Symptoms of Erythrocytosis
The symptoms of erythrocytosis depend on how elevated the red blood cell count becomes and whether complications arise. While erythrocytosis may be asymptomatic in its early stages, high red cell levels can cause blood to thicken, reducing oxygen flow and increasing the risk of clotting.
Common Symptoms
Headaches – Due to increased blood viscosity and reduced oxygen to the brain
Dizziness or light-headedness, especially during exertion
Blurred or double vision
Flushed skin, particularly on the face
Reddened eyes
High blood pressure
Fatigue, which may seem paradoxical despite the high oxygen-carrying capacity
Shortness of breath, especially on exertion or when lying flat
These symptoms may develop gradually or appear suddenly in cases of rapid red cell production.
Serious Symptoms and Complications
As blood thickens, the risk of clots increases. Patients may present with:
Chest pain, which may signal a heart attack
Leg swelling or pain, possibly due to deep vein thrombosis (DVT)
Stroke-like symptoms, including slurred speech, weakness, or vision changes
Bleeding or bruising, in conditions like polycythaemia vera, due to platelet abnormalities
Clot-related complications are the most dangerous consequences of erythrocytosis and require immediate medical attention.
Symptoms in Children
Though rare, erythrocytosis in children may be linked to congenital heart disease or inherited mutations. Symptoms may include:
Cyanosis (bluish skin)
Poor growth
Tiring easily
Clubbing of fingers or toes
Symptoms of Erythrocytosis In South Africa
In South Africa, many patients with chronic lung conditions may develop secondary erythrocytosis without realising it. Symptoms such as breathlessness, fatigue, or dizziness may be wrongly attributed to ageing or poor fitness. Routine screening in high-risk groups could lead to earlier diagnosis.
Public education on the signs of abnormal blood counts and routine health checks can play a vital role, particularly in regions where access to specialist care is limited.
Recognising the symptoms of erythrocytosis early can prevent serious complications and guide timely intervention before a blood clot or stroke occurs.
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