+ Site Statistics
References:
54,258,434
Abstracts:
29,560,870
PMIDs:
28,072,757
+ Search Articles
+ Subscribe to Site Feeds
Most Shared
PDF Full Text
+ PDF Full Text
Request PDF Full Text
+ Follow Us
Follow on Facebook
Follow on Twitter
Follow on LinkedIn
+ Translate
+ Recently Requested

Treatment of Erythrocytosis in Polycythemia Vera with Dapson



Treatment of Erythrocytosis in Polycythemia Vera with Dapson



Blood 100(11): Abstract No 4941, November 16



Background: The correction of erythrocytosis in patients with polycythaemia vera (PV) is essential to prevent thrombotic complications. Usually this is done by repeated phlebotomies. However this strategy is hampered by an increased the risk of progressive marrow fibrosis. Alternatively, myelosuppressive therapy carries an increased risk of leukemic transformation. Recently we observed an immediate and sustained decrease of the hematocrit upon the administration of dapsone in a patient with PV poorly responding to repeated phlebotomies. To further assess the efficacy of dapsone on the erythrocytosis we treated 12 PV patients with dapsone 50-200 mg daily. They received no other treatment. Results: The median Hb decreased from 10,4 to 8,6 mmol/l, the Ht from 0,52 to 0,43. In all but three patients the hematocrit could be brought below the value of 0,45 in man or 0,42 in women. All patients developed laboratory symptoms of chronic hemolysis: the median reticulocyte count rose from 2,2 to 4,1%, the LDH from 175 to 280 u/l and the bilirubin from 11 to 22 mmol/l. The haptoglobin decreased from median 0,8 to 0,0 g/l. Therefore low grade chronic hemolysis induced by dapsone appears to be the mode of action in the treatment of erythrocytosis. Side effects were noted in 6 patients consisting of headache (n=3), fatigue (n=2) and dizziness (n=1). Only in one patient the side effect was reason to stop treatment. Side effects might be related to the methemoglobinaemia, the median concentration rose from 0,6 to 4,6% (range 2,1-12,1%). Four patients continue dapsone as single therapy for 11, 29, 34 and 117 months respectively with adequate control of their polycythemia vera. Two patients continued dapsone but additional therapy had to be given to control the erythrocytosis. In 6 patients the dapsone was stopped after a median of 7 months (range 1-17 months) because of : increasing splenomegaly (n=1), leuko- and trombocytosis (n=2), anaemia (n=1) and fatigue (n=1). Conclusion: Dapsone is a valuable drug in the control of erythrocytosis in polycythaemia vera. It is well tolerated and lacks the untoward side effects of prolonged phlebotomies or myelosuppressive therapy.

(PDF emailed within 1 workday: $29.90)

Accession: 035980403

Download citation: RISBibTeXText


Related references

Immunoglobulin levels in polycythemia vera, erythrocytosis, secondary polycythemia and myelofibrosis. Israel Journal of Medical Sciences 8(7): 925-931, 1972

Mechanisms of erythropoiesis differ between post-transplant erythrocytosis and polycythemia vera or familial polycythemia. Journal of the American Society of Nephrology 5(3): 1016, 1994

Polycythemia vera. V. Enhanced proliferation and phosphorylation due to vanadate are diminished in polycythemia vera erythroid progenitor cells: a possible defect of phosphatase activity in polycythemia vera. Blood 89(10): 3574-3581, 1997

No correlation of intensity of phlebotomy regimen with risk of thrombosis in polycythemia vera: evidence from European Collaboration on Low-Dose Aspirin in Polycythemia Vera and Cytoreductive Therapy in Polycythemia Vera clinical trials. Haematologica 102(6): E219-E221, 2017

Erythrocytosis due to presumed polycythemia vera. Cleveland Clinic Journal of Medicine 83(9): 648-653, 2018

Congenital erythrocytosis and polycythemia vera in childhood and adolescence. Klinische Padiatrie 216(3): 157-162, 2004

New criteria for differential diagnosis of polycythemia vera and erythrocytosis. Gematologiia i Transfuziologiia 37(9-10): 40-42, 1992

Diagnosing or ruling out polycythemia vera in patients with erythrocytosis. Clinical Advances in Hematology and Oncology 17(1): 24-27, 2019

Transformation of erythrocytosis associated with renal cyst to polycythemia vera. Haematologica 65(3): 343-348, 1980

A new criterion for the differential diagnosis of polycythemia vera and erythrocytosis. Gematologiya i Transfuziologiya 37(9-10): 40-42, 1992

Megakaryocytic colony formation in polycythemia vera and secondary erythrocytosis. British Journal of Haematology 69(4): 441-444, 1988

Quantification of PRV-1 mRNA distinguishes polycythemia vera from secondary erythrocytosis. Blood 102(10): 3569-3574, 2003

JAK2 exon 12 mutations in polycythemia vera or idiopathic erythrocytosis. Haematologica 92(12): 1717-1718, 2007

JAK2 Exon 12 Mutations in Polycythemia Vera and Idiopathic Erythrocytosis. Yearbook of Pathology and Laboratory Medicine 2008: 370-371, 2008

JAK2 exon 12 mutations in polycythemia vera and idiopathic erythrocytosis. New England Journal of Medicine 356(5): 459-468, 2007