Platelet Disorders Causes and Risk Factors

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Your body needs platelets to form blood clots. Blood clots help you prevent too much blood loss after an injury.

You may be born with a platelet disorder or develop one later in life. Platelet disorders occur when:

• Your body makes too many platelets
• Your body makes too few platelets
• Your platelets are used up or destroyed faster than they can be replaced
• You have enough platelets but they don't work properly

There are many causes of platelet disorders. For example, thrombocythemia is most often caused by changes in certain genes . The changes cause your bone marrow to make too many platelets.

If your bone marrow is damaged, it may make too few platelets, which causes thrombocytopenia. A low platelet count can also happen if your immune system destroys your platelets by mistake. Conditions other than immune system issues, such as liver disease, sepsis, and pregnancy and certain medicines, such as heparin and chemotherapy drugs, may also cause thrombocytopenia. There are also rare inherited conditions that can cause thrombocytopenia and platelet dysfunction.

You may have an increased risk of a platelet disorder due to your age, family history and genetics , lifestyle habits, medicines, other medical conditions, or sex.

Age

You may be at a higher risk of a platelet disorder depending on your age.

• Immune thrombocytopenic purpura (ITP) can occur at any age. Adolescents and adults are more likely to have chronic ITP (lasting longer than 12 months) than children. Newborns may have thrombocytopenia at birth if their mother has ITP, but the thrombocytopenia will go away.
• Thrombotic thrombocytopenic purpura (TTP) that is caused by another medical condition or a medicine is more common in adults between 18 and 50 years old. Inherited /congenital TTP usually affects babies and children.

Family history and genetics

Some types of platelet disorders can be inherited. "Inherited" means your parents pass the gene for the condition to you. Therefore, you may have a higher risk of a platelet disorder if you have a family member with the condition.

Lifestyle habits

Lifestyle habits can raise your risk of a low platelet count.

• Alcohol can damage your bone marrow and cause it to make fewer platelets than normal.
• Certain foods or herbs may raise your risk of low platelet counts. These include English walnuts and sesame seeds.
• Using tobacco products may cause your body to make fewer platelets than normal.

Medicines

Certain medicines may increase your risk of developing a platelet disorder, especially if you have a family history or other risk factors.

• Blood thinners, such as heparin
• Certain antibiotics, such as ampicillin and vancomycin
• Chemotherapy or radiation for cancer treatment
• Immunosuppressant medicines, such as tacrolimus and cyclosporine, that may be used after an organ transplant
• Over-the-counter pain medicines, such as aspirin and ibuprofen
• Quinine
• Seizure medicines, such as carbamazepine and valproic acid
• Stomach acid (H2) blockers, such as cimetidine and ranitidine
• Vaccines, including measles-mumps-rubella (MMR) and, less commonly, influenza and human papillomavirus

Medical conditions

Conditions that can raise your risk of high platelet disorders include:

• Autoimmune disorders, such as thyroid disease, lupus, sarcoidosis, and scleroderma
• Blood and bone marrow diseases, such as aplastic anemia, disseminated intravascular coagulation, and leukemia
• Hemolysis
• Inflammation or viral infections, such as HIV and SARS-CoV-2
• Kidney or liver disease
• Serious bleeding
• Spleen that is larger than normal
• Vitamin B12, folate, or iron deficiency

Sex

Many platelet disorders are more common in women across most age groups. The risk of a low platelet count increases during pregnancy. It is often not serious and does not require treatment. In some cases, it is caused by a serious pregnancy complication.

When a blood vessel is injured, the damaged cells in the vessel wall send out chemical signals. These signals cause clots that slow or stop bleeding.

If you have a high platelet count, blood clots may form in your blood vessels even when there is no injury. These clots can block blood flow through your body and prevent your organs from getting enough blood. If you have a low platelet count, your blood may not clot normally and you may have trouble stopping bleeding. This can make you lose a lot of blood even from a small injury.

Bleeding disorders and blood clotting disorders also affect how blood clots form in your body. Learn more about blood clots, what causes them, and how they can affect your health in this NIH article.

Currently, there is no way to prevent a platelet disorder that is caused by your genes. If you plan to become pregnant and know that your child is at risk of having a platelet disorder, you can talk to a genetic counselor. They can answer questions about the risk and explain what choices are available to you.

Many platelet disorders are caused by other medical conditions or medicines. These cannot be prevented or avoided completely.

You can take the following steps to lower your risk of a platelet disorder.

• Adopt healthy lifestyle habits. Healthy habits, such as quitting smoking and not drinking too much alcohol, may help you prevent a low platelet count.
• Avoid certain medicines. If you have a history of platelet disorders caused by a medicine (such as one listed above), your provider may ask you to avoid these medicines.