1Institut Pasteur de Madagascar, Antananarivo, Madagascar.
Service de Pédiatrie et Néonatologie, Centre Hospitalier de Soavinandriana, Antananarivo, Madagascar.
Antimicrob Resist Infect Control. 2019 Feb 11;8:31. doi: 10.1186/s13756-019-0491-9. eCollection 2019.
The present study aimed to perform a deep phenotypic and genotypic analysis of 15 clinical carbapenem-resistant (CRAb) strains isolated in Madagascar between 2008 and 2016 from diverse sources.
CRAb isolates collected from the Clinical Biology Centre of the Institut Pasteur of Madagascar, from the neonatal unit of Antananarivo military hospital, and from intensive care units of Mahajanga Androva and Antananarivo Joseph Ravoahangy Andrianavalona (HJRA) hospitals were subjected to susceptibility testing. Whole-genome sequencing allowed us to assess the presence of antibiotic-resistance determinants, insertion sequences, integrons, genomic islands and potential virulence factors in all strains. The structure of the porin gene and deduced protein (CarO) were also CRAb isolates.
All isolates were found to be multidrug-resistant strains. Antibiotic-resistance genes against six classes of antimicrobial agents were described. The four carbapenem-resistance genes: , , , and genes were detected in 100, 53.3, 13.3, and 6.6% of the isolates, respectively. Additionally, an IS located upstream of and genes was observed in 53.3 and 66.7% of isolates, respectively. Further, Tn and Tn were found associated to the IS- structure. An 8051-bp mobilizable plasmid harbouring the gene was isolated in two strains. In addition, 46.7% of isolates were positive for class 1 integrons. Overall, five sequences types (STs), with predominantly ST2, were detected. Several virulence genes were found in the CRAb isolates, among which .
This study revealed the presence of high-level carbapenem resistance in with the first description of OXA-24 and OXA-58 carbapenemases in Madagascar. This highlights the importance of better monitoring and controlling CRAb in Madagascan hospitals to avoid their spread.
本研究旨在对 2008 年至 2016 年间从马达加斯加不同来源收集的 15 株临床碳青霉烯类耐药（CRAb）菌株进行深入的表型和基因型分析。
对来自马达加斯加巴斯德研究所临床生物学中心、塔那那利佛军事医院新生儿病房以及马任加 Androva 和塔那那利佛 Joseph Ravoahangy Andrianavalona （HJRA）医院重症监护病房的 CRAb 分离株进行药敏试验。全基因组测序用于评估所有菌株中抗生素耐药决定因素、插入序列、整合子、基因组岛和潜在毒力因子的存在情况。还分析了 15 株 CRAb 分离株的 孔蛋白基因和推导蛋白（CarO）结构。
所有分离株均为多药耐药株。描述了针对六类抗菌药物的抗生素耐药基因。在 100、53.3、13.3 和 6.6%的分离株中分别检测到 、 、 和 基因等四种碳青霉烯类耐药基因。此外，在 53.3 和 66.7%的分离株中分别观察到位于 和 基因上游的 IS。此外，Tn 和 Tn 与 IS 结构相关。从两株菌中分离到携带 基因的 8051bp 可移动质粒。此外，46.7%的分离株携带类 1 整合子。总体上检测到 5 种序列类型（ST），以 ST2 为主。在 CRAb 分离株中发现了多个毒力基因，其中包括.
本研究首次在马达加斯加发现了 OXA-24 和 OXA-58 碳青霉烯酶，表明 存在高水平的碳青霉烯耐药性。这凸显了加强对马达加斯加医院中 CRAb 的监测和控制以防止其传播的重要性。
