Determination of pneumococcal serotypes/genotypes in nasopharyngeal secretions of otitis media children by multiplex PCR
Determination of pneumococcal serotypes/genotypes in nasopharyngeal secretions of otitis media children by multiplex PCR
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DOI：
10.1007/s00431-007-0510-3
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发表时间：
2008-04-01
影响因子：
3.6
通讯作者：
Yamanaka, Noboru
中科院分区：
文献类型：
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作者：
Billal, Dewan S.;Hotomi, Muneki;Yamanaka, Noboru
肺炎链球菌多糖疫苗的临床应用迫切需要准确的分析方法来确定和表征血清型，以应对最近耐药性肺炎链球菌的增加。目前用抗被膜多糖特异性血清进行的血清型免疫测定的结果很难用肺炎球菌的平稳性变化来解释。在这项研究中，我们应用多重聚合酶链式反应技术快速鉴定肺炎球菌，并同时快速确定其与鼻咽分泌物(NPS)的药敏直接相关的血清型和基因型别。血清群6、19F和23F是肺炎链球菌的主要衣壳类型。19F和23F血清型菌株pbp1a、pbp2x和pbp2b突变频率高，表达ermB和mefA，对青霉素G(PCG)和克拉霉素(CAM)耐药较多。两份NPS标本中含有19F型毒株和23F型毒株，尽管常规细菌培养只鉴定出19F型毒株。用多重聚合酶链式反应检测了6份NPS标本中的肺炎球菌及其血清型，而常规细菌培养无法鉴定病原体。我们的发现表明，基于聚合酶链式反应的血清分型和基因分型可以提供准确和快速的肺炎球菌血清型和耐药性的分布。鼻咽中相对较小的种群可以用分子技术来确定。
The appropriate clinical applications of pneumococcal polysaccharide vaccines against recent increases in antimicrobial resistant Streptococcus pneumoniae (S. pneumoniae) urgently require accurate analytical methodologies for determining and characterizing the serotypes. The results of current immunological determinations of serotypes with anti-capsular polysaccharide-specific sera are difficult to interpret in terms of quellung changes of the pneumococci. In this study, we applied the multiplex PCR technique for the rapid identification of pneumococci and simultaneous rapid determinations of their serotypes and genotypes that directly correlated with antimicrobial susceptibilities from nasopharyngeal secretions (NPS). Serogroups 6, 19F and 23F were the predominant capsular types of S. pnuemoniae in the NPS samples. Strains of serotypes 19F and 23F frequently had mutations in pbp1a, pbp2x and pbp2b and expressed ermB and mefA; they also were mostly resistant to both penicillin G (PCG) and clarithromycin (CAM). Two NPS samples contained the strain of serotype 19F together with the strain of serotype 23F, although only the strain of serotype 19F was identified by a conventional bacterial culture. Pneumococci were identified in six NPS samples and their serotypes determined by the multiplex PCR, while a conventional bacterial culture failed to identify the pathogens. Our findings suggest that PCR-based serotyping and genotyping can provide an accurate and rapid distribution of pneumococcal serotypes and antimicrobial resistance. The relatively minor populations in the nasopharynx may be determined using molecular techniques.