Assessment of the severity of chronic sinusitis in children with cystic fibrosis using the Lund-Mackay Score depending on genotype

Abstract

Introduction. Chronic sinusitis affects most patients with cystic fibrosis (CF). The Lund-Mackay (LM) scale is an objective tool allowing for easy assessment of the severity of lesions in sinuses observed in computed tomography (CT). The link between clinical picture, image results and CFTR gene mutations is not well evaluated. Aim. To specify the correlation of the severity of lesions found in computed tomography and the CFTR gene mutation type causing an underlying disease in children with cystic fibrosis. Material and methods. Data of the children with cystic fibrosis who underwent CT between 2016-2018 at the Department of Paediatric Otolaryngology of the Medical University of Warsaw was analysed. The following factors were taken into account: age, sex and CFTR gene mutation type. Each CT was assessed using the basic and modified Lund-Mackay Score (LMS and MLMS). The study was retrospective. Results. 34 children, 16 girls and 18 boys aged between 3 and 17 years (median age ? 10 years), were enrolled to the study at the time of CT. LMS median was 17 (range 2-23), and MLMS ? 18 (range 2-24), and their difference was statistically significant. 16 patients were F508del homozygous. Severe CFTR mutation in both alleles was observed in 28 patients, and mild mutation was found in at least one allele in 6 patients. LMS median in the group of patients with severe mutation was 17.5, and in the group of patients with mild mutation ? 14.5. MLMS median was 18 and 14.5, respectively. The difference was statistically significant for both LMS and MLMS. No statistically significant correlation was found between the LMS and MLMS results and sex. The weak positive correlation between LMS and MLMS and patient’s age was not statistically significant. Hypoplasia or aplasia of one or more paranasal sinuses was observed in 11 children (32%). Conclusions. The score on the modified Lund-Mackay scale is higher than the score on the basic LMS scale in children with cystic fibrosis. The group of patients with a severe CFTR gene mutation has higher scores for both LMS and MLMS than the group with a mild mutation. Due to frequent sinus aplasia in children with cystic fibrosis, the use of the modified Lund-Mackay scale allows for error avoidance when comparing CT results of different patients.