A patient with AIDS developed subcutaneous nodules and associated osteolytic lesions with negative stains and cultures for bacteria, fungi and parasites. Flucloxacillin was not effective but treatment with vancomycin was associated with improvement. Six months later the patient became severely ill, with fever, malaise and multiple skin and laryngeal papules. Cat-scratch disease was diagnosed from the typical epithelioid angiomatosis seen in skin biopsies with bacterium-like structures in the Warthin-Starry stain. Retrospectively these typical structures were also seen in earlier biopsies. All lesions improved after therapy with erythromycin had been instituted.