ABSTRACT

Hemophagocytic lymphohistiocytosis is a clinical syndrome characterized by hyperinflammation. There is uncontrolled activation and proliferation of T cells and excessive activation of macrophages. It may develop subsequent to a number of recognised genetic mutations (primary) or in association with infection, malignancy, autoinflammation or metabolic conditions (secondary). Macrophage activation syndrome is a form of hemophagocytic lymphohistiocytosis seen in rheumatic diseases, most commonly in systemic onset juvenile idiopathic arthritis. It is characterized by cytopenia, organ dysfunction and coagulopathy. Recognition of HLH can be challenging because it may mimic the clinical features of the underlying disease or be confused with an infectious complication. A high index of suspicion is necessary to diagnose. The aim of treatment is the control of hyperinflammation and removal of the stimulant.