Overview & Definition
Erythrocytosis (Polycythemia) is a condition marked by an abnormally high concentration of red blood cells and hemoglobin, causing hyperviscosity (thickened blood) and increased risk of blood clots.
Types & Classification
- Primary Erythrocytosis (Polycythemia Vera)
- Secondary Erythrocytosis (Hypoxia-driven)
- Relative Erythrocytosis (Dehydration / Stress)
- Congenital High Affinity Hemoglobinopathy
Underlying Causes & Risk Factors
- JAK2 V617F gene mutation in bone marrow stem cells
- Chronic hypoxia (Smoking, COPD, Sleep Apnea)
- High altitude living
- Erythropoietin-secreting tumors (Kidney/Liver)
Common Symptoms & Warning Signs
Diagnostic Evaluation
Accurate diagnosis requires comprehensive laboratory investigation under expert hematological supervision:
- 🔍 CBC showing Hemoglobin > 16.5 g/dL (Men) or > 16.0 g/dL (Women)
- 🔍 Serum Erythropoietin (EPO) Level Test
- 🔍 JAK2 Exon 14 & Exon 12 Mutation Analysis
- 🔍 Bone Marrow Biopsy examining erythroid hyperplasia
Treatment Options & Clinical Management
- 💊 Therapeutic Phlebotomy (Venesection) – scheduled blood removal to maintain Hematocrit target <45%.
- 💊 Low-Dose Aspirin (81–100 mg daily) – antiplatelet therapy to reduce thrombotic risk in Polycythemia Vera (unless contraindicated).
- 💊 Cytoreductive Therapy – Hydroxyurea or Pegylated Interferon Alfa-2a for high-risk Polycythemia Vera.
- 💊 Targeted JAK2 Inhibitor (Ruxolitinib) – indicated for Polycythemia Vera patients resistant or intolerant to Hydroxyurea.
- 💊 Management of Secondary Causes – treatment of chronic hypoxemia, obstructive sleep apnea, or smoking cessation.
Frequently Asked Questions
Early symptoms include facial flushing or redness (plethora), intense itching after a warm shower or bath (aquagenic pruritus), headaches, dizziness, visual disturbances, ringing in ears, and burning pain in fingers or toes (erythromelalgia).
Diagnosis requires verifying elevated hemoglobin (>16.5 g/dL in men, >16.0 g/dL in women) or hematocrit, testing serum Erythropoietin (EPO) levels, screening for JAK2 exon 14 (V617F) and exon 12 gene mutations, and performing a bone marrow biopsy to assess erythroid hyperplasia.