Monosymptomatic and non-monosymptomatic nocturnal enuresis: a clinical evaluation.

Background: Nocturnal enuresis is divided into monosymptomatic nocturnal enuresis (MNE) and non-monosymptomatic nocturnal enuresis (NMNE). This study reviews clinical and ultrasonography (US) findings in enuretic children, and compares the organic and functional pathologies of the lower urinary tract (LUT) in children with MNE to those who have NMNE.
Methods: We enrolled 111 neurologically normal children with chief complaints of enuresis in this study. Participants included 60 boys and 51 girls, aged 5 - 17 years. There were 43 (38.8%) patients diagnosed with MNE and 68(61.2)% with NMNE. Urine analysis, urine culture and kidney-bladder US were performed for patients. Some patients underwent a voiding cystoureterography (VCUG), urodynamic study (UDS), or both. 
Results: Patients were divided into three groups: i) MNE, ii) NMNE without daytime incontinence (NMNE - daytime incontinence), and iii) NMNE plus daytime incontinence (NMNE + daytime incontinence). Constipation (P = 0.011), encopresis (P = 0.003) and urge incontinence (P = 0.001) were significantly more frequent in patients with NMNE +daytime incontinence. Bladder wall thickness (BWT) was the most common US finding. One patient with MNE and 9 with NMNE+ daytime incontinence had vesicoureteral reflux (VUR; P = 0.016). Posterior urethral valve (PUV) was reported in one patient with NMNE.  Evidence of bladder dysfunction was noted in about half of the patients who underwent UDS, with a higher prevalence in cases that had NMNE +daytime incontinence (P = 0.297). Bowel symptoms and VUR were significantly more prevalent in cases with NMNE + daytime incontinence. 
Conclusion: We recommend VCUG in enuretic children who have daytime incontinence. In addition our study has revealed that symptoms suggestive of an overactive bladder (OAB) are not good indicators for bladder dysfunction.