[Clinical characteristics of juvenile dermatomyositis complicated with interstitial lung disease]

To explore the clinical and laboratory features and the prognosis of juvenile dermatomyositis (JDM) complicated with interstitial lung disease (ILD).

Data of 39 cases of JDM complicated with ILD hospitalized in Beijing Children's Hospital from January 2005 to December 2011 were collected. The clinical features, laboratory data and prognosis of these children were analyzed.

Of the 39 cases studied, 16 were boys, and 23 girls. The average age of onset was 5.6 years, and 61.5% of the patients' age of onset (24 cases) was under 6 years. Rashes (17 cases, 43.6%), simultaneous eruption of rashes and muscle weakness (14 cases, 35.9%), fever (4 cases, 10.1%), or muscle weakness (3 cases, 7.7%) were common initial symptoms of the disease. Only 51.3% of the patients (20 cases) had the symptoms of respiratory system, but (24 cases) 61.5% were complicated with that of the gastrointestinal system; (27 cases) 69.2% had at the same time electrocardiographic and echocardiographic abnormalities. The chest high resolution computed tomography (HRCT) showed cord or band-like shadows in their lungs of more than half of the cases (25 cases, 64.1%), and other changes included ground glass-like shadow (10 cases, 25.6%), net and lineation-like shadow (9 cases, 23.1%), nodular change (5 cases, 12.8%). The patients complicated with lung essential infiltration accounted for as high as 71.8% (28 cases). These imaging changes were largely seen on both dorsal sides of their lungs. Severe patients also had mediastinal emphysema, pneumothorax, pneumorrhagia or aerodermectasia. Twenty-four patients underwent pulmonary function examination, and 62.5% of the patients' pulmonary function (15 cases) was abnormal. The fatality rate of the cases studied was 10.1%.

The imaging changes of patients suffering from JDM with ILD were often more severe as compared to the clinical symptoms, and were often complicated with damages to other systems and organs. The prognosis of those patients was poorer than others. Patients with JDM especially at a younger age of onset and with various organ damages should be examined with chest HRCT examinations as early as possible.