Bartonella henselae infections in solid organ transplant recipients: report of 5 cases and review of the literature.

Bartonella henselae is the causative agent of cat scratch disease and bacillary angiomatosis-peliosis. The spectrum of disease, diagnosis, and management of B. henselae infection in solid organ transplant recipients has not been well characterized. We identified 29 cases of solid organ transplant recipients who had Bartonella infection, 24 by a review of the English-language literature and 5 from our institution. Localized cat scratch disease was found in 8 patients (28%), and disseminated infection was found in 21 patients (72%). The mean time after transplantation to development of Bartonella infection among those with cat scratch disease was 5.6 ± 5.3 years, and among those with disseminated infection was 2.7 ± 2.4 years. Prominent clinical features included cat exposure in 26 patients (90%), fever in 27 patients (93%), lymphadenopathy in 12 patients (41%), and skin lesions in 7 patients (24%). Methods used in establishing the diagnosis of Bartonella infection included culture, polymerase chain reaction (PCR) assay, serologic assays, and histopathologic examination. Culture was positive in 2 of only 4 patients in whom this was performed, and PCR was positive in 12 of 14 patients (86%) in whom this test was performed. Serologic assays were positive in all 23 patients who were tested. Histopathologic examination of tissues in all 8 patients who had cat scratch disease revealed granulomatous inflammation in 4 (50%) and bacillary angiomatosis-peliosis in 2 (25%). Among the 15 patients who had disseminated infection and who had tissue examined, 8 (53%) had only granulomatous inflammation, 4 had only bacillary angiomatosis-peliosis (27%), and 2 had both granulomas and bacillary angiomatosis-peliosis (13%). A positive Warthin-Starry or Steiner stain was noted in 12 of 19 patients (63%) who had 1 of these stains performed. All 8 patients with cat scratch disease and 19 of 21 patients with disseminated bartonellosis were cured with antimicrobial therapy. Two patients, both of whom had endocarditis, died. Among solid organ transplant recipients, infection with B. henselae is uncommon and has diverse disease manifestations including disseminated disease. Persistent fevers or lymphadenopathy in a transplant recipient who has been exposed to cats should prompt clinicians to maintain a high index of suspicion for B. henselae infection. Identifying B. henselae as the causative organism often requires multiple diagnostic studies. Once the diagnosis is established, most solid organ transplant recipients respond appropriately to antimicrobial treatment.