Cholera
Cholera is a toxigenic Vibrio cholerae infection causing sudden, voluminous rice-water diarrhea from cyclic-AMP-driven intestinal secretion, diagnosed clinically and confirmed by stool culture, and treated primarily with volume-for-volume rehydration plus a single-dose antibiotic.
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What this article covers
- Overview
Toxin-mediated secretory diarrhea: cholera is an acute diarrheal illness caused by toxigenic Vibrio cholerae, a gram-negative, comma-shaped, flagellated, oxidase-positive organism that grows in…
- Epidemiology
Endemic and epidemic regions: cholera is endemic in South Asia and parts of Africa and recurs as epidemics tied to natural disasters, war, and breakdowns in water and sanitation infrastructure, with…
- Risk factors
Travel to or residence in an endemic area: South Asia, sub-Saharan Africa, and areas with recent natural disaster or displacement carry the highest exposure risk.
- Pathophysiology
Ingestion and colonization: V cholerae is ingested in contaminated water or food, survives gastric passage (more easily with reduced acid or a large inoculum), and colonizes the small intestinal mucosa without invading the epithelium.
- Clinical features
Sudden-onset watery diarrhea: the hallmark is abrupt, painless, high-volume watery diarrhea described as "rice-water" stool, gray and cloudy with flecks of mucus and no blood, without significant cramping.
- Differential diagnosis
Enterotoxigenic Escherichia coli: Escherichia coli causes a similar watery, secretory travelers' diarrhea via heat-labile and heat-stable enterotoxins, but with a longer 12- to 72-hour incubation and…
- Diagnosis
Clinical diagnosis in an outbreak setting: in a patient with sudden painless rice-water diarrhea and a compatible exposure (travel to or residence in an endemic area, contaminated water, or a…
- Management
First, classify dehydration and choose the fluid route accordingly: patients with no or mild dehydration receive oral rehydration solution alone; those with some dehydration receive oral rehydration…
- Complications
Hypovolemic shock: the dominant life-threatening complication, from stool losses that can exceed 1 L per hour; unrecognized or undertreated shock is the principal cause of death.
- Prognosis
Excellent with prompt treatment: case fatality falls to under 1% with timely, adequately dosed rehydration, reflecting how directly outcome tracks fluid replacement rather than antibiotic therapy.
- Prevention
Safe water and sanitation: boiling or chemically treating drinking water, and avoiding tap water, ice, and unpeeled raw produce in endemic areas, is the primary preventive measure for travelers and residents.
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