Abstract
BACKGROUND: Pituitary apoplexy is a rare endocrine emergency, which commonly presents with headache and is occasionally associated with visual disturbances. Prompt diagnosis and treatment can be both life and vision saving. In the emergence of novel coronavirus and global pandemic, rapid development of new vaccines have shown to reduce morbidity and mortality associated with Covid-19. Recognition of rare potential adverse effects of these vaccines including pituitary apoplexy are yet to be reported. A causal link between pituitary apoplexy and COVID-19 vaccination has not been established. CASE PRESENTATION: We report a case of a 24-year-old woman who presented with progressively worsening headache soon after completing her COVID-19 vaccination. Imaging showed pituitary apoplexy with an underlying pituitary mass. In view of the age and the typical presentation of severe headache, pituitary hypophysitis was considered, despite the absence of the almost pathognomonic feature of a thickened pituitary stalk in the initial imaging. In the context that the headache had started shortly after the administration of the second dose of COVID-19 vaccine, this potentially could have been the trigger for the occurrence of pituitary apoplexy. CONCLUSION: Although the pathophysiology is not entirely clear and no direct link could be ascertained, our patient may have developed an exaggerated immunological response after the vaccine, with a possible pituitary hypophysitis leading to a pituitary apoplexy.