Hypospadias and urethral abnormalities in Down syndrome.

In the course of general medical evaluations of 149 children and adolescents (younger than 21 years of age) and 11 adults with Down syndrome, five of the 77 males were noted to have dorsal urethral duplications. In all instances, there proved to be a single urethral meatus. The second opening led into a pit or blind channel, reflecting the presence of a distal hypospadias. In these five patients, laboratory studies were normal, nephrology histories were negative, and radiographic studies did not demonstrate any anatomic abnormalities of the urethra, ureters, or kidneys. These findings indicate that there is an increased occurrence of distal hypospadias in males with Down syndrome that may present with dorsal urethral duplications and/or glanular hypospadias.