Hyper-reactive malarial splenomegaly in a European patient after residencein Africa.

Introduction. - Hyper-reactive malarial splenomegaly (HMS) syndrome related to abnormal immunologic response to repeated malarial infections is unusua l in European expatriates. Exegesis. - We report the case of a 72-year-old white male patient who had been residing in the Congo and developed a typical clinical features of hyp eractive malarial syndrome characterized by massive splenomegaly wit hypers plenism, high titers of malarial IgM antibodies, IgM macroglonulinemia, liv er and medullary lymphocytic proliferation, and a clinical and immunologica l response to long-trm chloroquine therapy. Conclusion. - Criteria for the diagnosis of hyper-reactive malarial splenom egaly are useful. However, making a distinction from malignant lymphoprolif erative disorders is difficult, as a sustained response to chloroquine is r equired. Therefore, chloroquine appears to have a regulatory effect on the immune system. (C) 1999 Elsevier, Paris.