Prazosin treatment of neurological patients with lower urinary tract dysfunction

Incomplete emptying and urinary retention in multiple-system atrophy: When does it occur and how do we manage it?

Neurogenic urinary retention can be a major cause of morbidity in multiple-system atrophy (MSA). However, the timing of its appearance has not been entirely clear, and neither have the medical and surgical modalities for managing patients. We present the data obtained from our uroneurological assessment and therapeutic interventions at various stages of MSA. We recruited 245 patients with probable MSA. We measured postvoid residuals (PVR) and performed EMG cystometry in all patients. The grand average volume of PVR was 140 mL (range, 0-760) in our patients. The average PVR volume was 71 mL in the first year, increasing to 129 mL in the second year and 170 mL by the fifth year. The percentages of patients with complete urinary retention, acontractile detrusor, and detrusor-sphincter dyssynergia (DSD) also increased. The increase in PVR resulted in a decrease in functional bladder capacity, together with an increase in detrusor overactivity and neurogenic sphincter EMG. Clean intermittent self-catheterization (CISC) was introduced in most patients. Bladder-oriented therapy (cholinergic agents) had a limited value, whereas urethra-oriented therapy benefited patients with DSD (surgery) for up to 2 years, but syncope occurred in a subset of patients (alpha-blockers). MSA patients present with large PVR by the second year of illness, and that large PVR secondarily causes urinary frequency. CISC is the recommended treatment for most patients. Urethra-oriented medication and surgery benefit patients who would have difficulty performing CISC, although careful consideration of the short-term efficacy and potential adverse effects of these alternatives is mandatory.

Lower urinary tract dysfunction in Machado-Joseph disease: a study of 11 clinical-urodynamic observations

OBJECTIVES

Machado-Joseph disease (MJD), or hereditary spinocerebellar ataxia type 3, is the most common dominantly inherited ataxia. However, lower urinary tract (LUT) dysfunction in MJD has not been fully delineated. We investigated LUT dysfunction in MJD by clinical-urodynamic observations.

METHODS

In 24 genetically diagnosed MJD, we recruited all 11 patients with LUT symptoms (six men, five women; age, 18-61 [mean 48] years; disease duration, 2-24 [mean 9] years; voiding difficulty, 7, urinary incontinence, 4). Urodynamic studies consisted of uroflowmetry, measurement of post-void residuals and electromyography (EMG)-cystometry. Neurophysiology tests consisted of motor unit potential (MUP) analysis of the sphincter and extremity muscles, tibial nerve somatosensory evoked potentials (SEP) and nerve conduction studies (NCS) of the extremities.

RESULTS

Urodynamic abnormalities were seen in all 11 patients studied. Maximum or average flow rate was decreased in five. Post-void residual was noted in three but residual urine volume > 100 ml was noted in only one patient. Maximum urethral closure pressure was low in one and high in one of five patients studied. EMG-cystometry during filling showed detrusor overactivity in five, impaired bladder sensation in four, low compliance detrusor in one, uninhibited sphincter relaxation in one and incompetent urethra in one. Voiding phase abnormalities included detrusor areflexia in three and detrusor-sphincter dyssynergia in two. Bethanechol supersensitivity of the bladder was noted in one of three patients studied. Bulbocavernosus reflex was absent in two of five patients studied. MUP analysis showed neurogenic changes in six of nine sphincter muscles and in all six extremity muscles studied. Five patients had prolonged or absent cortical response in SEP and four had sensory axonal neuropathy in NCS, which were relevant to the impaired bladder sensation.

CONCLUSION

In the present study, a half of MJD patients had LUT symptoms and they showed various urodynamic abnormalities. Detrusor overactivity, impaired bladder sensation, and neurogenic sphincter EMG were common findings, and large post-void residuals were rare. These findings are relevant to central and peripheral nervous system pathology of MJD.

Micturitional disturbance in neuro-Behçet's syndrome

BACKGROUND

Micturitional disturbance is known to occur in neuro-Behçet's syndrome (NBS). However, its pathophysiology is uncertain and few data are available concerning urodynamic findings. We describe our findings on micturitional histories and urodynamic studies in patients with NBS.

METHODS

A history of urinary symptoms was obtained from nine patients with NBS [seven male, two female, aged 26 to 54 years; mean, 41 years]. Neurological and CT/MRI findings indicated that their lesions were located mainly in the cerebral cortex, basal ganglia, cerebellum, brainstem and the spinal cord. Symptomatic patients underwent urodynamic studies, including measurement of post-micturition residuals, urethral pressure profilometry and EMG cystometry.

RESULTS

Six of the nine patients (67%) had urinary symptoms that included diurnal urinary frequency in five, sensation of urgency in five, urge urinary incontinence in five, voiding difficulty in five and nocturnal urinary frequency in four. None had urinary retention. Urodynamic studies performed in six patients showed post-micturition residuals in five (50-180 ml), increased maximum urethral closure pressure in two, decrease in four and increase in one of bladder capacities, detrusor hyperreflexia in five, decreased bladder sensation in one, brisk bulbocavernosus reflex in four, detrusor-sphincter dyssynergia in two and neurogenic sphincter EMG in one.

CONCLUSION

Our results indicate that micturitional disturbance is not rare in patients with NBS. Supranuclear pelvic nerve dysfunction seems to be mainly responsible for the disturbance.

Are alpha-blockers involved in lower urinary tract dysfunction in multiple system atrophy? A comparison of prazosin and moxisylyte

Lower urinary tract dysfunction is a major cause of morbidity in patients with multiple system atrophy (MSA). alpha1-Adrenergic receptors are present in the proximal urethra where impaired relaxation may be responsible for voiding difficulty and a large amount of residual urine. An open study was designed to evaluate whether the blockade of these receptors by prazosin (a nonselective alpha1 blocker) and moxisylyte (an alpha1A-selective blocker) would improve bladder emptying in patients with MSA. Post-micturition residual volumes and clinical symptoms of 49 patients with MSA were evaluated at trial entry and after 4 weeks (prazosin; n=21 and moxisylyte; n=28). The respective means for the prazosin and moxisylyte groups were 38.1% and 35.2% reductions in residual urine volume (P<0.05), and there was lessening of urinary symptoms. Side effects due to orthostatic hypotension were seen in 23.8% of the prazosin group but in only 10.7% of the moxisylyte group. These effects were common in patients with postural hypotension of more than -30 mmHg at trial entry (P<0.05). Modulation of alpha1-receptors may function in the management of lower urinary tract dysfunction in MSA.

Alpha-adrenoceptor antagonists in neurogenic lower urinary tract dysfunction

Lower urinary tract dysfunction is common in patients with a variety of neurological diseases, and may lead to debilitating symptoms and serious complications. Any treatment that can reduce these symptoms or complications is welcome. In many trials, alpha-adrenoceptor antagonists (alpha blockers) have been evaluated as treatment for neurogenic lower urinary tract dysfunction; however, these have generally been small and often nonrandomized, uncontrolled studies. Existing evidence suggests that alpha blockers may have a small but useful effect in the facilitation of storage and emptying, and in the prevention of autonomic dysreflexia. Better understanding of lower urinary tract physiology and larger clinical trials with longer follow-up will hopefully clarify the role of alpha blockers in the future.