Macrophage activation syndrome at the onset of glucocorticoid-resistant systemic lupus erythematosus: a case report.

INTRODUCTION

Macrophage activation syndrome (MAS) is a life-threatening hyperinflammatory state mediated by uncontrolled cytokine storm and haemophagocytosis. Although rarely reported, MAS might occur in systemic lupus erythematosus (SLE), notably as an inaugural manifestation. Glucocorticoids (GCs) are the cornerstone of SLE therapy. However, in some cases high doses of GCs are required to achieve remission (i.e. glucocorticoid-resistance), leading to significant side effects.

CASE REPORT: A 28-year-old Romani male was admitted to our hospital for polyarthralgia, polyserositis and fatigability. The patient had high-grade fever, jaundice and generalized lymphadenopathy. Laboratory tests revealed severe mixed hemolytic autoimmune anemia, leukopenia, hepatocytolysis, coagulation abnormalities, hypertriglyceridemia, biological inflammatory syndrome, hyperferritinemia and persistent proteinuria of nephritic pattern. Imaging studies showed pleuropericardial effusion, hepatosplenomegaly and polysynovitis. Additional blood tests revealed hypocomplementemia and positive ANA, anti-dsDNA and anti-Sm antibodies. Haemophagocytosis was not identified either on bone marrow or axillary lymph node biopsy specimens. However, SLE-associated MAS seemed to fit this set-up. High-dose corticotherapy (6.5 g methylprednisolone followed by prednisone, 1.5 mg/kg/day after discharge) and intravenous cyclophosphamide were necessary to induce and sustain remission.

CONCLUSION

MAS is a potentially severe manifestation that should be considered at SLE onset whenever high fever and elevated serum levels of aspartate aminotransferase, lactate dehydrogenase, C-reactive protein, ferritin and procalcitonin are noted. Early diagnosis and prompt treatment lead to remission in two thirds of cases. Glucocorticoid-resistance leads to the use of high-dose corticotherapy or immunosuppressive agents that could elicit serious side effects. New insights into the molecular mechanisms of glucocorticoid-resistance are needed in order to conceive more adequate GC-therapies.