A case of multisystem inflammatory syndrome in children presenting as systemic onset juvenile idiopathic arthritis

Area of Science:

• Pediatric Rheumatology
• Infectious Diseases
• Immunology

Background:

• Multisystem inflammatory syndrome in children (MIS-C) is a rare but severe post-COVID-19 complication.
• MIS-C presents with widespread inflammation affecting multiple organ systems.
• It often occurs after a prior SARS-CoV-2 infection, with negative acute tests but positive antibodies.

Observation:

• A 12-month-old girl presented with symptoms mimicking systemic-onset juvenile idiopathic arthritis (SoJIA).
• The child had a positive COVID-19 PCR test.
• Clinical presentation included fever and signs of systemic inflammation.

Findings:

• The case highlights MIS-C presenting atypically as SoJIA.
• Successful treatment was achieved using Dexamethasone and Naproxen.
• This suggests overlapping clinical features between MIS-C and autoimmune conditions.

Implications:

• Recognizing MIS-C's varied presentations is crucial for timely diagnosis.
• Pediatricians should consider MIS-C in children with inflammatory conditions, even with a positive PCR.
• Prompt treatment can prevent severe complications associated with MIS-C.