Adult-Onset Still's Disease following Covid-19 Vaccine - A Case Report

The spread of COVID-19 infection has led to rapid vaccine development. It has been shown that vaccination may lead to complications like adult-onset Still's disease. We report a case of a 47-year-old Latvian male who presented with a sore throat, persistent leukocytosis, a high spiking fever, and weakness within two days after receiving the first dose of the Moderna COVID-19 vaccine in April 2021. The patient was initially treated with empirical antibiotics; however, the symptoms did not improve, so glucocorticoids were added, which resulted in the improvement of the patient's condition. The extensive work-up ruled out infection and other inflammatory conditions that mimic AOSD as well as malignancies. The diagnosis of AOSD was established based on anamnesis, radiological and laboratory testing. At the time of the report, several AOSD cases had been reported after COVID-19 vaccine administration. Physicians should consider this condition in patients who have prolonged fever after COVID-19 vaccination, and a diagnosis should be made for proper early management to avoid future complications.