Acute Diarrhea

Aka: Acute Diarrhea, Diarrhea

1. See Also
   1. Gastroenteritis
   2. Pediatric Diarrhea
   3. Chronic Diarrhea
   4. Traveler's Diarrhea Management
   5. Traveler's Diarrhea Prophylaxis
   6. Traveler's Diarrhea Prevention
   7. Waterborne Illness
   8. Foodborne Illness
   9. Diarrhea Management in Children
   10. Management of Moderate Diarrhea under age 2 years
   11. Management of Mild Diarrhea under age 2 years
   12. Pediatric Diarrhea Fluid Replacement
   13. Oral Rehydration Solution
2. Definition
   1. Gastroenteritis
      1. Inflammation of the gastrointestinal tract (Stomache and Small Intestine)
      2. Typical presentation is Vomiting followed by Diarrhea
   2. Diarrhea
      1. Frequent liquid stools
         1. Adults: >200 g/day of stool (at least 3 Bowel Movements daily)
         2. Children: >20 g/kg/day of stool
      2. Timing
         1. Acute Diarrhea: Duration <3 weeks
         2. Chronic Diarrhea: Duration >3 weeks
            1. Chronic Fatty Diarrhea
            2. Chronic Inflammatory Diarrhea
            3. Chronic Watery Diarrhea
3. Pathophysiology
   1. Small Intestine secretes and reabsorbs 10 liters/day
      1. Extrusion of Chloride from villus crypt cell (cAMP)
      2. Absorption at villus tip
   2. Diarrhea classified as:
      1. Watery Diarrhea
         1. Secretory Diarrhea
            1. Stool Sodium high (60-120 meq/L)
            2. Hypersecretion by intestinal crypts
         2. Osmotic Diarrhea (osmotic loss of free water)
            1. Stool Sodium low (30-40 meq/L)
            2. Associated with ingestion of non-digestable agents that draw water from the bowel wall
      2. Inflammatory Diarrhea
         1. Stool with pus or blood present
      3. Fatty Diarrhea (Malabsorption)
         1. Large greasy, frothy pale stools with foul odor
   3. Serum Electrolyte loss
      1. Serum Bicarbonate loss
      2. Serum Potassium loss
4. Causes: Acute Vomiting (Gastroenteritis)
   1. See Vomiting Causes
   2. See Foodborne Illness
   3. Severe Emergency Department cases in adults
      1. Norovirus (26%)
      2. Rotavirus (18%)
      3. Salmonella (5.3%)
      4. Bresee (2012) J Infect Dis 205 (9): 1374-81
5. Causes: Acute Diarrhea
   1. Infectious Diarrhea Causes
      1. See Infectious Diarrhea Causes
      2. Viruses (30-40% of episodes)
         1. Norovirus is most common viral Diarrhea cause
      3. Bacteria and Parasites (20-30% of episodes)
         1. Campylobacter jejuni (most common bacteria)
         2. Salmonella
         3. Shigella
         4. E. coli 0157:H7 (30% of infectious bloody stool)
      4. Other Infectious Disease
         1. Otitis Media
         2. Sepsis
         3. Sexually Transmitted Disease
   2. Noninfectious Causes
      1. See Osmotic Diarrhea
      2. See Secretory Diarrhea
      3. Common Causes
         1. Intestinal Obstruction
         2. Toxic Ingestions
         3. Inflammatory and Allergic Conditions
6. Risk Factors
   1. Recent travel to endemic area
      1. See Traveler's Diarrhea
      2. Travel to a developing area is associated with a 25% chance of developing Diarrhea
      3. Those with Diarrhea in a developing area have an 80% chance of bacterial Diarrhea
   2. Foodborne Illness
   3. Waterborne Illness
      1. Hiking in wilderness areas (especially drinking from mountain streams)
      2. Consider Giardia, Entamoeba histolytica, Cryptospordium
   4. Day care exposure
      1. Consider Giardia
   5. High-risk sexual behavior
      1. See Diarrhea from Sexually Transmitted Disease
   6. Antibiotic use within 6 months (Clostridium difficile)
   7. Immunosuppression
7. History: Diarrhea
   1. See Vomiting
   2. Stool size
      1. Frequent small volume stools
         1. Large Bowel
      2. Frequent large volume stools
         1. Small Bowel
   3. Blood or mucous present in stool
      1. Inflammatory Diarrhea
   4. Provocative agents
      1. Foods
      2. Milk
      3. Sorbitol
      4. New medications
   5. Associated findings
      1. Fever
      2. Abdominal Pain
      3. Paresthesias (consider Neurotoxin such as Ciquatera toxin)
   6. Risks
      1. Recent antibiotic use
      2. Travel (including wilderness)
      3. Immunosuppression or Chemotherapy
      4. Thyroid disease
      5. HIV Infection
8. Exam
   1. See Vomiting
   2. Eye Exam
      1. Episcleritis
         1. Consider Inflammatory Bowel Disease (Reiters Syndrome)
   3. Thyroid exam
   4. Skin Exam
      1. Erythema Nodosum
         1. Consider Inflammatory Bowel Disease
   5. Abdominal exam
      1. Benign Abdomen despite severe pain
         1. Consider Mesenteric Ischemia (especially if grossly bloody stool)
      2. Bowel sounds
         1. Hyperactive bowel sounds
            1. Typical in Diarrheal illness
         2. Hypoactive bowel sounds
            1. Bowel Obstruction
   6. Rectal exam
      1. Anal Fissures
         1. Consider Inflammatory Bowel Disease
      2. Bloody stool (occult or gross)
         1. Consider Inflammatory Bowel Disease
         2. Consider Mesenteric Ischemia
9. Evaluation: Precautions
   1. See specific tests for indications
   2. Labs are expensive and do not alter management in most cases (in the United States)
      1. Directed history and exam are most useful
   3. Labs not routinely performed
      1. Fecal Leukocytes
         1. Stool Guaiac has the same Positive Predictive Value to identify bacterial Diarrhea
         2. Bloody stool without Fecal Leukocytes suggests E coli 0157:H7 or Entamoeba histolytica
      2. Stool Culture
         1. Expensive and very low test senstitivity (5%)
         2. Only indicated for toxic appearance, prolonged Diarrhea >4 days, blood or pus in stool, immunocompromised patients
      3. Ova and Parasites
         1. Low yield (requires multiple samples)
         2. Specific Stool Parasite antigens are preferred with better accuracy
         3. Consider for travel to developing countries, watery Diarrhea >7 days
   4. Labs performed as indicated
      1. Clostridium difficile Toxin
      2. Parasite antigens
         1. Giardia antigen
         2. Cryptosporidium antigen
      3. Medication levels
         1. Theophylline level
         2. Lithium level
      4. Serum electrolytes
         1. Normal in 99% of young, healthy adults with Acute Gastroenteritis in the first 24 hours
            1. Olshaker (1989) Ann Emerg Med 18(3): 258-60
         2. Consider in prolonged Diarrhea, dehydration requiring IV fluids, toxic or ill appearance, or comorbid condition
10. Evaluation: Labs
    1. See Labs and Endoscopy below
    2. Community-acquired, Traveler's Diarrhea or Dysentery
       1. Stool Cultures
          1. Salmonella
          2. Shigella
          3. Campylobacter
          4. Escherichia coli 0157:H7 (STEC: Shiga Toxin E coli)
             1. Shiga Toxin (if bloody stool)
             2. Avoid antimicrobial agents
       2. Clostridium difficile Toxins
          1. Indicated for recent antibiotics or Chemotherapy
       3. Consider antibiotic coverage (if not STEC)
          1. Quinolone if suspected Shigellosis
          2. Macrolide for suspected Campylobacter
    3. Nosocomial Diarrhea (after 3 days of hospitalization)
       1. Clostridium difficile Toxins
       2. Consider community acquired labs as above
       3. Discontinue antibiotics if possible
       4. Consider Flagyl if worsens or persists
    4. Persistent Diarrhea >7 days (esp. immunocompromised)
       1. Fecal Leukocytes or Fecal Lactoferrin
       2. Parasitic Infection evaluation
          1. Giardia
          2. Cryptosporidium
          3. Cyclospora
          4. Isospora belli
       3. Opportunistic infection in HIV positive patients
          1. Community acquired labs as above
          2. Microsporidia
          3. Mycobacterium Avium Intracellulare Complex
11. Labs
    1. Multiple stool specimens (Increased yield)
       1. Fecal Leukocytes
       2. Consider Stool Culture
       3. Consider Stool Ova and Parasites (>7 days Diarrhea)
    2. Consider sending stool for antigen evaluation
       1. Giardia lamblia antigen
          1. Indicated for Diarrhea >7 days and >10 stools/day
       2. Clostridium difficile Toxin
          1. Indicated if recent antibiotics or hospitalization
       3. Rotavirus antigen
          1. Indicated for defining local outbreak
    3. Serum Electrolytes (e.g. Chem8)
       1. Hyponatremia
       2. Hypernatremia
       3. Metabolic Acidosis
       4. Hypoglycemia
12. Evaluation: Endoscopy Findings
    1. Does not distinguish Infectious from Inflammatory
    2. Sexually Transmitted Disease (STD)
       1. Lesions in Distal 15 cm in homosexual men
       2. Herpes Virus
       3. NeisseriaGonorrhea
          1. Nonspecific findings limited to rectum
          2. Biopsy and Culture show superficial exudates
       4. Syphilis
          1. Rectal Papules, Chancres, and ulcers
       5. Chlamydia (Lymphogranuloma venereum)
          1. Similar to Inflammatory Bowel Disease
13. Management: Vomiting
    1. See Vomiting
    2. See Antiemetic
    3. See Vomiting Management in Children
    4. See Vomiting in Pregnancy
14. Management
    1. See Diarrhea Management in Children
    2. Electrolyte solutions containing Glucose (not Artificial Sweetener)
       1. Glucose assists with water reabsorption
       2. Oral Rehydration Solution (ORS) is preferred but may not be tolerated well
          1. See Oral Rehydration Solution
          2. See Homemade Cereal Based ORS
          3. WHO-ORS packs
          4. Pedialyte, Rehydrate or Infalyte in children
       3. Gatorade
          1. May be used as alternative
          2. Requires 1:1 dilution with water to half strength
    3. BRAT diet plus
       1. Includes Bananas, rice, apple sauce, toast, soup, crackers
       2. Introduce as tolerated
    4. Avoid provocative agents that worsen Diarrhea
       1. Caffeine
       2. Sorbitol
       3. Lactose
15. Management: Antibiotics
    1. Use is controversial with potentially serious complications (e.g. Hemolytic Uremic Syndrome)
    2. Advantages
       1. Antibiotics appear to shorten Diarrhea course by 24 hours regardless of stool guiaic, fecal Leukocyte or Stool Culture result
    3. Disadvantages
       1. Increased Antibiotic Resistance
       2. Increased risk of prolonged carrier state with certain infections (e.g. Salmonella)
       3. Increased risk of developing Hemolytic Uremic Syndrome with E. coli 0157:H7
       4. Increased risk of Clostridium difficile
    4. Contraindications
       1. Children
       2. Elderly
       3. Patients requiring hospitalization
          1. Grossly blood stool
          2. Severe dehydration
          3. Toxic appearing patients
    5. Indications: Findings suggestive of bacterial Diarrhea
       1. Guiaic positive stool (not grossly bloody stool)
       2. Fecal Leukocyte positive
       3. Overseas travel
    6. Agents
       1. Ciprofloxacin 500 to 1000 mg once or 500 mg twice daily for 3 days or
       2. Trimethoprim-Sulfamethoxazole (Septra, Bactrim) twice daily for 3-5 days (higher resistance rates)
16. Management: Admission Criteria
    1. Severe Diarrhea with difficulty maintaining hydration
    2. Very young or very old
    3. Severe comorbid illness
    4. Severe pain
    5. High fever
    6. Intractable Vomiting
17. Prevention
    1. See Water Disinfection
    2. See Traveler's Diarrhea Prevention
    3. See Foodborne Illness Prevention
18. References
    1. Majoewsky (2012) EM:RAP-C3 2(4): 2
    2. Guerrant (2001) Clin Infect Dis 32:331-48