Congenital bilateral absence of the vas deferens: clinical characteristics, biological parameters, cystic fibrosis transmembrane conductance regulator gene mutations, and implications for genetic counseling.

OBJECTIVE

To evaluate relationships between the phenotypic and genotypic characteristics of patients with congenital bilateral absence of the vas deferens (CBAVD).

DESIGN

Retrospective study.

SETTING

A university hospital urology-andrology department.

PATIENT(S): Forty-one men with CBAVD.

INTERVENTION(S): CBAVD was diagnosed during surgical and/or ultrasound exploration of the vasa deferentia (VD) (n = 39), or on the basis of impalpable scrotal VD (n = 2).

MAIN OUTCOME MEASURE(S): History, clinical and seminal characteristics, and cystic fibrosis transmembrane conductance regulator (CFTR) gene mutations including IVS-8 polyT analysis.

RESULT(S): A palpable scrotal vas deferens was present as a fibrous cord or nonpermeable duct in 13% of patients undergoing surgical exploration. Seminal vesicles were bilaterally absent in 28% of patients. No CFTR gene mutation or 5T allele was detected in 24.5% of the patients. Two CBAVD patients with renal agenesis carried a CFTR gene mutation (DeltaF508/5T-9T and R117G/7T-9T). CBAVD patients who have both a semen volume of < or =1.0 mL and a semen pH of < 7.0 have a significantly higher risk of severe CFTR gene mutation (OR = 9.12 [95% CI = 1.81-49.50]).

CONCLUSION(S): A palpable scrotal vas deferens was found in 13% of CBAVD patients. Semen volume of < or =1.0 mL and semen pH of < 7.0 in CBAVD patients were associated with a higher risk of severe CFTR gene mutations. Patients with CBAVD and renal agenesis should be screened for CFTR gene mutations before assisted reproductive techniques are used.