Little is known about the molecular basis of antibiotic resistance among uropathogens in Southeast Nigeria. The aim of the study was to characterize enterobacterial uropathogens with respect to drug resistance. One hundred (100) enterobacterial uropathogens were studied. Their antibiotic susceptibility patterns were evaluated using disk diffusion, screened, and confirmed phenotypically for the presence of β-lactamases: ESBL, AmpC, carbapenemase, and MBLs. Screen positives were further tested for various β-lactamase genes by PCR. Our isolates showed variable resistance to most drugs tested. Out of the 58 ESBL screen positive E. coli, 35 were confirmed positive with PCR. The predominant ESBL gene was bla_TEM while bla_SPM was the most prevalent among MBL genes. Forty-six percentage of the screen positive Salmonella isolates coharbored bla_{TEM + SHV} genes. Nine of the 10 ESBL screen positive K. pneumoniae were phenotypically and PCR positive. Three isolates of K. pneumoniae were positive for MBL genes. All the 10 C. freundii were positive for ESBL genes. The study showed high prevalence of drug-resistant genes among the enterobacterial uropathogens. Majority of the uropathogens harbored >1 antibiotic-resistant gene, and the most predominant gene was ESBL (bla_TEM) followed by the MBL (SPM) gene.

中文翻译：

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尼日利亚东南部肠杆菌尿路病原体中β-内酰胺酶的表型和分子特征

关于尼日利亚东南部尿路病原体抗生素耐药性的分子基础知之甚少。该研究的目的是表征肠杆菌尿路病原体的耐药性。研究了一百 (100) 种肠杆菌尿路病原体。他们的抗生素敏感性模式使用纸片扩散进行评估、筛选，并通过表型确认是否存在β-内酰胺酶：ESBL、AmpC、碳青霉烯酶和 MBL。通过 PCR进一步测试各种β-内酰胺酶基因的筛选阳性。我们的分离株对大多数测试药物表现出不同的耐药性。在 58 个 ESBL 筛选阳性大肠杆菌中， 35 个通过 PCR 确认为阳性。主要的 ESBL 基因是 bla _TEM而 bla _SPM在 MBL 基因中最为普遍。百分之四十六的筛选阳性沙门氏菌分离出共存的 bla _{TEM + SHV}基因。10 个 ESBL 筛查呈阳性的肺炎克雷伯菌中有 9 个在表型和 PCR 上呈阳性。三株肺炎克雷伯菌的 MBL 基因呈阳性。所有 10 个 C. freundii都是 ESBL 基因阳性。该研究表明，肠道细菌尿路病原体中耐药基因的流行率很高。大多数尿路病原体携带 >1 个抗生素耐药基因，最主要的基因是 ESBL (bla _TEM )，其次是 MBL (SPM) 基因。