Cut off value of technetium uptake in the differential diagnosis of Graves, disease and subacute thyroiditis

Document Type : Short communication


Department of Nuclear Medicine, Faculty of Medicine, Tokat Gaziosmanpasa University, Tokat, Turkey


Objective(s):The aim of this study was to determine whether technetium (99mTc) uptake is a relevant method for the differential diagnosis of Graves disease and subacute thyroiditis and calculate its cutoff value in case of its relevancy.
Methods: A total of 69 patients, who were followed up (>3 months) in our hospital for thyrotoxicosis within 2015-2019 were enrolled in the study. Out of these 69 subjects, 39 patients had been diagnosed with Graves disease, and 30 of them had subacute thyroiditis. Biochemical parameters, thyroid scintigraphy, and 99mTc uptake test results were evaluated.
Results: 99mTc uptake was significantly higher in the patients with Graves disease than in the patients with subacute thyroiditis (P<0.001). Based on the ROC analysis the 99mTc uptake cutoff value of 1.55% had an accuracy of 92.9%, with the sensitivity and specificity of 92% and 87%, respectively.
Conclusion:In conclusion, the results of our study suggested that 99mTc uptake test could be used in the differential diagnosis of Graves disease and subacute thyroiditis. The cutoff value of 1.55% for 99mTc uptake test may guide in establishing a differential diagnosis between the two diseases.


Main Subjects

  1. Sharma M, Aronow MS, Patel L, Gandhi K, Desai H. Hyperthyroidism. Med Sci Monit. 2011; 17(4): 85-91

  2. Gilbert J.Thyrotoxicosis – investigation and management.Clinical Medicine. 2017; 17( 3): 274–7.

  3. Cooper DS. Hyperthyroidism. The Lancet. 2003; 362: 459-68.

  4. Maısey MN, Natarajan T K, Hurley PJ, Wagner HN. Validation of a Rapid Computerized Method of Measuring 99mTc Pertechnetate Uptake for Routine Assessment of Thyroid Structure and Function. J Clin Endocrinol Metab. 1973; 36: 317-22.

  5. Ross DS, Burch HB, Cooper DS, Greenlee MC, Laurberg P, Maia AL, et al. 2016 American Thyroid Association Guidelines for Diagnosis and Management of Hyperthyroidism and Other Causes of Thyrotoxicosis.Thyroıd. 2016; 26(10): 1343-421.

  6. McGill PE, Harden RM, Robertson IW, Shimmins J. comparison between the uptake of Technetium-99m and Iodine-131 by the thyroid gland.Journal of Endocrinology. 1971; 49(3):531-6l

  7. Macauley M, Shawgi M, Ali T, Curry A, Howe K, Howell B, et al.Assessment of normal reference values for thyroid uptake of technetium-99m pertechnetate in a single centre UK population. Nucl Med Commun. 2018; 39(9):834-8.

  8. Beindorff N, Bartelheimer A, Huang K, Lukas M, Lange C, Huang EL, et al.Normal Values of Thyroid Uptake of 99mTechnetium Pertechnetate SPECT in Mice with Respect to Age, Sex, and Circadian Rhythm. Nuklearmedizin. 2018; 57(5):181-9.

  9. Singhal N, Praveen VP, Bhavani N, Menon AS, Menon U, Abraham N, et al. Technetium uptake predicts remission and relapse in Grave’s disease patients on antithyroid drugs for at least 1 year in South Indian subjects.Indian J Endocrinol Metab. 2016; 20(2): 157–61.

  10. Baskaran C, Misra M, Levitsky LL. Diagnosis of Pediatric Hyperthyroidism: Technetium 99 Uptake Versus Thyroid Stimulating Immunoglobulins. THYROID. 2015; 25(1): 37-41.

  11. Uchida T, Suzuki R, i Kasai T, Onose H, Komiya K, Goto H, et al. Cutoff value of thyroid uptake of 99mTc-pertechnetate to discriminate between Graves’ disease and painless thyroiditis: a single center retrospective study. Endocr J. 2016;63(2):143-9.