Vibrio vulnificus infection in a hemodialysis patient receiving intravenous iron therapy

Vibrio vulnificus Septicemia After Handling Tilapia Species Fish: A Canadian Case Report and Review

BACKGROUND

Vibrio vulnificus can cause a necrotizing soft tissue infection or primary septicemia; these infections are collectively known as vibriosis. This bacterium is commonly found within molluscan shellfish. Primary septicemia is often fatal, principally affecting persons with chronic liver disease.

CASE PRESENTATION

A fatal case of V vulnificus sepsis that developed in a patient with chronic hepatitis B and chronic renal failure is reported. Diagnosis was made by isolation of the pathogen by blood culture. Upon further questioning, the patient's family recounted that the patient had handled and ingested Tilapia species fish in the hours preceding the patient's presentation. Despite treatment with doxycycline and cefotaxime, in conjunction with supportive care in the intensive care unit, the patient died on day 7 from multiple organ dysfunction.

CONCLUSION

The present case highlights the need to consider V vulnificus in the microbiological differential diagnosis when a person presents with sepsis and bullous cutaneous lesions. The importance of educating patients with liver disease (and certain other chronic diseases) about the need to be cautious when handling or consuming seafood is underscored.

A comprehensive review of Vibrio vulnificus: an important cause of severe sepsis and skin and soft-tissue infection

Vibrio vulnificus is a halophilic Gram-negative bacillus found worldwide in warm coastal waters. The pathogen has the ability to cause primary sepsis in certain high-risk populations, including patients with chronic liver disease, immunodeficiency, iron storage disorders, end-stage renal disease, and diabetes mellitus. Most reported cases of primary sepsis in the USA are associated with the ingestion of raw or undercooked oysters harvested from the Gulf Coast. The mortality rate for patients with severe sepsis is high, exceeding 50% in most reported series. Other clinical presentations include wound infection and gastroenteritis. Mild to moderate wound infection and gastroenteritis may occur in patients without obvious risk factors. Severe wound infection is often characterized by necrotizing skin and soft-tissue infection, including fasciitis and gangrene. V. vulnificus possesses several virulence factors, including the ability to evade destruction by stomach acid, capsular polysaccharide, lipopolysaccharide, cytotoxins, pili, and flagellum. The preferred antimicrobial therapy is doxycycline in combination with ceftazidime and surgery for necrotizing soft-tissue infection.

Hemochromatosis and Vibrio vulnificus wound infections

There are several reports of persons with hemochromatosis and Vibrio vulnificus primary septicemia, but few accounts of persons with hemochromatosis and V. vulnificus wound infection. A 58-year-old white man developed infection of a forearm injury exposed to seawater in the Gulf of Mexico near the Alabama coast. At age 66, he was diagnosed to have hemochromatosis. Transferrin saturation was 89% and serum ferritin was 4761 pmol/L. HFE genotype was C282Y/C282Y. Serum levels of hepatic enzymes, glucose, IgG, IgA, and IgM, and blood levels of T, B, and natural killer cells were normal. We identified previous reports of only 2 similar cases: a woman from Alabama and a man from northern Australia. Mean age of the 3 subjects was 51 years at diagnosis of infection. Each had elevated serum iron measures or iron overload complications; both men were diagnosed to have hemochromatosis after they developed infection. Each of the 3 had recent exposure of a wound on an extremity to seawater, rapid development of a necrotizing soft tissue infection that required debridement and skin grafting, and positive wound or blood cultures. Each subject survived the infection. V. vulnificus wound infection occurs in some persons with hemochromatosis, but the risk of infection may be small. All patients with V. vulnificus infections should be evaluated for hemochromatosis, iron overload, and liver disorders.

Vibrio vulnificus Bacteremia Associated with Chronic Lymphocytic Leukemia, Hypogammaglobulinemia, and Hepatic Cirrhosis: Relation to Host and Exposure Factors in 252 V. Vulnificus Infections Reported in Louisiana

BACKGROUND

Vibrio vulnificus infection in persons with B-chronic lymphocytic leukemia (B-CLL) or hypogammaglobulinemia has been reported infrequently.

PATIENT AND METHODS

A woman with B-CLL, hypogammaglobulinemia, and hepatic cirrhosis died of V. vulnificus bacteremia after eating cooked shrimp and crabs. We reviewed host and exposure data in 252 cases of V. vulnificus infection reported in Louisiana during the interval of 1980 through 2004.

RESULTS

V. vulnificus was isolated from blood in 122 cases (48.8%). Preexisting conditions in 138 cases included liver disease (41.3%), malignancy (13.8%), and immunosuppression (9.4%). The prevalence of preexisting conditions was significantly greater in cases with positive blood cultures than in cases with positive wound or stool cultures. Exposure data in 116 cases revealed crab consumption without raw oyster consumption or seawater exposure in 3.4%.

CONCLUSION

The present patient had several conditions associated with increased risk of V. vulnificus infection and bacteremia, especially hepatic cirrhosis, but her route of exposure to V. vulnificus was unusual.

Rapidly progressive soft tissue infections

Skin and soft tissue infections are among the most common reasons for people to seek medical advice. They also represent one of the most common indications for antimicrobial therapy and account for approximately 7-10% of hospitalisations in North America. Although non-limb and non-life threatening infections may be treated on an out-patient basis with oral antibiotics, patients with more serious acute skin and soft tissue infections may require admission to hospital for management; this decision is especially true if the infection is rapidly progressive. We provide a concise overview of the differential diagnosis and approach to management of community-acquired rapidly progressive skin and soft tissue infections.

Hybrid Vibrio vulnificus

Hybridization between natural populations of Vibrio vulnificus results in hyperinvasive clone.

The recent emergence of the human-pathogenic Vibrio vulnificus in Israel was investigated by using multilocus genotype data and modern molecular evolutionary analysis tools. We show that this pathogen is a hybrid organism that evolved by the hybridization of the genomes from 2 distinct and independent populations. These findings provide clear evidence of how hybridization between 2 existing and nonpathogenic forms has apparently led to the emergence of an epidemic infectious disease caused by this pathogenic variant. This novel observation shows yet another way in which epidemic organisms arise.

Rust and corrosion in hematopoietic stem cell transplantation: the problem of iron and oxidative stress

Iron overload is a common acute and long-term event associated with autologous and allogeneic hematopoietic stem cell transplantation (HSCT). In a state of iron excess, free iron becomes available to catalyze the conversion of reactive oxygen species (ROS) intermediates such as superoxide anion (O2*-) and hydrogen peroxide (H2O2) to highly toxic free radicals such as hydroxyl radical (OH*). ROS may help to promote chronic liver disease, sinusoidal obstruction syndrome, idiopathic pneumonia syndrome and bacterial, fungal and other opportunistic infections. Phlebotomy has been effectively and safely used to deplete excess iron stores post-HSCT in thalassemic and other iron-overloaded patients. Intracellular iron levels may also be decreased through pharmacologic chelating agents, while antioxidants such as N-acetylcysteine, glutamine (glutathione precursor) and captopril have been shown to replenish glutathione redox potential and scavenge free radicals. A better understanding of the mechanisms involved in the iron-generated pro-oxidant state associated with HSCT will likely lead to reduced toxicity and improved patient outcomes.