Vibrio parahemolyticus septicaemia in a liver transplant patient: a case report

Vibrio parahaemolyticus is a facultative anaerobic gram-negative, flagellated, halophilic, asporogenous, bacterium that inhabits marine and estuarine environments [1]. Despite its broad distribution, V. parahemolyticus infections in the United States of America are most common in individuals living in the states bordering the Gulf of Mexico [2–4]. Water temperature, salinity and turbidity correlate with increased densities of pathogenic V. parahemolyticus[2, 5]. Filter feeding animals such as shellfish, blue crabs, finfish and planktonic copepods concentrate V. parahemolyticus. Consumption of raw or undercooked seafood or exposure of wounds to warm seawater may lead to vibrio infections. The most common clinical presentation is self-limited gastroenteritis (59%), but wound infections (34%), primary septicaemia (5%) and other infection sites (2%) may also occur [3]. Persons who are immunocompromised or who have liver disease are at particularly high risk for severe vibrio infections. Necrotizing soft tissue infections are exceptional and may cause significant morbidity and mortality from invasion and destruction of fascial planes as well as the release of cytokines [6, 7].

Vibrio species are a rare cause of soft tissue infections. Exceedingly rare is soft tissue infection with V. parahemolyticus, which can occur in patients with underlying co-morbidities such as cancer, liver disease, kidney disease, heart disease, recent gastric surgery, or antacid use [4, 6]. Wound infection may occur after contamination of skin laceration with warm seawater, after direct trauma with pieces of shellfish, fishhooks or utensils contaminated with seawater or translocation from the gastrointestinal tract [6]. Bacteraemia and septicaemia occur in three to five percent of Vibrio infections and is a concern in immunocompromised patients especially those with liver disease [3]. Superficial infection can extend to deeper soft tissue causing cellulitis or necrotizing fasciitis and may require radical surgical debridement [6]. The diagnosis of V. parahemolyticus soft tissue infection is difficult. Clinical suspicion must be high in people returning from coastal areas such as the Gulf of Mexico especially with a history of raw seafood consumption or extremity wounds. Soft tissue infections are hard to recognize and difficult to differentiate from necrotizing fasciitis. Our patient underwent a bedside exploration and then debridement to definitively exclude necrotizing fasciitis. V. parahemolyticus causes skin and soft tissue necrosis which can further confound the clinical picture. Recognition of necrotizing soft-tissue infections is critical for survival because they may carry a high mortality rate. Surgical debridement must be complemented with broad spectrum antibiotic therapy. V. parahemolyticus demonstrates beta-lactamase activity in as many as 50% of isolates [8]. The vibrios are susceptible most notably to fluoroquinolones, third generation cephalosporins and doxycycline, Septicaemia and serious soft tissue infections can be treated with the synergistic combination of ceftazidime plus doxycycline or ceftazidime plus a fluoroquinolone with the latter combination being more potent in vitro[9]. There is evidence that patients with cirrhosis and end stage liver disease are susceptible to Vibrio infections [10]. This is the first case, however, in which a Vibrio parahemolyticus species infection has been reported in a liver transplant patient. It is imperative to educate patients with compromised liver function of the necessity of avoiding uncooked salt water foods and exposure to brine.

Preventing contamination of seafood is impossible since several shellfish and finfish filter and concentrate the organism. Raw seafood consumption must be discouraged, particularly for individuals at high risk for development of septicaemia, especially in people with compromised liver function or immunosuppression. Special attention should be paid to possible cross-contamination during the preparation of seafood.

Written informed consent was obtained from the patient for publication of this case report and any accompanying images. A copy of the written consent is available for review by the Editor-in-Chief of this journal.