肺泡灌洗液菌量检测与肺炎支原体肺炎患儿临床特征的关系探讨

Relationship between bronchoalveolar lavage fluid Mycoplasma load and clinical characteristics in children with Mycoplasma pneumoniae pneumonia

目的 评价肺炎支原体肺炎患儿肺泡灌洗液病菌量与临床特征的相关性.方法 应用荧光实时定量PCR对67例肺炎支原体肺炎患儿肺泡灌洗液进行肺炎支原体DNA定量检测,并根据其基因拷贝数分为低菌量组（＜ 103/ml,21例）,中等菌量组（103 ～ 106/ml,22例）和高菌量组（＞106/ml,24例）,比较不同组患儿的临床症状及主要实验室与影像学结果.结果 高菌量组总热程[（12.4±2.7）d]明显比低菌量组[（7.4±2.6）d]及中等菌量组[（10.0±2.4）d]更长,且高热患儿更多,使用大环内酯类后热程也更长[（10.8±4.4）,（8.5±2.4）,（4.2±1.0）d],差异有统计学意义（P＜0.05）.三组患儿C反应蛋白分别为（34.0±10.1）,（11.5±7.6）,（3.0±1.4） mg/L,差异有统计学意义（P=0.004）.高菌量组患儿影像学表现为大片肺实变/不张影者58.3％（14/24）,明显多于中等菌量组的22.7％（5/22）和低菌量组的14.3％ （3/21）（P=0.002）.低菌量组未见双侧胸腔积液或大量胸腔积液,中等菌量组和高菌量组分别为13.6％（3/22）和25.0％（6/24）（P=0.033）.结论 肺炎支原体肺炎儿童肺泡灌洗液病菌量与临床特征有一定的相关性,高菌量患儿病情更为严重.

Objective To explore the relationship between bronchoalveolar lavage fluid （BALF） Mycoplasma load and clinical characteristics in children with Mycoplasma pneumoniae （MP） pneumonia.Methods MP DNA was quantitatively detected by fluorescent real-time PCR in BALF from 67 children with MP pneumonia.They were classified into three groups：low MP load group （〈 103/ml,21 cases）,moderate MP load group （103-106/ml,22 cases） and high MP load group （〉 106/ml,24 cases）.Clinical symptom,main laboratory and imaging results of children among three groups were compared.Results When compared with low MP load group and moderate MP load group,high MP load group had longer fever duration [（7.4 ± 2.6）,（10.0 ± 2.4） d vs.（12.4 ± 2.7） d],longer time to normalization of temperature with macrolide administration [（4.2 ± 1.0）,（8.5 ± 2.4） d vs.（10.8 ± 4.4） d],more patients with high fever,there was significant difference （P 〈 0.05）.Statistically significant difference existed in C-reactive protein among three groups [（3.0 ± 1.4）,（11.5 ±7.6）,（34.0 ± 10.1） mg/L] （P =0.004）.Large field of consolidation or atelectasis were found in 58.3% （14/24） of high MP load group,much higher than 22.7% （5/22） in moderate MP load group and 14.3% （3/21） in low MP load group.Bilateral or massive pleural effusion was not found in low MP load group,while in moderate MP load and high MP load group,they were 13.6 % （3/22） and 25.0% （6/24）（P =0.033）.Conclusions There is a close relationship between MP load in BALF and clinical characteristics in children with MP pneumonia.Those with high MP load have a more severe process.