ABSTRACT
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