Lower Urinary Tract Morphology in Patients with Hypospadias

Hypospadias is a relatively common anomaly of the lower urinary tract seen in 8 children per 1000 male births (Sweet et al., 1974). Developmental arrest during fetal organogenesis produces a fusion defect in the urethral tube. The fusion of the urethral folds is induced by fetal testicular androgen, therefore the occurrence of hypospadias is caused by incomplete masculinization of this target structure. This may be a result of either a decline in stimulation caused by diminution in circulating hormones, partial tissue insensitivity or improper chronologic correlation between the hormonal level and the critical time for this tissue to respond to androgens (Horton and Devine, 1972). In the great majority of cases, hypospadias occurs as a single defect with no apparent or demonstrable genetic or endocrine disturbance at birth or later in life (Aarskog, 1970). However, it may also be a manifestation of more permanent genetic and endocrine derangements, especially if there is ambiguity of external genitalia or the presence of another disorder of male sexual differentiation such as cryptorchidism or well-developed Mullerian duct structures.