Urinary incontinence due to idiopathic hypercalciuria in children.

Idiopathic hypercalciuria is known to cause many nonstone urinary tract disorders in childhood. In addition to being the most common cause of microhematuria in children, our study demonstrates that idiopathic hypercalciuria is also frequently associated with urinary incontinence of all types. Of 124 children evaluated for idiopathic hypercalciuria 28 (23%) had urinary incontinence. Of the 28 children 15 (54%) had nocturnal, 6 (21%) diurnal, and 7 (25%) nocturnal and diurnal incontinence. The random urinary calcium-creatinine ratio, which was used to screen for hypercalciuria, should be part of the initial evaluation for urinary incontinence in children. Diagnosis may be confirmed by quantitative urinary calcium excretion. Most urinary incontinence in children that is due to idiopathic hypercalciuria responds to a combination of general treatment for hypercalciuria or thiazide diuretics.