Pseudocholinesterase Deficiency

What is pseudocholinesterase deficiency?

Pseudocholinesterase (soo-doe-ko-luh-NEH-stur-ays) deficiency is a condition that makes you extremely sensitive to a specific group of anesthetic medications, known as muscle relaxants. As a result of this enzyme deficiency, you can develop prolonged side effects like temporary muscle paralysis. People with this condition can’t move or breathe on their own until the medication flushes out of their system.

It happens when your body doesn’t produce enough pseudocholinesterase — an enzyme that helps metabolize (break down) medications (called choline esters) used during general anesthesia. Succinylcholine and mivacurium are two of the most common choline esters used for anesthesia.

How common is pseudocholinesterase deficiency?

Pseudocholinesterase deficiency is uncommon. It affects about 1 out of every 3,200 to 5,000 people in the general population.

What are the symptoms of pseudocholinesterase deficiency?

People with pseudocholinesterase deficiency usually don’t know they have it until they receive choline esters during general anesthesia. Hallmark symptoms include:

• Extreme muscle relaxation that lasts several hours longer than expected.
• Temporary paralysis of your respiratory muscles.

It can take several hours for pseudocholinesterase deficiency symptoms to improve. This timeline varies from person to person.

During this time, your provider will keep you under anesthesia and on a ventilator until the effects of the muscle relaxant wear off.

What causes a pseudocholinesterase deficiency?

You can be born with pseudocholinesterase deficiency (inherited) or develop it later in life (acquired).

People who inherit the condition have a mutation (change) in their BCHE gene. This gene contains instructions that your body uses to make the pseudocholinesterase enzyme. If you have the BCHE gene mutation, you either produce very little pseudocholinesterase enzyme or you don’t produce it at all.

You can also develop pseudocholinesterase deficiency over time. Acquired pseudocholinesterase deficiency causes include a variety of health conditions and medications.

Health conditions that may result in pseudocholinesterase deficiency include:

• Malnutrition.
• Burn injuries.
• Kidney disease.
• Liver disease.
• Hypothyroidism.
• Cancer.
• Pregnancy.

There are also certain medications that could increase your risk for pseudocholinesterase deficiency. These medications include:

• MAO inhibitors like phenelzine (Nardil®).
• Oral contraceptives (birth control).
• Echothiophate eye drops.
• Metoclopramide.
• Cyclophosphamide.
• Pyridostigmine.

How do healthcare providers diagnose pseudocholinesterase deficiency?

Your healthcare provider may suspect pseudocholinesterase deficiency if you have difficulty regaining muscle control and breathing after general anesthesia. To confirm your diagnosis, they can run a blood test to check your pseudocholinesterase enzyme levels.

If you have a family member with the condition, a healthcare provider can do genetic testing to find out if you have it, too. This test uses a blood sample to determine whether you have a BCHE gene mutation.

If your provider suspects you have this condition, they can use other types of muscle relaxants that don’t depend on the pseudocholinesterase enzyme.

How do you treat pseudocholinesterase deficiency?

If you receive general anesthesia and develop symptoms of pseudocholinesterase deficiency, you’ll likely need immediate medical care. Your healthcare team will monitor you while you recover. If necessary, they’ll keep you under anesthesia and use mechanical ventilation to help you breathe until you can breathe on your own again.

Can I prevent pseudocholinesterase deficiency?

You can’t prevent inherited pseudocholinesterase deficiency. But if it runs in your family, you can get tested for the BCHE gene mutation before undergoing general anesthesia. This can help you avoid surgical complications.

If you have the gene mutation, your provider will avoid choline esters and choose another type of anesthetic instead. Rocuronium is one of the most used anesthetic medications for people with pseudocholinesterase deficiency.

You may be able to reduce your risk for acquired pseudocholinesterase deficiency by treating underlying health conditions like malnutrition or chronic kidney disease (CKD). You can also ask your healthcare provider about switching medications if you’re taking something that lowers your production of pseudocholinesterase enzyme.

What drugs should be avoided with pseudocholinesterase deficiency?

If you have a pseudocholinesterase deficiency diagnosis, you should avoid certain anesthetic medications, including:

• Succinylcholine.
• Mivacurium.
• Procaine.
• Chloroprocaine.
• Benzocaine.
• Tetracaine.

What can I expect if I have pseudocholinesterase deficiency?

If you receive a pseudocholinesterase deficiency diagnosis, letting your healthcare providers know is the best thing you can do — especially those you see for surgical procedures.

You should also let your family know so they can get tested for the BCHE gene mutation. That way, they can inform their healthcare providers before undergoing any type of surgery.

Consider wearing a medical ID bracelet that informs healthcare providers about your condition. This can be helpful if you ever need emergency surgery.

What questions should I ask my healthcare provider?

If you have inherited or acquired pseudocholinesterase deficiency, here are a few questions you might want to ask your healthcare provider:

• What specific medications should I avoid?
• Was I born with this condition? Or did another condition cause it?
• Should my family consider genetic testing?

A note from Cleveland Clinic

Having surgery can be stressful. Most of us worry so much about the procedure, we don’t even consider that we could have a negative reaction to anesthesia. There’s no cure for pseudocholinesterase deficiency. But knowing whether you have it can help you avoid symptoms like temporary muscle paralysis and breathing issues after surgery. If you have pseudocholinesterase deficiency, tell other family members so they can get genetic testing and avoid potential complications on their health journeys.