Potential multisystem degeneration in Asidan patients.

OBJECTIVE

To evaluate a potential multisystem involvement of neurodegeneration in Asidan, in addition to cerebellar ataxia and signs of motor neuron disease.

METHODS

We compared the new Asidan patients and those identified in previous studies with Parkinson's disease (PD, n=21), and progressive supranuclear palsy (PSP, n=13) patients using 123I-2β-Carbomethoxy-3β-(4-iodophenyl)-N-(3-fluoropropyl) nortropane (123I-FP-CIT) dopamine transporter single photon emission computed tomography (DAT-SPECT) and 123I-metaiodobenzylguanidine (MIBG) myocardial scintigraphy (Asidan, DAT: n=10; MIBG: n=15).

RESULTS

Both the PD and PSP groups served as positive controls for DAT decline. The PD and PSP groups served as a positive and negative control, respectively, of MIBG decline in the early phase H/M ratio. Of the Asidan patients, 60.0% showed DAT decline without evident parkinsonian features and 6.7% showed impaired MIBG in only the delayed phase H/M ratio. Combined with a normal range of the early phase H/M ratio, this phenotype was newly named Declined DAT Without Evident Parkinsonism (DWEP).

INTERPRETATION: The results of present study including DWEP suggest a wider spectrum of neurodegeneration for extrapyramidal and autonomic systems in Asidan patients than expected, involving cerebellar, motor system and cognitive functioning.