Acute Psychosis as Major Clinical Presentation ofLegionnaires’ Disease

We report a case of a 61-year-old woman who presented with acute psychosis as a major manifestation of Legionnaires’ disease inthe absence of other neuropsychiatric symptoms. Clinical history revealed dry cough and nausea. Observation showed fever andauscultation crackles in the lower lobe of the right lung. Laboratory testing demonstrated elevated C-reactive protein and lung chestradiograph showed patchy peribronchial and right lower lobe consolidation. Soon after admission, she started producing purulentsputum. Epidemiological data suggestedLegionella pneumophilaas possible cause of the clinical picture that was confirmed byurinary antigen detection and polymerase chain reaction of the sputum. She was treated with levofloxacin 750 mg/day for 10 dayswith complete remission of pulmonary and psychiatric symptoms. She has not had further psychotic symptoms