Pituitary and COVID-19 vaccination: a systematic review

Purpose This systematic review aims to examine the latest research findings and assess the impact of COVID-19 vaccination on the pituitary gland.Method PubMed and Tripdatabase were searched from January 1st, 2020 to February 12th, 2024. Case reports, case series and reviews related to post COVID-19 vaccination pituitary disease were included. Eligible articles were tabulated and analysed in the attempt to provide an overview on the epidemiology, clinical presentation, imaging, treatment, outcomes and pathophysiological background of post COVID-19 vaccination pituitary disease.Results Among the 23 case reports included in this review, post COVID-19 vaccination hypophysitis was reported in 9 patients, pituitary apoplexy (PA) in 6 cases, SIADH in 5 cases and Isolated ACTH deficiency in 2 cases. Additionally, precipitating adrenal crisis was registered in 7 patients and pituitary tumor enlargement in 1 patient after receiving COVID-19 vaccination.Conclusion Despite the rarity of these events, our research findings suggest an association between COVID-19 vaccination and the subsequent development of pituitary diseases. The most common manifestations include hypophysitis with ADH deficiency, PA and SIADH, with symptoms typically emerging shortly after vaccine administration. Potential pathogenetic mechanisms include molecular mimicry, vaccine adjuvants and vaccine-induced thrombotic thrombocytopenia (VITT), with the presence of ACE2 receptors in the hypothalamus-pituitary system contributing to the process. These findings can aid in diagnostic and treatment decisions for patients presenting with these syndromes. Nevertheless, given the rarity of these events, safety and efficacy of the currently available COVID-19 vaccines remain robust and we strongly advocate continuing pursuing vaccination efforts.