Pulmonary function detection in lung injury caused by juvenile systemic lupus erythematosus and juvenile dermatomyositis

Wang Yajun; Lai Jianming; Hou Dongqing; Li Shuo; Song Xin

doi:10.3760/j.issn.1673-4777.2019.07.010

Abstract：Objective To investigate the value of diffusion capacity for carbon monoxide of lung tested by single breath(DLCO-SB) in lung injury caused by juvenile systemic lupus erythematosus and juvenile dermatomyositis.Methods From May 2016 to December 2018,40 cases of juvenile systemic lupus erythematosus and 20 cases of juvenile dermatomyositis were randomly enrolled from Capital Institute of Pediatrics as observation group;63 children with pneumonia matched by age were enrolled as control group.AII children were detected pulmonary ventilation,airway resistance,DLCO-SB and lung high-resolution CT (HRCT).Results of pulmonary function tests,clinical manifestations and HRCT findings were analyzed.Results Among the 60 children in observation group,abnormal rate of DLCO-SB was significantly higher than that of respiratory symptoms and signs [53.3％ (32/60) vs 16.7％ (10/60)] (x2 =17.729,P ＜ 0.001).Twenty-two children showed abnormal lung HRCT results in observation group,including 9 cases of ground-glass opacity,8 cases of small opacity and 7 cases of pleural effusion;abnormal rate of DLCO-SB was significantly higher than that of HRCT [36.7％ (22/60)](x2 =17.045,P ＜0.001).Abnormal rate of DLCO-SB in observation group was significantly higher than that in control group[11.1％ (7/63)] (x2 =25.301,P ＜ 0.001).In observation group,38 children without abnormal HRCT findings had DLCO-SB lower than 80％ of the predicted value;the mean value was (136 ± 29)％;the abnormal rate was 39.5％.Conclusions Juvenile systemic lupus erythematosus and juvenile dermatomyositis can induce interstitial lung disease,which mainly manifests as diffusion capacity reduction and restrictive ventilatory function disturbance.DLCO-SB has a higher sensitivity than HRCT in the diagnosis of interstitial lung disease.Pulmonary function detection shows certain differential diagnostic value for interstitial lung disease and pulmonary infection.