[Contribution of chemiluminescence for determination of low value TSH in patients with dysthyroidism during negative TRH test]. / Apport de la chimiluminescence au dosage de valeurs basses de TSH chez des patients souffrant de dysthyroïdie lors de test à la TRH non répondant.

TSH values performed by immunoradiometric method were compared with chemiluminescent method in 28 hyperthyroid patients with negative TRH-test. This last method gives a better sensitivity (0.020 mUI/L vs. 0.050 mUI/L) and reproducibility (5% V.C. vs. 40%). The measure of undetectable TSH by immunoradiometric assay becomes possible with chemiluminescence. Due to this increase of sensitivity, the TRH-test needs to be reconsidered and allows to discriminate various degrees of TSH suppression.