Ramos Viviana, Duarte Carolina, Díaz Aleyda, Moreno Jaime
Grupo de Microbiología, Subdirección de Investigación Científica y Tecnológica, Instituto Nacional de Salud.
Grupo de Microbiología, Subdirección de Red Nacional de Laboratorios, Instituto Nacional de Salud, Bogotá, D. C, Colombia.
Biomedica. 2014 Apr;34 Suppl 1:209-16. doi: 10.1590/S0120-41572014000500023.
Resistance to macrolide antibiotics is increasing in clinical isolates of Streptococcus pneumoniae and is associated with the presence of mobile genetic elements. Objetive: The aim of this study was to determine the distribution of serotypes and transposons among macrolide-resistant invasive isolates of S. pneumoniae in Colombia from 1994 to 2011.
A total of 225 macrolide-resistant S. pneumoniae isolates were analyzed. The isolates had epidemiological data, serotyping and antimicrobial susceptibility patterns. The phenotypes were tested by erythromycin-clindamycin double-disk test. We investigated the presence of transposons by several multiplex PCRs to identify the genes erm (B), mef(A), mef(E), tet M, Cat , Aph3 -III, int -Tn 916 , xis -Tn 916 , TnpA -Tn 917 , TnpR -Tn 917 and int -Tn 5252 .
Of all isolates, 62.7%, 2.7% and 34.6% of isolates exhibited cMLS B, iMLS B, and M phenotypes, respectively. Multiresistance was observed in 69.3% of these strains. The most prevalent genetic elements in MLS B were the Tn 5253 (34%), mostly carried in serotype 6B isolates and found to be related to the international clone Spain-ST90; Tn 1545 (18.4%), carried by serotype 19A and related to ST276, and Tn 3872 (14.9%), mainly detected in capsular types 6B and 14. Other seven transposons (32.7%) were associated with different serotypes. The mega element (62.8%) was associated to serotype 6A and ST473 in M phenotype.
The majority of erythromycin-resistance isolates of S. pneumoniae in Colombia had the cMLS B phenotype and was associated with the presence of transposons, which carry multiple resistance determinants for other antibiotics. Moreover, isolates with M phenotype carried the gene mef( E) in the mega element.
肺炎链球菌临床分离株对大环内酯类抗生素的耐药性正在增加，且与可移动遗传元件的存在有关。目的：本研究旨在确定1994年至2011年哥伦比亚肺炎链球菌大环内酯类耐药侵袭性分离株的血清型和转座子分布。
共分析了225株肺炎链球菌大环内酯类耐药分离株。这些分离株有流行病学数据、血清型和抗菌药敏模式。通过红霉素-克林霉素双碟试验检测表型。我们通过多种多重聚合酶链反应研究转座子的存在，以鉴定erm（B）、mef（A）、mef（E）、tet M、Cat、Aph3 -III、int -Tn 916、xis -Tn 916、TnpA -Tn 917、TnpR -Tn 917和int -Tn 5252基因。
在所有分离株中，分别有62.7%、2.7%和34.6%的分离株表现出cMLS B、iMLS B和M表型。在这些菌株中，69.3%观察到多重耐药。MLS B中最常见的遗传元件是Tn 5253（34%），主要存在于血清型6B分离株中，发现与国际克隆株西班牙-ST90有关；Tn 1545（18.4%），由血清型19A携带，与ST276有关，以及Tn 3872（14.9%），主要在荚膜型6B和14中检测到。其他七个转座子（32.7%）与不同血清型有关。巨型元件（62.8%）在M表型中与血清型6A和ST473有关。
哥伦比亚大多数肺炎链球菌红霉素耐药分离株具有cMLS B表型，且与转座子的存在有关，这些转座子携带其他抗生素的多种耐药决定簇。此外，具有M表型的分离株在巨型元件中携带mef（E）基因。
