痔疮指南：症状、原因和治疗

Overview

Idiopathic thrombocytopenic purpura (ITP), now more commonly called immune thrombocytopenia, is an autoimmune condition. Your immune system mistakenly attacks and destroys platelets—the blood cells that help form clots and stop bleeding. This leads to a low platelet count (thrombocytopenia). “Idiopathic” means the exact trigger is often unknown. ITP can be acute (sudden and short-term, more common in children after a viral illness) or chronic (lasting more than 12 months, more common in adults). It is not cancer and is not usually inherited.

Platelet counts below about 100,000 per microliter define thrombocytopenia; many people with ITP have counts under 50,000 or even much lower. Severity ranges from mild (few symptoms) to severe (active bleeding). With modern treatments, most people live full lives.

Signs & Symptoms

Symptoms depend on how low the platelet count falls and how quickly it drops. Some people have no symptoms and discover ITP on a routine blood test. Common signs include:

• Easy or excessive bruising (ecchymoses)
• Tiny red or purple pinpoint spots on the skin (petechiae), often on the lower legs
• Larger purple patches (purpura)
• Nosebleeds or bleeding gums that are hard to stop
• Blood in urine or stool
• Unusually heavy or prolonged menstrual periods
• Prolonged bleeding from cuts
• Fatigue (common even without major bleeding)

Causes & Risk Factors

In ITP the immune system produces antibodies that coat platelets, marking them for destruction mainly in the spleen. Why this happens is not fully understood. In children it often follows a viral infection. In adults it may appear without a clear trigger or be linked to other autoimmune conditions, certain infections (such as Helicobacter pylori, hepatitis C, or HIV), medications, or pregnancy. Risk factors include being female (especially of childbearing age), having other autoimmune diseases (for example lupus or rheumatoid arthritis), and recent viral illness. ITP is not contagious.

Diagnosis

There is no single definitive test for ITP. Diagnosis is made by finding a low platelet count on a complete blood count (CBC) while other blood cell lines are usually normal, and by ruling out other causes of low platelets (such as medication effects, infections, bone-marrow problems, or other blood disorders). Your doctor will take a detailed history and perform a physical exam looking for bruising, petechiae, or enlarged spleen (usually absent in ITP). Additional tests may include blood-smear review, tests for infections or autoimmune markers, and sometimes a bone-marrow exam if the picture is unclear or if you are older. Imaging or other specialized tests are used only when needed.

Treatment & Management

Treatment is individualized based on platelet count, bleeding symptoms, age, lifestyle, and preferences. Many people with mild ITP and no significant bleeding need only careful observation and periodic blood counts. First-line treatments for those who need therapy often include corticosteroids (such as prednisone) to reduce immune destruction of platelets, or intravenous immunoglobulin (IVIG) for a rapid but temporary rise in counts. Second-line options include rituximab (an antibody that targets certain immune cells), thrombopoietin-receptor agonists (medicines that stimulate the bone marrow to make more platelets, such as eltrombopag or romiplostim), and other immunosuppressants. Splenectomy (surgical removal of the spleen) can produce long-term remission in many adults but is used more selectively today. Emergency treatment for life-threatening bleeding may include platelet transfusions, high-dose steroids, IVIG, and other supportive measures. Children often recover spontaneously within weeks to months; adults more often have a chronic course that can still be managed effectively.

Living With It

Most people with ITP can lead active lives with appropriate monitoring and precautions. Work closely with a hematologist. Avoid activities with high risk of injury when counts are very low. Discuss all medications and supplements with your doctor—some (including aspirin, NSAIDs like ibuprofen, and certain herbal products) can increase bleeding risk. Maintain good oral hygiene to reduce gum bleeding, and inform dentists and other clinicians about your diagnosis before procedures. Women of childbearing age should discuss pregnancy planning, as ITP can affect mother and baby and requires specialized care. Emotional support matters; living with a chronic bleeding risk can cause anxiety. Support groups and counseling can help. Regular follow-up blood tests allow timely adjustment of treatment.