Clinical features and pulmonary function in children with Swyer-James-Macleod syndrome: A single center experience

Abstract

Purpose: Swyer-James-Macleod syndrome (SJMS) is a rare disorder characterized by the hyperlucency of a unilateral lung due to ip silaterally arrested lung growth. No sufficient information on progressive lung function changes during growth is available in SJMS. Methods: We retrospectively reviewed SJMS cases using a clinical database from January 2000 to August 2018. Results: A total of 40 patients were enrolled in this study. The median age of the patients was 4.8 years (interquartile range [IQR], 2.7-9.0 years), boys (n=21, 52.5%) were more affected, and left lungs (n=27, 67.5%) were more involved. The interval between in fection and diagnosis was 1.8 years (IQR, 0.7-6.4 years). Mycoplasma pneumoniae (n=14) and adenovirus (n=5) were most preva lent among the 21 subjects with presumably identifiable causes. Most of the 16 patients with available pulmonary function data presented moderate obstructive lung function (z-score, median; FEV1: -4.320 [IQR, -5.955 to -3.400] and FVC: -2.600 [IQR, -3.590 to -1.570], respectively) with the more decreased median in forced expiratory flow between 25% and 75% of FVC (FEF25%-75%) (z-score, -4.470; IQR, -5.330 to -3.170). Linear mixed effect models indicated that younger age at first infectious insult was significantly related to decreased FEV1 z-score (P=0.041), and that the FEV1/FVC and FEF25%-75% z-scores were reduced by 0.082 (P=0.005) and 0.069 (P≤0.001) per year. Conclusion: In children with SJMS, the initial infectious insult occurs in the early life with M. pneumoniae being the most common pathogen. Lung function may deteriorate with an obstructive pattern during growth. The impairment can progress slowly not in the FEV1, but in the FEV1/FVC or FEF25%-75%. (Allergy Asthma Respir Dis 2021;9:156-163)