Increased renal concentrating ability after long-term oral desmopressin lyophilisate treatment contributes to continued success for monosymptomatic nocturnal enuresis

Management of treatment-resistant nocturnal enuresis

Nocturnal enuresis is defined as intermittent urinary incontinence during sleep in children 5 years of age and older, occurring at least once a month for at least 3 months. In Japan, pediatricians who do not specialize in nocturnal enuresis have become more proactive in treating the condition since 2016, when the guidelines for treating it were revised for the first time in 12 years. For monosymptomatic nocturnal enuresis, the first step is lifestyle guidance, with a focus on the restriction of fluid intake at night; however, if lifestyle guidance does not decrease the frequency of nocturnal enuresis, aggressive treatment should be added. The first choice of aggressive treatment is oral desmopressin, an antidiuretic hormone preparation, or alarm therapy. However, there remain patients whose wet nights do not decrease with oral desmopressin or alarm therapy. In such cases, it is necessary to reconfirm the method of desmopressin administration and check for factors that may decrease the efficacy of desmopressin. If alarm therapy does not increase the number of dry nights, it is possible that the patient is fundamentally unsuitable for alarm therapy. If dry nights do not increase with oral desmopressin or alarm therapy, the next treatment strategy should be considered immediately to keep the patient motivated for treatment.

Pretreatment morning urine osmolality and oral desmopressin lyophilisate treatment outcome in patients with primary monosymptomatic enuresis

PURPOSE

To determine the association between urine osmolality (Uosm) in patients with primary monosymptomatic enuresis (PMNE) and response to desmopressin (dDAVP) lyophilisate.

METHODS

This was a prospective cohort study that included 419 children with enuresis seen in outpatient clinic between October 2017 and October 2019. Patient workup included symptom checklist, 48 h frequency/volume chart, kidney and bladder ultrasound, uroflow, urinalysis and culture, spot urine Ca/creatinine, and first-morning Uosm. Patients < 5 years, with secondary enuresis, or loss of follow-up were excluded. Oral dDAVP lyophilisate was recommended to all with PMNE and normal bladder capacity. After 1 month of therapy, initial success was assessed according to ICCS. Significant predictor variables for complete response were identified and analyzed using correlation coefficients and binary logistic regression.

RESULTS

There were 48 patients with PMNE who received dDAVP and were followed for treatment success. Partial and complete responses were achieved for 14 (29.2%) and 20 cases (41.7%), respectively. Older age and lower Uosm were found to be significantly in favor of complete response to dDAVP lyophilisate, P = 0.007 and 0.033, respectively. ROC analysis determined the Uosm of ≤ 814 mOsm/kg as a cut-off value for complete success (sensitivity 65% and specificity 75%, AUC = 68.2%). The odds ratio for complete success for selected cut-off value was 5.57 (95% CI 1.588-19.551, P = 0.007).

CONCLUSION

High pretreatment morning Uosm (> 814 mOsm/kg) might be suggestive of an alternative treatment to dDAVP lyophilisate in PMNE because of the higher risk of treatment failure.