ul></ul><ul><ul><ul><li>Present for less than 2 weeks & is usually due to: </li></ul></ul></ul><ul><ul><ul><ul><li>Infectious agent (most common cause) (usually from fecal-oral) </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Bacterial toxin </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Drugs </li></ul></ul></ul></ul><ul><ul><ul><li>Types of Acute Diarrhea </li></ul></ul></ul><ul><ul><ul><ul><li>Non-inflammatory </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Inflammatory </li></ul></ul></ul></ul>
  42. 42. Acute Diarrhea <ul><li>Non-inflammatory </li></ul><ul><ul><li>Watery </li></ul></ul><ul><ul><li>Nonbloody </li></ul></ul><ul><ul><li>Abd. Cramps </li></ul></ul><ul><ul><li>Bloating </li></ul></ul><ul><ul><li>Nausea-vomiting </li></ul></ul><ul><li>All of these suggest a small bowel enteritis that disrupts the normal absorption & secretory process of the small bowel </li></ul><ul><li>The diarrhea can be voluminous & cause electrolyte imbalance. </li></ul><ul><li>Inflammatory </li></ul><ul><ul><li>Fever </li></ul></ul><ul><ul><li>Bloody diarrhea (dysentery) </li></ul></ul><ul><li>This indicates colonic tissue damage caused by invasion of: </li></ul><ul><ul><li>Bacteria (infectious process) </li></ul></ul><ul><ul><li>Toxins </li></ul></ul><ul><li>These organisms that are different from the non-inflammatory organisms involve the colon & the diarrhea is smaller volume & associated with LLQ pain </li></ul><ul><ul><li>Fecal Leukocytes (WBC’s) can be present </li></ul></ul><ul><ul><li>Pearl:Don’t give anti-diarrheals </li></ul></ul>
  43. 43. Causes of acute diarrhea Non-inflammatory <ul><li>Viral </li></ul><ul><ul><li>Norwalk virus </li></ul></ul><ul><ul><li>Rotavirus </li></ul></ul><ul><li>Protozoal </li></ul><ul><ul><li>Giardia lamblia </li></ul></ul><ul><ul><li>Cryptosporidium </li></ul></ul><ul><li>Bacterial </li></ul><ul><ul><li>Preformed enterotoxin </li></ul></ul><ul><ul><ul><li>Staphylococcus aureus </li></ul></ul></ul><ul><ul><ul><li>Bacillus cereus </li></ul></ul></ul><ul><ul><ul><li>Clostridium perfingens </li></ul></ul></ul><ul><li>Intra-intestinal enterotoxin production </li></ul><ul><ul><li>E coli (enterotoxigenic) </li></ul></ul><ul><ul><li>Vibrio cholera </li></ul></ul><ul><li>New Medication </li></ul><ul><ul><li>Including Antibiotic use </li></ul></ul><ul><ul><ul><li>C. difficile </li></ul></ul></ul><ul><ul><ul><ul><li>severe cases causing pseudomembranous colitis </li></ul></ul></ul></ul><ul><li>Laxative use </li></ul><ul><li>Fecal Impaction </li></ul><ul><li>Pancreatic Insufficiency </li></ul><ul><li>Malabsorption </li></ul>
  44. 44. Causes of acute diarrhea Inflammatory <ul><li>Viral </li></ul><ul><ul><li>Cytomegalovirus </li></ul></ul><ul><li>Bacterial </li></ul><ul><ul><li>Cytotoxin production </li></ul></ul><ul><ul><ul><li>E coli (Enterohemorrhagic) </li></ul></ul></ul><ul><ul><ul><li>Vibrio parahaemolyticus </li></ul></ul></ul><ul><ul><ul><li>Clostridium difficile </li></ul></ul></ul><ul><ul><li>Mucosal Invasion </li></ul></ul><ul><ul><ul><li>Shigella </li></ul></ul></ul><ul><ul><ul><li>Salmonella sp. </li></ul></ul></ul><ul><ul><ul><li>Enteroinvasive E coli </li></ul></ul></ul><ul><ul><ul><li>Aeromonas </li></ul></ul></ul><ul><ul><ul><li>Yersinia enterocolitica </li></ul></ul></ul><ul><ul><ul><li>Plasmodium (Malaria) </li></ul></ul></ul><ul><ul><li>Bacterial Proctitis </li></ul></ul><ul><ul><ul><li>Chlamydia </li></ul></ul></ul><ul><ul><ul><li>N. gonorrhoeae </li></ul></ul></ul><ul><li>Protozoal </li></ul><ul><ul><li>Entamoeba histolytica </li></ul></ul><ul><li>Intestinal ischemia </li></ul><ul><li>Inflammatory bowel disease </li></ul><ul><li>Radiation Colitis </li></ul>
  45. 45. Diarrhea History <ul><li>Onset </li></ul><ul><li>Duration </li></ul><ul><li>Severity (fever, bloody, abd. Pain) </li></ul><ul><li>Travel </li></ul><ul><li>Food ingestion </li></ul><ul><li>Exposure to sick contacts </li></ul><ul><li>Social </li></ul><ul><li>Medications </li></ul><ul><li>FH of Crohn’s ds. or UC </li></ul><ul><li>Diarrhea-constipation suggest IBS </li></ul><ul><li>Excessive flatus c diarrhea indicates CHO diarrhea which ceases c fasting </li></ul><ul><li>Nocturnal diarrhea indicates autonomic neuropathy or anal sphincter ds. </li></ul><ul><li>Large volumes indicate sm. Bowel </li></ul><ul><li>Small volumes are usually left colon c tensmus </li></ul><ul><li>Associated c arthritis consider Whipples or IBD </li></ul>
  46. 46. Physical Examination <ul><li>Appearance and mental status </li></ul><ul><li>Mucous membranes and skin turgor </li></ul><ul><li>BP (hypotension) </li></ul><ul><li>Scars </li></ul><ul><li>Abdominal Exam </li></ul><ul><ul><li>Peritoneal signs </li></ul></ul><ul><ul><li>Localized tenderness </li></ul></ul><ul><ul><li>Masses </li></ul></ul><ul><ul><li>Bruits-carcinoids &/or renal artery stenosis </li></ul></ul><ul><ul><li>Rectal exam is needed </li></ul></ul><ul><ul><ul><li>Sphincter tone- Neurogenic ->DM </li></ul></ul></ul><ul><ul><ul><li>Blood on stool & appearance </li></ul></ul></ul>
  47. 47. Diagnostic Studies for Acute Diarrhea <ul><li>Stool exam for blood or WBC’s </li></ul><ul><ul><li>In any patient with fever, abd pain, tenesmus, dehydration, & diarrhea >3 days </li></ul></ul><ul><li>Stool culture </li></ul><ul><ul><li>On all those with WBC’s and blood, mucous in stool with fever, abd pain (rectal swab if no stool present) </li></ul></ul><ul><li>Stool for Ova & Parasites </li></ul><ul><ul><li>For severe or persistent diarrhea (if + do HIV test) </li></ul></ul><ul><li>Blood test </li></ul><ul><ul><li>CBC c eosinophil count, Electrolytes, calcium, glucose, blood cultures for high fevers, HIV, Vit B12 depending on symptoms and character of diarrhea </li></ul></ul><ul><li>ELISA </li></ul><ul><ul><li>For Giardi lamblia (ameba titers), E. coli, C. Difficile (as a cause of pseudomembranous colitis) if from day care center, or loosing weight, traveling, HIV for immunosuppresed. </li></ul></ul>
  48. 48. Management issues <ul><li>Watch for dehydration and check for electrolyte disturbances (metabolic acidosis, hypokalemia), a common and preventable cause of death in underdeveloped areas. </li></ul><ul><li>Do a rectal exam, check for occult blood in stool, and examine stool for bacteria, ova and parasites, fat content (steatorrhea), and WBC’s </li></ul><ul><li>If the cause is not obvious, a trial of NPO status is helpful to see if the diarrhea stops. </li></ul><ul><li>If the pt has a h/o antibiotic usage c in 2 wks think Clostridium difficile and test the stool for toxin. If the test is positive, treat with metronidazole (or vancomycin). </li></ul><ul><li>Remember DM (diabetic diarrhea), factitious diarrhea (secret laxative abuse), hyperthyroidism, and colorectal cancer as causes of diarrhea. </li></ul>
  49. 49. Treatment <ul><li>Supportive therapy is sufficient for most patients with viral or bacterial diarrhea </li></ul><ul><li>Antibiotics may be indicated for patients with severe diarrhea and systemic symptoms (e.g., Shigella, Campylobacter, severe cases of C. difficile ). </li></ul><ul><li>Treatment of the underlying cause is required for noninfectious diarrhea. </li></ul>
  50. 50. Treatment for acute diarrhea <ul><li>1. Nonspecific Antidiarrheals </li></ul><ul><ul><li>These are overused </li></ul></ul><ul><ul><li>Unnecessary in most cases of diarrhea </li></ul></ul><ul><ul><li>In chronic diarrhea they are not a substitute for treatment of the underlying pathology. </li></ul></ul><ul><ul><li>Examples- </li></ul></ul><ul><ul><ul><li>Paregoric </li></ul></ul></ul><ul><ul><ul><li>Loperamide (Imodium ) </li></ul></ul></ul><ul><ul><ul><li>Diphenoxylate (Lomotil ) has some atropine also </li></ul></ul></ul><ul><ul><li>** These agents may cause Toxic Megacolon with patients that have invasive infections </li></ul></ul>
  51. 51. Treatment for acute diarrhea (cont.) <ul><li>2. Bulk forming agents </li></ul><ul><li>3. Absorbents: </li></ul><ul><ul><li>Kaopectate after each BM </li></ul></ul><ul><ul><li>Aluminum Hydroxide </li></ul></ul><ul><li>4. Opiod Agents: should be used cautiously in patients with asthma, COPD, prostatic hypertophy, and acute angle closure glaucoma. </li></ul><ul><ul><li>Paregoric (tinc of opium) (after each BM) </li></ul></ul><ul><ul><li>Codeine </li></ul></ul><ul><ul><li>Diphenoxylate (a meperidine conger) Contraindicated in liver ds. </li></ul></ul><ul><ul><li>**Do not use if there is fever, bloody diarrhea, or any evidence of toxicity!!** </li></ul></ul>
  52. 52. Treatment for acute diarrhea <ul><li>5. Antisecretory agents: </li></ul><ul><ul><li>Bismuth Subsalicylate (Pepto-Bismol) </li></ul></ul><ul><li>6. Anticholinergics: (offer no value) </li></ul><ul><li>7. Antimicrobial agents: </li></ul><ul><ul><li>**Do stool cultures first </li></ul></ul><ul><ul><li>Ova and Parasite studies </li></ul></ul><ul><li>8. Somatostatin: used in severe diarrhea which is refractory to any therapy. Used in carcinoid syndrome or VIPomas. (IV or SC.) </li></ul>
  53. 53. Treatment for acute diarrhea <ul><li>9. Special Therapies: </li></ul><ul><ul><li>Clonidine is used for withdrawal of diarrhea in patient on opiates (usually used for HTN) </li></ul></ul><ul><ul><li>Indocin is used for patients with radiation enteritis (a prostaglandin inhibitor) </li></ul></ul><ul><ul><li>Traveler’s Diarrhea (all started one week prior or 2 days post travel) </li></ul></ul><ul><ul><ul><li>Pepto-Bismol </li></ul></ul></ul><ul><ul><ul><li>Tetracycline/ Doxycycline </li></ul></ul></ul><ul><ul><ul><li>Bactrim </li></ul></ul></ul>
  54. 54. Chronic Diarrhea <ul><li>Diarrhea >2-3 weeks, and usually progressively debilitating </li></ul><ul><li>The goal for chronic diarrhea is to make the dx quickly </li></ul><ul><li>80% diagnosed by H&P </li></ul>
  55. 55. Mechanisms of Chronic Diarrhea <ul><li>1. Osmotic load : increase in amounts of poorly absorbable osmotic active solutes in the gut of the lumen. </li></ul><ul><ul><li>Examples: </li></ul></ul><ul><ul><ul><li>#1 Lactose intolerance </li></ul></ul></ul><ul><ul><ul><li>#2 Milk of magnesia </li></ul></ul></ul><ul><ul><ul><li>Infectious gastroenteritis </li></ul></ul></ul><ul><ul><ul><li>Lactulose </li></ul></ul></ul><ul><li>2. Excessive secretion ( secretory ): increase CL & H2O w/o sodium resorption: </li></ul><ul><ul><li>Examples: </li></ul></ul><ul><ul><ul><li>Zollinger Ellison syndrome </li></ul></ul></ul><ul><ul><ul><li>Seratonins (carcinoid) </li></ul></ul></ul><ul><ul><ul><li>Staph toxin </li></ul></ul></ul>
  56. 56. Mechanisms of Chronic Diarrhea (cont.) <ul><li>3. Exudation of protein ( Inflammatory ) </li></ul><ul><ul><li>Idiopathic (Crohn’s ds.) </li></ul></ul><ul><ul><li>Infectious (Shigella, Salmonella, Campylobacter) </li></ul></ul><ul><ul><li>Ischemic </li></ul></ul><ul><ul><li>Vasculitis (blood & mucous in stool) </li></ul></ul><ul><li>4. Altered intestinal Motility (Irritable bowel syndrome) </li></ul>
  57. 57. Screening test for chronic diarrhea <ul><li>Blood </li></ul><ul><ul><li>CBC </li></ul></ul><ul><ul><li>Sedimentation rate </li></ul></ul><ul><ul><li>Albumin </li></ul></ul><ul><ul><li>Electrolytes </li></ul></ul><ul><ul><li>Prothrombin time (malabsorption) </li></ul></ul><ul><ul><li>Alkaline phosphatase </li></ul></ul><ul><ul><li>Serum Iron (Fe) </li></ul></ul><ul><ul><li>Folate & Vitamin B12 (c diarrhea and alt. Mental status) </li></ul></ul><ul><ul><li>Carotene </li></ul></ul><ul><li>Stool </li></ul><ul><ul><li>Appearance of stool </li></ul></ul><ul><ul><li>Occult blood test </li></ul></ul><ul><ul><li>Ova-Parasites </li></ul></ul><ul><ul><li>Stool fat </li></ul></ul><ul><li>Proctoscopy with biopsy </li></ul>
  58. 58. Treatment for chronic diarrhea <ul><li>Paregoric </li></ul><ul><li>Imodium </li></ul><ul><li>Lobitol </li></ul><ul><li>Metamucil </li></ul><ul><li>Kaopectate </li></ul><ul><li>Amphigel </li></ul><ul><li>**Note in infectious diarrhea  slowing motility can cause Toxic Megacolon  death from necrosis of bowel. </li></ul>
  59. 59. Diarrhea Types <ul><li>Secretory </li></ul><ul><ul><li>Bowel secretes fluid b/c of bacterial toxins </li></ul></ul><ul><ul><li>Large volume watery stools </li></ul></ul><ul><ul><ul><li>Danger of dehydration </li></ul></ul></ul><ul><ul><li>Persists with fasting </li></ul></ul><ul><ul><li>Cholera </li></ul></ul><ul><ul><li>Some strains of E coli </li></ul></ul><ul><ul><li>Ileal resection (bile acids) </li></ul></ul><ul><ul><li>Carcinoid </li></ul></ul><ul><ul><li>VIP secreting tumors (pancreatic islet cell tumor) </li></ul></ul><ul><li>Osmotic </li></ul><ul><ul><li>Non absorbable solutes remain in the bowel, where they retain water </li></ul></ul><ul><ul><li>Bulky, greasy stools </li></ul></ul><ul><ul><li>Improves with fasting </li></ul></ul><ul><ul><li>Lactase deficiency </li></ul></ul><ul><ul><li>Pancreatic insufficiency </li></ul></ul><ul><ul><li>Short bowel syndrome </li></ul></ul><ul><li>Inflammatory </li></ul><ul><ul><li>Frequent but small stools </li></ul></ul><ul><ul><li>Blood and/or pus </li></ul></ul><ul><ul><li>Inflammatory bowel ds </li></ul></ul><ul><ul><li>Irradiation </li></ul></ul><ul><ul><li>Shigella, amebiasis </li></ul></ul><ul><li>Dysmotility </li></ul><ul><ul><li>Diarrhea alternating with constipation </li></ul></ul><ul><ul><li>Irritable bowel syndrome </li></ul></ul><ul><ul><li>Diabetes mellitus </li></ul></ul>
  60. 60. Chronic Diarrhea Classification <ul><li>Inflammatory - Inflammatory bowel ds., radiation colitis </li></ul><ul><li>Systemic - any illness can cause diarrhea as a systemic symptom (hyperthyroid, zollinger-ellison, flu) </li></ul><ul><li>Osmotic - nonabsorbable solutes remain in the bowel, where they retain water (e.g. lactose or other sugar intolerances). When the person stops eating the offending substances NPO, the diarrhea stops. </li></ul><ul><li>Secretory - bowel secretes fluid b/c of bacterial toxins (cholera, some strains of E coli), VIPoma (pancreatic islet cell tumor), or bile acids (p ileal resection). Diarrhea continues with NPO status. </li></ul><ul><li>Malabsoption - (e.g., celiac sprue, Crohn’s ds.) In pt’s c celiac sprue, look for dermatitis herpetiformis, and stop gluten in the diet. Diarrhea stops c NPO. </li></ul><ul><li>Exudative - inflammation in bowel mucosa causes seepage of fluid; classically from inflammatory bowel ds. or cancer </li></ul><ul><li>Altered Intestinal Motility- after bowel resection or medications that interfere with bowel function </li></ul><ul><li>Factitious - secret laxative abuse (often by medical personnel) </li></ul>
  61. 61. Chronic Diarrhea <ul><li>Chronic diarrhea or recurrent diarrhea should be based on etiology & pathophysiology of the disease process. </li></ul><ul><li>When there is difficulty in making the diagnosis an empiric trial of diet restriction is necessary. </li></ul><ul><ul><li>Lactose </li></ul></ul><ul><ul><li>Gluten (protein in breads) </li></ul></ul><ul><ul><li>Reduction of long chain fatty acids </li></ul></ul><ul><li>Use of pancreatic enzymes </li></ul><ul><li>Metronidazole </li></ul><ul><li>When all else fails use opiates </li></ul>
  62. 62. Pearls/ Review <ul><li>Antidiarrheals often unnecessary (opiods: loperamide) b/c they may actually prolong Salmonella or Shigella infection! </li></ul><ul><li>If chronic or patient very ill (fever, bloody diarrhea): get stool exam for WBC’s, O&P’s, stool cx, C. difficile toxin and LFT’s. </li></ul>
  63. 63. Pearls (cont.) <ul><li>AID’s patients: diarrhea is often due to Cryptosporidium, Isospora or CMV </li></ul><ul><li>Diarrhea of any cause may lead to transient lactase deficiency (advise patient to avoid milk) </li></ul><ul><li>Bismuth subsalicylate (Pepto-Bismol) may prevent infection with enterotoxin producing E. coli. Great for travelers to exotic countries. </li></ul>
  64. 64. Pearls <ul><li>Diarrhea in elderly patients can indicate an obstruction or fecal impaction. </li></ul><ul><li>Acute Diarrhea: Lg amts. of stool  Small bowel Sm amts. of stool  Lg bowel </li></ul><ul><li>Gastroenteritis symptoms  #1. abd. pain #2. diameter </li></ul><ul><li>Celiac sprue  Gluten sensative enteropathy  proximal small bowel </li></ul>
  65. 65. Pearls <ul><li>In >90% of cases, acute diarrhea is mild and self-limiting, and diagnostic investigation is unnecessary. </li></ul><ul><li>Prompt sigmoidoscopy for severe proctitis (tenesmus, discharge, rectal pain) or suspected C. difficile colitis, ulcerative colitis, or ischemic colitis </li></ul><ul><li>When traveling 4 “P’s”, Pepto-bismol, and eat only peeled, packaged, and piping hot foods. </li></ul>
  66. 66. Review <ul><li>Infectious: noninflammatory (nonbloody) </li></ul><ul><li>Viruses: Norwalk virus, rotavirus, adenoviruses, astrovirus, coronavirus </li></ul><ul><li>Preformed toxin (food poisoning): Staphylococcus aureus , Bacillus cereus , Clostridium perfringens </li></ul><ul><li>Toxin production: enterotoxigenic E. coli , Vibrio cholerae , Vibrio parahaemolyticus </li></ul><ul><li>Protozoa: Giardia lamblia , Cryptosporidium , Cyclospora , Isospora </li></ul>
  67. 67. Review <ul><li>Infectious: invasive or inflammatory </li></ul><ul><li>Shigella , Salmonella , Campylobacter , enteroinvasive E. coli , E. coli O157:H7, Yersinia enterocolitica , Clostridium difficile (e.g., pseudomembranous colitis), Entamoeba histolytica , Neisseria gonorrhoeae , Listeria monocytogenes </li></ul>
  68. 68. Pearl <ul><li>Bloody Diarrhea DDx </li></ul><ul><li>Shigella , </li></ul><ul><li>Salmonella , </li></ul><ul><li>Campylobacter , </li></ul><ul><li>enteroinvasive E. coli , ( E. coli O157:H7), </li></ul><ul><li>Yersinia enterocolitica , </li></ul>

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