Background Macrophage activation syndrome (MAS) is an infrequent disease characterized by clinical signs and symptoms of extreme inflammation, it can be associated with severe clinical manifestations and death. MAS can occur in the setting of an active systemic disease (malignancy or rheumatic disease) or an active infection. There is a paucity of data regarding MAS and rheumatic diseases.
Objectives To describe clinical and laboratory characteristics, treatment modalities and treatment results in patients with MAS associated with Rheumatic diseases in a high complexity health center.
Methods Six patients were found in the clinical registry of the Rheumatology service of the Hospital Universitario 12 de Octubre in Madrid, Spain, from the years 2007 to 2011. Their clinical history charts and laboratory exams where revised in a retrospective way. Patients with malignancy were not included
Results Four patients had Systemic Lupus Erythematosus (SLE) and two had systemic Juvenile Idiopathic Arthritis (sJIA). The mean age was 24.6±7.8 years; only one patient was male (with SLE). Their clinical characteristics were: fever (100%), skin lesions (83%), hepatomegaly (66%), arthritis (66%), splenomegaly (50%), oral lesions (50%), lung involvement (33%) and central nervous system involvement (33%), only one patient had intravascular disseminated coagulation. In 50% of the cases the trigger factor was an infection (with a Type 6 Herpes Virus infection included).
Suppression of two cell lines was present in 83% of the patients, with lymphopenia in 100% of them. Eighty three percent had anemia and 50% had thrombocytopenia. Five patients had fibrinogen levels below 200 mg/dl. All patients had hepatic cytolysis (average AST 476 IU/L ± 443), elevated ferritin level (average 6634±3870 ng/ml), elevated triglyceride levels (446±159 mg/dl), lactate dehydrogenase elevation (2443±1886 U/L), elevated C-reactive protein (7.07±3.31 mg/dl), elevated erythrocyte sedimentation rate 83% (54.5±30 mm/h). Of the 4 patients with SLE, all of them had low C3 levels (94±63 mg/dl, with a range of 47-216 mg/dl). Hemophagocytosis was present in all of the bone marrow examinations.
All the patients received initial broad spectrum antibiotics, methylprednisolone pulses followed by prednisone 1 mg/kg per day and cyclosporine A. Four patients received Intravenous Immunoglobulin G and two Etoposide (VP-16), only one patient received plasmapheresis. Both patients with sJIA where treated with Anakinra and one also required etanercept and tocilizumab. The mean follow up was 33±19 months (range 18-51 months) and there were no deaths. Two patients had relapses (one with SLE and one with sJIA), none of these had received Etoposide. Fifty percent required blood cell and platelet transfusion and two patients had plasma and fibrinogen transfusions also.
Conclusions SLE and sJIA are the rheumatic disease most commonly associated with SAM. Fever, hypertriglyceridemia, hyperferritinemia, hepatic cytolysis, lactate dehydrogenase elevation and high C-reactive protein are the most common manifestations in MAS. Triggering factors were infections and rheumatic disease activity in equal proportions. Aggressive treatment from the beginning with Etoposide could prevent relapses.
Disclosure of Interest None Declared