COMPARATIVE-STUDY OF THE CLINICAL PRESENTATION OF LEGIONELLA-PNEUMONIA AND OTHER COMMUNITY-ACQUIRED PNEUMONIAS

The aim of this study was to compare the clinical, biological, and rad iologic features of presentation in the emergency ward of community-ac quired pneumonia (CAP) by Legionella pneumophila (LP) and other commun ity-acquired bacterial pneumonias to help in early diagnosis of CAP by LP. Three hundred ninety-two patients with CAP were studied prospecti vely in the emergency department of a 600-bed university hospital. Uni variate and multivariate analyses were pet-formed to compare epidemiol ogic and demographic data and clinical, analytical, and radiologic fea tures of presentation in 48 patients with CAP by LP and 125 patients w ith CAP by other bacterial etiology (68 by Streptococcus pneumoniae, 4 1 by Chlamydia-pneumoniae, 5 by Mycoplasma pneumoniae, 4 by Coxiella b urnetii, 3 by Pseudomonas aeruginosa, 2 by Haemophilus influenzae, and 2 by Nocardia species. Univariate analysis showed that CAP by LP was more frequent in middle-aged, male healthy (but alcohol drinking) pati ents than CAP by other etiology. Moreover, the lack of response to pre vious beta-lactamic drugs, headache, diarrhea, severe hyponatremia, an d elevation in serum creatine kinase (CK) levels on presentation were more frequent in CAP by LP, while cough, expectoration, and thoracic p ain were more frequent in CAP by other bacterial etiology. However, mu ltivariate analysis only confirmed these differences with respect to l ack of underlying disease, diarrhea, and elevation in the CK level. We conclude that detailed analysis of features of presentation of CAP al lows suspicion of Legionnaire's disease in the emergency department. T he initiation of antibiotic treatment, including a macrolide, and the performance of rapid diagnostic techniques are mandatory in these case s.