[Polycytemia vera in an 11-year old girl].

The case of an 11 year old girl with three line type of polycythaemia vera, with 4 cm splenomegaly and a plethoric complexion is presented. Peripheral blood values were as follows: RBC: 7.75 x 10(12)/l, Hb: 18.8 g/l, WBC: 15.2 x 10(9)/l, platelets: 920 x 10(9)/l. Serum erythropoietin level: < 1 mU/ml. In vitro, erythroid colonies developed from the bone marrow in the absence of added erythropoetin. For three years the haematocrit value has been controlled by regular venesections. Since extreme thrombocytosis developed, the treatment was continued with interferon alpha. Different treatment protocols are discussed.