Pulmonary outcome in juvenile dermatomyositis: a case-control study

Area of Science:

• Rheumatology
• Pulmonology
• Pediatric Autoimmune Diseases

Background:

• Juvenile dermatomyositis (JDM) is a rare autoimmune disease affecting children.
• Pulmonary involvement in JDM can be a significant complication, impacting long-term health outcomes.

Purpose of the Study:

• To compare pulmonary function in JDM patients with matched controls.
• To investigate the association between pulmonary function impairment, high-resolution CT (HRCT) findings, and other disease variables in JDM.

Main Methods:

• Compared 59 JDM patients (median 16.8 years post-onset) with 59 age- and sex-matched controls.
• Utilized spirometry, diffusing capacity for carbon monoxide (DLCO), and body plethysmography for pulmonary function tests.
• Performed HRCT scans and assessed cumulative organ damage and patient-reported health status in JDM patients.

Main Results:

• JDM patients exhibited significantly lower total lung capacity (TLC) and DLCO compared to controls.
• Abnormal HRCT findings, including interstitial lung disease (ILD), chest wall calcinosis, and airway disease, were present in 37% of JDM patients.
• Low TLC was more frequent in JDM patients with abnormal HRCT, and HRCT abnormalities correlated with cumulative organ damage and patient-reported health status.

Conclusions:

• JDM patients demonstrate reduced lung volumes and a higher prevalence of restrictive ventilatory defects and HRCT abnormalities.
• The association between pulmonary function deficits and HRCT findings underscores the systemic nature of JDM.
• Pulmonary involvement in JDM, often subclinical, necessitates careful monitoring due to its frequency and association with disease burden.