Colon (small intestine) non tumor
Infectious colitis (enteritis)
Vibrio cholerae

Author: Elliot Weisenberg, M.D. (see Authors page)
Editorial Board Member Review: Raul Gonzalez, M.D.

Revised: 8 February 2017, last major update January 2017

Copyright: (c) 2003-2017, PathologyOutlines.com, Inc.

PubMed search: Vibrio cholerae [title] small intestine

Cite this page: Vibrio cholerae. PathologyOutlines.com website. http://www.pathologyoutlines.com/topic/colonvibrio.html. Accessed July 28th, 2017.
Definition / general
  • Infection by toxigenic strains of Vibrio cholerae O1 or V. cholerae O139
Essential features
  • Infection is caused by ingestion of toxigenic bacteria in food or water
  • Most cases are asymptomatic or cause mild diarrhea
  • Severe disease consists of a precipitous onset of acute watery diarrhea that rapidly may lead to dehydration, shock, electrolyte disturbances, renal failure and death
  • Endemic and epidemic disease can occur
  • Public health measures to prevent disease are centered on providing safe water and sanitation with vaccination in disease "hotspots" and in high risk individuals
  • Oral rehydration is the mainstay of treatment; in severe cases intravenous fluid and antibiotics are also employed
ICD-10 coding
  • A00.9
Epidemiology
  • The World Health Organization estimates that there are between 1.3 and 4.0 million cases annually with 21,000 to 143,000 deaths (WHO)
  • The Centers for Disease Control and Prevention estimates there are between 3 and 5 million cases annually with over 100,000 deaths (CDC)
  • V. cholerae has an aquatic reservoir and attaches to algae, crustacean shells or zooplankton
  • It can be metabolically active or be dormant during adverse conditions
  • The bacteria may infect seafood or be spread to human water sources causing disease; fecal-oral spread also occurs
  • V. cholerae is killed by high temperatures and tolerates acid poorly
  • In the developed world, cholera is very rare
  • Endemic disease is defined as disease that occurs during 3 of the past 5 years where there is no evidence of imported disease
    • Cholera is endemic in around 50 countries mostly in Africa, South and Southeast Asia
  • Outbreaks or epidemics are defined by the occurrence of at least 1 confirmed case with endemic local transmission where the disease is not usually encountered
    • Epidemics emerge periodically; currently an epidemic is ongoing in Haiti (CDC)
    • The Haitian epidemic is related to an encampment of Nepalese peacekeepers sent there after a catastrophic earthquake who were based at a United Nations camp; the UN has recently taken responsibility for this epidemic (UN)

  • Endemic disease:
    • Affects populations with pre-existing immunity
    • More often affects children from 2 to 15 years old
    • May be spread by ingesting food or water or the fecal-oral route
    • Has an aquatic reservoir
    • Is more likely to be asymptomatic
  • Epidemic disease:
    • Affects all ages of a nonimmune population where the bacteria does not have a reservoir
    • Spread is fecal-oral with high secondary spread
    • Asymptomatic infection is less common
  • Disease is most common in the developing world; in the developed world disease is generally encountered in travelers and immigrants
  • Rarely disease occurs from ingesting contaminated seafood, a phenomenon rarely associated with seafood from the Gulf of Mexico
  • Hypochlorhydria caused by drugs or chronic Helicobacter pylori infection is a risk factor, as is HIV infection
  • Infection is more common in summer months
  • In endemic areas, breast milk contains protective IgA antibodies
Sites
  • Small intestine
Pathophysiology
  • Symptomatology occurs due to production of an exotoxin encoded by a virulence phage that causes the small intestine to secrete fluids and electrolytes
  • V. cholerae is a noninvasive pathogen
  • The toxin has two A subunits and five B subunits
    • The two A subunits, A1 and A2, are linked by a di-sulfide bond
  • Through several steps, intracellular cyclic adenosine monophosphate opens the cystic fibrosis transmembrane regulator and chloride ions are released into the lumen while chloride and sodium ion reabsorption is inhibited by cAMP
  • There is affinity of the toxin to the ganglioside receptor on enterocytes that is higher in patients with blood type O
  • Hemagglutinin is necessary for bacterial detachment and shedding in stool
Etiology
  • Infection by toxigenic strains of Vibrio cholerae O1 or V. cholerae O139
Clinical features
  • Most cases are asymptomatic or cause mild diarrhea
  • Symptomatic cases have an incubation period of 12 hours to 5 days
  • Severe disease is characterized by sudden onset of profuse watery diarrhea often described as having a "rice water" character sometimes preceded and usually followed by vomiting
  • Patients are anxious and rapidly become dehydrated with sunken eyes, dry mucous membranes, thirst and loss of skin turgor
  • Other signs and symptoms include tachycardia, hypotension and muscle cramps
  • Untreated cases may rapidly progress to electrolyte disturbances, renal failure, shock and death
  • Rarely "cholera sicca" occurs where patients have ileus and abdominal distention but lack diarrhea; fever is uncommon
  • Children may suffer from hypoglycemia, seizures, fever and altered mental status
  • Coinfection with other pathogens may occur
Diagnosis
  • Microbiologic culture is the gold standard and may confirm other testing methods
  • PCR and real time nucleic acid sequencing are available
  • In epidemic settings, bacteria have characteristic chaotic movements when viewed by darkfield microscopy and an immunochromographic dipstick test is available
  • Testing to determine serotype and antibiotic sensitivity is necessary
  • In the United States, all cell isolates should be sent to the CDC via state health departments
Prognostic factors
  • Elderly and debilitated patients have a worse prognosis
  • Pregnant patients do worse and have a high rate of fetal loss
  • HIV infection confers an increased risk of acquiring disease
  • Subjects with blood group O are at lower risk of acquiring disease, but it is worse when it occurs
Case reports
Treatment
  • Most patients are successfully treated with oral rehydration solution (ORS); treatment should begin promptly
  • Patients with moderate to severe disease or who cannot tolerate ORS should receive intravenous hydration
  • With severe disease, antibiotic treatment is indicated to reduce fluid requirements and disease duration
  • Quinolones, trimethoprim-sulfamethoxazole, tetracycline, doxycycline, erythromycin and azithromycin have been used; antibiotic resistance is common and antimicrobial sensitivity should guide treatment
  • Three oral vaccines are effective; vaccinations should be given to populations in disease "hotspots" and travellers at high risk of acquiring disease
  • Zinc supplementation reduces disease severity in children in resource limited areas
Clinical images
Images hosted on other servers:

Child with cholera

Adult with severe dehydration due to cholera

Gross description
  • Gross changes are rarely encountered
Microscopic (histologic) description
  • Biopsy is rarely performed
  • Mucosa is normal or may show a mild neutrophilic infiltrate of the lamina propria
Videos


Small intestine - Cholera & Vibrio cholerae
Differential diagnosis
  • Clinically mild to moderate disease mimics many types of gastroenteritis, but the precipitous onset of profuse watery diarrhea is very characteristic of severe cholera
Board review question #1
  • Which statement regarding Vibrio cholerae infection is correct?
  • A. Severe disease is due to bloody diarrhea resembling inflammatory bowel disease
  • B. Most cases are asymptomatic or cause mild diarrhea
  • C. Antibiotics are the initial treatment in most cases
  • D. Infection is primarily caused by exposure to household contacts
Board review answer #1
B is correct. Most cases are asymptomatic or cause mild diarrhea

A is incorrect. Severe disease consists of a precipitous onset of acute watery diarrhea that rapidly may lead to dehydration, shock, electrolyte disturbances, renal failure and death.
C is incorrect. Oral rehydration is the mainstay of treatment; in severe cases intravenous fluid and antibiotics are also employed.
D is incorrect. Infection is caused by ingestion of toxigenic bacteria in food or water.