Abstract
Tocilizumab (TCZ) is the first FDA- approved treatment for systemic juvenile idiopathic arthritis (sJIA). We report 3 cases of cytopenias in children with sJIA treated with TCZ. Two of the children who developed significant cytopenias shortly after initiation of TCZ had a history of macrophage activation syndrome. We raise the possibility that patients with a tendency towards MAS have an increased risk of developing cytopenias when treated with tocilizumab.
Highlights
Systemic juvenile idiopathic arthritis is a subtype of chronic childhood arthritis of unknown etiology that is characterized by spiking fever, rash, generalized lymphadenopathy, hepatosplenomegaly, and serositis [1]
We report 3 cases of cytopenias in children with Systemic juvenile idiopathic arthritis (sJIA) treated with TCZ necessitating a dose reduction or discontinuation of the drug
Case 2, in addition to thrombocytopenia, developed anemia, hypofibrinogenemia, and hyperferritinemia, which could be consistent with macrophage activation syndrome (MAS), these lab abnormalities resolved without any intervention
Summary
Systemic juvenile idiopathic arthritis (sJIA) is a subtype of chronic childhood arthritis of unknown etiology that is characterized by spiking fever, rash, generalized lymphadenopathy, hepatosplenomegaly, and serositis [1]. About 7% of sJIA patients develop macrophage activation syndrome (MAS), which is due to excessive activation of macrophages and T cells leading to a profound inflammatory reaction. Prior studies of TCZ have not reported the development of significant cytopenias requiring medication discontinuance [3,4,5]. We report 3 cases of cytopenias in children with sJIA treated with TCZ necessitating a dose reduction or discontinuation of the drug. Case 1 A 6 year-old Caucasian girl with a 6 month history of sJIA was started on twice monthly TCZ therapy (12 mg/kg/ dose) after failed treatment with methotrexate, adalimumab, and rilonacept due to persistent arthritis and inability to wean steroids. After 5 transfusions of tocilizumab over a twelve week period, her absolute neutrophil count (ANC) dropped from 13,900 to 800 cells/μL. Methotrexate was resumed and her TCZ dose was subsequently decreased to 8 mg/kg/dose and administered every three weeks without further incident over a 10 month follow-up period
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
