Since 1976, when Legionella pneumophila was first characterized, more than 34 species of this gram-negative, aerobic, non—spore-forming, unencapsulated bacillus have been described. Legionella pneumophila accounts for 85% of reported cases of pneumonia caused by Legionella. Of the remaining 15%, 60% are caused by Legionella micdadei. Legionella micdadei was first discovered in 1977 at the University of Pittsburgh (Pa) as a gram-negative, weakly acid-fast bacillus isolated from the lung tissue of patients who had undergone renal transplantation and developed pneumonitis. Legionella micdadei has emerged as a significant cause of nosocomial pneumonia in immunocompromised patients. We describe a patient with systemic lupus erythematosus (SLE) who suffered from pneumonia caused by L micdadei and review the literature on this topic.
Report of a Case.
A 44-year-old white man with SLE diagnosed in 1981 experienced fevers (body temperature, 39.4°C) and headaches 1 week prior to admission to the hospital. In the past, he had