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Noncholera Vibrio Infections


Larry M. Bush

, MD, FACP, Charles E. Schmidt College of Medicine, Florida Atlantic University;

Maria T. Vazquez-Pertejo

, MD, FACP, Wellington Regional Medical Center

Reviewed/Revised Apr 2022 | Modified Sep 2022

Noncholera vibrios include the gram-negative bacteria Vibrio parahaemolyticus, V. mimicus, V. alginolyticus, V. hollisae, and V. vulnificus; they may cause diarrhea, wound infection, or septicemia. Diagnosis is by culture. Treatment is with ciprofloxacin or doxycycline.

Noncholera vibrios are sometimes called nonagglutinable vibrios (ie, they do not agglutinate with serum from cholera patients). They typically inhabit warm salt water or mixed salt and fresh water (eg, in estuaries).

V. parahaemolyticus, V. mimicus, and V. hollisae usually cause food-borne outbreaks of diarrhea, typically involving inadequately cooked seafood (usually shellfish).

V. parahaemolyticus infections typically occur in Japan and in coastal areas of the US. The organisms damage intestinal mucosa but do not produce enterotoxin or invade the bloodstream. Also, wound infection may develop when contaminated warm seawater enters a minor wound.

V. alginolyticus and V. vulnificus can cause serious wound infection; neither causes enteritis. V. vulnificus, when ingested by a compromised host (often someone with chronic liver disease or immunodeficiency), can cross the intestinal mucosa without causing enteritis and cause septicemia with a high case fatality rate; occasionally, otherwise healthy people develop such infections.

Symptoms and Signs of Noncholera Vibrio Infections

Enteric illness begins suddenly after a 15- to 24-hour incubation period; manifestations include cramping abdominal pain, large amounts of watery diarrhea (stools may be bloody and contain polymorphonuclear leukocytes), tenesmus, weakness, and sometimes nausea, vomiting, and low-grade fever. Symptoms subside spontaneously in 24 to 48 hours.

Diagnosis of Noncholera Vibrio Infections

  • Cultures

Noncholera Vibrio wound and bloodstream infections are readily diagnosed with routine cultures. When enteric infection is suspected, Vibrio organisms can be cultured from stool on thiosulfate citrate bile salts sucrose medium. Contaminated seafood also yields positive cultures.

Treatment of Noncholera Vibrio Infections

  • Ciprofloxacin or doxycycline for enteric infection

  • Antibiotics and often debridement for wound infection

Noncholera Vibrio enteric infections can be treated with a single oral dose of one of the following:

  • Ciprofloxacin 1 g

  • Doxycycline 300 mg

However, generally, such treatment is not necessary because the infection is self-limited, although treatment may be considered in severe cases.

If diarrhea is present, close attention to volume repletion and replacement of lost electrolytes are needed.

For wound infections, antibiotics are used—typically, oral doxycycline 100 mg every 12 hours, with or without a 3rd-generation cephalosporin for severe wound infection or septicemia. Ciprofloxacin is an acceptable alternative.

Patients with necrotizing fasciitis require surgical debridement.

Key Points

  • Noncholera vibrios may cause diarrhea, wound infection, or septicemia, depending on the species and mode of exposure.

  • Diagnose using cultures of stool, wound, or blood as appropriate.

  • Treat severe enteric infections with a single dose of ciprofloxacin or doxycycline.

  • Treat wound infections with doxycycline; for severe infection, add a 3rd-generation cephalosporin.

  • Necrotizing fasciitis requires surgical debridement.

Drugs Mentioned In This Article

Drug Name Select Trade
Cetraxal , Ciloxan, Cipro, Cipro XR, OTIPRIO, Proquin XR
Acticlate, Adoxa, Adoxa Pak, Avidoxy, Doryx, Doxal, Doxy 100, LYMEPAK, Mondoxyne NL, Monodox, Morgidox 1x, Morgidox 2x , Okebo, Oracea, Oraxyl, Periostat, TARGADOX, Vibramycin, Vibra-Tabs
NOTE: This is the Professional Version. CONSUMERS: View Consumer Version
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