title: Anomalous serum thyroxin measurements with the Abbott TDx procedure.
abstract: We describe a patient whose serum gave consistently low results for thyroxin as measured with the Abbott TDx but normal results by radioimmunoassay. Further clinical and laboratory studies did not support the low TDx results. Anti-thyroxin antibodies did not explain the discordant results, and we found no evidence of heterophilic antibodies in the patient's serum. We were unable to identify the cause of the problem.
authors.affiliation: Clinical Laboratory, VA Medical Center, Martinez, CA 94553.
authors.forename: S
authors.initials: S
authors.lastname: Levine
authors.forename: R
authors.initials: R
authors.lastname: Noth
authors.forename: A
authors.initials: A
authors.lastname: Loo
authors.forename: I J
authors.initials: IJ
authors.lastname: Chopra
authors.forename: G G
authors.initials: GG
authors.lastname: Klee
mesh_terms: D000328:Adult; D000906:Antibodies / Q000032:analysis; D003951:Diagnostic Errors; D004586:Electrophoresis; D005188:False Negative Reactions; D006801:Humans; D007037:Hypothyroidism / Q000097:blood; D007118:Immunoassay; D008297:Male; D011863:Radioimmunoassay; D013974:Thyroxine / Q000097:blood* / Q000276:immunology / Q000592:standards; D013975:Thyroxine-Binding Proteins / Q000032:analysis
chemical_list: D000906:Antibodies; D013975:Thyroxine-Binding Proteins; D013974:Thyroxine