Peripheral-T-cell lymphoma with hemophagocytic histiocytosis localised to the bone marrow associated with inappropriate secretion of antidiuretic hormone.

A patient with high fever, loss of weight and profound pancytopenia is reported. Peripheral T-cell lymphoma with hemophagocytosis was diagnosed. Bone marrow was the only localisation of the lymphoma. At presentation there were (i) a coagulopathy consistent with hemophagocytic histiocytosis (ii) the features of the syndrome of inappropriate antidiuretic hormone secretion (SIADH). These different abnormalities disappeared after chemotherapy and reappeared during each of the 2 periods of disease progression. The patient died 6 months after diagnosis without ever achieving complete remission. As far as we are aware this is the first case report of T-cell lymphoma with hemophagocytic syndrome localised to the bone marrow and associated with SIADH.