Bacillary angiomatosis (BA) is a rare infectious disease usually associated with HIV infection. Recent molecular biologic investigations confirm that both Rochalimaea henselae and Rochalimaea quintana can cause BA. The bacteria can be identified by Warthin-Starry staining and electron microscopy. The typical clinical signs are solitary or multiple dermal or subcutaneous nodules. Bone, liver, spleen and other organs may also be involved. We describe the clinical and histological features of a 39-year-old HIV-infected patient with cutaneous and bony lesions of BA. All manifestations of BA disappeared during therapy with erythromycin.