Background Macrophage activation syndrome (MAS) is a rare hyperinflammatory condition characterised by macrophage activation and infiltration resulting in a multi organ damage. MAS is considered to be a type of secondary hemophagocytic lymphohistiocytosis. It is a life threatening complication of various autoimmune or autoinflammatory rheumatic diseases, particularly systemic juvenile idiopathic arthritis (sJIA). Clinical manifestations include hepatosplenomegaly, increase of liver function tests, pancytopeny, neurolological manifestations etc. High doses of glucocorticosteroids (GC), cyclosporine A (CyA) and etoposide are a treatments of choice. In refractory cases biologicals may be an option, too.
Objectives To point out this very rare but severe complication may occur also in adult patients with rheumatic diseases.
Methods We report 4 successfully treated cases of adult MAS in rheumatic patients seen in our clinic during the years 2009 – 2016. A review of the literature regarding the efficacy of biologics in MAS treatment is also presented.
Results We have observed four patients with MAS, two with adult onset Still disease (AOSD), one with rheumatoid arthritis (RA) and one with sJIA. All of the patients were young (20 -33 years, mean age 27,0±5,61 years) with the duration of the primary disease ranging from 9 months to 11 years (mean 4,18±4,01 years). Three patients were in remission of the primary diseases prior to MAS manifestation, only in the last and most severe patient (AOSD) the activity of the underlying disease was not controlled. A demographic and clinical characteristic of the patients is summarized in the table.
All 4 patients were successfully treated, one with high doses of glucocorticosteroids (GC), two with combination GC plus CyA. The last and most severe one had MAS refractory to the combination GC + CyA and must have been added biological therapy (tocilizumab). We reviewed also another cases of MAS treated with biologics which have been published.
Conclusions Our cases illustrate that MAS may develop also in adult patient with various rheumatic diseases (JIA, AOSD, RA) despite the low activity or remission. It occurs particularly in younger subjects. As the MAS symptoms may overlap with the symptoms of the primary disease (JIA, AODS) the diagnosis may be difficult. MAS must be suspected in inflammatory rheumatic diseases patients with sudden increase of CRP, extreme increase of ferritin, liver function tests and decrease of platelets. An immediate treatment with GC, CyA and etoposide is essential; biologicals (anakinra, canakinumab or tocilizumab) may be benefitial in refractory cases.
Acknowledgements Supported by MHCR Research project 00000023728.
Disclosure of Interest None declared