Difference between revisions of "Cholera"

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* Most people are asymptomatic, and simply have bacteria in their feces for 7-14 days
 
* Most people are asymptomatic, and simply have bacteria in their feces for 7-14 days
 
* Diarrhea is most severe in days 1-2, usually resolves in 7 days
 
* Diarrhea is most severe in days 1-2, usually resolves in 7 days
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{{Vibrio species}}
  
 
==Clinical Features==
 
==Clinical Features==

Revision as of 05:25, 15 May 2016

Background

  • Endemic to Asia, Africa, and Central and South America [1]
  • Occasionally seen on the Gulf Coast of US, due to inadequately cooked seafood.

Pathophysiology

  • Usually Vibrio cholera, which produces an enterotoxin which causes a secretory diarrhea[2]

Natural History

  • Transmission via ingestion of contaminated food or water, usually undercooked seafood
  • Incubation period between hours to 5 days, depending on size of inoculum (usually 1-2 days)[3]
  • Most people are asymptomatic, and simply have bacteria in their feces for 7-14 days
  • Diarrhea is most severe in days 1-2, usually resolves in 7 days

Vibrio species

Clinical Features

  • Classic “rice water” diarrhea with fishy odor; usually painless
  • Fluid losses can be significant, up to 1L/hr, leading to severe fluid and electrolyte depletion. However, most cases are mild.
  • Occasionally seen: sudden watery vomiting, borborygmi, abdominal cramping.

Later manifestations:

  • Fluid loss may lead to → sunken eyes, dry mouth, cold clammy skin, decreased skin turgor, or wrinkled hands and feet (also known as “washer woman’s hands”)
  • Acidosis from loss of bicarbonate
  • Muscle cramps from loss of K, Ca

Differential Diagnosis

Acute diarrhea

Infectious

Noninfectious

Watery Diarrhea

Traveler's Diarrhea

Diagnosis

Work-up

  • Fecal smears will NOT show leukocytes or erythrocytes.
  • Diagnosis can be confirmed by stool cultures on TCBS medium (must inform lab cholera is suspected so appropriate medium is used)

Evaluation

  • Diagnosis largely based on clinical presentation + epidemiological risk factors

Management

  • Aggressive volume repletion. Usually can be given orally if mild/moderate volume depletion; give rehydration solution to replete electrolyte loss. [5]
  • Oral rehydration solution includes in 1L of water: 2.6g NaCl, 2.9g Trisodium citrate, 1.5 g KCl, and 13.5 g glucose.
  • If severe dehydration, bolus with 100 ml/kg over 3 hrs. LR is solution of choice. May require more than 350 ml/kg in first 24 hours.
  • Antibiotic treatment decreases severity and duration of disease. Antibiotic resistance patterns are changing constantly. Most recommended currently is azithromycin 20mg/kg single dose.
  • Give children Zinc and Vitamin A.

Disposition

  • Admit if hypotensive or hemodynamically unstable, severe electrolyte abnormalities

See Also

References

  1. http://www.who.int/cholera/en/
  2. LaRocque R and Pietroni M. “Approach to the Adult with Acute Diarrhea in Developing Countries”. UpToDate.com
  3. Mobula LM. Community health facility preparedness for a cholera surge in Haiti. Am J Disaster Med. 2013 Autumn;8(4):235-41
  4. Marx et al. “Cholera and Gastroenteritis caused by Noncholera Vibrio Species”. Rosen’s Emergency Medicine 8th edition vol 1 pg 1245-1246.
  5. Sack DA, et al. Cholera. Lancet 2004; 363:223.
  6. Neilson AA, Mayer CA. Cholera - recommendations for prevention in travelers. Aust Fam Physician. 2010 Apr;39(4):220-6