90例2岁以下百日咳疑似患儿病原学及临床特征分析

Analysis of etiology and clinical manifestations of 90 patients with suspected pertussis under 2 years old

目的了解2岁以下百日咳疑似患儿的病原学及临床特征。方法前瞻性纳入2015年7月到2016年6月收住的2岁以下百日咳疑似患儿90例，收集鼻咽分泌物及临床资料。PCR法检测百日咳鲍特菌，阳性为百日咳组，阴性为百日咳综合征组，检测13种呼吸道病毒和不典型病原体，并做细菌培养。对比两组患儿病原学及临床特征。组间正态分布计量资料比较采用独立样本t检验，计数资料比较采用χ2检验。结果共纳入百日咳疑似患儿90例，其中男46例，女44例，年龄33 d～18个月，中位年龄3个月。35例（38.9%）百日咳鲍特菌PCR检测结果阳性（百日咳组），年龄34 d～13个月，中位年龄2个月；55例（61.1%）检测结果阴性（百日咳综合征组），年龄33 d～18个月，中位年龄4个月。百日咳组发病前1个月内有住院病史的比例高于百日咳综合征组，比较差异有统计学意义（χ2＝4.496，P〈0.05）。百日咳组较百日咳综合征组更易出现发绀及夜间咳嗽（χ2值分别为4.234和10.960，均P〈0.05），且百日咳患儿病程长于百日咳综合征患儿（t＝3.402，P〈0.05）。百日咳组白细胞计数为（22.00±9.42）×109/L，百日咳综合征组为（16.31±8.10）×109/L，两组比较差异有统计学意义（t＝3.049，P〈0.05）。两组检出甲型流感病毒分别为22和44例、鼻病毒分别为16和25例、副流感病毒分别为5和12例、呼吸道合胞病毒分别为3和6例。结论百日咳疑似患儿若有阵发性发绀、咳嗽夜间为主且白细胞计数升高明显，百日咳可能性大。本地区2岁以下百日咳疑似患儿中除百日咳鲍特菌感染外，流感病毒A、鼻病毒、副流感病毒等病毒是常见病原，且常合并存在。

ObjectiveTo investigate the etiology and clinical manifestations of patients with suspected pertussis under 2 years old. MethodsA total of 90 patients under 2 years old with suspected pertussis were collected prospectively from July 2015 to June 2016.Nasopharyngeal secretions and clinical data were obtained. Bordetella pertussis was detected by polymerase chain reaction （PCR）. Patients were classified into pertussis group if the PCR was positive, or pertussis syndrome group if negative. Other 13 respiratory viruses and atypical pathogens were also detected, and bacterial culture was performed. Pathogens and clinical manifestations were compared between groups. For normal distributed data, continuous variables between groups were compared using two-sample t-test, while categorical variables between groups were compared using chi-square test.ResultsA total of 90 suspected cases were included, including 46 males and 44 females. Age ranged from 33 days to 18 months, and the median age was 3 months. Thirty-five cases （38.9%） were positive for Bordetella pertussis PCR （the pertussis group）, the age ranged from 34 days to 13 months, the median age was 2 months. Fifty-five cases （61.1%） were negative （the pertussis syndrome group）, with the age ranging from 33 days to 18 months, and the median age was 4 months. In pertussis group, there was a higher percentage of hospitalization history in 1 month before onset than that of the pertussis syndrome group, and the difference was statistically significant （χ2=4.496, P〈0.05）. Patients in pertussis group were more likely to have cyanosis and cough at night （χ2= 4.234 and 10.960, both P〈0.05）, and the course of pertussis was longer than that in pertussis syndrome （t=3.402, P〈0.05）. The length of hospital stay before pertussis onset in pertussis group was longer than that in the pertussis syndrome group （P〈0.05）. The mean white blood count in pertussis group was （22.00±9.42）×109/L, and that in pertussis syndrome group was （16.31±8.10）×109/L, and the difference between the two groups was statistically significant （t=3.049, P〈0.05）. In pertussis group and pertussis syndrome group, influenza virus A was detected in 22 and 44 cases, respectively; rhinovirus in 16 and 25 cases, respectively; parainfluenza virus in 5 and 12 cases, respectively; respiratory syncytial viruses in 3 and 6 cases, respectively.ConclusionsPatient who presents with cyanosis, cough at night and high white blood cell count is more likely to have pertussis. Influenza viruses A, humanrhinovirus and human parainfluenza viruses are common pathogens to be found in patients with suspected pertussis under 2 years of age.