In vitro effect of dipyrone on several peroxidase labelled immunoassays.

We studied the in vitro effect of dipyrone on the determination of free triiodothyronine (free T3), cortisol, progesterone, estradiol, carcinoembryonic antigen, human chorionic gonadotropin and alpha-fetoprotein measured with an immunoenzyme assay based on enhanced luminescence that uses peroxidase as label. We found significant interference from dipyrone (p < 0.01) in the determination of all the analytes mentioned: for progesterone and estradiol the interference was present at high doses of dipyrone; for free T3 and cortisol the minimum dipyrone concentration producing interference was 712 mumol/l and for carcinoembryonic antigen, human chorionic gonadotropin and alpha-fetoprotein 44 mumol/l.

Evaluation of Ciba Corning ACS:180 automated immunoassay system.

We evaluated the technical performance of the Ciba Corning ACS:180 automated immunoassay system for the following analytes: thyroid-stimulating hormone, free thyroxine, luteinizing hormone, follicle-stimulating hormone, prolactin, human chorionic gonadotropin, carcino-embryonic antigen, and prostate-specific antigen. The characteristics evaluated were: precision, carryover, linearity, lower limit of detection, analytical interferences, and comparison with other methods. Satisfactory results were obtained in the within-run and between-run precision studies.

[Evaluation of a new strategy for detecting thyroid dysfunction].

The results of a diagnostic strategy to evaluate thyroid function were assessed. This strategy consists of TSH measurement as the initial biochemical test, assuming that all individuals with normal TSH concentrations are euthyroid and do not require additional measurements of other hormones. The study was carried out in 576 patients whose serum samples had been referred to the laboratory during 4 consecutive weeks for the evaluation of thyroid function.

Technical and clinical performance of six sensitive immunoradiometric assays of thyrotropin in serum.

We evaluated the analytical and clinical performance of six commercial immunoradiometric assay kits for thyrotropin (TSH) in serum in 218 subjects, with and without thyroid dysfunction. Detection limits of the six kits were lower (from 0.07 to 0.