Sustained remission of platelet counts following monoclonal anti-CD20 antibody therapy in two cases of idiopathic autoimmune thrombocytopenia and neutropenia

Idiopathic autoimmune thrombocytopenia and neutropenia (ITN) is a primary h aemocytopenic disorder clinically characterised by recurrent mucocutaneous bleeding episodes and infections. Unlike in simple idiopathic thrombocytope nic purpura. the platelet deficiency of ITN tends to be chronic and difficu lt to treat. We describe two patients with ITN who obtained sustained remis sion of their platelet counts after therapy with the chimeric monoclonal an ti-CD20 antibody Rituximab. In one of two cases, Rituximab also induced pro longed normalisation of the neutrophil count and disappearance of auto-anti bodies. Our observations indicate that disturbed B-cell function plays a ce ntral role in the pathogenesis of ITN. Anti-CD20 antibody therapy seems to constitute a safe and efficient alternative to corticosteroids for the mana gement of ITN patients with chronic thrombocytopenia.