Hypocretin-1 measurements in cerebrospinal fluid using radioimmunoassay: within and between assay reliability and limit of quantification.

ABSTRACT:

Study objectives

The most sensitive and specific investigative method for the diagnosis of narcolepsy type 1 (NT1) is the determination of hypocretin-1 (orexin-A) deficiency (≤110 pg/mL) in cerebrospinal fluid using a radioimmunoassay (RIA). We aimed to assess the reliability of the Phoenix Pharmaceuticals hypocretin-1 RIA, by determining the lower limit of quantification (LLOQ), the variability around the cutoff of 110 pg/mL, and the inter- and intra-assay variability.

Methods

Raw data of 80 consecutive hypocretin-1 RIAs were used to estimate the intra- and inter-assay coefficient of variation (CV). The LLOQ was established and defined as the lowest converted concentration with a CV <25%; the conversion is performed using a harmonization sample which is internationally used

SUBMITTER: van der Hoeven AE 

PROVIDER: S-EPMC9272241 | biostudies-literature | 2022 Jul

REPOSITORIES: biostudies-literature