Urinary retention and sympathetic sphincter obstruction in axonal Guillain-Barré syndrome.

A 62-year-old woman with axonal Guillain-Barré syndrome developed weakness and urinary retention simultaneously. The retention failed to recover for 10 months even after she regained the ability to walk. The patient exhibited no postural hypotension. Videourodynamics showed that the retention was caused not by the bladder paralysis but rather by internal (sympathetic) sphincter obstruction, which is extremely uncommon in peripheral neuropathies. We started the patient on an alpha-adrenergic antagonist, urapidil, at 30 mg/day, and this led to successful relaxation of the urethra and reduced the postvoid residual from 200 ml to less than 30 ml. The underlying mechanisms of urinary retention in our patient appeared to involve hyperactive lumbosacral sympathetic nerves. Urinary retention and sympathetic sphincter obstruction can thus be features of axonal Guillain-Barré syndrome.