Hot tub legionellosis.

Legionella pneumophila is the cause of Legionnaires' disease, and Pontiac fever, an influenza-like condition without pneumonia. We present a case of Pontiac fever after exposure to a hot tub contaminated with L pneumophila. A 37 y/o wf presented to the office with acute onset of sore throat, fever, headache, and myalgia. Patient was hospitalized 3 days later because of worsening shortness of air. Chest x-ray was normal. Patient was treated with 2 days of IV erythromycin and was discharged home on oral erythromycin. Her Legionella IFA was 1:16,384. Two days later, she developed chest tightness, pleuritic chest pain, and increasing shortness of air but did not have any cough or sputum production. She was re-hospitalized with a diagnosis of Pontiac fever and treated with IV erythromycin plus oral rifampin. A repeat chest x-ray remained normal. After a detailed epidemiologic history was obtained, it was noted that she became ill after using a hot tub, which her two children also used and they themselves developed a self limited illness. Water from the hot tub was positive for L pneumophila by DFA, culture, and PCR. Patient improved gradually with therapy and was discharged home. This report emphasizes the importance of a complete epidemiologic history in the diagnosis of respiratory infections. It also demonstrates that aquatic environment can be contaminated with Legionella and serve as a source of infection.