Causes of Low Platelet Count

The medical term for a low platelet count is thrombocytopenia. Low platelet disorders may be from reduced platelet production or platelet destruction problems. These problems may be inherited conditions, caused by medications or toxins, or the result of a disease or immune system condition. Symptoms can include bruising easily, bleeding gums, nosebleeds, blood in your urine or stool, profuse and prolonged bleeding and petechiae.

Reduced Production

• Your bone marrow produces platelets. Diseases that affect your bone marrow can result in less production of new platelets. These include leukemia, some types of anemia and viral infections, such as HIV. Some cancers may also be the cause, as well as excessive alcohol use and chemotherapy.

Platelet Destruction

• There are conditions that may involve the destruction of platelets faster than your body is able to produce them. In idiopathic thrombocytopenic purpura, your immune system attacks the platelets. Other autoimmune diseases can also be responsible, such as rheumatoid arthritis or lupus. Two rare conditions are thrombotic thrombocytopenic purpura, in which the body forms small blood clots throughout, and hemolytic uremic syndrome, in which there is an acute drop in platelets, red blood cells are destroyed and kidney function is diminished.

Medications

• Some medications can cause the immune system to mistakenly destroy platelets. These include heparin, antibiotics containing sulfa, quinidine, quinine, diuretics, anti-seizure medications, some oral diabetes medications and rifampin. With heparin, there's a higher risk of a clot forming that can be life-threatening.

Diagnosis

• If thrombocytopenia is mild, there may be no symptoms. The platelet count may be low on a blood test even though no signs of the problem are evident. Your doctor may want to closely watch your platelet count if you have a condition that increases your risk of thrombocytopenia. Before treating it, your doctor should determine the condition that caused it.

Treatments

• Treatments include medications that can stop antibodies from attacking platelets, such as corticosteroids. If these aren't successful, medications to suppress the immune system may be used, such as cyclophosphamide or azathioprine. In cases of chronic idiopathic thrombocytopenic purpura, surgery to remove the spleen may be necessary. Blood transfusions or platelet concentrates may be given to replace lost blood.

Complications

• With severe thrombocytopenia, there is a risk of bleeding into the digestive tract or brain. Although these are rare, they are life-threatening complications. If kidney damage is permanent in the case of hemolytic uremic syndrome, lifelong dialysis may be necessary.