Analysis of 7 cases of macrophage activation syndrome secondary to systemic juvenile idiopathic arthritis in infants and toddlers / 中华风湿病学杂志

ABSTRACT

Objective:To investigate the clinical features, diagnosis and treatment of systemic juvenile idiopathic arthritis (SJIA) complicated with macrophage activation syndrome (MAS).Methods:From January 1st, 2018 to January 1st, 2020, 7 cases of SJIA-MAS were diagnosed. Their clinical and laboratory data were collected and summarized.Results:In these 7 cases, 2 were males and 5 were females, the ratio of male to female was 2∶5. The age range was 11 months to 2 years old. The course of disease was 14 to 32 days. The clinical manifestations included fever and rash in 7 without arthritis; hepatomegaly, splenomegaly and lymphadenopathy in 7; hematological involvement in 7; nervous system involvement in 2; digestive system involvement in 7; respiratory system involvement in 7; cardiovascular involvement in 3. White blood cell was decreased in 1 case, platelet was decreased in 1 case and hemoglobin was decreased in 7 cases. Ferritin, triglyceride, alanine transaminas and aspartate aminotransferase were increased in 7 cases, fibrinogen was significantly decreased in 7 cases, and direct bilirubin was increased in 4 cases. IL-2R was significantly increased. Hemophagocytosis was observed in bone marrow of 4 cases. Cerebrospinal fluid protein was 2 005 mg/L in 1 case. All the 7 cases were tested for exon genes, and no pathogenic mutation was found. All of the 7 cases showed lung lesions in chest CT scan. Multiple demyelinating lesions were found in 1 case by head magnetic resonance imaging. One case was treated with high-dose intravenous methylprednisolone combined with IL-6 receptor antagonist(tocilizumab). The other 6 cases were treated with high-dose intravenous methylprednisolone combined with cyclosporine A (CsA). Two cases were treated with Janus kinases inhibitor(tofacitinib). After treatment, 7 cases got relieved, no death, no recurrence oocurred during the follow-up.Conclusion:Acute onset, multiple organ involvement and no joint inflammation are prominent in MAS of infants and toddlers. High fever, proressive reduction of blood cells and increase of SF are significant in SJIA-MAS. High dose glucocorticoid combined with CsA can benefit in most cases, and some severe cases need to be treated with biological agents.