Primary polycythaemia in childhood and adolescence.

Four adolescents with polycythaemia are described where symptoms typical of the disease had already existed in childhood. Three patients fulfilled the criteria of a polycythaemia vera. In one female patient the possibility of familial erythrocytosis is discussed. Polycythaemia vera mononuclear cells formed erythroid colonies in cultures in the absence of erythropoietin. The patients were phlebotomized to maintain haematocrit readings of 40 to 45%. No case has yet progressed to myeloid metaplasia or acute leukaemia.