Bacillary angiomatosis and bacillary splenitis in immunocompetent adults

Bacillary angiomatosis and bacillary peliosis have been described in patients with human immunodeficiency virus (HIV) infection and drug-induced immunosuppression. Patients with these vascular lesions in the absence of profound immunodeficiency have not been well characterized. We studied five patients with histologically confirmed bacillary angiomatosis or bacillary splenitis without clinical immunodeficiency. Studies to detect HIV infection, immunologic defects, and presence of Rochalimaea species DNA in infected tissues were done. Cell cultures were negative for HIV-1 replication, and HIV-1 DNA was not detected. Results of lymphocyte subsets and activation, neutrophil oxidative burst, skin testing to mumps antigen, and assays for quantitative immunoglobulins and complement were normal. DNA amplification and sequencing confirmed infection by Rochalimaea henselae, even in tissue showing bacillary splenitis without peliosis. Bacillary angiomatosis and bacillary splenitis may occur in the absence of demonstrable immunodeficiency. On the basis of the therapeutic response of these five patients, we recommend treatment with erythromycin or doxycycline for a minimum of 6 weeks.