Effect of SARS-CoV-2 BNT162b2 mRNA vaccine on thyroid autoimmunity: A twelve-month follow-up study.

Objectives: Graves' disease (GD) has been highlighted as a possible adverse effect of the respiratory syndrome coronavirus-2 (SARS-CoV-2) vaccine. However, it is unknown if the SARS-CoV-2 vaccine disrupts thyroid autoimmunity. We aimed to present long-term follow-up of thyroid autoimmunity after the SARS-CoV-2 BNT162b2 mRNA vaccine. Methods: Serum samples collected from seventy Japanese healthcare workers at baseline, 32 weeks after the second dose (pre-third dose), and 4 weeks after the third dose of the vaccine were analyzed. The time courses of anti-SARS-CoV-2 spike immunoglobulin G (IgG) antibody, thyroid-stimulating hormone receptor antibody (TRAb), and thyroid function were evaluated. Anti-thyroglobulin antibodies (TgAb) and anti-thyroid peroxidase antibodies (TPOAb) were additionally evaluated in thirty-three participants. Results: The median age was 50 (IQR, 38-54) years and 69% were female. The median anti-spike IgG antibody titer was 17627 (IQR, 10898-24175) U/mL 4 weeks after the third dose. The mean TRAb was significantly increased from 0.81 (SD, 0.05) IU/L at baseline to 0.97 (SD, 0.30) IU/L 4 weeks after the third dose without functional changes. An increase in TRAb was positively associated with female sex (ß = 0.32, P = 0.008) and low basal FT4 (ß = -0.29, P = 0.02) and FT3 (ß = -0.33, P = 0.004). TgAb was increased by the third dose. Increase in TgAb was associated with history of the thyroid diseases (ß = 0.55, P <0.001). Conclusions: SARS-CoV-2 BNT162b2 mRNA vaccine can disrupt thyroid autoimmunity. Clinicians should consider the possibility that the SARS-CoV-2 vaccine may disrupt thyroid autoimmunity.

Isolated ACTH deficiency following immunization with the BNT162b2 SARS-CoV-2 vaccine: a case report.

BACKGROUND: The global COVID-19 pandemic requires urgent development of new vaccines. Endocrinological adverse effects following the new mRNA vaccine against COVID-19 have been reported in several cases. Specific to the involvement of pituitary function; however, only a single case with hypophysis has been reported. This is the first case of isolated adrenocorticotropic hormone (ACTH) deficiency (IAD) following mRNA vaccination against COVID-19. CASE PRESENTATION: A healthy 31-year-old man received the BNT162b2 SARS-CoV-2 mRNA vaccine. The first injection was uneventful. One day after the second injection, he noticed general fatigue and fever. In the following several days, he additionally developed headaches, nausea, and diarrhea. Four days after the vaccine injection, he visited a hospital with worsening of these symptoms. Physical examination revealed slight disorientation but no other deficits. Laboratory tests revealed hyponatremia, hypoglycemia, and extremely low plasma ACTH and serum cortisol levels (ACTH < 1.5 pg/ml, cortisol 1.6 µg/dl). He was diagnosed with adrenal crisis and was emergently treated with hydrocortisone. The symptoms responded well and he recovered within a few days. Magnetic resonance images after the replacement with hydrocortisone revealed an atrophic pituitary gland. The patient was referred to our tertiary hospital for further endocrinological examination. Pituitary endocrine load tests revealed isolated adrenocortical response deficiency. After other clinical assessments, he was diagnosed as having isolated ACTH deficiency. After initiation of hydrocortisone replacement, there has been no recurrence of symptoms related to adrenocortical insufficiency nor involvement of other pituitary functions. CONCLUSION: This is the first reported case of IAD potentially associated with COVID-19 immunization. Recent reports have emphasized the importance of adjuvants in the mRNA vaccine that induce the endocrinological adverse effects through disturbance of the autoimmune system, but details are still unclear. Given the broad and rapid spread of vaccinations against COVID-19, it is clinically important to consider that there could be cases with a rare but emergent adrenal crisis even among those who present common symptoms of adverse effects following inactive SARS-CoV-2 mRNA vaccination.