Abstract: Objective To analyze the clinical characteristics of refractory Mycoplasma pneumoniae pneumonia(RMPP),in different effect response to treatment by observing the 3 5d effects in the initial treatment with conventional dose of methylprednisolone Methods Retrospective analysis was performed on the clinical data of 127 cases of RMPP patients treated in Dalian Municipal Women and Children′s Medical Center from January 2015 to December 2018 According to initial 3 5d effects of 2 mg/(kg·d) methylprednisolone,the dose was further adjusted,and patients were divided into 3 groups,“conventional” group,“high dose” group and “long course” group The clinical features,radiological features,laboratory examination and prognosis of the cases were compared Results （1）The rates of respiratory failure,extrapulmonary complications,cloudy opacity,lobar lung consolidation and necrotizing pneumonia in the three groups were statistically different(P<0.05);the incidence of extrapulmonary complications in “high dose” group was higher than the other two groups(P<0.017),and severe extrapulmonary manifestations were predominant in “high dose” group(26/31),but extrapulmonary manifestations of the other two groups were mainly mild(6/9,41/55) There was no significant difference in rates of wheezing,allergic diseases,family allergic diseases,mixed infection,diffused interstitial changes,acute pulmonary effusion,atelectasis among the three groups(P>0.05)（2）The levels of lactic dehydrogenase and serum ferritin in the three groups were statistically different(P<0.01),and they were higher in the “high dose” group than in the other two groups(P<0.01) The level of fibrinogen in the three groups was statistically different(P<0.05),and it was higher in the “high dose” group than in “conventional” group(P<0.05) Comparing the Ceactive protein of the three groups,the level of C reactive protein in “high dose” group was higher than that in “conventional” group(P<0.05)There was no significant difference in levels of white blood cell count,percentage of neutrophils,eosinophil count,creatine kinase isoenzyme or D Dimer among the three groups(P>0.05) （3）In 6 months of follow up after treatment,the rates of lung consolidation and interstitial changes in the three groups were statistically different(P<0.05),and they were higher in the “high dose” group than in the “conventional” group(P<0.017) There were no significant differences in rates of atelectasis or wheezing among the three groups in the 6 month follow up (P>0.05) Conclusion Conventional dose of methylprednisolone may be ineffective in RMPP cases with respiratory failure,severe extrapulmonary complications,lobar lung consolidation,and necrotizing pneumonia significant increase of lactic dehydrogenase,serum ferritin,fibrinogen and C reactive protein,and these cases may have high risk of lung sequelae  It is recommended to give high dose methylprednisolone,immunoglobulin,anticoagulation combined with bronchoscopic treatment,and to make regular re examination.

Key words: Refractory Mycoplasma pneumoniae pneumonia, Methylprednisolone, Curative effect, Child