A case of macrophage activation syndrome in a patient with anti-synthetase syndrome.

Anti-synthetase syndrome (ASS) is an autoimmune disease characterized by autoantibodies against an aminoacyl transfer RNA synthetase with clinical features including interstitial lung disease, non-erosive arthritis, myositis, Raynaud's phenomenon, unexplained fever and/or mechanic's hands. Macrophage activation syndrome (MAS) is a potentially fatal hyper- inflammatory syndrome that can occur as a complication of systemic rheumatic diseases. However, the association of MAS and ASS has rarely been reported in the literature. Here, we report this association in a patient with overlap ASS and anti-CCP positive rheumatoid arthritis. First line management with steroids was complicated by diabetic ketoacidosis, hence requiring use of anti-IL1 therapy (anakinra) for disease control.