Send to

Choose Destination

See 1 citation found using an alternative search:

Am J Med. 2014 Oct;127(10):1010.e11-9. doi: 10.1016/j.amjmed.2014.03.042. Epub 2014 May 6.

Ruling out Legionella in community-acquired pneumonia.

Author information

Kantonsspital Aarau, Medical University Clinic, Aarau, Switzerland; University Clinic of Infectious Diseases, University Hospital, Inselspital Bern, Bern, Switzerland. Electronic address:
University of Basel, Basel, Switzerland.
Kantonsspital Aarau, Medical University Clinic, Aarau, Switzerland.
Division of Infectious Diseases, University of Louisville School of Medicine, Louisville, Ky.
Kantonsspital Aarau, Medical University Clinic, Aarau, Switzerland; Kantonsspital Aarau, Clinic for Infectious Diseases, Aarau, Switzerland.



Assessing the likelihood for Legionella sp. in community-acquired pneumonia is important because of differences in treatment regimens. Currently used antigen tests and culture have limited sensitivity with important time delays, making empirical broad-spectrum coverage necessary. Therefore, a score with 6 variables recently has been proposed. We sought to validate these parameters in an independent cohort.


We analyzed adult patients with community-acquired pneumonia from a large multinational database (Community Acquired Pneumonia Organization) who were treated between 2001 and 2012 with more than 4 of the 6 prespecified clinical variables available. Association and discrimination were assessed using logistic regression analysis and area under the curve (AUC).


Of 1939 included patients, the infectious cause was known in 594 (28.9%), including Streptococcus pneumoniae in 264 (13.6%) and Legionella sp. in 37 (1.9%). The proposed clinical predictors fever, cough, hyponatremia, lactate dehydrogenase, C-reactive protein, and platelet count were all associated or tended to be associated with Legionella cause. A logistic regression analysis including all these predictors showed excellent discrimination with an AUC of 0.91 (95% confidence interval, 0.87-0.94). The original dichotomized score showed good discrimination (AUC, 0.73; 95% confidence interval, 0.65-0.81) and a high negative predictive value of 99% for patients with less than 2 parameters present.


With the use of a large independent patient sample from an international database, this analysis validates previously proposed clinical variables to accurately rule out Legionella sp., which may help to optimize initial empiric therapy.


Legionella; Pneumonia; Prediction algorithm

[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center