Can thyroid stimulating hormone levels by TSH (IRMA) predict relapse of thyrotoxicosis following carbimazole treatment

Serum thyrotrophin receptor antibody (TRAb) and thyroid stimulating hormone (TSH) (IRMA) levels were measured in 38 patients at one month after the end of a course of carbimazole/T3 therapy for Graves' disease. Despite the increased sensitivity of the IRMA assay a TSH measurement at this stage was found to be of no predictive value, in contrast to estimation of serum TRAb levels which correctly predicted relapse and remission in 90% of patients.