Endocrine Abstracts

Introduction: Inappropriate laboratory test utilization can result in unnecessary patient testing and increased healthcare costs. Thyroid-stimulating hormone (TSH) is recommended as the first-line test for investigating and monitoring thyroid dysfunction. We evaluate Thyroid function tests (TFTs) ordering in our hospital practice.

Methods: A retrospective descriptive study included 400 TFTs requests. TFTs of interest were: TSH and FT4. These tests request were classified according to the reasons and origins of ordering. Frequencies of each testing pattern were calculated. Demographic data (sexe, age) are determinate. Thyroid stimulating hormone (TSH), free thyroxine (FT4) were performed based on electrochemiluminescence immunoassay (eCLIA) by Dxi600® Beckman Coulter.

Results: The mean age of patients was 46.7 years, with extremes ranging from 1 month to 86 years with a male/female sex ratio of 0.49. The majority of TFTs requests were from the endocrinology department (43.3%), followed by the cardiology department (12.8%) and the paediatrics department (11.9%). Reasons for prescription were dysthyroid follow-up in 37.3% of cases, suspicion of dysthyroidism in 37% of cases, dysthyroid screening in 23.7% and the presence of thyroid nodules in 2%. TFTs’s ordering were for TSH alone in 78.5% of cases, and a TSH+FT4 in 21, 5% of cases. Among subjects suspected of having dysthyroidism and subjects having thyroid nodule only 40% had dysthyroidism (35% had hypothyroid and 5% had hyperthyroid) and only % had dysthyroidism (% had hypothyroid and % had hyperthyroid) respectively. Among subjects who underwent a thyroid check for dysthyroidism, 65% returned normal, 17% with hypothyroidism and 2% with hyperthyroidism. Among subjects with a thyroid nodule or goitre, only 28.6% had hypothyroidism, the rest returned normal.

Conclusion: There was an over-ordering for thyroid tests in our hospital practice. This suggests that this request should be more rational in order to limit costs and invasiveness.