Blood Platelets and Thrombocytopenia Facts and Effects
What Is Thrombocytopenia?
Blood platelets play a vital role in blood clotting and wound healing. The body has to regulate their numbers very carefully. If someone has too many platelets, blood clots may form where they don’t belong, obstructing blood flow. If a person has too few platelets, bleeding from injuries may increase.
Platelets are also known as thrombocytes. Thrombocytopenia is a condition in which the blood has a low platelet count. Blood platelets are made in the bone marrow, along with red and white blood cells. Thrombocytopenia can develop if the bone marrow doesn't make enough platelets or if the platelets are destroyed after they have formed. Thrombocytopenia is often a mild or moderately severe disease, but sometimes it's a serious condition. The treatment depends on the severity of the disorder.
Platelets and Their Manufacture
There are two types of bone marrow—red and yellow. Red bone marrow makes platelets and blood cells in a process called hematopoiesis. Yellow bone marrow stores fat instead. Large cells in the red bone marrow called megakaryocytes release cell fragments, which become the platelets.
Platelets are much smaller than red blood cells and white blood cells and have a flat, disk shape until they are activated. They were given their name by earlier scientists, who thought that they looked like tiny plates. They normally live for seven to ten days.
Functions of Platelets
The endothelium is the internal lining of the blood vessels. When the endothelium is damaged, chemicals which attract and activate platelets are exposed. As platelets are activated, they change their shape. They become spherical and produce tentacle-like extensions. The activated platelets stick to each other and to the wound, forming a platelet plug that stops the bleeding from the wound.
The activated platelets and proteins in the blood then work together to create a blood clot through a series of chemical reactions. The final reaction is the conversion of a dissolved blood protein called fibrinogen into solid fibrin threads. The threads form a mesh over the wounded area, trapping blood and platelets in a blood clot.
Anyone with symptoms that may suggest the presence of thrombocytopenia should visit a doctor for a diagnosis and treatment. People with questions about the disorder should also visit their doctor. The information below is intended for general interest.
The Platelet Count
According to the National Institutes of Health (NIH), human blood normally contains between 150,000 to 450,000 platelets in each microliter of the blood. If someone’s platelet count is below 150,000 per microliter of blood, he or she is said to suffer from thrombocytopenia. A mild case of thrombocytopenia may not produce any symptoms. When the platelet count is reduced to around 50,000 platelets per microliter of blood, the person may experience minor bleeding problems. A platelet count of below 20,000 platelets per microliter of blood may cause serious symptoms.
If the bone marrow doesn’t make enough platelets or if platelets are destroyed once they are made, thrombocytopenia may result. Excessive storage of blood or platelets in the spleen can also cause the disorder. Some specific factors that can lower the platelet level in the blood are described below.
Role of the Spleen
The spleen is located on the left side of the upper abdomen under the rib cage. The organ helps to improve the condition of the blood in a variety of ways. For example, it filters out old and damaged red blood cells. It also contains white blood cells that fight bacteria and viruses.
In addition, the spleen contains a reserve supply of blood and platelets, which can be helpful in an emergency. The spleen normally stores up to one third of the platelets in the body. If the spleen is enlarged, it may store too many platelets and cause a low blood platelet count.
Platelet Manufacture Problems
A range of factors can interfere with the manufacture of platelets in the bone marrow.
- Someone with thrombocytopenia may have inherited a genetic problem that prevents him or her from making enough platelets.
- Alcohol and poisonous chemicals like arsenic, benzene, and some pesticides can slow platelet production.
- Some types of diuretics and epilepsy drugs can also interfere with platelet manufacture.
- In a disease called aplastic anemia, the bone marrow doesn’t make enough blood cells or platelets.
- A deficiency in vitamin B12 and folic acid can reduce platelet manufacture.
- Some types of cancer and cancer treatments may damage bone marrow and hinder it from making blood platelets.
- An HIV, parvovirus, or hepatitis C virus infection can decrease platelet production.
- Certain viruses can lower the platelet count. These include the Epstein-Barr virus, which causes mononucleosis and other health problems, the viruses that cause chickenpox, rubella (German measles), and mumps, and the virus that causes dengue fever.
- Some bacterial infections in the blood also lower the platelet count.
Platelet Destruction or Hindrance
In some cases, platelets are formed normally but are then destroyed.
- The use of heparin, quinine, sulfa antibiotics, and some epilepsy drugs can lead to platelet destruction.
- Aspirin, ibuprofen, and some antihistamines stop platelets from working normally, which can increase bleeding.
- Platelets may be destroyed in rheumatoid arthritis and lupus.
- Autoimmune diseases are conditions in which a person’s body attacks its own cells. If these cells are platelets, thrombocytopenia can result.
- The body destroys platelets in a disorder called idiopathic thrombocytopenic purpura (ITP). The condition is also known as immune thrombocytopenic purpura. “Purpura” means “bruises", referring to the bleeding under the skin that appears during this disease. The term "idiopathic" means that the exact cause of the disorder is unknown. It is known that the immune system attacks and destroys platelets, however.
- Some women develop mild thrombocytopenia close to the end of their pregnancy, for an unknown reason.
- Thrombocytopenia may develop in a fetus if the mother suffers from certain infections, including rubella and toxoplasma. It may also occur when the mother's body mistakenly makes antibodies that cross the placenta and destroy the baby's platelets.
Purpura is a skin rash that consists of purple or red spots on the skin. The spots are areas where bleeding is occurring under the skin. If the spots are less than three millimetres in diameter, they are known as petechiae. In this case the rash may be known as a petechial rash.
Possible Symptoms of Thrombocytopenia
Internal or external bleeding is the main symptom of thrombocytopenia. It's important to note that the symptoms below may be caused by a condition other than a low platelet count. They may be the result of a relatively minor problem, but it's still important to pinpoint their cause.
A person with thrombocytopenia may have a rash made of red or purple spots on the skin, or purpura. The person may find that they bleed a long time often even a small cut. Their gums may also bleed after they brush their teeth or after they visit a dentist. The gums may bleed even without any mouth irritation. (Bleeding gums may have a different cause from thrombocytopenia, however.) In addition, the person may have bad nosebleeds. In women, menstrual blood flow may be heavy.
There may be blood in the affected person's urine or stool or bleeding from the rectum, which may indicate internal bleeding. In very severe thrombocytopenia, there may be bleeding from the brain or heavy digestive tract bleeding. These are serious symptoms. Many cases of thrombocytopenia are less severe, however.
Make sure that you see your doctor or dentist if you have any signs of increased bleeding. There are several possible causes for abnormal bleeding. A diagnosis and treatment by a health professional is needed.
A doctor's visit is required in order to solve and deal with a problem of increased bleeding. If you are found to have a mild case of thrombocytopenia you may not need treatment, but this decision needs to be made by your doctor.
More serious cases of thrombocytopenia will likely require some form of treatment. In some cases, if the cause of the problem is treated, the disorder disappears. Medication may need to be changed or prescribed and infections will need to be treated.
Drugs may be given to suppress the immune system or corticosteroids may be prescribed to slow platelet destruction. Blood or platelet transfusion or spleen removal (splenectomy) may be necessary in some cases.
A doctor will know about the appropriate treatments for a particular individual. They will also known about any new discoveries related to the condition.
A Healthy Lifestyle and Some Precautions
It's often possible to live well with a low platelet count if certain precautions are taken. If you have thrombocytopenia there are things that you can do to help yourself, even if you are receiving medical treatment.
- Avoid chemicals and medications which are known to hinder platelet production or destroy platelets, if possible.
- Eat nutritious foods and exercise regularly to boost your immune system and try to avoid infections.
- Tell your doctor about any supplements or herbal medicines that you are taking, since some of them may affect the blood platelet level.
- Try to avoid injuries as much as possible. Ask your doctor whether participating in contact sports or sports with a high risk of injury, such as skiing, are appropriate activities for you.
- Wear protective gloves, helmets, or clothing when performing any activity that may cause an injury.
- Consider getting vaccines for illnesses known to lower platelet levels, if vaccines are available and your doctor recommends that you get them.
- Consider wearing a medic alert bracelet or ID.
By following your doctor's advice and asking him or her questions when necessary, you should be able to deal with thrombocytopenia in the best way possible.
This content is accurate and true to the best of the author’s knowledge and does not substitute for diagnosis, prognosis, treatment, prescription, and/or dietary advice from a licensed health professional. Drugs, supplements, and natural remedies may have dangerous side effects. If pregnant or nursing, consult with a qualified provider on an individual basis. Seek immediate help if you are experiencing a medical emergency.
Questions & Answers
Can you survive with a platelet count of 5,000?
According to the Merck Manual Professional, a platelet count of less than 5,000 per microlitre is linked to "severe, possibly life-threatening spontaneous bleeding". A person with a count of 5,000 platelets per microlitre would need to be under intense medical care.Helpful 7
© 2010 Linda Crampton