Streptococcus pyogenes Pneumonia in Adults: Clinical Presentation and Molecular Characterization of Isolates 2006-2015.

• Main Authors: Esther Tamayo, Milagrosa Montes, Diego Vicente, Emilio Pérez-Trallero
• Format: Article
• Language: English
• Published: Public Library of Science (PLoS) 2016-01-01
• Series: PLoS ONE
• Online Access: http://europepmc.org/articles/PMC4814053?pdf=render

INTRODUCTION:In the preantibiotic era Streptococcus pyogenes was a common cause of severe pneumonia but currently, except for postinfluenza complications, it is not considered a common cause of community-acquired pneumonia in adults. AIM AND MATERIAL AND METHODS:This study aimed to identify current clinical episodes of S. pyogenes pneumonia, its relationship with influenza virus circulation and the genotypes of the involved isolates during a decade in a Southern European region (Gipuzkoa, northern Spain). Molecular analysis of isolates included emm, multilocus-sequence typing, and superantigen profile determination. RESULTS:Forty episodes were detected (annual incidence 1.1 x 100,000 inhabitants, range 0.29-2.29). Thirty-seven episodes were community-acquired, 21 involved an invasive infection and 10 developed STSS. The associated mortality rate was 20%, with half of the patients dying within 24 hours after admission. Influenza coinfection was confirmed in four patients and suspected in another. The 52.5% of episodes occurred outside the influenza seasonal epidemic. The 67.5% of affected persons were elderly individuals and adults with severe comorbidities, although 13 patients had no comorbidities, 2 of them had a fatal outcome. Eleven clones were identified, the most prevalent being emm1/ST28 (43.6%) causing the most severe cases. CONCLUSIONS:S. pyogenes pneumonia had a continuous presence frequently unrelated to influenza infection, being rapidly fatal even in previously healthy individuals.