Reactive haemophagocytic syndrome (RHS) is a disorder characterized by
systemic proliferation of nonmalignant histiocytes occurring most com
monly in patients with pre-existing immunological abnormalities or neo
plasms. Patients, particularly those with immunosuppression, often hav
e a rapidly progressive fatal course. Treatment is directed at the und
erlyng disorder. In the absence of identifiable cause, the therapy is
less satisfactory. We report here three cases of RHS successfully trea
ted with high-dose gamma-globulin therapy. Two of the three patients w
ere immunocompromised and the third occurred during pregnancy. The imp
rovement occurred within 24-72h and all patients recovered. High-dose
i.v. gamma-globulin therapy may be beneficial in RHS.