呼吸道流感嗜血杆菌的生物学分型与耐药基因的相关性研究

摘要

目的：了解本院临床分离流感嗜血杆菌的生物学分型及耐药基因，为临床合理用药提供依据。方法：收集呼吸道感染病人的痰液和咽拭子，用手工法和MicSCAN4全自动细菌鉴定分析仪，HNID鉴定板对分离培养的110株流感嗜血杆菌进行菌种鉴定并进行生物学分型。用纸片琼脂扩散（K-B）法进行药敏试验，采用头孢硝噻吩纸片法进行β内酰胺酶检测，PCR方法进行耐药基因的检测。结果：临床分离110株流感嗜血杆菌，共检出Ⅰ、Ⅱ、Ⅲ、Ⅳ、Ⅴ、Ⅵ、Ⅶ型7种生物型，未检出Ⅷ型，以Ⅱ、Ⅲ型为主，分别是生物Ⅱ型38株（34.5%），生物Ⅲ型46株（41.8%），共有45株检出TEM基因和ROB基因，分别占93.3%、6.7%。冬季感染率最高。流感嗜血杆菌对氨苄西林耐药率为40.9%，β内酰胺酶株产酶率为40.9%。对头孢呋辛、头孢噻肟、氯霉素的敏感率都在90%以上，未检出美罗培南耐药菌株。结论：呼吸道流感嗜血杆菌感染好发于冬季，感染的生物型均以生物Ⅱ型、生物Ⅲ型为主，对氨苄西林和甲氧苄啶-磺胺甲噁唑的耐药率较高，已不宜用于流感嗜血杆菌引起感染的经验治疗。Hi对氨苄西林的耐药主要是产生β内酰胺酶，且主要为TEM-1型。对该菌所致呼吸道感染可选用头孢呋辛、头孢噻肟、美罗培南作为治疗的首选药物。%Objective:To investigatethe biotype and resistant gene of clinical isolated haemophilus,so as to guide the rational use of antibiotics in clinic. Methods:He sputum and throat swab were collected from respiratory tract infact patients.strain identification and biotype of 110 cases of haemophilus were conducted using the MicSCAN4 analytic instrument .Antimicrobial susceptibility were tested by Kirby-Bauer method, and Beta lactamases were detected by nitrocefin filter paper method,The resistance gene were detected by polymerase chain reaction(PCR).Results:Seven biotypes (Ⅰ、Ⅱ、Ⅲ、Ⅳ、Ⅴ、Ⅵ、Ⅶ) were detected among 110 cases of clinical isolated haemophilus,The main types were type Ⅱ (38strains,34.5%)and type Ⅲ (46 strains, 41.8%),and typeⅧwas not detected.a total of 45 strains of TEM gene and ROB gene were detected, 93.3%as TEM gene, 6.7%as ROB gene. winter infection rate was the highest.Drug resistance of the strains agains ampicillin was 40.9%, The prevalence of beta lactamase of all strains was 40.9%. The drug resistance rate to cefotaxime,cefuroxime and chloramphenicol was over 90%.,the resistant strain was not detected to meropenem. Conclusions:The respiratory tract infections of Haemophilus influenzae were more prevalent in winter and TrpyⅡand typeⅢwere the most prevalent types.The drug resistance of Haemophilus influenzae to ampicillin and trimethoprim-sulfamethoxazole is increasing ,should not be used as an empirical treatment of Haemophilus infection. suggesting that the cefotaxime , cefuroxime and meropenem could serve as an ideal option for the treatment.