Thrombocytopenia (low platelet count)
Medically reviewed on April 3, 2018.
Thrombocytopenia is a condition in which you have a low blood platelet count. Platelets (thrombocytes) are colorless blood cells that help blood clot. Platelets stop bleeding by clumping and forming plugs in blood vessel injuries.
Thrombocytopenia often occurs as a result of a separate disorder, such as leukemia or an immune system problem. Or it can be a side effect of taking certain medications. It affects both children and adults.
Thrombocytopenia may be mild and cause few signs or symptoms. In rare cases, the number of platelets may be so low that dangerous internal bleeding occurs. Treatment options are available.
Thrombocytopenia signs and symptoms may include:
- Easy or excessive bruising (purpura)
- Superficial bleeding into the skin that appears as a rash of pinpoint-sized reddish-purple spots (petechiae), usually on the lower legs
- Prolonged bleeding from cuts
- Bleeding from your gums or nose
- Blood in urine or stools
- Unusually heavy menstrual flows
- Enlarged spleen
When to see a doctor
Make an appointment with your doctor if you have any warning signs that worry you.
Bleeding that won't stop is a medical emergency. Seek immediate help if you experience bleeding that can't be controlled by the usual first-aid techniques, such as applying pressure to the area.
Petechiae may look like a rash and usually appear in clusters. Here they appear on a leg (A) and on an abdomen (B).
If for any reason your blood platelet count falls below normal, the condition is called thrombocytopenia. Normally, you have anywhere from 150,000 to 450,000 platelets per microliter of circulating blood. Because each platelet lives only about 10 days, your body continually renews your platelet supply by producing new platelets in your bone marrow.
Thrombocytopenia can be inherited or it may be caused by a number of medications or conditions. Whatever the cause, circulating platelets are reduced by one or more of the following processes: trapping of platelets in the spleen, decreased platelet production or increased destruction of platelets.
The spleen is a small organ about the size of your fist located just below your rib cage on the left side of your abdomen. Normally, your spleen works to fight infection and filter unwanted material from your blood. An enlarged spleen — which can be caused by a number of disorders — may harbor too many platelets, causing a decrease in the number of platelets in circulation.
Decreased production of platelets
Platelets are produced in your bone marrow. If production is low, you may develop thrombocytopenia. Factors that can decrease platelet production include:
- Some types of anemia
- Viral infections, such as hepatitis C or HIV
- Chemotherapy drugs
- Heavy alcohol consumption
Increased breakdown of platelets
Some conditions can cause your body to use up or destroy platelets more rapidly than they're produced. This leads to a shortage of platelets in your bloodstream. Examples of such conditions include:
- Pregnancy. Thrombocytopenia caused by pregnancy is usually mild and improves soon after childbirth.
- Immune thrombocytopenia. This type is caused by autoimmune diseases, such as lupus and rheumatoid arthritis. The body's immune system mistakenly attacks and destroys platelets. If the exact cause of this condition isn't known, it's called idiopathic thrombocytopenic purpura. This type more often affects children.
- Bacteria in the blood. Severe bacterial infections involving the blood (bacteremia) may lead to destruction of platelets.
- Thrombotic thrombocytopenic purpura. This is a rare condition that occurs when small blood clots suddenly form throughout your body, using up large numbers of platelets.
- Hemolytic uremic syndrome. This rare disorder causes a sharp drop in platelets, destruction of red blood cells and impairment of kidney function. Sometimes it can occur in association with a bacterial Escherichia coli (E. coli) infection, such as may be acquired from eating raw or undercooked meat.
- Medications. Certain medications can reduce the number of platelets in your blood. Sometimes a drug confuses the immune system and causes it to destroy platelets. Examples include heparin, quinine, sulfa-containing antibiotics and anticonvulsants.
The spleen is a small organ normally about the size of your fist. A number of conditions, including liver disease and some cancers, can cause your spleen to become enlarged.
Dangerous internal bleeding can occur when your platelet count falls below 10,000 platelets per microliter. Though rare, severe thrombocytopenia can cause bleeding into the brain, which can be fatal.
Your doctor may use the following tests and procedures to determine whether you have thrombocytopenia:
- Blood test. A complete blood count determines the number of blood cells, including platelets, in a sample of your blood. In adults, normal platelet count is 150,000 to 450,000 platelets per microliter of blood. If the complete blood count finds you have fewer than 150,000 platelets, you have thrombocytopenia.
- Physical exam, including a complete medical history. Your doctor will look for signs of bleeding under your skin and feel your abdomen to see if your spleen is enlarged. He or she will also ask you about illnesses you've had and the types of medications and supplements you've recently taken.
Your doctor may suggest that you undergo other tests and procedures to determine the cause of your condition, depending on your signs and symptoms.
People with mild thrombocytopenia may not need treatment. For example, they may not have symptoms or the condition clears up on its own.
Some people develop severe or long-term (chronic) thrombocytopenia. Depending on what's causing your low platelet count, treatments may include:
Treating the underlying cause of thrombocytopenia. If your doctor can identify a condition or a medication that's causing your thrombocytopenia, addressing that cause may clear up your thrombocytopenia
For example, if you have heparin-induced thrombocytopenia, your doctor will direct you to stop using heparin and prescribe a different blood-thinning drug. Your thrombocytopenia may persist for a week or more despite stopping all heparin therapy.
- Blood or platelet transfusions. If your platelet level becomes too low, your doctor can replace lost blood with transfusions of packed red blood cells or platelets.
- Medications. If your condition is related to an immune system problem, your doctor may prescribe drugs to boost your platelet count. The first-choice drug may be a corticosteroid. If that doesn't work, he or she may try stronger medications to suppress your immune system.
- Surgery. If other treatment options don't help, your doctor may recommend surgery to remove your spleen (splenectomy).
- Plasma exchange. Thrombotic thrombocytopenic purpura can result in a medical emergency requiring plasma exchange.
Lifestyle and home remedies
If you have thrombocytopenia, try to:
- Avoid activities that could cause injury. Ask your doctor which activities are safe for you. Contact sports, such as boxing, martial arts and football, carry a high risk of injury.
- Drink alcohol in moderation, if at all. Alcohol slows the production of platelets in your body. Ask your doctor whether it's OK for you to drink alcohol.
- Use caution with over-the-counter medications. Over-the-counter pain medications, such as aspirin and ibuprofen (Advil, Motrin IB, others) can impair platelet function.
Preparing for an appointment
Start by seeing your primary care doctor if you have any signs or symptoms that worry you. Most cases of thrombocytopenia can be managed by your doctor. In certain situations, he or she may recommend that you see a specialist in blood diseases (hematologist).
Because appointments can be brief, and because there's often a lot of ground to cover, it's a good idea to be well-prepared for your appointment. Here's some information to help you get ready and what to expect from your doctor.
What you can do
- Be aware of any pre-appointment restrictions. At the time you make the appointment, be sure to ask if there's anything you need to do in advance, such as restrict your diet.
- List the warning signs you've noticed, such as any unusual bruising or bleeding or any rashes. Include any signs that may seem unrelated to the reason for which you scheduled the appointment.
- List key personal information, including any recent illnesses or medical procedures such as a blood transfusion, major stresses or recent life changes.
- Make a list of all medications, vitamins and supplements that you're taking.
- Take along a family member or friend. It can be difficult to remember all the information provided during an appointment. The person who accompanies you may remember something that you forgot or missed.
- List questions to ask your doctor. List your questions from most important to least important, in case time runs out.
For thrombocytopenia, some questions you may want to ask include:
- How many platelets do I have in my blood?
- Is my platelet count dangerously low?
- What is causing my thrombocytopenia?
- Do I need more tests?
- Is my condition likely temporary or chronic?
- What are my treatment options?
- What will happen if I do nothing?
- What are the possible side effects of the treatments you're suggesting?
- Are there any restrictions that I need to follow?
- Is there a generic alternative to the medicine you're prescribing?
- Do you have any brochures or other printed material that I can take with me?
- What websites do you recommend?