Cholera differential diagnosis


 * Associate Editors-In-Chief: Priyamvada Singh, MBBS [mailto:psingh@perfuse.org]

Overview
Patients with cholera may give a history of consumption of contaminated food or water, and travel to an endemic area. The symptoms usually develop within 24-48 hour of consumption of contaminated food. Patient presents with sudden onset, painless, odorless, rice watery large volume stool, abdominal cramps, vomiting and fever. It should be differentiated from other infectious causes of diarrhea for e.g. rotavirus, E.coli, amebic dysentry and giardiasis. It should also be differentiated from some non-infectious causes of diarrhea for e.g. VIPoma, tubulovillous adenoma and food poisoning.

Infectious Diarrhea

 * It may be difficult to differentiate cholera from other infectious causes of diarrhea specially if it is mild and in early stages.
 * Fresh stool microscopy, stool culture, PCR and other techniques help to differentiate these conditions. Stool tests are useful, cheap and frequently used test to differentiate cholera from other infectious conditions. Other tests like PCR, serotyping though sensitive and specific, may not be performed because of the cost or non-availability at many centers.

Shigella

 * Shigella has acute bloody diarrhea whereas cholera has watery diarrhea
 * Shigella causes invasive diarrhea thus presents with symptoms of fever, abdominal cramp and rectal pain. These symptoms are lacking in cholera.
 * Vomiting is usually absent in Shigella but is frequently seen in cholera.

Amoebic, hemorrhagic E.coli dysentery

 * Bloody diarrhea is not found in cholera and guides to a diagnosis of dysentery
 * The volume of stool is not as high as seen with Cholera.

Giardiasis

 * The volume of stool is not as high as seen with Cholera.
 * Stool microscopy is used to detect eggs and parasite.
 * Stool in giardiasis produce strong odour whereas cholera usually has odourless stools.

Strongyloides

 * The volume of stool is not as high as seen with Cholera.
 * Stool microscopy is used to detect eggs and parasite.

Food poisoning

 * The volume of stool is not as high as seen with Cholera.

VIPoma

 * Chronic history of diarrhea
 * Volume of stool is not as high as seen with Cholera.
 * Negative stool examination and culture.
 * Fasting gut hormones are confirmatory for the diagnosis.

Tubulovillous adenoma
(By organ system)
 * Colonoscopy and biopsy are confirmatory for the diagnosis.
 * Chronic history of diarrhea
 * Volume of stool is not as high as seen with Cholera.
 * Negative stool examination and culture.