OVERVIEW

What is Thrombotic Thrombocytopenic Purpura (TTP)?

Thrombotic Thrombocytopenic Purpura, abbreviated as TTP, is a relatively rare disseminated microvascular thrombosis-hemorrhage syndrome. Clinically, it is typically characterized by a pentad of symptoms: thrombocytopenic purpura, microangiopathic hemolytic anemia, neuropsychiatric symptoms, renal impairment, and fever. Plasma exchange is the first-line treatment, with over 80% of cases being curable.

Is Thrombotic Thrombocytopenic Purpura (TTP) common?

The annual incidence of TTP was originally 1 per million, but recent trends show an increase, ranging approximately from 2 to 8 per million. It is slightly more common in women and predominantly occurs during childbearing age.

What are the types of Thrombotic Thrombocytopenic Purpura (TTP)?

TTP can be classified into hereditary TTP and acquired TTP. Acquired TTP is further divided into primary and secondary types. Hereditary TTP is caused by ADAMTS13 gene mutations leading to reduced or absent enzyme activity. Idiopathic TTP, the main clinical type, occurs due to the presence of anti-ADAMTS13 autoantibodies in patients, resulting in decreased or absent ADAMTS13 activity.

SYMPTOMS

What are the common symptoms and clinical manifestations of thrombotic thrombocytopenic purpura (TTP)?

• Fever: Present in over 90% of patients.
• Microangiopathic hemolytic anemia: Varying degrees of anemia. About half of cases exhibit jaundice, 20% show hepatosplenomegaly, and a few may present with Raynaud's phenomenon.
• Bleeding due to thrombocytopenia: Primarily affects the skin and mucous membranes, presenting as petechiae, ecchymosis, purpura, epistaxis, retinal hemorrhage, genitourinary or gastrointestinal bleeding, and in severe cases, intracranial hemorrhage. The severity depends on the degree of thrombocytopenia.
• Neurological changes: Include headache, mental status changes, localized motor or sensory deficits, blurred vision, or even coma. A hallmark feature is fluctuating symptoms, often transient initially, with possible improvement or recurrence. The variability of neurological manifestations is a key characteristic of TTP and often determines prognosis.
• Renal impairment: May present with proteinuria, hematuria, cylindruria, and elevated blood urea nitrogen and creatinine levels.

What are the potential consequences of thrombotic thrombocytopenic purpura (TTP)?

Severe cases may lead to acute renal failure and microvascular involvement in the heart, lungs, or abdominal organs, ultimately resulting in death.

CAUSES

What are the common causes of thrombotic thrombocytopenic purpura (TTP)?

• Primary TTP: The cause is unknown. The onset may be closely related to viral infections, including herpes virus, EB virus, cytomegalovirus, parvovirus B19, measles virus, mumps virus, rubella virus, and hepatitis virus.
• Secondary TTP:
• Impaired platelet production: Commonly seen in cases of reduced megakaryocyte production due to physical or chemical factors; bone marrow infiltrative diseases; hematopoietic stem cell disorders; infectious diseases; dysregulation of platelet production; genetic diseases.
• Ineffective platelet production: Occurs in vitamin B₁₂ or folate deficiency, some cases of paroxysmal nocturnal hemoglobinuria, and myelodysplastic syndromes.
• Increased platelet destruction or excessive consumption: Caused by certain immune disorders; infections leading to thrombocytopenia; alloimmune thrombocytopenia.

Who is commonly affected by thrombotic thrombocytopenic purpura (TTP)?

Thrombotic thrombocytopenic purpura mostly occurs in individuals aged 15–50, with a higher prevalence in women. The disease often presents as an acute fulminant form, while 10%–20% of cases manifest as chronic recurrent episodes.

Under what circumstances is thrombotic thrombocytopenic purpura (TTP) commonly seen?

For patients prone to thrombotic thrombocytopenic purpura, various infectious diseases can lead to impaired or insufficient platelet production, thereby triggering TTP.

DIAGNOSIS

What tests are needed for thrombotic thrombocytopenic purpura (TTP)?

• Complete blood count (CBC): Patients exhibit varying degrees of anemia. Reticulocytes are elevated, schistocytes exceed 2%, and platelet counts are significantly reduced.
• Blood biochemical tests: Patients show varying increases in blood urea nitrogen and creatinine. Elevated troponin T levels indicate myocardial damage.
• Coagulation tests: Prolonged bleeding time, poor clot retraction, and a positive tourniquet test.
• Von Willebrand factor-cleaving protease (ADAMTS13) activity analysis: Hereditary TTP patients have ADAMTS13 activity below 5%, while some acquired TTP patients may also show significant reductions. Inhibitors of the enzyme may also be detected in plasma.
• Chest X-ray: Diffuse alveolar and interstitial infiltrative lesions may be observed.

When performing these tests, precautions should be taken to prevent reinfection and worsening anemia caused by the procedures.

Which diseases is thrombotic thrombocytopenic purpura (TTP) easily confused with?

Hemolytic uremic syndrome (HUS); disseminated intravascular coagulation (DIC); Evans syndrome; systemic lupus erythematosus (SLE); pregnancy-induced hypertension syndrome.

TREATMENT

Which department should I visit for thrombotic thrombocytopenic purpura (TTP)?

Hematology.

How to provide first aid during a TTP episode?

For patients with a confirmed TTP diagnosis, if nosebleeds occur, first calm the patient and take measures to stop the bleeding, then call 120. If symptoms like vomiting blood or headaches due to intracranial bleeding appear, call 120 immediately.

How is thrombotic thrombocytopenic purpura (TTP) treated?

• Plasma exchange and fresh frozen plasma infusion: Plasma exchange is the first-line treatment. Fresh or frozen plasma should be used as the replacement fluid. Due to the severity of TTP, treatment should begin immediately upon diagnosis or strong suspicion. Hereditary TTP patients may receive fresh or frozen plasma infusions, administered 1–2 times daily. In cases of severe kidney failure, plasma exchange can be combined with hemodialysis. Plasma exchange is often ineffective for secondary TTP patients.
• Immunosuppressive therapy: For primary TTP with inhibitors, vincristine or other agents may be added to reduce autoantibody production.
• Intravenous immunoglobulin: Suitable for cases where plasma exchange is ineffective or for recurrent episodes.
• Severe anemia may require packed red blood cell transfusions.

What types of medications are used to treat TTP?

• Corticosteroids: Prednisone;
• Immunosuppressants: Dexamethasone, vincristine;
• Antiplatelet drugs: Dipyridamole, aspirin.

Is continued medication necessary after TTP improves?

Yes, medication must be continued after improvement. Patients should focus on infection prevention and avoid excessive fatigue.

What should be noted during hospitalization for TTP?

• Assist doctors with blood transfusion therapy;
• Maintain bowel regularity to prevent constipation, as straining can increase intracranial pressure and trigger bleeding;
• Prevent infections and provide active care.

Is follow-up required after discharge for TTP? How?

Yes, follow-up is necessary. The schedule depends on the patient's condition, but regular blood tests to monitor platelet counts are essential.

Can TTP be completely cured?

Statistics show that over 80% of TTP patients can achieve a cure and long-term survival after plasma exchange.

Can TTP recur?

The recurrence rate after TTP remission is relatively high, approximately 30%–50%.

DIET & LIFESTYLE

What should patients with thrombotic thrombocytopenic purpura (TTP) pay attention to in daily life?

• The diet should be low-residue or residue-free; encourage patients to drink more water and consume fresh vegetables and fruits.
• Avoid strenuous exercise, get plenty of rest, and prevent injuries.
• Strictly follow the doctor's instructions, take medication on time and in the prescribed dosage, and do not stop taking it without permission.
• Schedule regular follow-ups to monitor the condition.
• Patients need to learn about thrombotic thrombocytopenic purpura to recognize worsening symptoms promptly and seek immediate medical attention.
• Avoid contact with infected individuals while taking medication, wear a mask in public places, and prevent colds.
• Seek immediate medical care if bleeding occurs.

PREVENTION

How to Prevent Thrombotic Thrombocytopenic Purpura (TTP)?

• Prevent infections actively: Key to disease prevention.
• Strengthen physical fitness: Improve disease resistance by engaging in suitable physical exercises.
• Pay attention to lifestyle adjustments: Keep rooms clean and well-ventilated for effective infection prevention.
• Enhance health education: Fully understand TTP, learn self-diagnosis methods, and how to stop bleeding quickly.
• Regular health check-ups: Conduct routine blood tests and biochemical tests for early detection, diagnosis, and treatment.