Electrophysiologic studies and clinical findings in females with combined fecal and urinary incontinence: a prospective study.

Purpose: Several clinical, urodynamic, and manometric findings suggest neurologic damage as a contributing factor in the development of combined fecal and urinary incontinence. In this study, we wanted to test the hypothesis of pudendal nerve neuropathy being a more frequent lesion in patients with double incontinence compared with patients with isolated fecal incontinence.

Patients: Ninety-three females with combined fecal and urinary incontinence and 36 females with isolated fecal incontinence were investigated. All patients underwent anal manometry, endoanal ultrasound, electromyography, and pudendal nerve terminal motor latency.

Results: No statistically significant differences were found in the age, history of vaginal delivery, and chronic straining between both groups. However, the rate of postmenopausal females was higher in the combined fecal and urinary incontinence group (85 vs. 67 percent; P = 0.02). Menopause was an independent risk factor of having double incontinence (odds ratio, 1.4; P = 0.02). Concentric needle electromyography of the external anal sphincter revealed increased duration of the motor unit potentials in 43 and 53 percent of patients with combined fecal and urinary incontinence and isolated fecal incontinence, respectively (P = 0.28). An increased number of polyphasic motor unit potentials was detected in 52 and 58 percent (P = 0.6). There was no statistically significant difference in the prevalence of bilateral (20 vs. 27 percent) or unilateral (23 vs. 14 percent) prolonged mean pudendal nerve terminal motor latency between both groups (P = 0.3).

Conclusions: Pudendal neuropathy is not a distinct characteristic of patients with double incontinence. The prevalence of pudendal neuropathy in these patients is similar to that observed in patients with isolated fecal incontinence. Others factors should be investigated to explain the common association of both types of incontinence.