Clinical Information

Legionnaires' disease is caused by Legionella pneumophila and is characterized as an acute febrile respiratory illness ranging in severity from mild illness to fatal pneumonia. The mortality rate, ranging from 25%-40%, can be lowered if the disease is diagnosed rapidly and appropriate antimicrobial therapy is instituted early. Known risk factors for contracting Legionella pneumophila include immunosuppression, cigarette smoking, alcohol consumption and concomitant pulmonary disease. Contaminated, aerosolized water systems are a major source of disease. The young and elderly are particularly susceptible. Legionella pneumophila is responsible for 80%-90% of reported cases of Legionella infection with serogroup 1 accounting for greater than 70% of all legionellosis. Current methods for laboratory detection of pneumonia caused by Legionella pneumophila require a respiratory specimen (sputum, bronchial washing, etc.). Unfortunately, one of the presenting signs of patients with Legionaries' disease is the relative lack of productive sputum. The BinaxNOW Legionella Urinary Antigen Test allow for early diagnosis of Legionella pneumophila serogroup 1 infection through the detection of a specific soluble antigen present in the urine of infected patients. Legionella pneumophila serogroup 1 antigen has been detected in urine as early as three days after the onset of symptoms and persists for up to one year.