Oman Medical Journal (Jan 2012)
Extent of Subclinical Pulmonary Involvement in Childhood Onset SystemicLupus Erythematosus in the Sultanate of Oman
Abstract
Objectives: The aim of this study was to investigate the frequencyof pulmonary function abnormalities in clinically asymptomaticchildren with Systemic Lupus Erythematosus and to determinethe relationship of these abnormalities to clinical, laboratory, andimmunological parameters as well as to disease activity.Methods: Forty-two children with childhood onset SystemicLupus Erythematosus were included in this study. Demographic,clinical, laboratory and immunological parameters, as well asdisease activity were assessed. Pulmonary function tests (PFT)were performed routinely to screen for subclinical lung disease.Results: Out of the 42 children, 19�0(n=8) had clinical evidence ofpulmonary involvement. The patients with no clinical evidence ofpulmonary involvement (n=34) represent the study cohort. Fromour cohort of patients with no clinical evidence of pulmonaryinvolvement 79�0(n=27) had PFT abnormality; including 62�=21) had reduced FVC, 71�0(n=24) had reduced FEV1, and67�0(n=12) had reduced DLCO. Similarly, 56�0(n=15) hada restrictive PFT pattern, and 2.6�0(n=2) had an obstructivePFT pattern, while 33�0(n=7) had an isolated impairment ofdiffusion capacity. Due to small sample size; it was not possibleto find a statistically significant difference between the cohort ofasymptomatic SLE patients with abnormal PFT findings (n=27)and those with normal PFT findings (n=7) in terms of clinical,laboratory, immunological or disease activity index score.Conclusion: Subclinical lung disease, as demonstrated byabnormal PFT in patients with normal radiographs, may becommon but should be interpreted with caution as an early signof lung disease. Although PFT studies do not correlate well withpulmonary symptoms in patients with childhood onset SLE,they nevertheless provide objective quantification of the type andseverity of the functional lesions.
