Acute diarrhea

Background

• 85% of diarrhea is infectious in etiology
• Definitions
  • Diarrhea: Increased frequency of defection, usually >3 bowel movements per day
  • Hyperacute: 1-6 hr
  • Acute: less than 3 wks in duration
  • Gastroenteritis: Diarrhea with nausea and/or vomiting
  • Dysentery: Diarrhea with blood/mucus/pus
  • Invasive = Infectious

Diagnosis

DDX Emergent

1. Appendicitis
2. Mesenteric ischemia
3. Ectopic
4. CO poisoning
5. SAH
6. Diverticultis

History

1. Possible food poisoning?
2. Does it resolve (osmotic) or persist (secretory) w/ fasting?
3. Are the stools of smaller volume (large intestine) or larger volume (small intestine)
4. Fever or abdominal pain? (diverticulitis, gastroenteritis, IBD)
5. Bloody or melenic?
6. Tenesmus? (shigella)
7. Malodorous? (giardia)
8. Recent travel?
9. Recent Abx?
10. HIV/immunocomp/sexual hx
11. Heat intolerance and anxiety? (thyrotoxicosis)
12. Paresthesias or reverse temperature sensation? (ciguatera)

Physical Exam

1. Thyroid masses
2. Oral ulcers, erythema nodosum, episcleritis, anal fissure (IBD)
3. Reactive arthritis (Arthritis, conjunctivitis, urethritis)
   1. Suggests infx w/ salmonella, shigella, campylobacter, or yersinia
4. Rectal exam for fecal impaction
5. Guaiac
6. Abdominal pain out of proportion to exam (mesenteric ischemia)

Work-Up

Only indicated for:

• • Diarrhea a/w severe abdominal pain and fever
  • Symptoms >3d
  • Blood or pus in stool
  • Immunocompromised pts
  • Systemic illness

1. Fecal leukocytes
   1. Used to differentiate invasive from noninvasive infectious diarrheas
   2. Sn 50-80%, Sp 83% for presence of bacterial pathogen
   3. If pt has +leukocytes but negative infection consider IBD
2. Stool culture
   1. Plays minor role in ED evaluation
   2. Yield is only 1.5-5.5%
3. O&P
   1. Indicated if parasitic cause is suspected
      1. Untreated water, diarrhea >7d
4. C. diff toxin
   1. 10% false negative rate
   2. Takes 24hr to run
5. Chemistry
   1. Warranted in severely ddhydrated pts
6. Abd x-ray
   1. Consider if h/o abdominal sx (r/o obstruction)
7. CXR
   1. Consider if diarrhea + cough (Legionella)
8. CT
   1. Consider if suspect mesenteric ischemia

Treatment

1. Oral rehydration
2. Food avoidance:
   1. Caffeine (incr gastric motility), raw fruits (increases osmotic diarrhea), lactose

Toxigenic v. Infectious

Characteristic	Toxic	Infectious/Invasive
Incubation	2-12h	1-3d
Onset	abrupt	gradual
Duration	<10-24h	1-7days
Fever	No	Yes
Abdominal Pain	Minimal	Yes, tenesmus
Systemic	No	Yes, myalgias, N/V
Physical findings	Nontoxic	Toxic
Abdominal Tenderness	No	Yes
Stool Blood, WBCs	No	Yes

Work Up

1. Toxigenic:Nothing
2. Invasive:
   1. Stool Cx
      1. Additional Cx: E.Coli 0157:H7
3. C. dif toxin
4. Sool O&P
   1. 1. only if suspect parasitic, recent travel, failed abx, chronic diarrhea, immunocompromised
5. Send stool WBCs only if diagnosis is uncertain; Sensitivity: 60-85% (ie unclear if invasive or toxigenic)

Treatment

Toxigenic

1. Rehydrate with fluids containing sugar, salt, fluids po, IV NS
2. Avoid high osmolality (gatorade!), caffeine, lactose-containing (lactase removed during infection)
3. Eat! - BRAT diet (small amounts banana, rice, apple sauce, toast) - will speed up recovery
4. Analgesia as needed
5. Anti-diarrheals
6. Kaolin-pectin agents
7. Bismuth
8. Antimotility (avoid alone in invasive illness)

Infectious

Above plus:

1. Antibiotics
   1. Ciprofloxacin 500mg po bid or
   2. Levofloxacin 500mg po qd or
   3. Bactrim DS 1tab po bid (+/-)
2. 3-7d treatment

Empiric Abx

1. Toxic appearance
2. Vital abnl
3. Fever >39
4. Bloody diarrhea
5. Severe dehydration

Loperimide Contraindications

1. Pediatric
2. IBD
3. C. Diff
4. Dysentery

(always give with abx)

WHO Oral Rehydration

1. 1 cup orange juice
2. 4 tsp sugar
3. 1 tsp baking powder
4. 3/4 tsp salt
5. in 1 liter of H2O

Other

Octreotide can be used in AIDS-associated diarrhea unresponsive to loperimide

Consider Pepto-Bismol for traveler's diarrhea (contraindicated in HIV-->encephalopathy)

Source

3/12/06 DONALDSON (adapted from Rosen); 09 Birnbaumer