[The chronic Philadelphia chromosome-negative myeloproliferative syndrome II. Clinical findings, diagnostics and treatment].

Polycythaemia vera (PV) and essential thrombocytosis (ET) are clinically characterised by non-specific neurologic symptoms, peripheral circulatory disturbances (acrocyanosis, wounds, erythromelalgia) or abdominal symptoms. The treatment of PV includes phlebotomy, antiaggregation and cytoreduction. In ET, the primary treatment is also low-dose aspirin except for patients presenting with a haemorrhagic diathesis. Hydroxyurea may be associated with an increased risk of acute leukaemia or myelodysplasia. Therefore alpha-interferon and anagrelide should be considered in younger patients. Early cytoreductive therapy is advocated in patients with idiopathic myelofibrosis (IMF) to inhibit further progression of bone marrow fibrosis and further expansion of myeloid metaplasia in the spleen and liver. Treatment with androgens (danazol) and glucocorticoids may improve severe anaemia and thrombocytopenia. In younger patients, allogeneic bone marrow transplantation should be considered.