Comparison of olfactory and gustatory function in children and adolescents with Cystic Fibrosis and Primary Ciliary Dyskinesia with healthies

<bold>Background:</bold> Olfactory disorders are a frequent problem in people with Cystic Fibrosis (pwCF) and Primary Ciliary Dyskinesia (pwPCD). But olfactory-independent taste function has rarely been tested or quantified using validated methods in in children and adolescents with CF and PCD. <bold>Methods:</bold> Recruitment is still ongoing. To date, we enrolled 24 pwCF (age 18.0 ± 8.7 years, 50% female) and 18 pwPCD (age 23.6 ± 15.1 years, 61% female). Healthy children served as controls (HC) for the taste (18 children) and odour test (196 children). Apart questions on subjective gustatory and olfactory impairment, current medication, respiratory and ENT symptoms, loss of odour and taste were assessed by validated tests (U-Sniff-Test® (score 0-12; cut-off ≤10 points; severe< 8); Odofin® Taste-Strips (score 0-16 points; cut-off <9)). <bold>Results:</bold> Both general and severe hyposmia are more frequent in each disease group than in HC (CF vs. PCD vs. HC: 54% vs. 57% vs. 35%; severe: 4% vs. 29% vs. 3%). In contrast, hypogeusia was only detectable in pwCF (35 %). Moderate hypogeusia (deviation of more than one standard deviation from the mean score in HC (12.44 ± 2.31)) occur in 30% of pwCF and 6% of pwPCD. For pwCF 'salty' and 'sweet' and for pwPCD 'sour' were difficult to identify. All patients with severe hyposmia had an history of ENT surgery. <bold>Conclusion:</bold> Olfactory dysfunction is equally common in pwCF and pwPCD, whereas taste disorders occur in pwCF. There are also differences in detecting different flavours in PCD and CF. Chemosensory deficits in pwCF and pwPCD are clinically relevant and require further studies to understand pathophysiology and causes.