Objective: Increasing the emergence of Metallo-β-lactamase (MBL) producing gram-negative bacteria and their dexterous horizontal transmission demands rapid and accurate detection. This study was conducted to determin...Objective: Increasing the emergence of Metallo-β-lactamase (MBL) producing gram-negative bacteria and their dexterous horizontal transmission demands rapid and accurate detection. This study was conducted to determine a suitable method to promptly detect MBL-producing gram-negative bacteria. Methods: A total of 103 gram-negative bacteria were identified from various clinical samples at a tertiary care hospital in Dhaka city. MBL producers were detected by two phenotypic methods, the Disk Potentiation Test (DPT) and the Double Disk Synergy Test (DDST) based on β-lactam chelator combinations where EDTA/SMA has been used as an inhibitor and Imipenem, Ceftazidime as substrates. Results: 103 isolates which were identified as Escherichia coli spp, Klebsiella spp, Pseudomonas spp, Acinetobacter spp, Proteus spp, Providencia spp were found to be multidrug-resistant in antibiogram test. Isolates showed complete resistance (100%) to Imipenem, Meropenem, and Amoxiclav. The highest carbapenem-resistant etiological agents were Acinetobacter spp 40 (38.8%) followed by Pseudomonas spp 27 (26.2%), Klebsiella spp 26 (25.2%), Escherichia coli 8 (7.8%), Proteus spp 1 (1%) and Providencia spp 1 (1%). DPT method detected significantly (p = 0.000009) a higher number of MBL-producers (Imipenem with 0.5 M EDTA n = 61, 59.2% & Ceftazidime with 0.5 M EDTA n = 56, 54.4%) compared to the DDST method (Imipenem -0.5 M EDTA n = 43, 41.7%, Imipenem – SMA n = 38, 36.9% & Ceftazidime -0.5 M EDTA n = 15, 14.6%). Conclusion: Pieces of evidence suggest that DPT is a more sensitive method than DDST and could be recommended for identifying MBL-producing bacteria in Bangladeshi hospitals for the proper management of patients, to reduce time constraints and treatment costs.展开更多
采用巢式PCR、DNA测序和CRS-PCR方法,研究中国荷斯坦牛、鲁西黄牛、渤海黑牛的MBL1基因内含子1和外显子2的单核苷酸多态性(SNPs),发现了855(G/A)、2651(G/A)和2686(T/C)3个新SNP位点。855(G/A)位于内含子1上,2651(G/A)导致Val24 Ile氨...采用巢式PCR、DNA测序和CRS-PCR方法,研究中国荷斯坦牛、鲁西黄牛、渤海黑牛的MBL1基因内含子1和外显子2的单核苷酸多态性(SNPs),发现了855(G/A)、2651(G/A)和2686(T/C)3个新SNP位点。855(G/A)位于内含子1上,2651(G/A)导致Val24 Ile氨基酸的改变,2686(T/C)为同义突变。3个SNP位点在3个牛品种群体中优势等位基因相同,分别为G、G、C,其等位基因频率分别为0.87/0.58/0.57、1/0.75/0.74、1/0.76/0.63。经χ2适合性检验,荷斯坦牛在855(G/A)位点、鲁西黄牛在855(G/A)、2651(G/A)位点、渤海黑牛的所有位点达到Hardy-W e inberg平衡状态(P>0.05)。3个牛品种在855(G/A)位点均表现为低度多态;在2651(G/A)和2686(T/C)位点均表现为中度多态(0.25<PIC<0.5)。展开更多
文摘Objective: Increasing the emergence of Metallo-β-lactamase (MBL) producing gram-negative bacteria and their dexterous horizontal transmission demands rapid and accurate detection. This study was conducted to determine a suitable method to promptly detect MBL-producing gram-negative bacteria. Methods: A total of 103 gram-negative bacteria were identified from various clinical samples at a tertiary care hospital in Dhaka city. MBL producers were detected by two phenotypic methods, the Disk Potentiation Test (DPT) and the Double Disk Synergy Test (DDST) based on β-lactam chelator combinations where EDTA/SMA has been used as an inhibitor and Imipenem, Ceftazidime as substrates. Results: 103 isolates which were identified as Escherichia coli spp, Klebsiella spp, Pseudomonas spp, Acinetobacter spp, Proteus spp, Providencia spp were found to be multidrug-resistant in antibiogram test. Isolates showed complete resistance (100%) to Imipenem, Meropenem, and Amoxiclav. The highest carbapenem-resistant etiological agents were Acinetobacter spp 40 (38.8%) followed by Pseudomonas spp 27 (26.2%), Klebsiella spp 26 (25.2%), Escherichia coli 8 (7.8%), Proteus spp 1 (1%) and Providencia spp 1 (1%). DPT method detected significantly (p = 0.000009) a higher number of MBL-producers (Imipenem with 0.5 M EDTA n = 61, 59.2% & Ceftazidime with 0.5 M EDTA n = 56, 54.4%) compared to the DDST method (Imipenem -0.5 M EDTA n = 43, 41.7%, Imipenem – SMA n = 38, 36.9% & Ceftazidime -0.5 M EDTA n = 15, 14.6%). Conclusion: Pieces of evidence suggest that DPT is a more sensitive method than DDST and could be recommended for identifying MBL-producing bacteria in Bangladeshi hospitals for the proper management of patients, to reduce time constraints and treatment costs.
文摘采用巢式PCR、DNA测序和CRS-PCR方法,研究中国荷斯坦牛、鲁西黄牛、渤海黑牛的MBL1基因内含子1和外显子2的单核苷酸多态性(SNPs),发现了855(G/A)、2651(G/A)和2686(T/C)3个新SNP位点。855(G/A)位于内含子1上,2651(G/A)导致Val24 Ile氨基酸的改变,2686(T/C)为同义突变。3个SNP位点在3个牛品种群体中优势等位基因相同,分别为G、G、C,其等位基因频率分别为0.87/0.58/0.57、1/0.75/0.74、1/0.76/0.63。经χ2适合性检验,荷斯坦牛在855(G/A)位点、鲁西黄牛在855(G/A)、2651(G/A)位点、渤海黑牛的所有位点达到Hardy-W e inberg平衡状态(P>0.05)。3个牛品种在855(G/A)位点均表现为低度多态;在2651(G/A)和2686(T/C)位点均表现为中度多态(0.25<PIC<0.5)。