Abnormally increased iron concentration in basal ganglia in Shy-Drager syndrome MR imaging and autonomic study: RM imagem e estudo autonômico

Abstract

SUMMARY -Report of an early case of Shy-Drager syndrome in a 67 year-old woman patient. Autonomic failure was diagnosed by functional evaluation as well as laboratory tests. MR imaging disclosed a prominent putamina hypodensity in T 2 -weighted images at high field strength due to iron increased depositing in this basal ganglia. MR imaging evidences confirm Shy-Drager syndrome diagnosis, and contributes for differential diagnosis of idiopathic hypotension (pure autonomic failure) in special in SDS early cases.Concentração de ferro anormalmente aumentada nos núcleos da base na síndrome de Shy-Drager: RM imagem e estudo autonômico.RESUMO -É relatado o caso de unm paciente de 67 anos de idade com quadro inicial da síndrome de Shy-Drager. O diagnóstico foi possível por provas funcionais autonômicas e exames laboratoriais. A ressonância magnética cerebral (contraste baseado na densidade de prótons e em T 2 ) objetivou proeminente hipodensidade putaminal em T 2 , secundária ao aumento do depósito do ferro nesta região. Esse achado da RM confirma o diagnóstico da síndrome de Shy-Drager e permite diferenciá-la da hipotensão ortostática idiopática, particularmente na fase de início da SSD quando os sinais de comprometimento do SNC são discretos ou estão ausentes. The Shy-Drager patients do not respond well to antiparkinsonian drug therapy, and usually succumb to the disease seven to eigth years after its onset and four to five years after CNS disorders outset 35.Postmortem SDS findings include gliosis and/or neuronal loss in the substantia nigra, caudate nucleus, putamen, cerebellar cortex, pontine nuclei, and inferior olives 28.The neuropathologic SDS findings were divided in two groups 24 : the first group is characterized by a striatonigral degeneration with Lewy corps 15,29; the second group by a striatonigral degeneration or olivopontocerebellar atrophy without Lewy corps 31 (two cases in the original Shy-Drager publication).The dominant neurochemical finding in autopsy studies is a severe dopamine decrease in the striatum, substantia nigra, and nucleus accumbens 4 . In vivo studies by evidence of serotonin decrease (autonomic failure) and dopamine decrease (extrapyramidal signs) metabolism in CSF is established by probenecide test 2 4 .