title: Multicenter study of Abbott AxSYM Digoxin II assay and comparison with 6 methods for susceptibility to digoxin-like immunoreactive factors.
abstract: Performance characteristics of the Abbott nonpretreatment AxSYM Digoxin II assay were evaluated for quantification of digoxin at four independent sites. Correlation of digoxin measurements with the Abbott pretreatment AxSYM, Baxter Stratus II, Abbott TDx/ TDxFLx II, Abbott IMx, Emit 2000, and Beckman Synchron CX digoxin assays showed acceptable agreement, as indicated by: slope values > 0.84, r > 0.90, y-intercepts for all comparisons at or below the assay detection limit, and Sy/x ranging between 7.5% and 15.4% of the average digoxin value. Susceptibility to interference from digoxin-like immunoreactive factors (DLIFs) was examined in 233 samples from renal patients, liver disease patients, cord blood, and third-trimester pregnancies; the AxSYM Digoxin II assay demonstrated the least DLIFs interference. DLIF susceptibility for four of the methods was significantly greater (P < 0.05) than in the AxSYM Digoxin II assay; susceptibilities of the Stratus II and Emit 2000 methods were similar to the AxSYM Digoxin II assay.
authors.affiliation: Department of Pathology, University of Maryland School of Medicine, Baltimore 21201, USA. hazzazy@umabnet.ab.umd.edu
authors.forename: H M
authors.initials: HM
authors.lastname: Azzazy
authors.forename: S H
authors.initials: SH
authors.lastname: Duh
authors.forename: A
authors.initials: A
authors.lastname: Maturen
authors.forename: E
authors.initials: E
authors.lastname: Schaller
authors.forename: L
authors.initials: L
authors.lastname: Shaw
authors.forename: R
authors.initials: R
authors.lastname: Grimaldi
authors.forename: G
authors.initials: G
authors.lastname: Shock
authors.forename: R H
authors.initials: RH
authors.lastname: Christenson
mesh_terms: D001322:Autoanalysis / Q000295:instrumentation / Q000379:methods; D001331:Automation / Q000295:instrumentation / Q000379:methods; D004077:Digoxin / Q000097:blood*; D005189:False Positive Reactions; D005260:Female; D005312:Fetal Blood; D006801:Humans; D007118:Immunoassay / Q000379:methods; D007124:Immunoenzyme Techniques; D007202:Indicators and Reagents; D007674:Kidney Diseases / Q000097:blood; D008107:Liver Diseases / Q000097:blood; D011247:Pregnancy; D011261:Pregnancy Trimester, First; D012044:Regression Analysis; D015203:Reproducibility of Results
chemical_list: D007202:Indicators and Reagents; D004077:Digoxin