[Shy-Drager syndrome: a rare cause of orthostatic hypotension]

Abstract

History and admission findings: A 71-year-old man was admitted because of treatment-resistant orthostatic hypotension of unknown aetiology. When aged 64 years he developed some impotence and later urinary incontinence and urinary frequency. At 68 years he noted vertigo on physical activity, and a year later he had signs of reversible cerebral ischaemia. At this point the Schellong test demonstrated vasovagal circulatory dysfunction. After his 70th birthday the unsteadiness on walking and standing got worse and he had recurrent syncopes. He was in a wheel-chair when hospitalized and even the unsteady walk he could maintain for only a few seconds.

Investigations: Plasma and urinary concentrations of catecholamines were at the lower limit of normal but failed to increase during orthostasis. Hormonal, cardiological and infectious causes of the orthostatic hypotension were excluded. Orthostatic tests after Schellong and with the tilting table showed orthostatic hypotension without increased sympathetic activity but hypertensive blood pressure levels during the recumbent period. Intravenous infusion of norepinephrine produced an excess rise in blood pressure (raised norepinephrine sensitivity). The recurrent urinary infection was shown to be due to a hypotonic bladder detrusor muscle. Neurological examination revealed cerebellar dysfunction, signs of pyramidal tract abnormality and sensory polyneuropathy. A Shy-Drager syndrome was diagnosed on the basis of the history, absent blood pressure rise and lack of catecholamine release during orthostasis with increased epinephrine sensitivity and characteristic neurological signs.

Treatment and course: Physiotherapy and elastic stockings with administration of mineralocorticoids as well as of one direct (norfenefrine) and one indirect (amezinium) sympathomimetic drug failed to improve adequately the abnormal orthostatic response. But on additional administration of an alpha 2-receptor antagonist (yohimbine) the patient was able to stand and walk for a few minutes, but the urinary incontinence and the other neurological signs remained treatment-resistant.

Conclusion: If orthostatic hypotension occurs together with neurological symptoms, a Shy-Drager syndrome should be taken into account.