Key clinical point: A new, more specific marker for macrophage activation syndrome has been identified.
Major finding: Adenosine deaminase 2 above the upper limit of normal is 86% sensitive and 94% specific for distinguishing macrophage activation syndrome from active systemic juvenile idiopathic arthritis, making it perhaps the most potent blood marker yet identified to differentiate the two.
Study details: A mostly cross-sectional investigation of several hundred healthy subjects and children with rheumatic diseases.
Disclosures: The work was funded by the National Institutes of Health, among others. The lead investigator reported having no disclosures.
Lee PY et al. Arthritis Rheumatol. 2019;71(suppl 10), Abstract 920.