Predictive Factors for Complete Response to Desmopressin Treatment in Children With Primary Monosymptomatic Nocturnal Enuresis.

Abstract

Objectives: Primary monosymptomatic nocturnal enuresis (MNE) is a common problem in pediatric urology and desmopressin is the first-line medical treatment. We aimed to evaluate the predictive factors of complete response to desmopressin and the effect of desmopressin on urinary electrolyte levels in children with primary MNE.

Methods: Children with MNE who were started on sublingual 120 mcg of desmopressin treatment included in the study. Children were evaluated by physical examination, urinalysis, voiding dysfunction symptom score, voiding diary and uroflowmetrics with postvoid residuals. 24-h urine was collected for density and electrolyte measurements before and at the first and third months of treatment. The children were divided into two groups according to wetting episodes at the third month, as those with complete response to the treatment (group 1) and the others (resistant or partial-response) (group 2).

Results: Thirty-four children (24 boys, 10 girls) were included in the study. Median age was 8 (5-15) years. There was no difference between the urinary density, sodium, potassium, and calcium values before and during treatment (first and third months) (p = 0.737, 0.549, 0.166, 0.386 respectively). The number of wet nights in a month and the number of wetting at a night were found as the predictive factors for complete response to desmopressin (p = 0.027, p = 0.003, respectively). The number of 17 wet nights per month was calculated as the optimized cut-off point for predicting desmopressin treatment failure (p = 0.027, sensitivity = 92.3%, specificity = 47.6%, AUC [95%]: 0.729 [0.552-0.906]). Age, gender, family history, maximum voided volume in voiding diary (MVV)/expected bladder capacity (EBC) ratio, maximum bladder capacity (MBC)/EBC ratio and pretreatment urinary density, sodium, potassium, calcium levels could not predict complete response (p = 0.292, 0.051, 0.533, 0.552, 0.101, 0.570, 0.326, 0.735, 0.246 respectively).

Conclusions: Desmopressin treatment had no effect on urine density and urinary sodium, potassium, calcium electrolytes similar to the literature. Urine density and electrolyte levels are not helpful in predicting desmopressin treatment response in enuretic children. Low frequency of wet nights (< 17) in a month and single bedwetting at a night are the significant factors to predict complete response to desmopressin treatment in children with primary MNE.

Clinical trial registration: The study does not have a clinical trial registration number, because the study was not a randomized controlled trial and the data in the study were collected retrospectively.