儿童急性下呼吸道细菌感染的病原分析

目的了解本地小儿急性下呼吸道感染的细菌病原学流行特点,流感嗜血杆菌疫苗的接种情况,为临床合理使用抗生素治疗及预防下呼吸道感染提供依据。方法收集2010年5月至2012年4月诊断为小儿急性下呼吸道感染的儿科住院患儿鼻咽抽吸物标本203份,做普通细菌、真菌培养及药敏和耐药性检测;同时做流感嗜血杆菌疫苗的接种情况调查。结果 203份标本中检出致病菌171份,总检出率84.24%,其中革兰阴性菌检出率为69.95%(142/203),革兰阳性菌检出率11.82%(24/203)。≤1岁组、～3岁组和﹥3岁组的致病菌检出率分别为94.56%(139/147)、69.23%(18/26)和46.67%(14/30),致病菌的检出率在各年龄组之间差异有统计学意义(χ2=12.52,P=0.028),3岁以内以革兰阴性菌为主。绝大部分的革兰阴性菌只对头孢三代敏感,革兰阳性菌只对万古霉素敏感。同期住院儿童流感嗜血杆菌疫苗的接种率为23.65%。结论小儿急性下呼吸道感染致病菌已由过去的革兰阳性菌为主逐渐转变为革兰阴性菌为主,年龄小的儿童急性下呼吸道感染以革兰阴性菌为主,应该加强对流感嗜血杆菌疫苗接种的宣教,提高流感嗜血杆菌疫苗和肺炎球菌结合疫苗的接种率。

Pathogenic analysis on acute lower respiratory tract infections in children

To investigate the epidemiological character of bacterial pathogens of acute lower respiratory tract infection (ALRTI) among local children and inoculation condition of haemophilus influenzae vaccine to provide evidences and instructions of treatment and prevention of children′s ALRTI for using antibiotics reasonably. Methods Two hundred and three nasopharyngeal aspirate specimens from hospitalized children diagnosed as ALRTI between May 2010 and April 2012 were collected. Ordinary cultures of bacteria and fungi were conducted; drug sensitivity and tolerance were detected; at the same time, inoculation condition of the haemophilus influenzae vaccine was surveyed.Results The pathogens were detected in 171 out of 203 specimens, and the total detection rate was 84.24%, in which 69.95% was Gram-negative bacteria, and 11.82% was Gram-positive bacteria. The pathogen detection rates were 94.56%、69.23% and 46.67%,respectively in children aged ≤1,>1-3 and >3 years, and the difference was statistical significant(χ2=12.52, P=0.028). Gram-negative bacteria infection was found mainly in children aged <3 years. Vast majority of Gram-negative bacteria were sensitive to the third generation cephalosporin, while vast majority of Gram-positive bacteria were sensitive to vancomycin. Haemophilus influenzae vaccine coverage rate was 23.65% in the hospitalized children at same period. Conclusion Pathogens of children’s ALRTI have gradually transformed from dominated Gram-positive bacteria in the past to Gram-negative bacteria as a principle in present. The younger children with ALRTI were more likely infected by Gram-negative bacteria. The propagation and education for inoculation of haemophilus influenzae vaccine should be strengthened. Meanwhile, vaccination rate of haemophilus influenzae and pneumococcal conjugate vaccine should be increased.