×
MedSchool: Ace Your OSCEsThe Medical Company
 
 
 
 
 
GET - On the App Store
View
Test Findings
 
 

Erythrocytosis

 
Bookmark

Overview

Erythrocytosis is the presence of increased circulating red blood cells.
The terms erythrocytosis and polycythaemia are often used interchangeably, though polycythaemia is less specific as it suggests pathology in multiple cell lineages.
  • Look For

  • Increased red cell count (RCC)
  • Elevated haemoglobin (Hb)
  • Elevated haematocrit (HCT) / packed cell volume (PCV)
  • Interpretation

  • Elevated Hb / PCV with elevated RCC - absolute erythrocytosisBone marrow pathology (primary) or excess erythropoietin (secondary)
  • Elevated Hb / PCV with normal RCC - relative erythrocytosisContraction of plasma volume
  • Causes of Erythrocytosis

  • Primary

  • Primary familial erythrocytosis (EPO receptor mutation)
  • Polycythaemia vera (JAK2 mutation)
  • Secondary

  • Chronic hypoxia - smoking, chronic lung disease, obstructive sleep apnoea, high altitude
  • Renal hypoxia - renal artery stenosis, polycystic kidney disease, post renal transplant
  • Drugs - testosterone, anabolic steroids, erythropoietin
  • Paraneoplastic syndrome (EPO-producing tumour)
  • Congenital - haemoglobinopathies, other mutations
  • Idiopathic
  • Relative

  • Severe dehydration
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Want more info like this?
  • Your electronic clinical medicine handbook
  • Guides to help pass your exams
  • Tools every medical student needs
  • Quick diagrams to have the answers, fast
  • Quizzes to test your knowledge
Sign Up Now