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RATIONALE Variable disease course and outcomes have been reported in Children's interstitial lung disease (ChILD) associated with Filamin A gene (FLNA) variants. OBJECTIVES To further delineate long term respiratory outcomes and identify potential contributing factors to severe disease course. METHODS We retrospectively collected longitudinal data from 3 centres on 9 cases (1 male) with FLNA variants and early respiratory disease onset (within the first 24 months of life). Clinical, radiographic, and histopathologic data were analyzed, focusing on cardiorespiratory disease course. RESULTS All required early respiratory support (3 invasive ventilation, 3 non-invasive ventilation, 3 supplemental oxygen) and all experienced frequent severe infective respiratory exacerbations. Three died in infancy from refractory respiratory failure and pulmonary hypertension (PH). The 6 surviving individuals were 3, 10, 11, 15, 18, and 33 years old at time of reporting. The extent of functional respiratory impairment decreased with age; at last follow-up there were no individuals on home invasive ventilation, 1 on nocturnal non-invasive ventilation, 4 on oxygen, and 1 on no respiratory support. Spirometry consistently demonstrated moderate to severe obstructive defects (forced expiratory volume over 1 second/ forced vital capacity (FEV1/FVC) Z score -3.76 to -1.77), percent predicted FVC 31.5 to 92.1 %. Seven required PH treatment in early childhood (7/9) and 3 of the survivors (3/6) still receive treatment. Radiologic and histopathologic findings were consistent between cases. CONCLUSION Early mortality was common, but many survivors stabilized even after severe symptoms in infancy. All survivors had persistent obstructive defects on spirometry and half have persistent or recurrent PH. These typical findings are suggestive of this rare diagnosis and should prompt consideration of genetic testing.