Markovska Rumyana, Stankova Petya, Popivanov Georgi, Gergova Ivanka, Mihova Kalina, Mutafchiyski Ventsislav, Boyanova Lyudmila
Department of Medical Microbiology, Medical Faculty, Medical University of Sofia, 1431 Sofia, Bulgaria.
Department of Surgery, Military Medical Academy, 1606 Sofia, Bulgaria.
Antibiotics (Basel). 2024 Jul 21;13(7):677. doi: 10.3390/antibiotics13070677.
The rapid spread of carbapenemase-producing strains has led to increased levels of resistance among Gram-negative bacteria, especially enterobacteria. The current study aimed to collect and genetically characterize the colistin- and carbapenem-resistant isolates, obtained in one of the biggest hospitals (Military Medical Academy) in Sofia, Bulgaria. Clonal relatedness was detected by RAPD and MLST. Carbapenemases, ESBLs, and were investigated by PCR amplification and sequencing, replicon typing, and 16S rRNA methyltransferases with PCRs. Fourteen colistin- and carbapenem-resistant isolates were detected over five months. Six carbapenem-resistant and colistin-susceptible isolates were also included. The current work revealed a complete change in the spectrum of carbapenemases in Bulgaria. was the only NDM variant, and it was always combined with . The coexistence of and was observed in 10/14 (72%) of colistin- and carbapenem-resistant isolates and three colistin-susceptible isolates. All - and -positive isolates belonged to the ST6260 (ST101-like) MLST type. They showed great variability and had a higher mortality rate. In addition, we observed ST14 isolates and KPC-2-producing ST101, ST16, and ST258 isolates. The colistin- and carbapenem-resistant isolates were susceptible only to cefiderocol for - and -positive isolates and to cefiderocol and ceftazidime/avibactam for - or -positive isolates. All -positive isolates carried methylase and the colE replicon type. The extremely limited choice of appropriate treatment for patients infected with such isolates and their faster distribution highlight the need for urgent measures to control this situation.
产碳青霉烯酶菌株的迅速传播导致革兰氏阴性菌，尤其是肠杆菌科细菌的耐药水平升高。本研究旨在收集并对在保加利亚索非亚最大的医院之一（军事医学科学院）获得的耐黏菌素和耐碳青霉烯类分离株进行基因特征分析。通过随机扩增多态性DNA（RAPD）和多位点序列分型（MLST）检测克隆相关性。通过聚合酶链反应（PCR）扩增和测序、复制子分型以及PCR检测16S rRNA甲基转移酶来研究碳青霉烯酶、超广谱β-内酰胺酶（ESBLs）等。在五个月内检测到14株耐黏菌素和耐碳青霉烯类分离株。还纳入了6株耐碳青霉烯类且对黏菌素敏感的分离株。目前的研究揭示了保加利亚碳青霉烯酶谱的完全变化。新德里金属β-内酰胺酶（NDM）是唯一的NDM变体，并且它总是与其他酶结合。在10/14（72%）的耐黏菌素和耐碳青霉烯类肠杆菌科分离株以及3株对黏菌素敏感的分离株中观察到了其他酶与NDM的共存。所有同时携带其他酶和NDM的分离株属于ST6260（类似ST101）MLST型。它们表现出很大的变异性并且死亡率更高。此外，我们还观察到ST14分离株以及产KPC-2的ST101、ST16和ST258分离株。对于同时携带其他酶和NDM的阳性分离株，耐黏菌素和耐碳青霉烯类分离株仅对头孢地尔敏感；对于携带其他酶或NDM的阳性分离株，它们对头孢地尔以及头孢他啶/阿维巴坦敏感。所有携带其他酶的阳性分离株都携带armA甲基化酶和colE复制子类型。对于感染此类分离株的患者，合适治疗选择极其有限且它们传播更快，这凸显了采取紧急措施控制这种情况的必要性。
