What is thrombocytopenia?
Thrombocytopenia is the medical term for a low platelet count. Platelets are tiny blood cells that clump together to help stop bleeding when a blood vessel is injured. Most healthy adults have between 150,000 and 450,000 platelets per microliter of blood. When platelet levels fall below that range, the blood may not clot as well as it should. Mild drops might not cause any problems, but severe drops can lead to heavy bleeding after an injury or during surgery.
At Penn Medicine, hematologists with expertise in bleeding disorder care diagnose and treat thrombocytopenia and the many conditions that can cause it. They work closely with specialists across multiple fields to identify the reason for a low platelet count and recommend care based on your symptoms, platelet levels, overall health, and treatment goals.
How a low platelet count can affect you
Symptoms of low platelets can be mild, and some people have thrombocytopenia without noticing any symptoms at all. Often, one of the first signs is a cut or nosebleed that takes longer than usual to stop bleeding. You may also notice:
- Tiny red or purple dots on the skin (petechiae)
- Easy or excessive bruising (purpura)
- Bleeding gums
- Heavy menstrual bleeding (menorrhagia)
- Blood in urine (hematuria)
- Blood in stool
What causes thrombocytopenia?
Thrombocytopenia develops when something affects your body’s ability to make, maintain, or circulate platelets. This can happen for many reasons and affects both children and adults.
Your bone marrow normally makes new platelets to replace those your body naturally uses each day. Certain conditions and treatments can slow platelet production, causing your platelet count to fall.
Possible causes include:
- Bone marrow disorders
- Blood cancers, like leukemia
- Viral infections, including hepatitis C and HIV
- Vitamin B12 or folate deficiency
- Cancer treatments, like chemotherapy or radiation therapy
- Some medications, including certain antibiotics
- Heavy alcohol use
Sometimes your body destroys platelets faster than it can replace them. This can happen when the immune system mistakenly attacks healthy platelets or when another condition causes platelets to be used more quickly than normal.
Possible causes include:
- Immune thrombocytopenia (ITP)
- Autoimmune diseases, like lupus
- Certain medications
- Severe infections
- Pregnancy-related conditions
- Disseminated intravascular coagulation (DIC)
- Thrombotic thrombocytopenic purpura (TTP)
An enlarged spleen can hold onto more platelets than usual, leaving fewer circulating in your bloodstream. Conditions that enlarge the spleen, including liver disease and some blood disorders, can lead to this type of thrombocytopenia.
Finding the cause of a low platelet count
Thrombocytopenia is often discovered during a routine complete blood count (CBC) test before symptoms develop. To find the cause of a low platelet count, your provider will review your medical history, current medications, and symptoms. They’ll also perform a physical exam to look for signs of bleeding, check for bruising or petechiae on your skin, and examine your spleen, liver, and lymph nodes.
In addition to a CBC, your provider may recommend a peripheral blood smear to examine your platelets under a microscope. Depending on your symptoms and medical history, you may also need additional blood tests to look for infections, vitamin deficiencies, autoimmune conditions, or other health concerns that can affect platelet levels. In some cases, a bone marrow biopsy may be recommended if the cause remains unclear or a bone marrow disorder is suspected.
Treatment options for low platelet count
Not everyone with thrombocytopenia needs treatment. If your platelet count is only mildly low and isn’t causing symptoms, your provider may monitor it over time. When treatment is needed, the goal is to address the root cause and lower your risk of bleeding. Depending on what’s causing your low platelet count, that might mean changing a medication, treating an underlying medical condition, or using medicines that help your body make more platelets or calm an overactive immune response.
For more serious or urgent bleeding risks, treatment may include platelet transfusions, corticosteroid medications, intravenous immunoglobulin infusions, or, in some cases, surgery to remove the spleen.
Care led by specialists who understand blood disorders
When you’re diagnosed with thrombocytopenia, you want answers and a plan you can trust. Penn Medicine’s bleeding disorders specialists have deep experience diagnosing and managing low platelet counts, from mild cases that just need monitoring to complex or immune-related conditions like ITP.
Our hematologists work closely with you to find the cause behind your symptoms and build a treatment plan that fits your life. If your condition needs ongoing care, you’ll have a team that gets to know you and your medical history and is there to support you over time.