Department of Family Medicine (Dr. Momah) and Department of Pediatric Rheumatology (Dr. Ray), University of Mississippi Medical Center, Jackson tmomah@umc.edu
The authors reported no potential conflict of interest relevant to this article.
Macrophage-activating syndrome increases risk of morbidity, mortality
An overactivation and expansion of T lymphocytes and macrophagic histiocytes with hemophagocytic activity, macrophage-activating syndrome (MAS) occurs in approximately 10% of JIA patients,27 increasing their risk of morbidity and mortality. The syndrome, which typically presents as fever, seizures, hypotension, purpura, hepatitis, splenomegaly, and occasionally, multisystem organ failure, is seen in 30% to 40% of sJIA patients; approximately 11% of them experience sudden death as a consequence.28
The clinical setting of MAS includes presenting symptoms of fever and a salmon-pink macular rash (FIGURE). For many sJIA patients with MAS, the diagnosis is made when laboratory results show hyperferritinemia, thrombocytopenia, anemia, leukopenia, coagulopathy, and elevated levels of C-reactive protein and D-dimer.27
Different classes, different features
The following clinical profiles have been documented in different classes of JIA:
Systemic JIApresents with intermittent fever of at least 2 weeks’ duration, arthritis, and occasionally, a rash.
Extended oligo-articular JIA involves pain, in a mono-articular lower-extremity joint, that can develop suddenly or insidiously, and is characterized by early-morning stiffness and uveitis (especially in early-onset, antinuclear antibody-positive JIA patients).
