杭州市上呼吸道感染患儿分离的流感嗜血杆菌分离株的血清分型及其对氨苄西林的耐药性分析

Serotypes and ampicillin resistance of Haemophilus influenzae isolates from children with respiratory infection in Hangzhou

摘要:

目的：了解从呼吸道感染患儿分离出的流感嗜血杆菌血清分型及其对氨苄西林耐药性。方法：流感嗜血杆菌的鉴定采用V因子，X因子和V+X因子试验，血清分型采用玻片凝集法，β内酰胺酶检测采用头孢硝噻酚法，药敏试验采用纸片扩散法和E-test法。结果：2006年12月至2007年7月共分离到的流感嗜血杆菌152株，其中男性患儿108株，占71.0%，女性患儿44株，占29.0%。血清分型显示不可分型流感嗜血杆菌148株，占97.4%，可分型流感嗜血杆菌4株，占2.6%；可分型菌株中，a，d，e，f型各1株，无b，c型菌株发现。34株菌株(22.4%) 产生β内酰胺酶。152株流感嗜血杆菌中，全部菌株成功完成药敏试验，113株菌株(74.3%)对氨苄西林敏感；141株菌株用E-test法检验了最低抑菌浓度（MIC），氨苄西林MIC50为0.25 μg/mL，MIC90为12 μg/mL。结论：该研究中流感嗜血杆菌分离株以不可分型菌株占绝对优势，74.3%流感嗜血杆菌对氨苄西林敏感。［中国当代儿科杂志，2009，11（3）：217-220］

Abstract:

OBJECTIVE: To investigate the serotypes distribution and ampicillin resistance of Haemophilus influenzae isolates from children with respiratory infection in Hangzhou. METHODS: Haemophilus influenzae strains were identified with V factor and X factor tests. Serotypes were determined with the slide agglutination method. Nitrocefin test was used to detect β-lactamase. The sensitivities of ampicillin to Haemophilus influenzae were determined with the Kirby-Bauer diffusion method and the E-test method. RESULTS: One hundred and fifty-two Haemophilus influenzae isolates, 108 from boys and 44 from girls, were identified between December 2006 and July 2007. Of the 152 isolates, 148 (97.4%) were untypable, only 4 (2.6%) were typable, including type a, type d, type e and type f (n=1 each type). Haemophilus influenzae type b and c strain was not found. Thirty-four isolates (22.4%) were β-lactamase-positive. One hundred and thirteen isolates (74.3%) were susceptible to ampicillin, while 34 isolates (22.4%) were resistant to ampicillin. CONCLUSIONS: Untypable strains were the most common in Haemophilus influenzae isolates from children with respiratory infection in Hangzhou. The isolates of Haemophilus influenzae kept susceptibity to ampicillin to a certain extent.［Chin J Contemp Pediatr, 2009, 11 (3):217-220］