Dr. Alan D. Michelson, MD

Thrombocytopenia is a disorder where people have too few platelets. With too few platelets in the bloodstream, the blood is unable to properly clot. People with thrombocytopenia may experience prolonged external and internal bleeding. Large purple bruises (ecchymoses) and small red skin spots (petechiae) in the skin and mouth are common in those with thrombocytopenia. Other symptoms of the disorder include bleeding gums, blood in bodily fluids, and fatigue. Thrombocytopenia most often arises from a different condition or treatment, such as alcoholism, autoimmune disease, cancer treatments, viruses (such as Hepatitis C and HIV), bone marrow diseases (such as leukemia and aplastic anemia), enlarged spleen, and exposure to toxic chemicals. In rare cases, thrombocytopenia is inherited.

Thrombocytosis is a disorder where people have too high of a concentration of platelets. Excess platelets can cause blood to clot in the veins. Blood clots in the veins are particularly dangerous, as they can obstruct blood flow and cause heart attacks and strokes. Thrombocytosis has two forms:

• Thrombocythemia, also referred to as primary or essential thrombosis (ET), develops from irregular bone marrow cells that produce too many platelets. The cause of these bone marrow cells is unknown.
• Reactive thrombosis (RT), also referred to as secondary thrombosis, arises from a different condition such as cancer, anemia, spleen removal, or infection. It is most common in older adults, but can occur in people of all ages. Symptoms of reactive thrombosis may gradually develop over time and typically include bruising, gum bleeding, and blood clotting.
• Dysfunctional platelets are unable to perform the clotting function in the blood. People with dysfunctional platelets may have normal or low platelet counts. Causes of dysfunctional platelets include autoimmune disorders, hemolysis, infections, blood and bone marrow problems, and liver or kidney conditions.

If a doctor suspects a patient has a platelet disorder, a complete blood count (CBC) or platelet count test helps determine the concentration of platelets in a person's blood at a given time. Platelet disorders can be diagnosed by hematologists using advanced tests on platelet samples. Flow cytometry tests detect abnormalities by evaluating the characteristics of a platelet sample using targeted lasers and lights. Tests measuring prothrombin time (PT), or how long it takes for blood to clot, can also detect dysfunctional platelets. If platelets do not coagulate within a certain time frame, the patient most likely has dysfunctional platelets.

Treatments for low platelet counts include steroids like Prednisone, that can assist with platelet production. If a patient's low platelet count is caused by spleen problems, spleen removal (splenectomy) may be recommended. To treat the prolonged bleeding caused by thrombocytopenia, doctors frequently prescribe Dempressin, a hormone that promotes blood clotting. Antifibrinolytic medications such as tranexamic acid may also aid in the promotion of clotting and the prevention of bleeding. For patients with severe platelet disorders (either low platelet count and dysfunctional platelets), blood transfusions may be prescribed. Platelet blood transfusions deliver donated platelets to patients intravenously, replenishing the volume of functioning platelets.

Patients with high platelet counts are frequently prescribed a daily dose of over-the-counter medication aspirin. Platelet-lowering medications, such as hydroxyurea and Intron A, may reduce the likelihood of blood clot formation. Excess platelets may also be removed from the blood by a procedure called plateletpheresis or platelet reduction apheresis, where blood is drawn, circulated into a centrifuge that separates the blood components, and returned to the body with some platelets extracted. Plateletpheresis is a rare procedure reserved for patients who have severe clotting.

Patients can also modify their lifestyle to better manage their disorder and minimize complications. Patients with low blood counts should avoid blood-thinning medications, alcohol, and activities that could lead to injury. Patients with high blood count are advised to drink plenty of water, exercise regularly, and to avoid smoking. Many people with platelet disorders can live healthy and fulfilling lives with proper treatment and precautions.