Macrophage activation syndrome (MAS) is a rare and life threatening complication of
rheumatic diseases. It is seen most frequently in association with systemic onset
juvenile idiopathic arthritis and less commonly in other rheumatic diseases of childhood
including systemic lupus erythematosus. Recognition of MAS in patients with rheumatic
diseases is often challenging as it may mimic the clinical features of the underlying
disease. Sometimes MAS can be the mode of initial presentation adding to the diagnostic
complexity. We describe two cases of MAS in association with systemic onset juvenile
idiopathic arthritis who presented with a clinical picture suggestive of septic shock.
The Internal Review Board at Shands Children’s Hospital and the University of Florida
waived the need for approval for these case reports.
Keywords
Systemic onset juvenile idiopathic arthritis - macrophage activation syndrome - rheumatic
disease
