[Bacillary angiomatosis of the oral cavity in AIDS. A differential diagnosis of mucosal Kaposi's sarcoma].

The diagnosis of bacillary angiomatosis (BA) was performed on a biopsy of a reddish nodular lesion of the gingival mucosa, in a patient seropositive for the H.I.V. It was based on the histopathological features, and by the demonstration of bacilli both on the Warthin-Starry stain and the electron microscopic study. A treatment by erythromycin was quickly effective. BA is an opportunistic infection seen essentially in patients with A.I.D.S., most often causing cutaneous involvement. The causative pathogen is Rochalimaea henselae. BA of the oral cavity is very rare. This infection can be mistaken with Kaposi sarcoma on its clinical appearance.