Journal of Endocrinological Investigation https://doi.org/10.1007/s40618-020-01366-7 LETTER SARS‑COV‑2 as a trigger for autoimmune disease: report of two cases of Graves’ disease after COVID‑19 M. Mateu‑Salat1 · E. Urgell2 · A. Chico1,3,4 Received: 7 July 2020 / Accepted: 15 July 2020 © Italian Society of Endocrinology (SIE) 2020 To the Editor Upon physical examination, no goiter was found and she Since the outbreak of the SARS-CoV-2 pandemic, there referred no cervical pain. TSH receptor antibodies were pos- have been many reports of autoimmune diseases triggered by itive (2.13 IU/L, normal range < 1.75) and thyroperoxidase or related to COVID-19 such as Guillain–Barre’s syndrome, and thyroglobulin antibodies were also positive (1343 IU/ autoimmune haemolytic anaemia, autoimmune thrombotic mL, normal range < 100; 199 IU/mL, normal range < 138; thrombocytopenic purpura or autoimmune thrombocyto- respectively). Thyroid iodine uptake was increased to 30% penic purpura. Regarding thyroid disease, there have been and 45.7% at 2 and 24 h after administration of 100 μCi of three case reports of subacute thyroiditis [1–3] but, as far iodine (I131). as we know, there have been no reports about autoimmune A 53-year-old woman experienced dyspnoea and fever hyperthyroidism. starting on March 17th, 2020. A naso-pharyngeal swab test We hereby describe two cases of autoimmune hyper- for SARS-CoV-2 was negative but chest X-ray showed bilat- thyroidism (Graves’ disease) occurring after SARS-CoV-2 eral interstitial pneumonia compatible with COVID-19. She infection. did not require hospitalisation and was treated symptomati- A 60-year-old woman with a previous diagnosis of cally. No iodine-containing drugs were given. Infection by Graves’ disease at the age of 23 years, treated with thia- SARS-CoV-2 was later confirmed by positive IgG on April mazole and who had been in remission since the age of 20th, 2020. Due to persisting asthenia and onset of tremor 25 years with a normal thyroid function on the last check- and palpitations, thyroid function was assessed on May 21st, up (September 2019). She presented to the primary care 2020, showing suppressed serum TSH (< 0.01 mIU/mL) center with dyspnoea and chest pain in April 16th, 2020. with increased serum-free thyroxine (FT4 36.5 pmol/L). A naso-pharyngeal swab test for SARS-CoV-2 was nega- Physical examination revealed a non-tender goiter. TSH tive but lung ultrasound showed an interstitial pattern com- receptor antibodies were positive (6.07 IU/L), as well as patible with COVID-19 pneumonia and both IgM and IgG thyroperoxidase and thyroglobulin antibodies (3239 IU/mL against SARS-CoV-2 were positive 4 days later. After clini- and 1617 IU/mL, respectively). Iodine-uptake was increased cal improvement, she presented to the emergency room on to 61 and 62% at 2 and 24 h respectively. May 25th, 2020, with palpitations, nervousness and fatigue. Therapy with thiamazole and propranolol was started to Thyroid function was assessed, showing suppressed TSH both patients with improvement of symptoms and thyroid (< 0.01 mIU/mL, normal range 0.3–5), normal free thyrox- function. ine (FT4 16 pmol/L, normal range 9–19) and elevated free Clinical presentation, increased thyroid uptake and posi- triiodothyronine (FT3 7.93 pmol/L, normal range 2.63–5.7). tive TSH receptor antibodies are compatible with a diagno- sis of Graves’ disease (autoimmune hyperthyroidism). Both * M. Mateu‑Salat cases of hyperthyroidism were diagnosed 1 and 2 months m.mateu7@gmail.com after the clinical onset of COVID-19. 1 In conclusion, we report two cases of Graves’ disease Endocrinology and Nutrition Department, Hospital de La after COVID-19, one with a previous history of Graves’ dis- Santa Creu I Sant Pau, Barcelona, Spain 2 ease in remission for more than 30 years, and another with Biochemistry Department, Hospital de La Santa Creu I Sant no previous known thyroid disease. Of course, with Graves’ Pau, Barcelona, Spain 3 disease being the most frequent cause of hyperthyroidism, Universitat Autònoma de Barcelona, Barcelona, Spain especially in middle-aged women, the association might be 4 CIBER-BBN, Madrid, Spain 13 Vol.:(0123456789) Journal of Endocrinological Investigation casual. However, the increasing number of publications on or national research committee and with the 1964 Helsinki Declaration autoimmune diseases related to COVID-19 suggests that and its later amendments or comparable ethical standards. The ethical committee approval is not required for case reports. SARS-CoV-2 could act as a trigger of latent or new-onset autoimmunity. Physicians and especially endocrinologists Informed consent Signed consent was obtained from both patients. should be aware of possible connections between SARS- Data were anonymized. CoV-2 and thyroid dysfunction, both subacute thyroiditis [1–3] and Graves’ disease, which should be investigated by future prospective studies. Reference 1. Asfuroglu Karkan E, Ates I (2020) A case of subacute thyroiditis Acknowledgements The authors want to thank colleagues working associated with Covid-19 infection. J Endocrinol Invest. https​:// in the Nuclear Medicine Department [Monsterrat Estorch MD, Valle doi.org/10.1007/s4061​8-020-01316​-3 Camacho MD, Joan Duch MD, Francisco Fuentes MD, Safae Abouzian 2. Ippolito S, Dentali F, Tanda ML (2020) SARS-CoV-2: a poten- MD); colleagues from the Biochemistry Department (Madalina Nico- tial trigger for subacute thyroiditis? Insights from a case report. leta Nan MD, José Rives MD); colleagues from the Endocrinology and J Endocrinol Invest. https​://doi.org/10.1007/s4061​8-020-01312​ Nutrition Department (Lilian Mendoza MD, Idoia Genua MD, Queralt -7(published online ahead of print, 2020 Jun 2) Asla MD, Èlia Álvarez MD) for their participation; and Prof. Susan M. 3. Brancatella A, Ricci D, Viola N, Sgrò D, Santini F, Latrofa F Webb for her comments and suggestions on the manuscript. (2020) Subacute thyroiditis after Sars-COV-2 infection. J Clin Endocrinol Metab 105(7):dgaa276. https​://doi.org/10.1210/cline​ Funding The authors received no specific funding for this work. m/dgaa2​76 Publisher’s Note Springer Nature remains neutral with regard to Compliance with ethical standards jurisdictional claims in published maps and institutional affiliations. Conflict of interest All authors declare that they have no conflicts of interest. Ethical approval All procedures performed during this retrospective study were in accordance with the ethical standards of institutional and/ 13