[Diagnostic accuracy of FP-CIT SPECT in the evaluation of patients with clinically uncertain parkinsonian syndrome].

OBJECTIVE: To determine diagnostic accuracy of FP-CIT SPECT in a subgroup of patients who clinically present nonconclusive or atypical characteristics of parkinsonism (Clinically Uncertain Parkinsonian Syndromes, CUPS), and assess the contribution of the quantitative analysis in this group of patients. PATIENTS AND METHODS: We included 54 patients who make up the CUPS group. After a variable follow-up period, we evaluated the existence of a degenerative parkinsonism and compared it with the result of the FP-CIT SPECT, establishing the diagnostic accuracy of this procedure in the CUPS patient group.
RESULTS: We obtained a high diagnostic accuracy of neurodegenerative Parkinsonism in the CUPS patient group (sensitivity: 85%; specificity: 93%). False positive results were obtained in patients with vascular parkinsonism and most of the false negative results in patients with Parkinson's disease. The quantitative evaluation did not contribute data of relevance to the qualitative evaluation.
CONCLUSIONS: FP-CIT SPECT makes it possible to show the involvement of nigrostriatal dopaminergic pathway, also contributing with information of relevance to the clinician about the etiology of the extrapyramidal symptomatology in patients with nonconclusive signs and symptoms of the existence of a Parkinsonism.