Background. Nocturnal enuresis (NE), defined as intermittent involuntary urine leakage during sleep, affects approximately 16% of children at age 5 and 10% at age 7, with prevalence declining with age. Aim. To evaluate the urodynamic features of patients with non-monosymptomatic nocturnal enuresis (NMNE). Methods. This cross-sectional study was conducted from June 2015 to September 2020 in a surgical subspecialty hospital within a major medical city complex, including 237 patients. Eligible patients were older than seven years, diagnosed with NMNE, and had refractory enuresis, defined as persistent symptoms despite at least six months of continuous medical treatment. All patients underwent a detailed history, bladder diary review, clinical examination, lumbosacral spine X-ray, and, when indicated, MRI or cystoscopy. Invasive multi-channel urodynamic studies were performed using the MMS Solar Gold system. A dual-lumen 6 Fr transurethral catheter measured intravesical pressure and bladder filling, while a rectal balloon catheter measured abdominal pressure. Patients were positioned in a seated or semi-recumbent posture to replicate physiological voiding conditions. Recorded parameters included bladder capacity, detrusor activity, bladder compliance, sphincter behavior, urinary flow rate, post-void residual volume (PVR), and urethral pressure profiles. Data were analyzed using IBM SPSS v.26, with p < 0.05 considered statistically significant. Results. A total of 237 patients were enrolled (mean age 19.2 ± 12 years). Primary NE was observed in 168 (70.9%) and secondary NE in 69 (29.1%). Bladder overactivity was present in 201 (84.8%). Compliance was significantly higher in overactive than non-overactive bladders, while post-void residual was significantly higher in non-overactive patients. No significant differences were found for bladder capacity, urethral pressure profile, filling IV pressure, or flow rate (p > 0.05). Detrusor–sphincter dyssynergia was present in 30.8%, high post-void residual in 80.0%, high urethral pressure profile in 57.0%, and low urethral pressure profile in 12.6%. Conclusion. Urodynamic evaluation is essential for guiding the management of patients with treatment-refractory NMNE.
