From Wikipedia, the free encyclopedia
| Vibrio vulnificus | |
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| False-color SEM image of Vibrio vulnificus | |
| Scientific classification | |
| Kingdom: | Bacteria |
| Phylum: | Proteobacteria |
| Class: | Gammaproteobacteria |
| Order: | Vibrionales |
| Family: | Vibrionaceae |
| Genus: | Vibrio |
| Species: | V. vulnificus |
| Binomial name | |
| Vibrio vulnificus (Reichelt et al. 1979) Farmer 1980 |
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Signs and symptoms
Vibrio vulnificus causes an infection often incurred after eating seafood, especially raw or undercooked oysters. V. vulnificus does not alter the appearance, taste, or odor of oysters.[5] The bacteria can also enter the body through open wounds when swimming or wading in infected waters,[2] or via puncture wounds from the spines of fish such as tilapia.Symptoms include vomiting, diarrhea, abdominal pain, and a blistering dermatitis that is sometimes mistaken for pemphigus or pemphigoid.
V. vulnificus is eighty times more likely to spread into the bloodstream in people with compromised immune systems, especially those with chronic liver disease. When this happens, severe symptoms including blistering skin lesions, septic shock, and even death can occur.[6][7] This severe infection may occur regardless of whether the infection began via contaminated food or via an open wound.[7]
Treatment
Vibrio vulnificus wound infections have a mortality of approximately 25%. In patients in whom the infection worsens into septicemia, typically following ingestion, the mortality rate rises dramatically to 50%. The majority of these patients die within the first 48 hours of infection. The optimal treatment is not known, but, in one retrospective study of 93 patients in Taiwan, use of a third-generation cephalosporin and a tetracycline (e.g., ceftriaxone and doxycycline, respectively) were associated with an improved outcome.[8] Prospective clinical trials are needed to confirm this finding, but in vitro data support the supposition this combination is synergistic against Vibrio vulnificus. Similarly, the American Medical Association and the Centers for Disease Control and Prevention recommend treating the patient with a quinolone or intravenous doxycycline with ceftazidime, this treatment regimen first proposed and used successfully by Dr. William Abernathy of Destin, FL. The first successful documented treatment of fulminant Vibrio vulnificus sepsis by the CDC was Patient V. B. who was diagnosed and treated by Dr. William Abernathy at Twin Cities Hospital in Niceville, FL in 1995. Treatment was Fortaz, IV Cipro, and IV doxycycline which proved successful. Secondary infections from respiratory failure and acute renal failure are key to prevent. Key to the diagnosis and treatment was early recognition of bullae in a immunocompromised patient with liver cirrhosis and oyster ingestion within the previous 48 hours, and request by the physician for STAT gram stain and blood cultures for Vibrio Vulnificus.[9]V. vulnificus often causes large, disfiguring ulcers that require extensive debridement or even amputation.
V. vulnificus is commonly found in the Gulf of Mexico, where more than dozen people have died from the infection since 1990.[10] Most deaths at that time were occurring due to fulminant sepsis either in the area of oyster harvest and ingestion, or in tourists returning home. Lack of disease recognition and the risk factors, presentation, and cause were and are major obstacles to good outcome and recovery.
After the successful treatment of patient V.B. in 1995 by Dr. William Abernathy, the CDC and the State of Florida Department of Health were able to trace back the origin of the outbreak to Appalachicola Bay oysters and their harvesting in water prone to excessive growth of the organism due to warmth of the water and lack of fresh water dilution by reduced flow of the Chatahoochee river into the Appalachicola River into the Appalachicola Bay. A similar situation occurred post Hurricane Katrina in New Orleans.
Prognosis
The worst prognosis is in those patients who arrive at hospital in a state of shock. Total mortality in treated patients (ingestion and wound) is around 33%.[8]Patients especially vulnerable are those with liver disease (especially cirrhosis and hepatitis) or immunocompromised states (cancer, bone marrow suppression, HIV, diabetes, etc.). With these cases, V. vulnificus usually enters the bloodstream where it may cause fever and chills, septic shock (with sharply decreased blood pressure), and blistering skin lesions.[11] According to the Centers for Disease Control and Prevention (CDC), about half of those who contract blood infections die.
Vibrio vulnificus infections also disproportionately affect males; 85% of those who develop endotoxic shock from the bacteria are male. Females who have had an oophorectomy experienced increased mortality rates, as estrogen has been shown experimentally to have a protective effect against V. vulnificus.[12]
History
The pathogen was first isolated in 1976 from a series of blood culture samples submitted to the CDC in Atlanta.[4] It was described as a "lactose-positive vibrio".[4] It was subsequently given the name Beneckea vulnifica,[13] and finally Vibrio vulnificus by Farmer in 1979.[14]Health officials clearly identified strains of V. vulnificus infections among evacuees from New Orleans due to the flooding there caused by Hurricane Katrina.[15]
A 59-year-old Palm Coast, Florida man died September 23, 2013, after he was exposed to the bacteria. He had been fishing for crabs in the Halifax River two days earlier. In the state of Florida, 29 cases and nine deaths have been linked to the bacteria in 2013.[16]
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