Subclinical pulmonary involvement in children with juvenile rheumatoid arthritis and systemic lupus erythematosus: Clinical, functional, high-resolution computed tomographic and laboratory findings

ABSTRACT

Early detection of collagen-associated pulmonary disease could have an important effect on prognosis and therapeutic strategies to prevent irreversible pulmonary damage. The aim of this study was to determine the prevalence and characteristics of pulmonary involvement in children with juvenile rheumatoid arthritis [JRA] and systemic lupus erythematosus [SLE] of less than 2-year duration and without prior clinical evidence of lung disease. Twenty-eight patients with JRA [18M and 1OF, mean age 10.3 +/- 2.8 years] and twenty with SLE [6M and 14F, mean age 12.9 +/- 3.1 years] and twenty age- and gender-matched controls were studied. Patients were evaluated using the following measures: clinical, pulmonary function testing [PFT], chest radiography [CXR], high resolution computed tomogram [HRCT], induced sputum cells, phospholipids [PLs] and surfactant protein-A [SP-A] concentrations were also measured in 19 JRA and 12 SLE patients. Results: Measurements of PFT and sputum cellular and biochemical variable were significantly different in study patients as compared to controls. Abnormalities in PFTs, CXR, HRCT and sputum cells and SP-A/PL in JRA were 21.4%, 0.0%, 32.2%, 52.6% and 31.6%, respectively; and in SLE were 30%, 10%, 45%, 54.8% and 33.3%, respectively. Restrictive pattern was the commonest PFT abnormality. PFT results correlated significantly only with age in JRA and with hematological data in SLE. HRCT findings correlated significantly in JRA patients with seropositve disease, high activity grade, and diminished diffusion lung capacity [DLCO], and in SLE with PFTs FVC, FEVI,FEF25-75% and DLco. Neutrophic alveolitis was closely associated with HRCT changes, low DLco and low sputum SP-A values. Pulmonary changes in children with recent onset JRA and SLE are frequent. The significance of these changes is being determined in a longitudinal study