Pseudocholinesterase Deficiency

If you have pseudocholinesterase deficiency, your body has no pseudocholinesterase or an amount that’s too low. This enzyme is needed to break down (metabolize) drugs known as choline esters. Succinylcholine is used as part of anesthesia to relax the muscles during medical procedures.

Pseudocholinesterase deficiency causes the muscles to stay relaxed for too long after getting succinylcholine. This prevents you from moving or breathing on your own for a few hours longer than expected. How long it takes your body to metabolize the drug depends on how much pseudocholinesterase enzyme you produce and how well it functions.

Pseudocholinesterase deficiency can be inherited or acquired.

Inherited pseudocholinesterase deficiency

Inherited pseudocholinesterase deficiency is caused by a change in the butyrylcholinesterase (BCHE) gene. This gene provides the instructions to make the pseudocholinesterase enzyme that’s needed to break down choline esters. If you have this changed gene, either you don’t produce this enzyme or the enzyme does not work well.

Genetic testing can show whether you have this gene change. To have pseudocholinesterase deficiency, you must inherit two affected genes — one from each of your parents (autosomal recessive inheritance). If you inherit only one affected gene, you won’t have the disorder. But you may process choline esters at a slower rate than people who don’t have an affected gene.

With one affected gene, you are a carrier and can pass the gene change to your children. But they won’t develop the disorder unless they also inherit an affected gene from the other parent.

Acquired pseudocholinesterase deficiency

You can develop pseudocholinesterase deficiency as a result of conditions that cause you to make less of the pseudocholinesterase enzyme. These conditions include chronic infections, kidney or liver disease, malnutrition, severe burns, cancer, or pregnancy. Certain medications also can reduce production of the enzyme. Acquired pseudocholinesterase deficiency is not inherited and cannot be passed to your children.

Your risk of having pseudocholinesterase deficiency is higher if you or a first-degree relative, such as a parent, child or sibling, has:

• A gene change that causes the disorder.
• A history of a problem during anesthesia that is suspected to be caused by pseudocholinesterase deficiency.

If you have a family history of pseudocholinesterase deficiency or have a family member who had any problem with anesthesia, tell your health care provider before getting a medical procedure that requires anesthesia.

If you have a family history of pseudocholinesterase deficiency, you can prevent problems during anesthesia by having testing before the procedure.

Evaluating your risk of pseudocholinesterase deficiency allows your health care provider to avoid certain muscle relaxants, if needed.