Canis ISSN: 2398-2942

Polycythemia: secondary

Contributor(s): Kyle Braund

Introduction

  • Cause: myeloproliferative disease , pathological or physiological response.
  • Signs: bleeding or often neurological.
  • Diagnosis: hematology, erythropoietin assay.
  • Treatment: manage underlying cause if physiological or chemotherapy if neoplastic.
  • Prognosis: reasonable; good if can eliminate underlying problem.

Pathogenesis

Etiology

  • Polycythemia can be classified as:
    • Relative, ie normal red cell mass but PCV Hematology: packed cell volume increased due to reduced plasma volume.
    • Absolute, ie increased PCV Hematology: packed cell volume , red cell mass and [hemoglobin]:
      • Primary, iepolycythemia rubra vera Polycythemia: primary a rare myeloproliferative disorder (abnormal proliferation of erythroid precursors in bone marrow that occurs independent of erythropoietin).
    • Secondary (erythropoietin-mediated erythropoiesis): physiological, pathological.

Specific

  • Physiological:
    • Chronic pulmonary disease.
    • Right to left shunts.
    • High altitudes.

Pathophysiology

  • In normal animal:
    • Erythropoietin (produced by the kidneys) stimulates proliferation of red cell precursors in bone marrow → increased production of red blood cells.
    • Erythropoietin produced in response to tissue hypoxia (physiological) → renal oxygen sensors → increased production and secretion of erythropoietin → increased red cell mass.
  • Pathological polycythemia:
    • Production of erythropoietin-like substance by tumor which continually stimulates red cell production.
    • Functional renal neoplasia producing erythropoietin free from negative feedback mechanisms.
    • Autonomous clonal expansion of red cell precursors in bone marrow (myeloproliferative disease).

Timecourse

  • Weeks to months.

Diagnosis

This article is available in full to registered subscribers

Sign up now to purchase a 30 day trial, or Login

Treatment

This article is available in full to registered subscribers

Sign up now to purchase a 30 day trial, or Login

Outcomes

This article is available in full to registered subscribers

Sign up now to purchase a 30 day trial, or Login

Further Reading

Publications

Refereed papers

  • Recent references from PubMed and VetMedResource.
  • Crow S E et al (1995) Concurrent renal adenocarcinoma and polycythemia in a dog. JAAHA 31 (1), 29-33 PubMed.
  • Quesnel A D & Kruth S A (1992) Polycythemia vera and glomerulonephritis in a dog. Can Vet J 33 (10), 671-672 PubMed.
  • Campbell K L (1990) Diagnosis and management of polycythemia in dogs. Comp Cont Ed Pract Vet 12 (4), 543-550 VetMedResource.
  • Waters D J & Preuter J C (1986) Secondary polycythemia associated with renal disease in the dog 2 case reports and review of the literature. JAAHA 24 (1), 109-114 VetMedResource
  • McGrath C J, Krawiec D R & Johnston S D (1982) Canine polycythemia vera, a review of diagnostic features. Vet Med 77 (4), 611-613 VetMedResource.

Other sources of information

  • Hasler A H, Giger U (2000)Polycythemia.In:Textbook of Veterinary Internal Medicine. 5th edn. Eds: Ettinger S J & Feldman E C. W B Saunders, Philadelphia. pp 203-206.


ADDED