Bed wetting can affect sleep patterns and often it causes frustration and exhaustion. Adult Onset Secondary Enuresis is defined as nocturnal enuresis in which. Bed-wetting that starts in adulthood (secondary enuresis) is uncommon and requires medical evaluation. Causes of adult bed-wetting may include: A blockage (obstruction) in part of the urinary tract, such as from a bladder stone or kidney stone. Bladder problems, such as small capacity or overactive nerves.