Nasal potential difference: Best or average result for CFTR function as diagnostic criteria for cystic fibrosis?

Katherine Keenan; Julie Avolio; Claudia Rueckes-Nilges; Elizabeth Tullis; Tanja Gonska; Lutz Naehrlich

doi:10.1016/j.jcf.2014.09.006

Nasal potential difference: Best or average result for CFTR function as diagnostic criteria for cystic fibrosis?

J Cyst Fibros. 2015 May;14(3):310-6. doi: 10.1016/j.jcf.2014.09.006. Epub 2014 Oct 7.

Authors

Katherine Keenan¹, Julie Avolio², Claudia Rueckes-Nilges³, Elizabeth Tullis⁴, Tanja Gonska⁵, Lutz Naehrlich⁶

Affiliations

¹ Division of Paediatric Gastroenterology, Hepatology and Nutrition, University of Toronto and Physiology and Experimental Medicine, Research Institute, the Hospital for Sick Children, Toronto, Ontario, Canada. Electronic address: [email protected].
² Division of Paediatric Gastroenterology, Hepatology and Nutrition, University of Toronto and Physiology and Experimental Medicine, Research Institute, the Hospital for Sick Children, Toronto, Ontario, Canada. Electronic address: [email protected].
³ Department of Pediatrics, Justus-Liebig-University Giessen, Giessen, Germany. Electronic address: [email protected].
⁴ Department of Medicine, University of Toronto and Division of Respirology and Keenan Research Centre of Li Ka Shing Knowledge Institute St. Michael's Hospital, Toronto, Ontario, Canada. Electronic address: [email protected].
⁵ Division of Paediatric Gastroenterology, Hepatology and Nutrition, University of Toronto and Physiology and Experimental Medicine, Research Institute, the Hospital for Sick Children, Toronto, Ontario, Canada. Electronic address: [email protected].
⁶ Department of Pediatrics, Justus-Liebig-University Giessen, Giessen, Germany. Electronic address: [email protected].

PMID: 25300456
DOI: 10.1016/j.jcf.2014.09.006

Abstract

Background: The current practice of averaging the nasal potential difference (NPD) results of right and left nostril measurements reduce inter-individual variability but may underestimate individual CFTR function.

Methods: Best NPD response to Cl(-)-free and isoproterenol perfusion (=largest ΔPD(0Cl/Iso)) from the right and left nostril was compared to the average result in 13 cystic fibrosis (CF), 78 query-CF patients and 22 healthy controls from 2 cohorts.

Results: Despite moderate to good correlation (p<0.001) between right and left measured ΔPD(0Cl/Iso), we observed large differences in some individuals. A comparison of average versus best ΔPD(0Cl/Iso) showed only moderate agreement (Giessen κ=0.538; Toronto κ=0.607). Averaging ΔPD(0Cl/Iso) showed a lower composite chloride response compared to best ΔPD(0Cl/Iso) and altered diagnostic NPD interpretation in 30 of 113 (27%) subjects.

Conclusions: The current practice of averaging the NPD results of right and left nostril measurements leads to an underestimation of the individual CFTR function and should be reconsidered.

Keywords: Cystic fibrosis; Diagnosis; Nasal potential difference.

Publication types

Multicenter Study

MeSH terms

Adult
Biomarkers / metabolism
Cystic Fibrosis / diagnosis*
Cystic Fibrosis / metabolism
Cystic Fibrosis Transmembrane Conductance Regulator / physiology*
Female
Humans
Male
Nasal Mucosa / metabolism*
Phenotype
Reproducibility of Results
Young Adult

Substances

Biomarkers
Cystic Fibrosis Transmembrane Conductance Regulator