[Andrological description of a population of azoospermic men with agenesis of the vas deferens]

Abstract

Context: In the 1990's, congenital agenesis of the vas deferens was identified as a minor form of cystic fibrosis in relation to the frequency of mutations of the CFTR gene associated. It is responsible for masculine infertility by obstructive azoospermia; which is not accessible to a surgical treatment. However, surgical sperm retrieval and injection de spermatozoïde en intracytopasmique (ICSI) allow fatherhood for these patients.

Patients and methods: A retrospective analysis of 104 consecutive patients from 1996 to 2006. A comprehensive clinical, spermiologic, hormonal, imaging and genetic workup was carried on. The data from the surgical extractions and the attempts of ICSI were collected.

Results: Seventy-five percent of the patients had a mutation of the CFTR gene; ultrasound imaging revealed a renal or a seminal vesicle abnormality in 20% and 84.5% of the patients, respectively. The association of a semen volume less than 2 mL with a pH less than 7.2, a fructose less than 2 and mean sudoral chlore greater than 60 mmol/L enabled an immediate identification of 30% of patients carrier of the mutation and without renal abnormality. The sperm extraction rate was 98%.

Conclusion: A search for the CFTR gene mutations and an ultrasound imaging of the genito-urinary system are essential to the workup of these patients. The association of a semen volume less than 2 mL, a semen pH less than 7.2 and a fructose less than 2 must point towards a minor form of cystic fibrosis and prompt the workup of genetic abnormalities and sudoral chlore testing. The results of the sperm extraction combined to the technical advances of IVF/ICSI allow excellent pregnancy rates of 66% for the companions of these patients.

Keywords: Agenesis of the vas deferens; Agénésie des déférents; Azoospermia; Azoospermie; CFTR gene; Gène CFTR; ICSI; Prélèvement chirurgical de sperme; Testicular sperm extraction.