Leucopenia Health Dictionary

A MALIGNANT disorder of PLASMA cells, derived from B-lymphocytes (see LYMPHOCYTE). In most patients the BONE MARROW is heavily in?ltrated with atypical, monoclonal plasma cells, which gradually replace the normal cell lines, inducing ANAEMIA, LEUCOPENIA, and THROMBOCYTOPENIA. Bone absorption occurs, producing di?use osteoporosis (see under BONE, DISORDERS OF). In some cases only part of the immunoglobulin molecule is produced by the tumour cells, appearing in the urine as Bence Jones PROTEINURIA.

The disease is rare under the age of 30, frequency increasing with age to peak between 60 and 70 years. There may be a long preclinical phase, sometimes as long as 25 years. When symptoms do occur, they tend to re?ect bone involvement, reduced immune function, renal failure, anaemia or hyperviscosity of the blood. Vertebral collapse is common, with nerve root pressure and reduced stature. The disease is eventually fatal, infection being a common cause of death. Local skeletal problems should be treated with RADIOTHERAPY, and the general disease with CHEMOTHERAPY

– chie?y the ALKYLATING AGENTS melphalan or cyclophosphamide. Red-blood-cell TRANSFUSION is usually required, together with plasmapheresis (see PLASMA EXCHANGE), and orthopaedic surgery may be necessary following fractures.... myelomatosis

A synthetic anticoagulant (see ANTICOAGULANTS). Given by mouth, it is used to prevent the formation of clots in the blood in rheumatic heart disease and atrial ?brillation (see HEART, DISEASES OF); as prophylaxis after insertion of a prosthetic heart valve; and as prophylaxis and treatment of venous thrombosis and pulmonary embolism. It is slower in action than WARFARIN, not achieving its full anticoagulant e?ect until up to 48 hours after the initial dose. The drug should be avoided in patients with renal or hepatic impairment, and whenever severe hypersensitivity reactions have previously occurred. Adverse effects include rashes, fever, LEUCOPENIA, AGRANULOCYTOSIS, diarrhoea and pink urine; breast feeding should be avoided.... phenindione