Sah Ram Shankar Prasad, Dhungel Binod, Yadav Binod Kumar, Adhikari Nabaraj, Thapa Shrestha Upendra, Lekhak Binod, Banjara Megha Raj, Adhikari Bipin, Ghimire Prakash, Rijal Komal Raj
Central Department of Microbiology, Tribhuvan University, Kirtipur, Kathmandu 44618, Nepal.
Shahid Gangalal National Heart Centre, Bansbari, Kathmandu 44618, Nepal.
Diseases. 2021 Feb 7;9(1):15. doi: 10.3390/diseases9010015.
Antimicrobial resistance (AMR) among Gram-negative pathogens, predominantly ESBL-producing clinical isolates, are increasing worldwide. The main aim of this study was to determine the prevalence of ESBL-producing clinical isolates, their antibiogram, and the frequency of ESBL genes ( and ) in the clinical samples from patients.
A total of 1065 clinical specimens from patients suspected of heart infections were collected between February and August 2019. Bacterial isolates were identified on colony morphology and biochemical properties. Thus, obtained clinical isolates were screened for antimicrobial susceptibility testing (AST) using modified Kirby-Bauer disk diffusion method, while ESBL producers were identified by using a combination disk diffusion method. ESBL positive isolates were further assessed using conventional polymerase chain reaction (PCR) to detect the ESBL genes and .
Out of 1065 clinical specimens, 17.8% (190/1065) showed bacterial growth. Among 190 bacterial isolates, 57.4% (109/190) were Gram-negative bacteria. Among 109 Gram-negative bacteria, 40.3% (44/109) were , and 30.2% (33/109) were . In AST, 57.7% ( = 63) Gram-negative bacterial isolates were resistant to ampicillin and 47.7% ( = 52) were resistant to nalidixic acid. Over half of the isolates (51.3%; 56/109) were multidrug resistant (MDR). Of 44 , 27.3% (12/44) were ESBL producers. Among ESBL producer isolates, 58.4% (7/12) tested positive for the gene and 41.6% (5/12) tested positive for the gene.
Half of the Gram-negative bacteria in our study were MDR. Routine identification of an infectious agent followed by AST is critical to optimize the treatment and prevent antimicrobial resistance.
革兰氏阴性病原体中的抗菌药物耐药性（AMR），主要是产超广谱β-内酰胺酶（ESBL）的临床分离株，在全球范围内正在增加。本研究的主要目的是确定产ESBL临床分离株的流行率、它们的抗菌谱以及患者临床样本中ESBL基因（ 和 ）的频率。
2019年2月至8月期间，共收集了1065份疑似心脏感染患者的临床标本。根据菌落形态和生化特性鉴定细菌分离株。因此，使用改良的 Kirby-Bauer 纸片扩散法对获得的临床分离株进行抗菌药物敏感性试验（AST）筛查，同时使用联合纸片扩散法鉴定产ESBL菌株。对ESBL阳性分离株进一步采用常规聚合酶链反应（PCR）检测ESBL基因 和 。
在1065份临床标本中，17.8%（190/1065）显示有细菌生长。在190株细菌分离株中，57.4%（109/190）为革兰氏阴性菌。在109株革兰氏阴性菌中，40.3%（44/109）为 ，30.2%（33/109）为 。在AST中，57.7%（ = 63）的革兰氏阴性菌分离株对氨苄西林耐药，47.7%（ = 52）对萘啶酸耐药。超过一半的分离株（51.3%；56/109）为多重耐药（MDR）。在44株 中，27.3%（12/44）是产ESBL菌株。在产ESBL的 分离株中，58.4%（7/12）的 基因检测呈阳性，41.6%（5/12）的 基因检测呈阳性。
我们研究中一半的革兰氏阴性菌为多重耐药菌。对感染病原体进行常规鉴定并随后进行AST对于优化治疗和预防抗菌药物耐药性至关重要。
