Legionnaires' disease associated with rash and renal failure.

Legionnaires' disease is recognized as a multisystemic illness. Afflicted patients may have pulmonary, gastrointestinal tract, and central nervous system complications. However, dermal involvement is not well documented and renal insufficiency is uncommon and usually of mild severity. We report two consecutive cases of proven Legionella infection that were unusual in that a macular rash and profound renal failure requiring hemodialysis were noted. Skin biopsy specimens of the rash and autopsy findings suggest that these atypical features may have been mediated by the Legionella infection. Although it is not entirely clear from these two cases, we suggest that the skin and renal involvement may have been mediated by either a "toxin" elaborated by the organism, an immunologic response of the host to the organism, or some other unidentified mechanism.