Zomorodi Abolfazl Rafati, Motamedifar Mohammad, Rahmanian Karamatollah, Shakeri Masihollah, Hajikhani Bahareh, Heidari Hamid, Mansury Davood, Jahromi Abdolreza Sotoodeh
Department of Bacteriology and Virology, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran.
Student Research Committee, Shiraz University of Medical Sciences, Shiraz, Iran.
BMC Infect Dis. 2024 Dec 18;24(1):1430. doi: 10.1186/s12879-024-10311-5.
Rising methicillin-resistant Staphylococcus aureus (MRSA) poses a global health threat, contributing to serious infections with high mortality rates. Integrons are recognized as significant genetic elements in disseminating multidrug-resistant (MDR) strains. This study focuses on assessing the prevalence of integron classes 1, 2, and 3 in S. aureus strains from four major cities in Iran.
This cross-sectional study analyzed 183 S. aureus isolates from Shiraz, Tehran, Isfahan, and Yazd in Iran. The isolates were identified using specific biochemical and molecullar tests. The Kirby-Bauer disc diffusion method and microbroth dilution method were employed to determine the susceptibility of the isolates to relevant antibiotics and vancomycin, respectively. The macrolide-lincosamide-streptogramin B (MLS) resistance phenotype was also evaluated using the D-test. All isolates were sought for presence of the intI1, intI2, and intI3 genes.
Among 183 S. aureus isolates, high resistance rates were noted: 86.3% for erythromycin, 66.1% for ciprofloxacin, and 61.7% for clindamycin, while all isolates were susceptible to linezolid and vancomycin. Of the 183 isolates, 59.6% were identified as MRSA and 78.1% as MDR. According to the D-test results, 112/183 (61.2%), 29/183 (15.8%), 25/183 (13.7%), and 17/183 (9.7%) of S. aureus isolates showed constitutive resistance-MLS, inducible resistance-MLS, sensitive, and resistance to macrolide-streptogramin B (MS) phenotypes, respectively. The intI1 gene was found in 14 out of 183 S. aureus isolates (7.6%), while none were positive for the intI2 or intI3 genes. Notably, 11/14 (78.5%) and 13/14 (92.8%) intI1-positive isolates were MRSA and MDR, respectively.
The distribution of MRSA and MDR S. aureus isolates in Iran seems concerning. Although the prevalence of intI1 was not as high as in prior studies, almost all S. aureus harbored the intI1 gene were MRSA and MDR.
耐甲氧西林金黄色葡萄球菌（MRSA）的不断增加对全球健康构成威胁，可导致严重感染且死亡率很高。整合子被认为是传播多重耐药（MDR）菌株的重要遗传元件。本研究聚焦于评估伊朗四个主要城市的金黄色葡萄球菌菌株中1类、2类和3类整合子的流行情况。
这项横断面研究分析了来自伊朗设拉子、德黑兰、伊斯法罕和亚兹德的183株金黄色葡萄球菌分离株。通过特定的生化和分子检测来鉴定这些分离株。分别采用 Kirby-Bauer 纸片扩散法和微量肉汤稀释法来测定分离株对相关抗生素和万古霉素的敏感性。还使用 D 试验评估大环内酯 - 林可酰胺 - 链阳霉素 B（MLS）耐药表型。对所有分离株进行intI1、intI2和intI3基因检测。
在183株金黄色葡萄球菌分离株中，观察到较高的耐药率：红霉素耐药率为86.3%，环丙沙星为66.1%，克林霉素为61.7%，而所有分离株对利奈唑胺和万古霉素敏感。在183株分离株中，59.6%被鉴定为MRSA，78.1%为MDR。根据D试验结果，金黄色葡萄球菌分离株中分别有112/183（61.2%）、29/183（15.8%）、25/183（13.7%）和17/183（9.7%）表现为组成型耐药 - MLS、诱导型耐药 - MLS、敏感以及对大环内酯 - 链阳霉素B（MS）耐药表型。在183株金黄色葡萄球菌分离株中有14株（7.6%）检测到intI1基因，而intI2或intI3基因均为阴性。值得注意的是，intI1阳性分离株中分别有11/14（78.5%）和13/14（92.8%）为MRSA和MDR。
伊朗MRSA和MDR金黄色葡萄球菌分离株的分布情况似乎令人担忧。尽管intI1的流行率不如先前研究高，但几乎所有携带intI1基因的金黄色葡萄球菌都是MRSA和MDR。
