Sinusitis caused by Legionella pneumophila in a patient with the acquired immune deficiency syndrome.

A patient with the acquired immune deficiency syndrome and Legionella pneumophila infection of the maxillary sinus is described. The organism was identified by direct immunofluorescence staining of sinus tissue. Because the Legionella species are intracellular pathogens, it is not surprising that this patient with a cellular immune defect was infected. However, no other site of Legionella infection was found. This appears to be the first reported case of upper respiratory tract infection by a Legionella species.