Unilateral renal agenesis and ipsilateral absence of the vas deferens in a cryptorchid infant with Klippel-Feil syndrome.

We report an exceedingly rare case of Klippel-Feil syndrome (KFS), compounded by ipsilateral absence of the vas deferens, renal agenesis, and diaphragmatic hernia. Unilateral absence of the vas deferens was found incidentally during orchidopexy. To the best of our knowledge, no case of unilateral absence of the kidney and vas deferens has been reported in children with KFS.