A high platelet count can be caused by a bone marrow condition that produces too many platelets, a separate disease, or another condition that affects platelet count, according to the National Heart, Lung, and Blood Inst... More »

www.reference.com Health Medical Ranges & Levels

An elevated platelet count generally means one of two things: reactive thrombocytosis or essential thrombocythemia. Reactive thrombocytosis means that an underlying condition has elevated the platelets, while essential t... More »

www.reference.com Health Medical Ranges & Levels

Generally, a count that is over 500,000 platelets per microliter of blood is considered high enough to seek the underlying cause, notes Mayo Clinic. A normal platelet range is 150,000 to 450,000 platelets. A high platele... More »

Causes of a high platelet count include recent spleen removal, cancer, chronic myelogenous leukemia and the use of certain medications, according to MedlinePlus. An increased platelet count indicates the body is making m... More »

www.reference.com Health Medical Ranges & Levels

Symptoms of a high platelet count include headache, bleeding, feeling weak, and numbness in the hands or feet, states Healthgrades. Blood-clotting symptoms, including nausea, seizures, dizziness, difficulty breathing and... More »

Causes of a low lymphocyte count include autoimmune disorders, blood diseases, infections, and treatment with steroids, radiation or chemotherapy drugs, states the National Heart, Lung, and Blood Institute. The medical t... More »

Low platelet count can be caused by acquired or inherited conditions, which may cause the body's bone marrow to decrease platelet production, according to the National Heart, Lung, and Blood Institute. The body may destr... More »