成都地区成人下呼吸道流感嗜血杆菌感染的研究

Prospective epidemiological study on the adults of lower respiratory tract infection with haemophilus influenzae in Chengdu area

目的 探讨成都地区成人住院患者下呼吸道流感嗜血杆菌（Hi）感染发生情况、流行菌株生物学分型和菌株耐药背景以及临床基本特征.方法 采用前瞻性流行病学断面研究方法,2013年11月至2014年10月对我国成都地区两家三级综合性医院（成都市第三人民医院和都江堰市医疗中心）18岁以上的下呼吸道感染住院患者的痰液进行细菌培养.总共100例患者,男78例,女22例,患者年龄29~93岁,平均年龄（69.09 ±13.79）岁.对Hi流行菌株进行生物学分型、PCR技术检测荚膜基因和药敏试验.所有数据用SPSS 20.0软件处理,计数资料以百分率（%）表示,两家医院病原菌分离阳性率、Hi分离阳性率、并发症、生物学分型等的比较采用χ2检验或Fisher确切概率法,行×列表以P〈0.05作为差异有统计学意义.结果 2013年11月至2014年10月两家医院18岁以上的下呼吸道感染住院患者痰培养病原菌检出率为46.71%（15447/33069）,其中100例痰培养检出Hi 101株,Hi检出率0.31%（101/33069）,Hi占下呼吸道感染病原菌构成比0.65%（101/15447）,经PCR鉴定全部为未分型Hi;生物学分型按检出率从高到底依次为Ⅰ型42.57%（43/101）、Ⅳ型29.7%（30/101）、Ⅱ型15.84%（16/101）、Ⅲ型9.9%（10/101）、Ⅶ型1.98%（2/101）和Ⅵ型0.9%（1/101）;Hi阳性疾病构成包括慢性阻塞性肺疾病急性发作期59%（59/100）,肺部感染35%（35/100）,支气管炎6%（6/100）;其中55%（55/100）为社区获得性感染;69%（69/100）的感染者存在其他并发症;病死率8%（8/100）;β-内酰胺酶产酶率38.61%（39/101）;β-内酰胺酶阴性氨苄西林耐药率2.97%（3/101）,中介率4.95%（5/101）;β-内酰胺酶阴性阿莫西林克拉维酸耐药率2.97%（3/101）;头孢呋辛耐药率16.83%（17/101）;头孢克洛耐药率38.6%（39/101）;头孢噻肟耐药率6.93%（7/101）;氧氟沙星耐药率1.99%（2/101）;上述抗生素耐药率两院比较差异均无统计学意义（P值均〉0.05）.结论 我国成都地区成人下呼吸道感染流感嗜血杆菌全部为不可分型,生物学分型以Ⅰ型、Ⅱ型、Ⅲ型和Ⅳ型为多见,出现氨苄西林耐药菌株以及氧氟沙星耐药菌株.

Objective To investigate the epidemic strains of biological type, drug resistance, and the basic clinical characteristics of haemophilus influenzae（Hi）isolated from hospitalized adults with lower respiratory tract infection in Chengdu area.Methods A prospective cross-sectional study was conducted to analyze the biological typing,capsular genes detected by PCR technique,and drug resistance tested by drug sensitive test of Hi epidemic strains isolated from the sputum of adults aged above 18 years who were hospitalized in two tertiary hospitals of west Sichuan in China.Results The positive rate of pathogenic bacteria in adults aged above 18 years who were hospitalized in the two hospitals was 46.71%（15 447/33 069）between November 2013 and October 2014.The positive rate of Hi isolated from the sputum of 100 adults with lower respiratory tract infection was 0.31%（101/33 069）.The constituent ratio of Hi in lower respiratory tract infection pathogens was 0.65%（101/15 447）.The Hi were all undifferentiated type detected by PCR,and the biological typing of Hi were typeⅠ（42.57%）,Ⅳ（29.7%）,Ⅱ（15.84%）,Ⅲ（9.9%）,Ⅶ（1.98%）, and Ⅵ（0.9%）.The diseases of Hi positive were acute phase of chronic obstructive pulmonary disease（59%）, pneumonia（35%）, and bronchitis（6%）, in which community acquired infection was 55%.The rate of β-lactamase enzyme production was 38.61%.The frequencice of β-lactamase -nonproducing-ampicillin-resistant（BLNAR）strains was 2.97%,and of intermediary strains was 4.95%（5/101）.The drug resistance rate of amoxicillin and clavulafiate was 2.97%.The drug resistance rate of cefuroxime was 12.87%, and intermediary rate was 12.87%.The drug resistance rate of cefaclor was 29.7%,and intermediary rate was 8.91%.The drug resistance rate of cefotaxime and ofloxacin was 6.93%and 1.99%.There were no obvious statistical differences between the drug resistance rates of the two hospitals.Conclusions The Hi epidemic strains isolated from the sputum of adults with lower respiratory tract infection were all undifferentiated type,and the common biological types were Ⅰ,Ⅳ,Ⅱ, andⅢ in west Sichuan in China.It should pay attention to the BLNAR strains and ofloxacin-resistant strains.