Clinical predictors for Legionella in patients presenting with community-acquired pneumonia to the emergency department.

Background: Legionella species cause severe forms of pneumonia with high mortality and complication rates. Accurate clinical predictors to assess the likelihood of Legionella community-acquired pneumonia (CAP) in patients presenting to the emergency department are lacking.

Methods: We retrospectively compared clinical and laboratory data of 82 consecutive patients with Legionella CAP with 368 consecutive patients with non-Legionella CAP included in two studies at the same institution.

Prognostic value of procalcitonin in Legionella pneumonia.

The diagnostic reliability and prognostic implications of procalcitonin (PCT) (ng/ml) on admission in patients with community-acquired pneumonia (CAP) due to Legionella pneumophila are unknown. We retrospectively analysed PCT values in 29 patients with microbiologically proven Legionella-CAP admitted to the University Hospital Basel, Switzerland, between 2002 and 2007 and compared them to other markers of infection, namely, C-reactive protein (CRP) (mg/l) and leukocyte count (10(9)/l), and two prognostic severity assessment scores (PSI and CURB65). Laboratory analysis demonstrated that PCT values on admission were >0.