SUMMARY
A woman in her 50s with a history of stable ulcerative colitis for 20
years, managed using salazosulfapyridine, presented with migratory
rashes, spiking fever, edema, and joint pain that started one week after
receiving the BNT162B2 mRNA vaccine against severe acute respiratory
syndrome coronavirus 2 (SARS-CoV-2). Laboratory tests revealed extremely
high serum ferritin levels. The patient was diagnosed with adult-onset
Still’s disease (AOSD) based on the relevant classification criteria
after ruling out other diseases. Detection of high levels of
interleukin-18, an inflammatory cytokine related to AOSD, supported the
diagnosis. Non-steroidal anti-inflammatory drug monotherapy alone
resulted in significant improvements of both the abovementioned symptoms
and the elevated inflammatory marker levels. AOSD in a patient with
ulcerative colitis is extremely rare. Only one case of AOSD with
ulcerative colitis was reported before the coronavirus disease 2019 era.
This case indicates that SARS-CoV-2 vaccination can trigger a
hyperinflammatory response classified as AOSD in a patient with
ulcerative colitis, which is extremely rare.