Traditional biomarkers in narcolepsy: experience of a Brazilian sleep centre.

UNLABELLED This study was thought to characterized clinical and laboratory findings of a narcoleptic patients in an out patients unit at São Paulo, Brazil. METHOD 28 patients underwent polysomnographic recordings (PSG) and Multiple Sleep Latency Test (MSLT) were analyzed according to standard criteria. The analysis of HLADQB1*0602 allele was performed by PCR. The Hypocretin-1 in cerebral spinal fluid (CSF) was measured using radioimmunoassay. Patients were divided in two groups according Hypocretin-1 level: Normal (N) - Hypocretin-1 higher than 110 pg/ml and Lower (L) Hypocretin-1 lower than 110 pg/ml. RESULTS Only 4 patients of the N group had cataplexy when compared with 14 members of the L group (p = 0.0002). DISCUSSION This results were comparable with other authors, confirming the utility of using specific biomarkers (HLA-DQB1*0602 allele and Hypocretin-1 CSF level) in narcolepsy with cataplexy. However, the HLADQB1*0602 allele and Hypocretin-1 level are insufficient to diagnose of narcolepsy without cataplexy.