Thrombocytopenia
Low platelet count - thrombocytopeniaThrombocytopenia means there is an abnormally low amount of platelets. Platelets are parts of the blood that help blood to clot. This condition is sometimes associated with abnormal bleeding.
Causes
Thrombocytopenia is often divided into 3 major causes of low platelets:
- Not enough platelets are made in the bone marrow
- Increased removal of platelets in the bloodstream
- Increased trapping of platelets in the spleen or liver
Your bone marrow may not make enough platelets if you have any of the following conditions:
-
Aplastic anemia (disorder in which the bone marrow does not make enough blood cells)
Aplastic anemia
Aplastic anemia is a condition in which the bone marrow does not make enough blood cells. Bone marrow is the soft, tissue in the center of bones tha...
Read Article Now Book Mark Article - Cancer in the bone marrow, such as leukemia
Leukemia
Leukemia is a type of blood cancer that begins in the bone marrow. Bone marrow is the soft tissue in the center of the bones, where blood cells are ...
Read Article Now Book Mark Article - Cirrhosis (liver scarring)
-
Folate deficiency
Folate deficiency
Folate deficiency means you have a lower-than-normal amount of folic acid, a type of vitamin B, in your blood.
Read Article Now Book Mark Article - Infections in the bone marrow (very rare)
-
Myelodysplastic syndrome (bone marrow does not make enough blood cells or makes defective cells)
Myelodysplastic syndrome
Myelodysplastic syndrome is a group of disorders in which the blood cells produced in the bone marrow do not mature into healthy cells. This leaves ...
Read Article Now Book Mark Article - Vitamin B12 deficiency
Use of certain medicines may also lead to a low production of platelets in the bone marrow. The most common example is chemotherapy treatment for cancer.
The following health situations cause a low number of platelets:
- Disorder in which the proteins that control blood clotting become over active, most often during a serious illness (disseminated intravascular coagulation - DIC)
Disseminated intravascular coagulation ...
Disseminated intravascular coagulation (DIC) is a serious disorder in which the proteins that control blood clotting become overactive.
Read Article Now Book Mark Article - Drug-induced low platelet count
- Enlarged spleen
- Disorder in which the immune system destroys platelets (immune thrombocytopenic purpura - ITP)
Immune thrombocytopenic purpura - ITP
Immune thrombocytopenic purpura (ITP) is a bleeding disorder in which the immune system destroys platelets, which are necessary for normal blood clot...
Read Article Now Book Mark Article - Disorder that causes blood clots to form in small blood vessels, causing a low platelet count (thrombotic thrombocytopenic purpura - TTP)
Thrombotic thrombocytopenic purpura - T...
Thrombotic thrombocytopenic purpura (TTP) is a blood disorder in which platelet clumps form in small blood vessels. This leads to a low platelet cou...
Read Article Now Book Mark Article
Symptoms
You may not have any symptoms. Or you may have general symptoms, such as:
- Bleeding in the mouth and gums
-
Bruising
Bruising
A bruise is an area of skin discoloration. A bruise occurs when small blood vessels break and leak their contents into the soft tissue beneath the s...
Read Article Now Book Mark Article -
Nosebleeds
Nosebleeds
A nosebleed is loss of blood from the tissue lining the nose. Bleeding most often occurs from one nostril only.
Read Article Now Book Mark Article -
Rash
Rash
Rashes involve changes in the color, feeling or texture of your skin.
Read Article Now Book Mark Article
Other symptoms depend on the cause.
Exams and Tests
Your health care provider will perform a physical exam and ask about your medical history and symptoms. The following tests may be done:
-
Complete blood count (CBC)
Complete blood count
A complete blood count (CBC) test measures the following:The number of white blood cells (WBC count)The number of red blood cells (RBC count)The numb...
Read Article Now Book Mark Article - Blood clotting tests: partial thromboplastin time (PTT) and prothrombin time (PT)
Partial thromboplastin time
Partial thromboplastin time (PTT) is a blood test that looks at how long it takes for blood to clot. It can help tell if you have a bleeding problem...
Read Article Now Book Mark ArticleProthrombin time
Prothrombin time (PT) is a blood test that measures the time it takes for the liquid portion (plasma) of your blood to clot. It measures the functio...
Read Article Now Book Mark Article
Other tests that may help diagnose this condition include bone marrow aspiration or biopsy.
Bone marrow aspiration
Bone marrow is the soft tissue inside bones that helps form blood cells. It is found in the hollow part of most bones. Bone marrow aspiration is th...
Read Article Now Book Mark ArticleBiopsy
A bone marrow biopsy is the removal of marrow from inside one of your bones. Bone marrow is the soft tissue inside bones that helps form blood cells...
Read Article Now Book Mark ArticleTreatment
Treatment depends on the cause of the condition. In some cases, a transfusion of platelets may be required to stop or prevent bleeding.
Outlook (Prognosis)
The outcome depends on the disorder causing the low platelet counts.
Possible Complications
Severe bleeding (hemorrhage) is the main complication. Bleeding may occur in the brain or gastrointestinal tract.
When to Contact a Medical Professional
Contact your provider if you experience unexplained bleeding or bruising.
Prevention
Prevention depends on the specific cause.
References
Abrams CS. Thrombocytopenia. In: Goldman L, Cooney KA, eds. Goldman-Cecil Medicine. 27th ed. Philadelphia, PA: Elsevier; 2024:chap 158.
Branchford BR, Samelson-Jones BJ, Flood VH. Platelet and blood vessel disorders. In: Kliegman RM, St. Geme JW, Blum NJ, eds. Nelson Textbook of Pediatrics. 22nd ed. Philadelphia, PA: Elsevier; 2025:chap 533.
Warkentin TE. Thrombocytopenia caused by hypersplenism, platelet destruction, or surgery/hemodilution. In: Hoffman R, Benz EJ, Silberstein LE, et al, eds. Hematology: Basic Principles and Practice. 8th ed. Philadelphia, PA: Elsevier; 2023:chap 130.
Zeller MP, Ning S, Arnold DM, Gabe C. Diseases of platelet number: immune thrombocytopenia, neonatal alloimmune thrombocytopenia, and posttransfusion purpura. In: Hoffman R, Benz EJ, Silberstein LE, et al, eds. Hematology: Basic Principles and Practice. 8th ed. Philadelphia, PA: Elsevier; 2023:chap 129.
Review Date: 3/31/2024
Reviewed By: Todd Gersten, MD, Hematology/Oncology, Florida Cancer Specialists & Research Institute, Wellington, FL. Review provided by VeriMed Healthcare Network. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.