Apheresis and Therapeutic Plasma Exchange

Overview

Apheresis and Therapeutic Plasma Exchange, also called PLEX, are specialised procedures offered under the Centre of Transfusion Medicine. These treatments involve removing blood from the body, separating it into components, and either collecting or replacing a specific part before returning the remaining blood to the patient.

PLEX is mainly used to remove harmful antibodies, abnormal proteins, toxins, or inflammatory substances from the plasma. It can be life-saving in selected neurological, blood, kidney, autoimmune, and transplant-related conditions.

What Are Apheresis and Therapeutic Plasma Exchange?

Apheresis is a procedure in which blood is passed through a special machine that separates it into components such as plasma, red blood cells, white blood cells, and platelets. Depending on the medical need, one component may be removed, collected, or replaced, while the rest of the blood is returned to the patient.

Therapeutic Plasma Exchange is a type of apheresis in which the patient’s plasma is removed and replaced with a suitable replacement fluid, such as albumin or donor plasma. This helps reduce harmful substances circulating in the blood.

PLEX may be used in conditions such as:

• Thrombotic thrombocytopenic purpura, also called TTP

• Guillain-Barre syndrome

• Myasthenia gravis

• Neuromyelitis optica and selected severe demyelinating diseases

• Certain autoimmune kidney diseases

• Antibody-mediated transplant rejection

• Hyperviscosity syndrome

• Some complications of multiple myeloma or Waldenstrom macroglobulinemia

• Selected severe neurological, hematological, renal, or autoimmune disorders

The decision to perform PLEX is based on the diagnosis, severity, urgency, and evidence-based clinical guidelines.

Causes and Risk Factors

PLEX may be required when disease-causing substances are present in the plasma and need to be removed quickly. These may include autoantibodies, immune complexes, abnormal proteins, toxins, or clotting-related factors.

Common reasons for referral include:

• Sudden severe weakness due to immune nerve disease

• Life-threatening blood disorders such as TTP

• Autoimmune diseases affecting the kidneys, nerves, or other organs

• Transplant rejection due to antibodies

• Abnormal proteins causing thickened blood

• Severe disease not responding adequately to standard medicines

• Need for rapid removal of harmful plasma substances

Patients may need special precautions if they have low blood pressure, active bleeding, infection, low calcium levels, allergy to plasma products, poor vein access, heart disease, or clotting abnormalities.

Symptoms

Symptoms depend on the underlying disease for which apheresis or PLEX is recommended. Patients may be referred when symptoms are severe, rapidly worsening, or linked to harmful substances in the plasma.

Possible symptoms include:

• Sudden or progressive muscle weakness

• Difficulty breathing or swallowing in neurological conditions

• Numbness, tingling, or nerve-related symptoms

• Easy bruising, bleeding, or small red-purple skin spots

• Confusion, seizures, or neurological changes

• Reduced urine output or kidney dysfunction

• Severe fatigue or anaemia

• Blurred vision, headache, or dizziness due to thickened blood

• Swelling, high blood pressure, or signs of autoimmune kidney disease

• Worsening organ function after transplant

Emergency care is needed for breathing difficulty, severe weakness, confusion, seizures, uncontrolled bleeding, chest pain, fainting, or sudden neurological symptoms.

Diagnosis

Before starting apheresis or PLEX, doctors confirm the diagnosis and assess whether the procedure is appropriate and safe.

Common assessments include:

• Medical history and physical examination

• Complete blood count

• Kidney and liver function tests

• Electrolytes, especially calcium levels

• Coagulation profile

• Blood group and crossmatch when plasma replacement may be needed

• Tests for antibodies, abnormal proteins, or autoimmune disease

• Infection screening when required

• Neurology, hematology, nephrology, transplant, or critical care evaluation

• Assessment of vein access or need for a central venous catheter

During treatment, blood pressure, pulse, oxygen level, symptoms, fluid balance, and procedure-related reactions are closely monitored.

Treatment Options

Treatment depends on the condition being treated and the patient’s overall health. PLEX is often used along with other therapies rather than as a standalone treatment.

Care may include:

• Therapeutic Plasma Exchange using albumin or plasma replacement

• Multiple treatment sessions over several days, depending on the condition

• Central venous catheter placement when peripheral veins are not suitable

• Calcium supplementation if citrate-related low calcium symptoms occur

• Medicines to treat the underlying disease, such as steroids, immunosuppressants, anticoagulants, or disease-specific therapy

• Blood product support when needed

• Monitoring for blood pressure changes, allergic reactions, bleeding, infection, or electrolyte imbalance

• Coordination with hematology, neurology, nephrology, rheumatology, transplant, or ICU teams

Some patients may feel tired, cold, lightheaded, nauseous, or have tingling around the mouth or fingers during the procedure. These effects are usually monitored and managed by the care team.

Prevention and Outlook

Apheresis and PLEX do not prevent all diseases, but they can reduce complications in selected conditions by rapidly removing harmful plasma components. Early referral is important in time-sensitive conditions such as TTP, severe myasthenia gravis, Guillain-Barre syndrome, or antibody-mediated transplant rejection.

The outlook depends on the underlying disease, severity, timing of treatment, and response to other medicines. In many conditions, PLEX can help stabilise the patient, reduce disease activity, and support recovery when used as part of a broader treatment plan.

Frequently Asked Questions

1. What is the difference between apheresis and PLEX?
   Apheresis is the broader process of separating blood into components. PLEX is a type of apheresis in which plasma is removed and replaced with another fluid.

2. Is PLEX the same as dialysis?
   No. Both use machines to filter blood, but dialysis removes waste and excess fluid mainly due to kidney failure, while PLEX removes plasma containing harmful antibodies or abnormal proteins.

3. How long does a PLEX session take?
   A session usually takes a few hours, depending on the patient’s size, condition, access type, and treatment plan.

4. Is Therapeutic Plasma Exchange painful?
   The procedure itself is not usually painful, though needle or catheter placement may cause brief discomfort. Some patients may feel cold, tired, lightheaded, or tingling during treatment.

5. How many sessions are needed?
   The number of sessions depends on the condition being treated and response to therapy. Some patients need only a few sessions, while others need a planned course over several days or weeks.

6. Are there risks with PLEX?
   Yes, possible risks include low blood pressure, low calcium, allergic reactions, bleeding, infection, catheter-related complications, and temporary fatigue. The care team monitors closely to reduce these risks.