Reactive arthritis after COVID-19 vaccination.

Area of Science:

• Immunology
• Vaccinology
• Rheumatology

Background:

• The global COVID-19 pandemic necessitates widespread vaccination efforts.
• Vaccines are crucial for controlling infectious disease spread but can rarely cause adverse events.
• Reactive arthritis (ReA) is a known post-vaccination complication, though not previously reported for COVID-19 vaccines.

Observation:

• A 23-year-old woman presented with acute, painful swelling of her left knee joint for 18 days.
• The onset of symptoms followed administration of the CoronaVac vaccine.
• The patient received two doses of the CoronaVac vaccine via deltoid intramuscular injection.

Findings:

• The patient was diagnosed with reactive arthritis subsequent to COVID-19 vaccination.
• Treatment with a single intra-articular injection of compound betamethasone resulted in significant symptom improvement within 2 days.
• Full recovery was observed at the 1-month follow-up, indicating a favorable prognosis with appropriate management.

Implications:

• This case represents the first reported instance of reactive arthritis following COVID-19 vaccination.
• While rare, this adverse event underscores the importance of monitoring vaccine safety and reporting potential side effects.
• Further research is warranted to identify individuals at higher risk for autoimmune conditions post-vaccination and to develop safer vaccine formulations.