GENITOURINARY DYSFUNCTION IN PERSONS WITH MULTIPLE SCLEROSIS

Genitourinary symptoms may affect up to 90% of persons with Multiple Sclerosis (MS), and may be the presenting symptom in up to 15 % of patients. They are a significant cause of morbidity, non-participation in activities of daily living, time lost from work outside the home, and decreased quality of life. After participating in this educational activity the learner will be able to: 1. Describe the neurophysiology of normal micturition 2. Elicit and recognize common symptoms of bladder dysfunction 3. Prescribe appropriate pharmacologic and non pharmacologic treatment strategies to treat bladder dysfunction 4. List contributing factors to bowel dysfunction in persons with MS 5. Describe approaches to assessment & treatment of sexual dysfunction in persons with MS Neurophysiology of micturition The primary function of the urinary bladder is to store urine and then expel it completely at a socially appropriate time & place. Bladder neurons are contained in the frontal lobes, basal ganglia and midbrain, but ultimately pass through the two main neural control centers of voiding, the Pontine Micturition center(PMC) and Sacral Micturition Center(SMC). The output of the frontal lobes and midbrain are primarily inhibitory, the PMC facilitates voiding, the SMC is more responsible for storage. The sympathetic innervation to the bladder arises in the thoracolumbar (T10-L2) spinal cord, and innervates the bladder as the hypogastric nerve. The parasympathetic innervation to the bladder is primarily carried in the pelvic nerve. Somatic motor innervation is carried in the pudendal nerve, which arises from cell bodies at S2-S4 in Onuf's nucleus, and innervates the urethral sphincter, and pelvic floor. During bladder filling the SMC facilitates continence by increasing bladder wall accommodation and blocking parasympathetic impulses that stimulate bladder wall contractility, increasing outlet resistance and increasing activity in the pelvic floor muscles, the " guarding " reflex. The PMC promotes voiding by inhibiting the guarding reflex, stimulating parasympathetic transmission (to facilitate bladder wall contractility), and relaxing the urethral sphincter. Voiding thus requires coordination between increased contractility of the bladder smooth muscle ad simultaneous relaxation of the sphincter to permit emptying.