Cystic fibrosis and Young's syndrome

Abstract

Diana Wellesley and Martin Schwarz1Wellesley D Schwarz M Cystic fibrosis, Young's Syndrome and normal sweat chloride.Lancet. 1998; 352: 38Summary Full Text Full Text PDF PubMed Scopus (4) Google Scholar suggest that in some cases Young's syndrome might be a mild form of cystic fibrosis, and that more extensive gene mutation analysis might clarify the true nature of the diagnosis in men with azoospermia and chronic respiratory disorders. The sweat electrolyte figures were not cited, yet even in adults, borderline or upper range of normal sweat chloride would raise the suspicion of disease mediated by the cystic fibrosis transmembrane conductance regulator protein (CFTR). Measurement of transepithelial nasal potential difference (NPD) has further clarified the relation between Young's syndrome and cystic fibrosis. Men with Young's syndrome have no abnormality of electrolyte transport on NPD measurements, whereas men with cystic fibrosis have reduced chloride transport.2Alton EWFW Currie D Logan-Sinclair R Warner JO Hodson ME Geddes DM Nasal potential difference: a clinical diagnostic test for cystic fibrosis.Eur Resp J. 1990; 3: 922-926PubMed Google Scholar Furthermore, men with isolated congenital absence of the vas deferens, 80% of whom have at least one CFTR mutation,3Costes B Girdon E Ghanem N et al.Frequent occurrence of the CFTR intron 8 (TG)n 5T allele in men with congenital absence of the vas deferens.Eur J Hum Genet. 1995; 3: 285-293Crossref PubMed Scopus (138) Google Scholar have epithelial chloride transport mid-way between cystic fibrosis patients and healthy people.4Osborne LR Lynch M Middleton P et al.Nasal epithelial ion transport and genetic analysis of infertile men with congenital bilateral of the vas deferens.Hum Mol Genet. 1993; 2: 1605-1609Crossref PubMed Scopus (75) Google Scholar The investigators are right to consider cystic fibrosis as a cause of azoospermia and chronic respiratory disease, and although gene mutation analysis may reveal CFTR mutations as the cause in some patients, Young's syndrome seems to be a separate entity and can be distinguished by NPD measurement. Cystic fibrosis and Young's syndromeAuthors' Reply Full-Text PDF