Introduction: Failure of conventional medical treatment in nocturnal enuretic children is often frustrating. Classification system based on urodynamic studies is proposed.

Material & Methods: 120 nocturnal enuretic patients were referred for urodynamic studies after poor response to conventional medical treatment. A full questionnaire, frequency volume chart, clinical examination and full urodynamic studies were performed.

Results: 36% of enuretics showed presence of detrusor instability, 64% of them were observed late in cystometric curve, decreased ability to inhibit voiding in 17%, post micturition contraction in 27%, low bladder capacity in 12%. Based on the above findings:
Patients with enuresis were classified into four groups: Group I with no abnormal findings, Group II with increased detrusor activity, Group III with immature bladder capacity and Group IV with nocturnal polyuria. Group I may responded well to any sort of medical treatment including assurance. Group II can carry good response to parasympatholytics and antidepressants. While Group III may respond to bladder retention training or bladder drilling programs. Group IV can respond excellently to vasopressin.

Conclusion: Treatment based on this information can offer good results and prevents years of unnecessary therapy.