Pseudopolycythaemia

Pseudopolycythaemia is a medical condition characterized by an apparent increase in the red blood cell concentration in the blood, which can be misleading if not properly diagnosed. Unlike true polycythemia, where there is an actual increase in red blood cell mass, pseudopolycythaemia involves a relative increase in red blood cell concentration due to a decrease in the volume of plasma in the blood. This condition is also known as stress polycythemia, Gaisböck's syndrome, or spurious polycythemia.

Causes

Pseudopolycythaemia can be caused by a variety of factors that lead to a reduction in plasma volume. These include:

• Dehydration: Lack of adequate water intake or excessive loss of fluids can lead to a concentrated blood volume.
• Smoking: Nicotine and other substances in cigarettes can cause a reduction in plasma volume.
• Obesity: Increased blood viscosity and reduced plasma volume are often seen in obese individuals.
• High blood pressure: Hypertension can sometimes contribute to the condition by affecting blood volume and viscosity.

Symptoms

The symptoms of pseudopolycythaemia can mimic those of true polycythemia and may include:

• Headache
• Dizziness
• Fatigue
• Redness of the skin (erythema)
• Itching (pruritus), especially after a hot bath

Diagnosis

Diagnosing pseudopolycythaemia involves distinguishing it from true polycythemia. Key diagnostic tests include:

• Complete blood count (CBC): To check the levels of red blood cells, white blood cells, and platelets.
• Hematocrit (Hct) and Hemoglobin (Hb) levels: Elevated levels may indicate an increased concentration of red blood cells.
• Blood volume studies: To differentiate between true polycythemia (increased red blood cell mass) and pseudopolycythaemia (normal red blood cell mass with decreased plasma volume).

Treatment

Treatment of pseudopolycythaemia focuses on addressing the underlying cause of the reduced plasma volume. This may include:

• Increasing hydration: Encouraging the intake of more fluids to increase plasma volume.
• Lifestyle changes: Such as quitting smoking and losing weight.
• Managing underlying conditions: Such as controlling high blood pressure.

Prognosis

The prognosis for individuals with pseudopolycythaemia is generally good, especially when the underlying cause can be identified and treated effectively. Without treatment, the condition can lead to increased blood viscosity and an elevated risk of thrombosis or blood clots.

See Also

• Polycythemia vera
• Anemia
• Blood donation