Plasma Exchange (Plasmapheresis Treatment)

Plasma is the fluid component of blood. Among its many jobs, plasma carries antibodies, which are proteins the body makes to fight germs. In an autoimmune condition like neuromyelitis optica spectrum disorder (NMOSD), abnormal antibodies attack healthy tissue.^1,2

What is plasmapheresis?

In plasmapheresis, a machine removes the abnormal antibodies and other inflammatory components in your plasma. Plasmapheresis may be called plasma exchange (PLEX) or therapeutic plasma exchange (TPE).³

How does plasma exchange help treat NMOSD?

In NMOSD, the body produces an antibody targeting AQP4 (AQP4-IgG) that results in damage to nerve cells and their protective coating in the optic nerve, spinal cord, and brain. This nerve coating is called myelin. While many people with NMOSD have the AQP4 antibody (AQP4-IgG) in their blood, 1 in 4 people do not. This adds to the complexity of the disease.^4,5

PLEX may be an effective treatment in those who have sudden, severe NMOSD attacks that do not respond to high-dose intravenous (through the vein, or IV) steroids. PLEX involves removing blood through a large IV and using a machine to separate the blood cells from the fluid (plasma). Blood cells are then mixed with a replacement solution and returned to the body. By removing and replacing the plasma, PLEX helps remove the abnormal, bad AQP4 antibody and other inflammatory components that may be contributing to the NMOSD attack.^6,7

Types of plasmapheresis

Apheresis is the removal of whole blood. Using a device that spins the blood quickly, the blood components are separated. Plasmapheresis is a type of apheresis. Other types of apheresis include:^3,8

• Plateletpheresis, which removes platelets for conditions where complications of bleeding occur
• Leukapheresis, which removes white blood cells for conditions such as leukemia
• Stem cell harvesting, which removes bone marrow stem cells for transplantation
• PLEX is the apheresis used in NMOSD

What are the possible side effects?

Plasma exchange is a common procedure. Like other procedures, PLEX can have possible side effects. Side effects of PLEX relate to fluid and blood balance problems. These may include:⁹

• Muscle spasms
• Tingling in fingers or toes
• Itching and rash (urticaria)
• Blood pressure problems
• Belly pain, nausea, and vomiting
• Allergic reaction
• Fever
• Low potassium, calcium, or clotting factors in the blood

These are not all the possible side effects of plasma exchange. Talk to your doctor about what to expect when undergoing plasma exchange. You should also call your doctor if you have any changes that concern you during plasma exchange.

Other things to know

Plasma exchange can affect the levels of some drugs in your body. Talk to your doctor about your current drug regimen and what changes you may need to take before or after the procedure.^9,10

An IV catheter will need to be placed in your arm or neck. You may have discomfort or bruising at the insertion site. You may be instructed to keep your arm propped on a pillow during the procedure. You may have to squeeze and release your fist (pump your fist) to help promote blood flow.⁹

Plasma exchange takes about 2 to 3 hours. In NMOSD, PLEX is often performed every other day for 5 sessions. When the procedure is over, you may feel tired and need to rest. Your doctor will advise you on aftercare, which usually includes resting and drinking fluids.⁹

Studies have shown that PLEX may improve NMOSD symptoms after an attack. However, this treatment should be started early after an attack for it to be effective.⁷

While plasma exchange may help NMOSD symptoms, it does not cure the disease. Plasma exchange may be part of your treatment plan. Talk to your doctor about the various treatment options you have.²

Before beginning treatment for NMOSD, tell your doctor about all your health conditions and any other drugs, vitamins, or supplements you are taking. This includes over-the-counter drugs.