MACROPHAGE ACTIVATION SYNDROME AND RHEUMATIC DISEASE IN CHILDHOOD - AREPORT OF 4 NEW CASES

A macrophage activation syndrome (MAS) developed in four children with chronic rheumatic diseases. The presentation included fever, hepatic and splenic enlargement, profound depression of blood counts, lowering of ESR, elevation of SGOT/PT and hypofibrinogenemia. The most charact eristic sign of MAS was the presence in the bone marrow aspirate of we ll differentiated macrophages showing active haemophagocytosis with ha ematopoietic elements in their cytoplasm. Activation of the macrophage was also illustrated by high levels of monokines in the serum of 2 pa tients. This immuno-hematological process of unknown etiology can be t riggered by ubiquitous events such as infections and treatment with an ti-inflammatory drugs. It is a potentially lethal complication which s hould be diagnosed rapidly, since administration of high-dose steroids with discontinuation of potentially toxic drugs can induce remission. Cyclosporin A was effective in two patients and may be of value in th e management of the macrophage-activation syndrome. Its efficacy suppo rts the central involvement of a T-cell dysfunction. It must be borne in mind that children with rheumatic diseases, especially the systemic form of juvenile chronic arthritis, are highly vulnerable to life-thr eatening macrophage activation, which appears to be more frequent than previously recognized Very careful monitoring of apparently ''innocen t '' drugs and intercurrent viral infections is thus required