烧伤患者感染产ESBLs鲍曼不动杆菌的耐药特性及耐药基因型分析

Analysis of drug resistance and genotyping of ESBL-producing Acinetobacter baumannii infecting patients with burns

目的分析烧伤患者感染产超广谱β-内酰胺酶(ESBLs)鲍曼不动杆菌的耐药特性及其耐药基因类型。方法采用纸片扩散法(KB法)测定分离自烧伤患者临床标本的137株鲍曼不动杆菌中产ESBLs菌株对β-内酰胺类抗生素的耐药特征,应用聚合酶链反应(PCR)进行细菌的ESBLs基因分型。结果 37株鲍曼不动杆菌对β-内酰胺类抗生素呈不同程度的耐药。检出产ESBLs菌84株,占61.31%。产ESBLs菌株对哌拉西林、替卡西林、氨苄西林/舒巴坦、头孢噻肟、头孢曲松、头孢他啶、头孢吡肟、氨曲南的耐药率分别为83.33%、88.10%、96.43%、89.29%、85.42%、86.90%、77.38%和89.29%,与非产ESBLs菌株耐药率50.94%~77.36%比较差异有统计学意义(P<0.05);30株产ESBLs菌株中,仅携带TEM、SHV、OXA-23及PER型基因的分别有12株(40.00%)、4株(13.33%)、7株(23.33%)和2株(6.67%),其余5株中有3株(10.00%)同时携带TEM和OXA-23型两种基因,2株(6.67%)同时携带TEM、OXA-23和PER型3种基因。结论烧伤患者感染的产ESBLs鲍曼不动杆菌具有多重耐药性,耐药基因型包括TEM、SHV、OXA-23和PER型。

Objectives To analyze the drug resistance and to genotype extended-spectrum beta lactamase（ESBL）-producing Acinetobacter baumannii infecting patients with burns. Methods One hundred and thirty-seven strains of ESBLproducing A.baumannii were isolated from patients with burns,and the drug resistance of ESBL-producing strains to β-lactam antibiotics was detected using the Kirby-Bauer method.The genotypes of the strains were determined using apolymerase chain reaction（PCR）. Results The 137 strains of A.baumannii had different levels of resistance toβ-lactam antibiotics.Of the strains,84（61.31%） were ESBL-producing A.baumannii.The resistance of ESBL-producing strains to piperacillin（PIC）was 83.33%,their resistance to ticarcillin（TIC）was 88.10%,their resistance to ampicillin/sulbactam（FAM）was 96.43%,their resistance to cefotaxime（CTX）was 89.29%,their resistance to ceftriaxone（CRO）was 85.42%,their resistance to ceftazidime（CAZ）was 86.90%,their resistance to cefepime（FEP）was 77.38%,and their resistance to aztreonam（ATM）was 89.29%.The resistance of ESBL-producing strains was significantly higher than that of non-ESBL-producing strains,which had resistance ranging from 50.94% to 77.36%（P〈0.05）.Of the 30 ESBL-producing strains,12（40.00%） were the TEM genotype,4（13.33%） were SHV,7（23.33%） were OXA-23,and 2（6.67%）were PER.The 5 remaining ESBL-producing strains included 3（10.00%） with both the TEM and OXA-23 genotypes and 2（6.67%）with the TEM,OXA-23,and PER genotypes. Conclusion ESBL-producing A.baumannii infecting patients with burns has multidrug resistance,and its drug resistance genotypes included TEM,SHV,OXA-23,and PER.