Transient ureteric dilatation in neonates with imperforate anus: a report of 4 cases.

In a series of 64 patients with imperforate anus, 4 were identified with ureteric dilatation without vesico-ureteric reflux. The appearance resembled that of the primary obstructive megaureter. However, since the dilation resolved spontaneously in each case, it is concluded that the condition represents a separate entity, the cause of which has not yet been elucidated.