Application of D-dimer in diagnosis and prognosis of childhood Mycoplasma pneumoniae pneumonia / 中华实用儿科临床杂志

ABSTRACT

Objective To analyze the practical value of D-dimer in diseases condition judgment and prognosis evaluation of childhood Mycoplasma pneumoniae pneumonia (MPP).Methods Retrospective analysis was performed on clinical data of 606 MPP at Department of Respiratory,Beijing Children's Hospital,Capital Medical University from January 2009 to July 2017,and the subjects were divided a severe group (298 cases) and a moderate group (308 cases) according to severity.By comparing clinical characteristics,laboratory tests and imaging findings,multivariate Logistic regression analysis for significant single factors was accomplished,which was to find out the independent factors affecting the severity of childhood MPP in acute phase.Receiver operating characteristic (ROC) curves were drawn in the area under the curve (AUC) and the diagnosis threshold value was calculated,which could be used to judge the predicators affecting the severity judgment of childhood MPP in acute phase.And the prognosis was judged according to the convalescent fiberoptic bronchoscopic indicators in recovery phase.Results The levels of white blood cells (WBC) [(10.25 ± 3.76) × 109/L],neutrophil (Neu) [(7.31 ± 3.76) × 109/L],platelet (PLT) [(334.66 ± 143.80) × 109/L],C-reactive protein (CRP) [(69.00 ± 80.50) mg/L],erythrocyte sedimentation (ESR) [(39.38 ± 26.29) mm/1 h],lactate dehydrogenase (LDH) [(436.61 ± 248.96) IU/L],fibrinogen (Fib) [(4.61 ± 1.36) g/L] and D-dimer [(2.09 ± 1.66) mg/L] in the severe group were higher than those in the moderate group [(7.55 ±3.14) × 109/L,(4.77 ±2.54) × 109/L,(291.60 ± 109.19) × 109/L,(23.40 ±42.50) mg/L,(30.25 ± 16.18) mm/1 h,(318.05 ± 116.97) IU/L,(4.18 ±0.88) g,(0.58 ±0.72) mg/L],and the differences were statistically significant (all P ＜ 0.01).The levels of Neu,PLT,CRP,LDH and D-dimer were independent and relevant factors for the severity of acute MPP.The area under each ROC curve was Neu 0.719,PLT 0.592,LDH 0.675,CRP 0.749,D-dimer 0.848,and each diagnostic threshold was 6.5 × 109/L,265.5 × 109/L,417.5 IU/L,28.9 mg/L,0.73 mg/L,respectively.Obviously,D-dimer had the highest sensitivity and specificity for the severe MPP.There was a significant difference in D-dimer level between the endobronchial inflammation group and the subbronchial stenosis,poor ventilation and occlusion group of fiberoptic bronchoscopy [(1.11 ± 0.26) mg/L vs.(2.14 ± 1.84) mg/L,t =-5.870,P ＜ 0.05].Conclusion D-dimer levels can be used as one of the most sensitive indicator for determining the severity and prognosis of MPP.