难治性支原体肺炎MP-DNA拷贝数与激素疗效的关联研究

Study on MP-DNA copy number and glucocorticoid efficacy of refractory Mycoplasma pneumonia

目的探讨难治性肺炎支原体肺炎(RMPP)患儿支气管肺泡灌洗液(BALF)中肺炎支原体基因(MP-DNA)拷贝数与甲泼尼龙常规剂量疗效的关系,以期为早期识别常规剂量甲泼尼龙治疗无效的病例提供依据。方法选取2018年1月至2019年12月于西安市儿童医院呼吸一科住院治疗的72例RMPP患儿为研究对象,对其临床资料进行回顾性分析。甲泼尼龙1~2mg·kg^(-1)·d^(-1)为常规剂量组,该剂量不能控制体温或者初始量即为4 mg·kg^(-1)·d^(-1)定义为高剂量组。MP-DNA拷贝数<1.0×10^(7)/mL为中低拷贝组,≥1.0×10^(7)/mL为高拷贝组。结果72例患儿的BALF中,MP-DNA拷贝数最低为4.6×10^(3)/mL,最高为1.93×10^(8)/mL,当BALF中MP-DNA拷贝数≥10^(7)/mL时,使用高剂量甲泼尼龙的比例明显上升,差异有统计学意义(χ^(2)=4.753,P<0.05);高拷贝组及中低拷贝组患儿性别、年龄、热程、入院后热程、呼吸困难比例及发病至采集灌洗液检测的时间比较差异无统计学意义(P>0.05),但高拷贝组住院时间长于中低拷贝组(t=2.871,P<0.05),出现胸腔积液比例高于中低拷贝组,差异有统计学意义(P_(Fisher)<0.05);实验室检查方面,高拷贝组的血清铁蛋白、D-二聚体均高于中低拷贝组,而外周血Ts细胞比例低于中低拷贝组,差异均有统计学意义(t值分别为2.408、2.450、-6.002,P<0.05)。结论RMPP患儿BALF中MP-DNA拷贝数达10^(7)/mL及以上时,甲泼尼龙初始剂量应考虑提高到4 mg·kg^(-1)·d^(-1)。

Objective To investigate the relationship between the copy number of Mycoplasma pneumoniae gene(MP-DNA)in bronchoalveolar lavage fluid(BALF)and the efficacy of conventional dose of methylprednisolone in children with refractory Mycoplasma pneumoniae pneumonia(RMPP),so as to provide basis for early identification of cases with ineffective treatment of conventional dose of methylprednisolone.Methods 72 children with RMPP hospitalized in the first respiratory department of Xi′an children′s Hospital from January 2018 to December 2019 were selected as the research objects,and their clinical data were analyzed retrospectively.Methylprednisolone 1-2 mg·kg^(-1)·d^(-1)was the conventional dose group.This dose failed to control the body temperature or the initial dose was 4 mg·kg^(-1)·d^(-1),which was defined as the high dose group.MP-DNA copy number<1.0×10^(7)/mL is medium and low copy group,and≥1.0×10^(7)/mL is the high copy group.Results Among 72 children with BALF,the copy number of MP-DNA was the lowest,which was 4.6×10^(3)/ml,up to 1.93×10^(8)/ml.When the copy number of MP-DNA in BALF was≥10^(7)/mL,the proportion of high-dose methylprednisolone increased significantly,and the difference was statistically significant(χ^(2)=4.753,P<0.05).There was no significant difference in gender,age,heat course,heat course after admission,dyspnea ratio and time from onset to collection of lavage fluid in high copy group and low copy group(P>0.05).But the hospitalization time in high copy group was longer than that in low copy group(t=2.871,P<0.05),and the proportion of pleural effusion in high copy group was higher than that in low copy group,the difference was statistically significant(P_(Fisher)<0.05).In terms of laboratory examination,serum ferritin and D-dimer in high copy group were higher than those in medium and low copy group,while the proportion of Ts cells in peripheral blood was lower than that in medium and low copy group,the differences were statistically significant(t=2.408,2.450,and-6.002,respectively,P<0.05).Conclusion When the copy number of MP-DNA in BALF of children with RMPP reaches 10^(7)/mL or above,the initial dose of methylprednisolone should be increased to 4 mg·kg^(-1)·d^(-1).