Successfully reported this slideshow.
We use your LinkedIn profile and activity data to personalize ads and to show you more relevant ads. You can change your ad preferences anytime.

Diarrhoea by Dr Peter Soltau 2014


Published on


Published in: Health & Medicine
  • Be the first to comment

Diarrhoea by Dr Peter Soltau 2014

  1. 1. The clinical features, pathology, microbiology and ER management of acute diarrheal diseases, including HIV-related gastrointestinal infections Dr. Peter Andre Soltau
  2. 2. Background / Incidence • The W.H.O reports > 3 million episodes of diarrhea annually and estimates > 2.2 million diarrheal deaths occur mainly in children, especially in low- and middle-income countries • Diarrheal diseases represent one of the five leading causes of death worldwide • Commonly called the "nuisance disease"
  3. 3. Definitions • Acute primary diarrhea defined as 3 or more loose/ watery/ diarrheal stools in a 24-hour period • Duration: • Acute < 14 days • Persistent > 14 days • Chronic > 30 days • Dysentery - frequent passage of small volume stools assoc. blood, mucus, abdominal cramping and tenesmus
  4. 4. Severe Diarrhea - 4 or more stools per day for 3 or more days associated with [abdominal symptoms(cramps, nausea, vomiting, tenesmus) or systemic symptom (fever, malaise, dehydration)].
  5. 5. Classifying Diarrhea • Secretory vs Osmotic • Infectious vs Non-Infectious • Inflammatory vs Non Inflammatory
  6. 6. Secretory diarrhea • Due to abnormal electrolyte transport across the intestinal epithelial cells • Increased secretion and/or decreased absorption result • The diarrhea is not related to the intestinal contents and therefore typically does not stop with fasting. • Infection (e.g., cholera) is the most common cause of secretory diarrhea • The fluid losses can be enormous.
  7. 7. Osmotic diarrhea • The presence of nonabsorbable solute exerts an osmotic pressure effect across the intestinal mucosa, resulting in excessive water output • Stops during fasting • The offending molecule is usually a carbohydrate or divalent ion. • Common examples include mannitol or sorbitol, epson salt (MgSO4) and some antacids (MgOH2).
  8. 8. Malabsorption • Inability to absorb certain carbohydrates is the most common deficit, but it can result virtually from any type of malabsorption. • E.g. lactose intolerance: a deficiency in the brush border enzyme lactase.
  9. 9. Etiology • Infectious: • Viruses • Norovirus, rotavirus, adenoviruses, astrovirus, and others • Bacteria • Salmonella, campylobacter, shigella, enterotoxigenic E. coli, C. difficile, vibrio species and others • Protozoa • Cryptosporidium, giardia l., cyclospora, entamoeba h., and others
  10. 10. Etiology • Dietary Disturbances: • Overfeeding, food allergy, starvation stools • Anatomic Abnormalities • Intussusception, hirschsprung, partial obstruction, appendicitis, blind loop syndrome, short bowel syndrome • Inflammatory Bowel disease • Malabsorption or secretory diseases • Cystic fibrosis, celiac disease, disaccharidase deficiency • Systemic Diseases • Immunodificiency, endocrinopathy (CAH, thyroid disorders) • Miscellaneous • Antibiotic associated, secondary lactase deficiency, irritable colon syndrome, toxins, HUS
  11. 11. Pathology - Infectious • Pathogenic organisms must be swallowed, they must survive the acid in the stomach, intestinal immunity, motility, mucus, and the resident micro flora, then colonize the small bowel and stick to the enterocytes. They then produce their harmful effects by one of several mechanisms
  12. 12. Viral Pathogens • Invade & destroy the small intestinal mucosa villous epithelium • Loss of mature absorptive cells • Regeneration of poorly differentiated intestinal epithelial cells • Impaired salt and water absorption • Carbohydrate malabsorption leading to osmotic diarrhea
  13. 13. Bacterial Pathogens • Invasive: • Adhere to mucosal cells followed by invasion and multiplication, initiating an acute mucosal inflammatory reaction, leading to ulceration and synthesis of a variety of secretagogues. esp. in large intestine • E.g. Shigella, Salmonella, Yersinia enterocolitica, campylobacter jejuni, vibrio parahemolyticus • Cytotoxic: • Elaboration of cytotoxins which can either inhibit protein synthesis or induce secretion of inflammatory mediators causing cell death and hence decrease the intestinal absorptive surface area • E.g. Shigella, E.coli, clostridium difficile
  14. 14. Bacterial Pathogens • Toxigenic • Colonize the small intestines and secrete enterotoxins which bind mucosal receptors and increase an intracellular mediator altering salt and water transport (mucosal integrity is unchanged) • E.g. Shigella, E.coli, Yersinia E., Vibrio cholerae • Adherent: • Colonize and adhere to intestinal surface of small and large intestine, indenting the surface and flattening the microvilli, thereby decreasing the surface area • E.g. E. coli
  15. 15. Microbiology • Laboratory testing: • Routine testing for specific pathogens is not recommended • Reserve laboratory testing and stool cultures for select circumstances. • Criteria vary but often include bloody diarrhea, weight loss, diarrhea leading to dehydration, fever, neurologic involvement, sudden onset of severe abdominal pain, persistent (> 7 days) diarrhea, or possible community-acquired diarrhea, traveler’s diarrhea, or nosocomial diarrhea
  16. 16. ED management
  17. 17. ED Management History Of Present Illness • Type and volume of stools: • Associated symptoms: nausea, vomiting, abdominal pain, fever, and tenesmus • • • • • Character and location of any abdominal pain Duration of symptoms Weight loss Indicators of dehydration Epidemiological risk factors • Recent diet, ingestion of seafood, raw or undercooked meat, eggs, or milk products • Recent foreign travel • Lake or stream swimming • Visits to a farm • Ill contacts, • Group living arrangements (e.g., nursing home, college dormitory) or day care attendance
  18. 18. • Past Medical History • Comorbidities • Immunosuppression • Crohn’s disease or ulcerative colitis • Medications • prescription, over-the-counter, and herbal preparations • laxatives, antibiotics, magnesium- or calcium-containing antacids. • alpha-glucosidase inhibitors (e.g., acarbose, miglitol) • Artificial sweeteners containing sorbitol or mannitol • Enteral tube feedings
  19. 19. • Social History • Occupational history (veterinarian, food handler, or day care center or nursing home employee) • Sexual preference • Inquire about alcohol and drug use
  20. 20. Indications for diagnostic evaluation • Profuse watery diarrhea with signs of hypovolemia • Passage of many small volume stools containing blood and mucus • Bloody diarrhea • Temperature ≥38.5ºC (101.3ºF) • Passage of ≥6 unformed stools per 24 hours or a duration of illness >48 hours • Severe abdominal pain • Recent use of antibiotics or hospitalized patients • Diarrhea in the elderly (≥70 years of age) or the immunocompromised
  21. 21. Tests • Blood Tests • CBC: unnecessary in most • Chem Path: unnecessary in most • Fecal Leukocyte/Lactoferrin Testing: • Community-acquired or traveler’s diarrhea, nosocomial diarrhea, and diarrhea persisting more than seven days have been suggested
  22. 22. • Stool Culture • the yield on routinely obtained stool cultures is low (1 -5%) • Indicated : • • • • • history of bloody stools (grossly bloody or heme-positive stools) stools containing leukocytes or lactoferrin; immunocompromised patients; fever higher than 38.5°C (101.3°F); systemic illness or an illness that is clinically severe or persistent; patients with severe abdominal pain. • Stool testing for Parasites • diarrhea lasting more than 14 days • immunocompromised • not responded to antimicrobial therapy
  23. 23. ED Management
  24. 24. HIV/ AIDS • Prone to diarrheal Illnesses, in developing world up to 100% • Increased risk due to: • Develop enteric infections from a variety of unusual viral, parasitic, protozoal, and bacterial organisms • Malignancies (lymphoma/Kaposi's sarcoma) • Multiple course of antibiotics – antibiotic associated diarrhea • Stool culture should be done, along with C. difficile toxin and ova and parasite • If negative consider endscopic investigation
  25. 25. Treatment • Rapidly assess hydration status, risk factors for likely bacterial pathogen, and need for symptomatic relief • Rehydration - IV VS ORT • Diarrhea relief include loperamide, diphenoxylate, and bismuth subsalicylate
  26. 26. Oral rehydration Therapy • Directed at preventing or treating dehydration, replacing ongoing fluid loss, and meeting nutritional needs • Correct fluid deficit over 4 hours • 50 – 100mls of ORS/ kg • Aim for 30mls of ORS/kg per hour • Pedialyte, Lytren, and Rehydrolyte
  27. 27. IV Fluids • Indicated for severe dehydration, hemodynamic instability, altered mental status • 20 ml/kg bolus in children
  28. 28. Controversial Treatments • Probiotics – microorganisms used to colonize the intestine and treat or prevent diarrhea, found to reduce duration on average 0.7 days, and frequency by 1.6 per day • Zinc – RCT suggests a reduction in duration and severity of acute and persistent diarrhea, however more likely to vomit • Ramoplanin – a new antibiotic in Phase II development for C. difficile associated diarrhea
  29. 29. Role of Antibiotics • Empiric antibiotics should be considered for patients: • • • • with acute dysentery moderate-to-severe traveler’s diarrhea Diarrhea lasting longer than two and a half days fever greater than 38.5°C (101.3°F) plus either leukocyte-, lactoferrin, or hem occult-positive stools • Fluoroquinolones for adults and trimethoprimsulfamethoxazole (TMP-SMX) for children are reasonable
  30. 30. Disposition / Follow Up • Decision relies heavily on physician judgment • Most commonly – clinically stable, benign exam and low risk for complications – safely discharged with follow up • Moderate or severe dehydration, intractable or bilious vomiting, surgical cause of vomiting, neurological abnormalities, large ongoing losses, poor social support are candidates for admission • Special consideration for patients with diagnostic dilemma, extremes of age, immunocompromised, or multiple or severe comorbidities • Discharge instructions are mandatory both verbal and written
  31. 31. Transmission Prevention • Good hand washing hygiene • Travel Precautions • Immunization - Rotavirus vaccines • Patient & family education
  32. 32. Summary • The role of the emergency physician is to exclude serious illness, ensure patient stability, begin an investigation to exclude infectious causes of diarrhea, and provide timely referral for further evaluation • This diagnostic evaluation usually exceeds the scope of most ED capabilities • If there is a doubt about the diagnosis, ED observation and repeated examinations can be helpful. • Patients warranting a greater level of concern are the very young, the elderly, immunocompromised individuals, those with major comorbidities, and those with unusual or atypical presentations