Recurrent abdominal and flank pain in children with idiopathic hypercalciuria.

OBJECTIVE: To evaluate the role of idiopathic hypercalciuria (IH) as a cause of recurrent abdominal pain (RAP) in children.

PATIENTS AND METHODS: We retrospectively reviewed the medical records of 124 children referred for various complaints who had 24-h urine calcium excretion greater than 2 mg/kg/d or random urine calcium-creatinine ratio greater than 0.18 mg/mg.

RESULTS: Fifty-two children with various clinical complaints had RAP or flank pain. These comprised of 22 males and 30 females, 9 mo to 15.9 y of age, mean 6.7 +/- 3.5 y. A family history of urolithiasis was present in 50% of all the children. Only 6 of the 52 children with abdominal pain had renal stones. In addition to abdominal pain, 27 children had hematuria and 10 had urinary incontinence. Mild metabolic acidosis was present in three children, parathyroid hormone activity elevated in two and serum vitamin D activity was increased in nine. All children were treated with increased fluid intake and a reduction in dietary sodium and oxalate and some required treatment with thiazide and antispasmodics. Forty-five cases responded to treatment, 5 failed to improve from therapy, and 2, which were not followed up as patients, were not available.

CONCLUSION: We describe 52 children with RAP or back pain due to IH and recommend that IH be considered in the differential diagnosis of RAP in childhood.