[Community acquired pneumonia. Report of 8 cases of severe pneumonia by serogroup 1 Legionella pneumophila in Chile].

Legionella pneumophila is the second cause of severe community acquired pneumonia. In Chile, however, there are few reports of pneumonia caused by Legionella. We report eight patients (6 men, aged 42 to 72 years old) with community-acquired pneumonia caused by Legionella pneumophila serogroup 1, confirmed by the measurement of urinary antigen. Clinical presentation was characterized by fever or hypothermia (in one case), cough, dyspnea and neurological abnormalities in four patients. Cigarette smoking was the most frequently identified risk factor. All patients had at least one American Thoracic Society severity criteria. Complications observed were acute hypoxemic respiratory failure in seven patients, shock in four, renal failure in four and need for mechanical ventilation in three. No patient died.