El-Mokhtar Mohamed A, Daef Enas, Mohamed Hussein Aliae A R, Hashem Maiada K, Hassan Hebatallah M
Department of Medical Microbiology and Immunology, Faculty of Medicine, Assiut University, Assiut 71515, Egypt.
Microbiology and Immunology Department, Faculty of Pharmacy, Sphinx University, Assiut 71515, Egypt.
Antibiotics (Basel). 2021 Feb 24;10(3):226. doi: 10.3390/antibiotics10030226.
(1) Background: Colistin is a last-resort antibiotic used in treating multidrug-resistant Gram-negative infections. The growing emergence of colistin resistance in represents a serious health threat, particularly to intensive care unit (ICU) patients. (2) Methods: In this work, we investigated the emergence of colistin resistance in 140 nosocomial isolated from patients with pneumonia and admitted to the chest ICU over 36 months. Virulence and resistance-related genes and pathotypes in colistin-resistant and colistin-sensitive isolates were determined. (3) Results: Colistin resistance was observed in 21/140 (15%) of the nosocomial isolates. The MIC of the resistant strains was 4 mg/L, while MIC was 16 mg/L. Colistin-resistant isolates were also co-resistant to amoxicillin, amoxicillin/clavulanic, aztreonam, ciprofloxacin, and chloramphenicol. The mechanism of colistin resistance was represented by the presence of in all resistant strains. Respectively, 42.9% and 36.1% of colistin-resistant and colistin-sensitive groups were extended-spectrum β-lactamase (ESBL) producers, while 23.8% and 21% were metallo β-lactamase (MBL) producers. was the most frequently detected ESBL gene, while was the most common MBL in both groups. Importantly, most resistant strains showed a significantly high prevalence of (76.2%), (76.2%), and (52.4%) virulence-related genes. Enteroaggregative (76%) was the most frequently detected genotype among the colistin-resistant strains. (4) Conclusion: The high colistin resistance rate observed in strains isolated from patients with nosocomial pneumonia in our university hospital is worrisome. These isolates carry different drug resistance and virulence-related genes. Our results indicate the need for careful monitoring of colistin resistance in our university hospital. Furthermore, infection control policies restricting the unnecessary use of extended-spectrum cephalosporins and carbapenems are necessary.
(1) 背景：黏菌素是治疗多重耐药革兰氏阴性菌感染的一种最后手段的抗生素。黏菌素耐药性的日益出现对健康构成严重威胁，尤其是对重症监护病房（ICU）的患者。(2) 方法：在这项研究中，我们调查了36个月内从肺炎患者中分离并入住胸科ICU的140株医院分离株中黏菌素耐药性的出现情况。测定了黏菌素耐药和敏感分离株中与毒力和耐药相关的基因以及致病型。(3) 结果：在140株医院分离株中有21株（15%）出现黏菌素耐药。耐药菌株的最低抑菌浓度（MIC）为4mg/L，而敏感菌株的MIC为16mg/L。黏菌素耐药分离株还对阿莫西林、阿莫西林/克拉维酸、氨曲南、环丙沙星和氯霉素耐药。所有耐药菌株中均存在[具体基因名称未给出]，这代表了黏菌素耐药的机制。黏菌素耐药组和敏感组分别有42.9%和36.1%的菌株产超广谱β-内酰胺酶（ESBL），而产金属β-内酰胺酶（MBL）的菌株分别为23.8%和21%。[具体ESBL基因名称未给出]是最常检测到的ESBL基因，而[具体MBL基因名称未给出]是两组中最常见的MBL。重要的是，大多数耐药菌株显示[具体毒力相关基因名称未给出]（76.2%）、[具体毒力相关基因名称未给出]（76.2%）和[具体毒力相关基因名称未给出]（52.4%）毒力相关基因的显著高流行率。在黏菌素耐药菌株中，聚集性大肠埃希菌（76%）是最常检测到的基因型。(4) 结论：在我们大学医院从医院获得性肺炎患者中分离的菌株中观察到的高黏菌素耐药率令人担忧。这些分离株携带不同的耐药和毒力相关基因。我们的结果表明在我们大学医院需要仔细监测黏菌素耐药性。此外，限制不必要使用超广谱头孢菌素和碳青霉烯类的感染控制政策是必要的。
