Dear Editor,

We read with interest Mulla's et al endgame "A man with blocked nose", but in our opinion some clarifications are needed.

The Authors suggest considering "allergic disease, aspirin intolerance, airways diseases, such as bronchiectasis, asthma, and chronic obstructive pulmonary disease" in the differential diagnosis of nasal polyps (NP). However, lower airways involvement is a main feature of both primary ciliary dyskinesia (1) and cystic fibrosis (2), with the latter being more frequent in general population.

Moreover generically suggesting "mucociliary clearance testing" as specialist tests to be performed in patients with NP, may lead to some misunderstanding. In particular NP could be a manifestation of classical cystic fibrosis or be part of the so called CFTR-related disorders. In particular when NP is part of CFTR-related disorders they could be associated to disseminated bronchiectasis or to congenital bilateral absence of the vas deferens (CBAVD) without any other signs of classical cystic fibrosis. Hence, given the fact that recent literature data showed an increased prevalence of heterozygous mutation in patients with NP compared to general population (3-4), we believe that CFTR molecular test is needed in NP population.

1. Rimmer J. Congenital problems of mucociliary clearance: primary ciliary dyskinesia.Rhinology. 2012 Dec;50(4):353-9.
2. Bombieri C, Claustres M, De Boeck K. Recommendations for the classification of diseases as CFTR-related disorders. J Cyst Fibros. 2011 Jun;10 Suppl 2:S86-102.
3. Feuillet-Fieux MN, Lenoir G. Nasal polyposis and cystic fibrosis(CF): review of the literature. Rhinology. 2011 Aug;49(3):347-55
4. Fokkens WJ,et al. European Position Paper on Rhinosinusitis and Nasal Polyps 2012. Rhinol Suppl. 2012 Mar;(23):3 p preceding table of contents, 1-298.

Competing interests: None declared