The relationship between the phenotypic and genotypic characteristics of 105 penicillin-intermediate or -resistantStreptococcus pneumoniae isolates saved during 1994 to 1997 at the Prince of Wales Hospital and Pamela Youde Nethersole Eastern Hospital, Hong Kong, was studied. The pbp genes for penicillin-binding proteins 1a, 2b, and 2x for each isolate were amplified by PCR, and the products were digested with restriction enzymes HinfI and AluI. A combination of the pulsed-field gel electrophoresis (PFGE) profiles, pbpfingerprints, and phenotypic characteristics of capsular types and antibiograms enabled these isolates to be divided into four major groups. Seventy-four percent (78 of 105) of the strains, belonging to serotypes 23F, 19F, and 14, showed indistinguishable pbpfingerprint patterns (group A1, 1-1-1, 1-1-1), with PFGE patterns belonging to group A and its subtypes, suggesting that these strains were closely related. Eighty-three percent (65 of 78) of these isolates were also resistant to tetracycline, erythromycin, chloramphenicol, and trimethoprim. The type 23F isolates were indistinguishable from representative strains of the Spanish 23F clone by these molecular methods, indicating that these strains may be variants of the Spanish 23F clone. Serotype 6B accounted for 19% (20 of 105) of the isolates with reduced penicillin susceptibility and was made up of variants belonging to four different pbp fingerprint groups with the PFGE pattern group B, the predominant group being indistinguishable from that of the Spanish 6B clone. Other PFGE and fingerprint groups were mainly obtained from penicillin-susceptible strains of various serotypes. The results suggest that the rapid emergence of drug-resistant S. pneumoniae in Hong Kong has been due to the rapid dissemination of several successful clones.
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机译:研究了1994至1997年间在威尔斯亲王医院和香港东区尤德夫人那打素医院保存的105株青霉素中间或耐药的肺炎链球菌的表型与基因型之间的关系。通过PCR扩增每个分离株青霉素结合蛋白1a,2b和2x的 pbp em>基因,并用限制酶 Hin em> fI和消化产物。 Alu em> I。脉冲场凝胶电泳(PFGE)谱, pbp em>指纹,荚膜类型和抗菌谱的表型特征的组合使这些分离物可分为四个主要类别。属于血清型23F,19F和14的菌株中有74%(105个菌株中的78个)表现出难以区分的 pbp em>指纹图谱(A1,1-1-1,1-1-1组),PFGE模式属于A组及其亚型,表明这些菌株密切相关。这些分离株中的百分之八十三(78个中的65个)也对四环素,红霉素,氯霉素和甲氧苄啶具有抗性。通过这些分子方法,23F型分离株与西班牙23F克隆的代表性菌株没有区别,表明这些菌株可能是西班牙23F克隆的变体。血清型6B占青霉素敏感性降低的菌株中的19%(105个中的20个),由属于PFGE模式B的四个 pbp em>指纹组的变体组成,其中主要的组无法区分来自西班牙的6B克隆。其他PFGE和指纹组主要来自各种血清型的易感青霉素菌株。结果表明耐药性 S的迅速出现。肺炎 em>在香港的产生源于几个成功克隆的迅速传播。
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