Incidence of a novel infectious agent in patients with advanced cardiovascular disease awaiting heart transplantation

Background: Bartonella henselae is a novel bacterial intracellular pathogen causing a self-limited syndrome of fever and regional lymphadenopathy in human immunocompetent hosts. This infection is often under-detected but it is of increased interest for a plethora of subjects including those suffering Cardiovascular Disease (CVD). Moreover, in a particular population, B. henselae can promote a severe disseminated disease with a pathologic vasoproliferation known as bacillary angiomatosis or bacillary peliosis. The role of the host immune response to B. henselae is critical in preventing progression to a major systemic disease causing an extended hepatic and CVD damage. Aim: The spectrum of disease, diagnosis and management of B. henselae infection in solid organ transplant recipients has not been investigated in depth. Until now, only rare cases of bartonellosis in transplant recipients have been reported. The purpose of this study was to evaluate the seroprevalence of B. henselae in patients awaiting heart transplantation in our Regional Reference Transplantation Centre. Methods: The diagnosis of B. henselae is usually based on serological methods (IgM, IgG) since they are practical, simple and rapid. Serum samples from 21 (16M, 5F) patients awaiting heart transplantation, with a median age of 53+/-15SD (range8–68 years), were examined by indirect immunofluorescence assay. Results: In our study, we have found a B. henselae antibody positivity rate of 19.04% (4/21) and, in particular, 1/21 (4.76%) patients presented IgM while 3/21 (14.28%) presented IgG. Our serological data seems to support the concept that B. henselae not only is present in our area and, more interestingly, it can be present in a paricular class of CVD patients represented by those awaiting heart transplantation. Conclusions: Thus, on the basis of our data, we would recommend the relevance of including B. henselae in the multipanel diagnosis in CVD patients awaiting heart transplantation.