小儿肺炎支原体感染诊断及发病机制探讨

The study of diagnosis and pathogenesis of mycoplasma pneumonia infection in children

探讨小儿肺炎支原体（Ｍｐ）感染的敏感诊断方法与发病机制。方法采用聚合酶链反应（ＰＣＲ）技术检测咽拭子Ｍｐ－ＤＮＡ，同时做血清冷凝集试验（ＣＡＴ），对４９８例呼吸道感染的住院患儿进行配对资料研究，４８例测定了有关免疫指标。结果ＰＣＲ法阳性率为３７．５５％（１８７／４９８），ＣＡＴ法阳性率为１０．０４％（５０／４９８），二法差异有极显著性意义。３～１０岁组感染率明显高于３岁以下组与１０岁以上组。ＰＣＲ法不受自然病程的影响，ＣＡＴ法明显受到病程的影响。１２例Ｍｐ－ＤＮＡ－ＰＣＲ和循环免疫复合物（ＣＩＣ）均阳性者多伴有肺外并发症。结论ＰＣＲ法是早期诊断Ｍｐ感染的敏感方法，明显优于ＣＡＴ法。

Objective The purpose of this study was to explore a sensitive diagnostic method and pathogenesis of mycoplasma pneumonia infection in childhood.Methods Mycoplasma pneumonia(Mp)DNAs were determined by polymerase chain reaction(PCR) from nasopharyngeal swabs of 498 children with respiratory tract infection whose serum samples were collected on the same day for cold agglutination test (CAT),and some immunological values were determined in 48 of them.Results The positive rate of Mp-PCR was found to be 37.55%,whereas that of serum CAT 10.04%(P<0.001).The result of Mp-PCR was not related to the natural course of the respiratory tract infection,but the value of the serum CAT was associated with it.Respiratory and extrapulmonary manifestations have been detected in 12 of the children with positive values of Mp-PCR-DNA and circulating immune complex (CIC).Conclusion The Mp-PCR is a more sensitive method than serum CAT for early diagnosis of mycoplasma pneumonia infection.Mycoplasma pneumonia infection in children may be related to allergy (immune complex type).