High-level Genetic Diversity among Invasive Streptococcus pneumoniae Isolates in Turkey.

This study aimed to obtain information about the serotypes and molecular typing characteristics of Streptococcus pneumoniae strains that cause invasive disease in Turkey. Sixty-eight S. pneumoniae isolates causing invasive pneumococcal diseases (IPDs) were collected from different regions of Turkey from 2009 to 2011. The isolates were characterized by multilocus sequence typing (MLST), pulsed-field gel electrophoresis (PFGE), and capsular serotyping. Twenty-five different serotypes were identified; serotypes 19F, 23F, 1, 14, and 7F were common and accounted for 52.9% of all serotypes. Fifty-four different PFGE profiles (pulsotypes) were observed. Twenty-three of the 68 isolates (33.8%) were clustered into nine pulsotypes. MLST analysis yielded 36 sequence types (STs), 12 of which were novel (33.3%). Comparison of the results with the global pneumococcal MLST database by eBURST analysis revealed that our strains fell into 20 different clonal complexs (CCs) and five singletons. We discovered four new alleles: two gdh, one xpt and one ddl. This study highlights the high level of diversity among pneumococcal isolates. We also identified one case of a possible capsular switching event. PMID: 26255730 [PubMed - as supplied by publisher]
Source: Japanese Journal of Infectious Diseases - Category: Infectious Diseases Authors: Tags: Jpn J Infect Dis Source Type: research