Background Macrophage activation syndrome (MAS) is a potentially fatal complication of Still's disease (SD). The use of biologic disease-modifying antirheumatic drugs (bDMARDs) has significantly improved the prognosis in SD pts, although most recent reports on MAS linked to use of bDMARDs in SD patients raise certain concern.
Objectives To share the experience from the use of bDMARD for management of MAS, induced by other bDMARDs in an adult patient with SD.
Methods Description of a case of successful rituximab therapy for MAS, induced by tocilizumab in an adult SD patient.
Results In a patient Sh.,18 yo, the onset of SD occurred in December 2008y (at the age of 14 y.o.), manifesting with fever 39°C, arthralgia, lymphadenopathy, hepatosplenomegaly, neutrocytosis, maculopapular rash, ESR up to 40 mm/h, CRP 48 mg/L. Prednisone (50 mg/day) was discontinued shortly due to emergence of multiple duodenal ulcers (EFGDS), which resulted in increasing CRP up to 154 mg/L, anemia (nv-89 g/L), neutrocytosis up to 14,7x109, elevated ALT and AST >120 EU/L, LDH 735 U/L, and ferritine >12000 μg/L. This condition progressed to tonic-clonic seizures and coma, leucopenia (4,5x109), and thrombocytopenia (33x109). MAS was documented. GCs were re-administered (prednisone 50 mg/day, methylpred pulse-therapy), sandimmun was also commenced at 200 mg/day dose. By 2013 y. the dose of prednisone was down-titrated to 2,5 mg/day and of sandimmun - to 100 mg/day. At this dose level a relapse of fever 38,5° C, arthralgia, pharyngalgia and rash on the forearms occurred. The dose of prednisone was up-titrated to 20 mg/day, but arthralgia and ubnormal lab parameters of active disease persisted (ferritine, CRP, ESR), necessitating administration of tocilizumab (8 mg/kg). But second infusion of tocilizumab caused severe adverse reaction (dyspnea, drop of BP, nausea, dizziness) with MAS reoccurrence (fever 39,5° C, thrombocytopenia, anemia, elevated liver enzymes, ferritine, hypofibrinogenemia, hypertriglyceridemia), necessitating up-titration of methylpred dose up to 40 mg/day, pulse therapy with methylpred and dexamethasone, IVIG (2.5 g/kg total dose), SAMe. Associated pneumonia was successfully cured with antibiotics (CT verified). Rituximab 1000 mg was administered i/v by drop infusion, and repeated after 6 mo. Currently the patient does not voice any specific complaints, her lab parameters are constantly normal (remission), the methylpred dose was down-titrated to 4 mg/day.
Conclusions Presented case, on one side, raises the appropriateness of updating the summary of product characteristics&directions for tocilizumab use in package circular/prescribing info, and on the other side, confirms the usefulness of rituximab for refractory Still's disease, complicated with MAS.
Disclosure of Interest None declared