婴幼儿呼吸道合胞病毒肺炎和肺炎支原体肺炎患儿肺功能的研究及临床意义

目的探讨呼吸道合胞病毒(RSV)、肺炎支原体(MP)以及混合感染所致婴幼儿肺炎患儿的肺功能变化及其临床意义。方法选取于2005-10—2006-04因支气管肺炎于苏州大学儿童医院治疗的婴幼儿151例,运用直接免疫荧光法(DFA)和定量酶联免疫吸附试验(ELISA)分别检测肺炎患儿痰液中呼吸道合胞病毒和血清中肺炎支原体特异性抗体。采用瑞士ECOMEDICS公司的V’max26(EXHALYZER)肺功能仪对151例婴幼儿(根据年龄和病原不同分组)进行肺功能检测,观测患儿潮气呼吸流速容量环形态及其各项指标变化。结果呼吸道合胞病毒肺炎、肺炎支原体肺炎或两者混合感染患儿潮气流速容量环均变窄,呼气曲线升枝陡峭,呼气高峰提前,降枝呈波谷样凹陷。呼气峰流速因年龄不同而有所差异,1岁以内组肺炎患儿呼气峰流速增高(P<0.05),而～3岁组肺炎患儿呼气峰流速略降低(MP感染组P<0.05)。RSV、MP急性感染均表现为呼吸频率(RR)、潮气呼气峰流速/呼气量(PF/Ve)、潮气呼气峰流速/呼气达峰时间(PTEF/TPTEF)增加,每公斤潮气量(VT/kg)、呼气达峰时间比(TPTEF/TE)、呼出75%潮气量时呼气流速(TEF25%)、到达潮气呼气峰流速时呼气量(VPTEF),以及代表小气道功能的指标25/PF、%V-PF下降,与健康对照组比较差异均有显著性。反映大气道功能的指标潮气呼气中期流速/潮气吸气中期流速(ME/MI)差异无显著性。不同病原组间肺功能各指标差异无显著性。潮式呼吸参数用两样本均数t检验和多样本均数的方差分析。结论RSV和MP感染所引起的肺炎均能导致婴幼儿肺功能的损害,主要表现为小气道阻塞性改变。RSV和MP急性期感染之间肺功能损害程度并无显著区别,预后有无差别还有待于进一步的随访研究。TBFV环可作为评价临床上婴幼儿肺功能的损害程度的客观依据。

Pulmonary function changes in infants with respiratory syncytial virus or mycoplasma pneumoniae infection and clinical significance

Objective To discuss pulmonary function changes in infants with community-acquired pneumonia due to respiratory syncytial virus infection or mycoplasma pneumoniae infection or combined infection.Methods Applying microimmunofluorescence and quantitive enzyme-linked immunosorbent assay to detecting RSV in sputum and MP specific antibodies in serum.Observe the shape of tidal breathing flow-volume loops and changes of every index.TBFVLs were obtained for 151 infants at admission with a Pulmonary Testing System(Model V max 26,ECO Medics).The tidal breathing parameters were analyzed using T test and ANOVA.Results TBFVLs in infants due to RSV,MP or combined infection became narrow,the rising limb became more cliffy and the declined limb became trough-like concave.Peak tidal expiratory flow(PTEF)differed between the two age groups.During acute phase of RSV or MP infection,the respiratory rate,the ratio of peak tidal expiratory flow to expiratory volume,the ratio of PTEF to exhaled time at PTEF(PTEF/TPTEF)were significantly increased,while tidal volume per kilogram(VT/kg),the ratio of exhaled time at PTEF to total expiratory time(TPTEF/TE),tidal expiratory flow at 25% of the remaining tidal volume(TEF25%),the exhaled volume at peak tidal expiratory flow and the index responding to small airway function,such as the ratio of TEF25% to PTEF and the ratio of VPTEF to expiratory volume were significantly decreased as compared with those in healthy infants.But the ratio of mid-expiratory flow to mid-inspiratory flow(ME/MI)which is related to the obstruction site and damage degree of big airway showed no significant difference.The pulmonary function between groups for different pathogen also had no significant difference.Conclusion RSV or MP infection in infant with pneumonia results in impaired pulmonary function,especially for obstruction in small airway.There is no significant difference between RSV and MP pneumonia.Whether subsequent outcomes are different or not needs to be proven by follow-up study.The results suggest that TBFVLs can be used as the important criteria for damage of lung function.So it is well worth application in clinic.