Background Sarcoidosis is a rare lung disease in children. The aim of the present study was to provide update information on disease presentation and progression, patient management and prognosis factors in a cohort of children with lung sarcoidosis.

Methods With the network of the French Reference Centre for Rare Lung Diseases (RespiRare), we collected information on a large cohort of paediatric thoracic sarcoidosis to provide information on disease presentation, management and outcome.

Results Forty-one patients were included with a median age at diagnosis of 11.8 years (1.1–15.8), mostly from Afro-Caribbean and Sub-Saharan origin. At diagnosis, 85% presented with a multi-organic disease, and no major differences were found regarding disease severity between the patients diagnosed before or after 10 years old. Corticosteroids were the most used treatment, with more intravenous pulses in the youngest patients. The 18-month outcome showed that patients diagnosed before 10 years old were more likely to recover (50% vs 29%), and presented fewer relapses (29% vs 58%). At 4–5 years of follow-up, relapses were mostly observed for patients diagnosed after 10 years old.

Discussion In the included children, mostly of Afro-Caribbean and Sub-Saharan origin, sarcoidosis seems severe, with multi-organic involvement and foreground general symptoms. Common prognosis factors are not suitable in paediatric patients, and a young age at diagnosis does not seem to be associated with a poorer prognosis. The study is ongoing to provide further information on the very-long-term follow-up of paediatric sarcoidosis.