Calcium creatinine ratio on spot urine sample is a good screening test for hypercalciuria. A ratio of >0.8 mg/mg in children below 6 months , >0.6 mg/mg in children 6-12 months and > 0.2 mg/mg in older children is abnormal. Testing should be done on at least two spot samples on different occasions. We try to confirm it on a 24 hr urine sample. Calcium excretion > 4 mg/kg/day is abnormal. Hypercalciuria in a child is an important cause of hematuria.
Evaluation & managing a child with hypercalciuria
Idiopathic hypercalciuria is a diagnosis of exclusion. A child with hypercalciuria needs referral to a Pediatric Nephrologist for detailed evaluation for underlying etiology like renal tubular disorders, parathyroid disorders and other endocrine disorders etc. Pending evaluation general measures like increased fluid intake , low salt diet and alkali therapy under the supervision of pediatric nephrologist can be started. There is no need for calcium restriction.