Lack of bactericidal effect of antibiotics except aminoglycosides on Bartonella (Rochalimaea) henselae

Bartonella (Rochalimaea) henselae is a cause of peliosis hepatis and bacillary angiomatosis, and one of the putative agents of cat scratch disease. Specific therapy for B. henselae infections is not available. Treatment failures and relapses are frequent, especially following brief antibiotic courses, and this contrasts with the in-vitro susceptibility of B. henselae to most antibiotics. We decided to test the antibiotic susceptibility of B. henselae associated with murine macrophage-like cells (P388 D1) and a human endothelial cell line. We carried out a bactericidal assay in this model and in axenic broth. In both models, only aminoglycosides were bactericidal. These results suggest that aminoglycosides may be effective in the treatment of B. henselae infections.