Thrombocytopeni

Thrombocytopeni, or thrombocytopenia, is a condition characterized by an abnormally low platelet count in the blood, often defined as fewer than 150,000 platelets per microliter in adults. Platelets are essential for normal hemostasis, and low counts increase the risk of prolonged bleeding after injury.

Causes include decreased production from bone marrow disorders (such as aplastic anemia, myelodysplastic syndromes, leukemia), nutrient deficiencies (vitamin B12 or folate), or effects of chemotherapy or radiation. Increased destruction or sequestration occurs in immune thrombocytopenia (ITP), drug-induced thrombocytopenia, certain infections (HIV, hepatitis C), and splenic enlargement. Dilutional thrombocytopenia can follow massive transfusion.

Symptoms range from none to mucocutaneous bleeding. Common signs include easy bruising, petechiae, nosebleeds, gum bleeding, and heavier menstrual periods. Severe thrombocytopenia or rapid drops in count raise the risk of serious bleeding, including intracranial hemorrhage, though this is uncommon.

Diagnosis relies on a low platelet count seen in a complete blood count, with examination of a peripheral smear and medical history. Additional tests target the underlying cause and bleeding risk, such as investigations for infections, autoimmune factors, and bone marrow evaluation if indicated.

Management is directed at the cause and bleeding risk. Mild cases without symptoms may be observed. Treatments for immune thrombocytopenia include corticosteroids or intravenous immunoglobulin; refractory cases may use thrombopoietin receptor agonists or splenectomy. Platelet transfusions are used for active or life-threatening bleeding. Avoidance of NSAIDs and certain anticoagulants is often advised when platelets are low.

Prognosis varies with etiology. Some thrombocytopenias resolve with treatment of the underlying condition, while others become chronic and require long-term management.