山东临沂地区下呼吸道感染患者卡他布兰汉菌耐药性分析及bro基因分型检测

Antibiotic resistance and bro genotyping of Branhemella catarrhalis isolated from patients with lower respiratory tract infections in Linyi, Shandong province

目的：分析山东临沂地区下呼吸道感染患者痰液样本中分离的卡他布兰汉菌对常用抗菌药物的耐药性及bro基因分型对耐药性的影响。方法连续收集2010年1月至2014年12月山东省临沂市人民医院镜检合格的下呼吸道感染患者痰液样本，将其分别划线接种于4块不同琼脂培养基进行细菌分离培养及鉴定。对分离出的卡他布兰汉菌进行药敏试验和β-内酰胺酶检测，同时采用PCR扩增结合限制性内切酶分析法对分离株进行bro基因分型。采用χ^2检验比较不同bro基因型菌株对抗菌药物的耐药率。结果5年来共分离出497株卡他布兰汉菌，以冬季检出最多（共221株）。所有菌株对厄他培南和氯霉素完全敏感，对阿莫西林／克拉维酸和头孢呋辛耐药率较低（≤2.8％），对复方磺胺甲噁唑、红霉素和氨苄西林的耐药率较高，为47．6％-89．8％，且呈逐年增加趋势，但差异无统计学意义（P＞0．05）。共检出产β-内酰胺酶卡他布兰汉菌412株（412／497，82．9％），均为bro基因阳性菌株，bro基因阳性菌株对红霉素、复方磺胺甲噁唑、左氧氟沙星和氨苄西林的耐药率均高于bro阴性菌株（χ^2＝12．16、16．18、8．41和200．00，P＜0．05）。经bro基因分型发现，bro-1型菌株占94．9％（391／412），bro-2型菌株占5.1％（21／412），bro-1型与bro-2型菌株对常用抗菌药物的耐药率差异无统计学意义（P＞0．05）。结论临床分离卡他布兰汉菌产β-内酰胺酶阳性率较高，且多为bro-1型阳性株。菌株对碳青霉烯类抗菌药物、头孢菌素及β-内酰胺酶抑制剂敏感率较高，可作为治疗呼吸道卡他布兰汉菌感染的首选。

Objective To analyze the antibiotic resistance of Branhemella catarrhalis strains isolated from sputum specimens of patients with lower respiratory tract infections from Linyi, Shandong Province, and to explore the relationship between bro genotypes of the strains and their resistance to antibiotic agents.Methods Sputum specimens were colleted from the patients with lower respiratory tract infections in Linyi People ’ s Hospital from the January 2010 to December 2014.The specimens were inoculated into 4 different disks for bacterial isolation and cultivation.β-lactamase detection and drug sensitivity tests were performed, and PCR coupled with restriction endonuclease analysis was employed for bro genotyping.χ^2 test was used to compare drug resistance of strains with different bro genotypes.Results A total of 497 Branhemella catarrhalis strains were isolated in five years, among which 221 strains were isolated in winter.All strains were sensitive to ertapenem and chloramphenicol, and the resistance rates to amoxicillin/clavulanate and cefaclor were low （≤2.8%）.The strains were highly resistant to compound sulfamethoxazole, erythromycin and ampicillin （47.6%-89.8%）, and there was a trend of increasing resistance rates with the year, but no statistically significant difference was observed （ P 〉0.05 ） .β-lactamases was positive in 412 strains （82.9%）, and all of these strains were positive for bro gene, and＆amp;nbsp;the resistances to erythromycin, compound sulfamethoxazole, levofloxacin and ampicillin were higher in bro positive strains than those in bro negative strains （χ^2 =12.16, 16.18, 8.41 and 200.00,P〈0.05）.Among bro positive strains, 391 （94.9%） were of genotype bro-1, 21 （5.1%） were of genotype bro-2, and their resistance to antibiotic agents was not of statistical difference （ P 〉0.05 ）.Conclusions Most of Branhemella catarrhalis clinical isolates are β-lactamase producing strains, and bro-1 is the most common genotype.Strains are highly sensitive to carbapenems, cephalosporins andβ-Lactamaseinhibitors, which can be recommended for the treatment of Branhemella catarrhalis-related respiratory tract infections.