Prevalence and characteristics of cystic lung lesions in children with interstitial lung diseases – a register-based study

Abstract

<b>Introduction:</b> Cystic lung diseases is a heterogenous group of disorders characterized by the presence of air filled spaces within the pulmonary parenchyma. A large proportion of cystic lesions in children is associated with interstitial lung diseases (ILD). <b>Aim:</b> The aim of this study was to evaluate the prevalence and characteristic of cystic lesions in children with ILD. <b>Methods:</b> An international peer reviewed register (ChILD-EU) was used to select thorax CT scans with cystic lesions (cysts, honeycombing, paraseptal emphysema, bullae). All scans were reviewed by two independent observers. Radiographic findings were classified based on Fleischner Society glossary of terms for thoracic imaging and analyzed in relation to clinical data. <b>Results:</b> 130 out of 812 patients met the inclusion criteria. Due to low quality of CT scans or insufficient data 98 cases could be included in final analysis. Patients with cystic lesions on HRCT represented 28 different clinical diagnoses. The most common were: surfactant protein deficiencies - 26%, bronchiolitis obliterans - 8%, trisomy of 21st chromosome - 6%, filamin A mutation - 5% and Langerhans cell histiocytosis – 5%. Cystic lesions were found in 27.4%, 25.8%, 50%, 55.5% and 100% of children with the above diagnoses, respectively. Paraseptal emphysema, found in 80% of patients, was the most common radiological abnormality, followed by cysts in 26%, honeycombing in 23%, microcysts in 19% and bullae in 18% HRCT scans. Interobserver agreement was 74%. <b>Conclusions:</b> Cystic lesions can be found in children with different ILD. Their prevalence is highly variable but 5 specific diseases are responsible for 50% of these lesions.