Polycythemia: Definition, Symptoms, Causes, Diagnosis, Treatment, and Overview

Also known as erythrocytosis, it means a high concentration of red blood cells.

The word polycythemia means the presence of” many cells in the blood. “

This makes the blood thicker and therefore less able to move through the blood vessels and organs. Many of the symptoms of polycythemia are due to this slow blood flow.

Polycythemia is a blood condition in which the bone marrow produces excess blood cells, mainly red blood cells and other cells such as platelets and white blood cells.

The extra cells cause thickening of the blood, increasing the risk of blood clotting, and this, in turn, can be a cause of strokes, heart attacks, and other complications.

While the exact cause of polycythemia is not known, genetic changes are believed to be related to its development.

Congenital polycythemia, known as polycythemia vera, develops slowly and is usually seen in older adults. It is rare in young adults and children.


Although it is the result of genetic mutations or changes in particular genes, these genetic changes are acquired during an individual’s lifetime. They are generally not passed from parents to children.

Polycythemia is not a very common condition, and about one in 200,000 people are diagnosed with the disease each year.

In secondary polycythemia, long-term oxygen deprivation, such as chronic smoking or long periods at high altitudes, causes increased blood cell production and thickening of the blood.

This form of polycythemia often resolves once the cause of oxygen deprivation is addressed.

In all cases of polycythemia, treatment with regular blood draws or drugs to reduce the number of blood cells is generally effective, although there is no cure for the condition.

While polycythemia is rare, it can usually be treated, and the symptoms are generally mild; serious complications, such as a heart attack or stroke, can occur if left untreated.

Immediate medical attention should be sought for any sudden heart attack symptoms or strokes, such as sudden numbness, weakness, confusion, vision problems, or chest pain.

Polycythemia can also cause less severe symptoms, such as shortness of breath when lying down or excessive bleeding.

Immediate medical attention if these symptoms persist is critical, as early diagnosis and intervention can prevent more severe symptoms.

Symptoms of polycythemia

Polycythemia may not cause any symptoms. It is often discovered only if a hemoglobin test or red blood cell count is done.

Some people experience symptoms that come on gradually.

A baby with polycythemia may be eating poorly and have low blood sugar, and have trouble breathing.

It is important to note that the problem is not a great concern to babies.

It often does not require treatment and resolves within a few days.

Very rarely, polycythemia causes severe problems in babies, such as seizures due to poor circulation in the brain.

In the early stages of polycythemia, symptoms can be mild and include:

  • Headaches.
  • Blurry vision.
  • Red skin, particularly flushing of the face, hands, and feet.
  • Fatigue.
  • High blood pressure
  • Dizziness
  • Discomfort in the abdomen.
  • Periods of confusion.
  • Bleeding problems, such as nosebleeds and bruising.
  • The appearance of conditions such as gout can cause joint pain, stiffness, and swelling.
  • Itchy skin, especially after a bath or shower, results from white blood cells (levels of which can also be high) releasing the chemical histamine.
  • Alteration of the senses.

In more severe cases, the slow blood flow associated with polycythemia can also cause blood clots. These can be serious because they can put you at risk for life-threatening problems, such as:

  • Heart attacks.
  • Pulmonary embolisms (a blockage in the blood vessel that carries blood from the heart to the lungs).
  • Bruises
  • In some cases, a blood clot, known as a deep vein thrombosis, can form in the leg before moving to another part of the body.

Signs of deep vein thrombosis or a pulmonary embolism may include:

  • Pain, swelling, redness, and tenderness in one of your legs.
  • Sharp pain in the affected area.
  • Warm skin in the size of ​​the clot.
  • Difficulty breathing.
  • Chest or upper back pain.
  • Cough accompanied by blood.
  • Dizziness and fainting

If you experience any of the above symptoms, you should see a doctor immediately; it could be symptoms of a heart attack or stroke.

Causes of polycythemia

Polycythemia can be divided into several different types, depending on the condition’s underlying cause. In some cases, an underlying cause cannot be identified.

Absolute polycythemia

“Absolute polycythemia” is where your body makes too many red blood cells. There are two main types:

Primary polycythemia

In primary polycythemia, there is a problem in the cells produced by the bone marrow that turn into red blood cells; The most common type is polycythemia vera.

Problems with the bone marrow cause polycythemia vera.

Although the exact cause of polycythemia vera is unknown, researchers have found that a specific gene mutation is associated with almost everyone with this condition.

A fault causes polycythemia vera in the JAK2 gene, a rare condition that generally causes cells in the bone marrow to make too many red blood cells.

The bone marrow is in the center of most bones and typically makes all of the red blood cells and platelets, and most of the white blood cells.

When this process is disrupted, cell production is no longer orderly, and conditions such as polycythemia can arise.

The affected bone marrow cells can also become a change in other cells found in the blood.

This means that people with polycythemia vera may also have abnormally high numbers of platelets (thrombocytosis) and white blood cells (leukocytosis).

Polycythemia vera is a rare condition that generally affects men.

Most cases develop later in life, with the average age of diagnosis being 60 years. The condition is rarely seen in people under the age of 40, although it can also affect babies.

Secondary polycythemia

Although the exact cause of polycythemia vera is unknown, several factors seem to lead to secondary polycythemia.

Secondary polycythemia is when an underlying condition causes more erythropoietin to be produced.

High content of red blood cells accumulates in response to the low concentration of oxygen in the air.

Because there is less oxygen in the blood, the body tries to overcome the lack by making more red blood cells.

However, it doesn’t stop and keeps producing them until there are too many.

The bone marrow can also be overstimulated by testosterone replacement therapy.

This is a hormone produced by the kidneys that stimulate the cells of the bone marrow to produce red blood cells.

It can also occur in people with kidney problems, such as kidney tumors and cysts or narrowing the arteries that supply blood to the kidneys.

Chronic lung diseases and excessive cigarette use are generally associated with increased carbon monoxide in the blood and can also lead to higher levels of red blood cells and hemoglobin.

Low oxygen levels in the blood (hypoxia) due to congenital heart disease also appear to be a factor in the development of polycythemia.

Most people who live at high altitudes do not appear to have secondary polycythemia.

The condition is practically absent in some mountain regions. When it occurs, it is thought that other environmental factors may contribute to the appearance of this disease.

Polycythemia in babies usually occurs because the baby receives more than the average amount of blood from the placenta during delivery.

It can also result from the mother living at a high altitude or if the baby had a placenta that was not working optimally.

Apparent polycythemia

“Apparent polycythemia” is where your red blood cell count is average, but you have a reduced amount of a fluid called plasma in your blood, which makes it thicker.

The condition is often caused by being overweight, smoking excessively, drinking large amounts of alcohol, or taking certain medications, such as diuretics.

A similar condition that is sometimes called “relative polycythemia” can also occur due to dehydration.

Apparent polycythemia may improve if the underlying cause is identified and managed. Quitting smoking or reducing your alcohol consumption, for example, can help.

Diagnosis of polycythemia

To diagnose polycythemia, a doctor will begin by looking at the patient’s health history and performing a physical exam.

The doctor will check for evidence of low brain or lung blood flow by asking about symptoms such as headache, weakness, tinnitus (ringing or ringing in the ears), or the appearance of vision problems.

The doctor will also look for physical signs such as increased blood volume, enlarged veins, and a reddish complexion.

If the skin becomes red or itchy, especially after taking a hot bath, it may indicate a diagnosis of polycythemia.

The doctor can also check for a history of smoking or alcohol abuse or a family history of kidney disease.

A review of blood pressure values, patient weight (obesity), lack of oxygen (cyanosis), heart murmurs, or audible whistling sounds or murmurs may also be performed on a physical exam. The vascular artery or canal is called murmurs.

Diagnostic tests will likely include oxygen saturation measurements and a complete blood count.

Uric acid levels can also rise and should be checked.

For some people, the doctor may suggest a bone marrow test.

Additional tests may be recommended to determine whether it is polycythemia vera or secondary polycythemia.

The doctor may also order tests to detect genetic mutations associated with the condition.

A blood test can be done to look for a mutation in a protein called Jak-2.

The diagnosis may include an ultrasound of your abdomen to check for kidney problems.

Treatment of polycythemia

Treatment will vary based on the person’s age, sex, medical condition, symptoms, and blood test results.

Treatment for polycythemia aims to prevent symptoms and complications (such as blood clots) and treat any underlying causes.

Venesection or phlebotomy

Venesection or phlebotomy is the easiest and fastest way to reduce the number of red blood cells.

This procedure may be recommended if the patient has polycythemia vera, a history of blood clots, or symptoms that suggest that their blood is too thick.

Phlebotomy removes tiny amounts of blood and used to be the most common type of treatment for polycythemia vera.

When phlebotomy is used, blood is drawn in 300ml to 500ml every few days at first, tapering off every few weeks and then every few months.

The goal of treatment will be to keep the hemoglobin level in the blood within the low to normal range.

Often, the blood collection process can be stopped for months to see if the hemoglobin level remains in the required range.

For the elderly or people with the disease of the blood vessels of the heart or brain, generally less blood is taken, that is, only 200 ml to 300 ml twice a week.

Once a person’s hemoglobin levels return to normal, treatment is likely done at monthly medical appointments.

Medicines to reduce the production of red blood cells

In cases of polycythemia vera, medications may be prescribed to decrease the production of red blood cells.

If the blood has an elevated white blood cell and platelet count and a high red blood cell content, the doctor may prescribe a medicine that reduces the production of blood cells by the bone marrow, such as radioactive phosphorus.

This drug has an 80 to 90 percent success rate.

Its main advantage is that people need fewer follow-up visits when the disease is under control.

Just one treatment a year can be enough to control the disease.

A reported disadvantage of radioactive phosphorus therapy is that it can turn normal white blood cells into leukemia cells. For this reason, it is rarely used today.

Other medications can be used daily to lower both white blood cell and platelet count.

There are many different medications available, and the specialist will consider the patient’s age and health status, response to venesection, and red blood cell count.

These medications include:


Hydroxycarbamide is generally well tolerated, but pregnant women or women trying to conceive should not take it.


Interferon can be taken during pregnancy, but it can cause unpleasant side effects, such as hair loss and flu-like symptoms.

Medicines to prevent blood clots

To reduce the risk of blood clots, treatment with low-dose acetylsalicylic acid is recommended for most people with polycythemia unless there is a reason not to take it.

When you have polycythemia vera, daily low-dose aspirin tablets may be prescribed to help prevent blood clots and reduce the risk of serious complications.

Your doctor may also recommend low-dose aspirin treatment if you have apparent or secondary polycythemia and another condition that affects your blood vessels, such as coronary heart disease or cerebrovascular disease.

Treatments to prevent other conditions

Complications such as high uric acid levels in the blood and itchy skin can be treated with allopurinol or antihistamines.

In rare cases, the spleen can become significantly enlarged. Your doctor may recommend surgical removal (splenectomy).

Anyone who has had a splenectomy should get vaccinated to prevent future infections.

If the disorder appears to be causing significant problems in a baby, up to several ounces of blood can be drawn and replaced with intravenous fluid.

This procedure generally dilutes the circulating red blood cells until they return to an average level.

Unfortunately, there is no way to prevent polycythemia vera. However, you can reduce your risk of secondary polycythemia by not smoking or drinking excessively.

Some people may also need treatment for any other symptoms or complications of polycythemia they have or for any underlying cause of the condition.

Changes in lifestyle

In addition to improving some cases of apparent polycythemia, making healthy lifestyle changes can also reduce the risk of potentially serious blood clots for people with all types of polycythemia.

Having polycythemia means that you are already at high risk for blood clots, and being overweight or smoking only increases this risk.

In general, these tips should be followed:

  • Reach a healthy weight.
  • Prevent cardiovascular disease.
  • Control blood pressure levels.
  • Give up smoking.


The outlook for polycythemia largely depends on the underlying cause.

Many cases are mild and may not lead to further complications. However, some cases, particularly polycythemia vera, can be more severe and require long-term treatment.

If well controlled, polycythemia should not affect life expectancy, and the patient should be able to lead an everyday life.

However, people with polycythemia vera may have a slightly lower than average life expectancy due to the increased risk of problems, such as heart attacks and strokes.

Sometimes, polycythemia vera can also cause scarring of the bone marrow (myelofibrosis), which can eventually lead to too few blood cells.

The condition can develop into a type of cancer called acute myeloid leukemia in some rare cases.

If you have polycythemia, it is essential to monitor regularly, take the medications your doctor prescribes, and watch for signs of possible blood clots to help reduce your risk of serious complications.