Low platelet count, or thrombocytopenia, is an abnormally low count of platelets, the blood particles that prevent blood loss by aiding in the formation of blood clots. A normal platelet count is defined as 150,000 to 350,000 platelets in one microliter of blood. Mild symptoms of thrombocytopenia occur when the platelet count falls below 50,000 platelets per microliter, according to the Merck Manuals Online Medical Library. When the platelet count falls below 20,000 platelets per microliter of blood, the condition is considered severe.
Causes
There are a number of different reasons for a low platelet count. Certain disorders can cause an enlargement of the spleen, a body organ that aids in the fight against infection. When the spleen is enlarged, it can trap platelets, which results in a decrease in platelets available in the blood. Bone marrow diseases can also cause a low platelet count. Platelets are produced in the bone marrow; diseases and infections that affect the bone marrow, such as leukemia or HIV, can cause a reduced production of platelets. Low platelet count can also be caused by an increased breakdown or destruction of platelets. Certain conditions, such as autoimmune diseases, pregnancy, chronic alcohol use, medication and bacteria in the blood can cause an increase in platelet breakdown.
Symptoms
Symptoms of a low platelet count include excessive bruising, superficial bleeding, prolonged bleeding, spontaneous nosebleeds and blood in the urine. As the platelet count lowers, symptoms become more severe. A platelet count below 20,000 platelets per microliter of blood may result in bleeding in the digestive tract or brain, which can be fatal. The elapsed time before the onset of symptoms depends on the underlying cause for the low platelet count.
Diagnosis
If thrombocytopenia is suspected after a physical exam, your doctor will perform a complete blood count, which measures total blood volume including red blood cells, white blood cells, platelets and blood plasma. If the platelet count is below 150,000 platelets per microliter of blood, a diagnosis of thrombocytopenia will be given.
Treatment
Mild cases of thrombocytopenia do not require treatment. For more severe cases of thrombocytopenia, treatment is determined based on the underlying condition causing the low platelet count. In addition to treatment of the underlying condition, blood transfusions may also be given. Blood transfusions can replace large amounts of lost blood by providing a combination of red blood cells and platelets.
Lifestyle
After a diagnosis of thrombocytopenia, it is important to follow certain guidelines in order to decrease the chances of further injury. Contact sports should be avoided since they carry a high risk of injury and thus an increased chance of uncontrollable bleeding. Alcohol, which slows the production of platelets, should be avoided as well. Certain pain medications, such as aspirin and ibuprofen, can also affect platelet function and should be taken only after talking with your doctor.
