PURE RED CELL APLASIA: Designated by the acronym PRCA or the term erythroblastopenia, pure red cell aplasia is characterised by severe anaemia with reticulocytopenia. It may occur in acute form induced by infectious agents, following drug toxicity or transplantation of allogeneic haematopoietic cells, associated with autoimmune haemolytic anaemia. The chronic form is rarely constitutional but can be acquired and is usually associated with blood or idiopathic diseases. IMMUNOLOGICAL INHIBITION OF ERYTHROPOIESIS: Among the mechanisms responsible for PRCA is immunological erythropoiesis inhibition. This may be of lymphocyte T cell origin or due to the presence of antibodies in the patient's serum. Although observations of PRCA with presence of neutralising antierythropoietin antibodies in patient's serum have multiplied over the past 5 years, they still remain extremely rare. From a therapeutic point of view, they require withdrawal of epoetin and often the administration of immunosuppressors and transfusion for symptomatic treatment. GROWTH FACTORS: The role of growth factors in restoring aplastic anaemia appears to be only partial, at random and temporary.