Response of Enuretic Children with and without Hypercalciuria to Nasal Desmopressin

Nocturnal enuresis is a common diagnosis in patients referred to pediatric and pediatric nephrology clinics. Nocturnal polyuria is an important patho-physiologic factor in enuresis. Hypercalciuria, with altering concentrating capacity of the kidneys, can affect children''s response to desmopressin. This is a double blind clinical trial starting September 2007 to March 2008. One hundred and twenty four enuretic children, 76 (61.3%) males, 48 (38.7%) females, mean age 7.7 (±1.7), were evaluated by measuring random morning urinary calcium to creatinine ratio. Patients were divided into group 1 with a calcium to creatinine ratio equal to or more than 0.2 mg/mg, and group 2 with a ratio less than 0.2 (Hypercalciuric and non hypercalciuric respectively). All patients received 10 to 40 mcg of nasal desmopressin at bed time. The response was defined as reduction in wet nights, a "full response" (greater than 90 % reduction), "partial response" (50% to 90% reduction) and "no response" (less than 50% reduction). Chi-square method was used to compare the responses and P<0.05 was considered statistically significant. Nineteen patients in group 1 (Hypercalciuric) and 105 patients in group 2 (Non hypercalciuric) were studied. Response to desmopressin was "full" in 47.4% in group 1 and 64.8% in group 2. 42.1% and 26.7% had "Partial response" in group1 and 2 respectively (P<0.04). Hypercalciuria can affect negatively the responsiveness to desmopressin therapy