Pseudocholinesterase deficiency

Title

Other Names:

Succinylcholine Sensitivity; Apnea, Postanesthetic; Cholinesterase 2 Deficiency; Succinylcholine Sensitivity; Apnea, Postanesthetic; Cholinesterase 2 Deficiency; Pseudocholinesterase E1; Suxamethonium Sensitivity; Butyrylcholinesterase deficiency See More

Categories:

Congenital and Genetic Diseases; Metabolic disorders

Summary Summary

Pseudocholinesterase deficiency is a condition that causes increased sensitivity to certain muscle relaxant drugs used during general anesthesia (choline esters). These drugs relax the muscles used for movement, including those used for breathing. Normally, the muscles are able to move again a few minutes after the drugs are given. People with pseudocholinesterase deficiency may not be able to move or breathe on their own for a few hours after these drugs are given. They therefore may need mechanical ventilation until the drugs are cleared from the body. People with this condition may also have increased sensitivity to other types of drugs as well as to some agricultural pesticides.^[1]

Pseudocholinesterase deficiency can be inherited (genetic) or acquired. When it is inherited, it is autosomal recessive and caused by mutations in the BCHE gene. Acquired pseudocholinesterase deficiency may have various causes such as chronic infection, kidney or liver disease, malnutrition, major burns, cancer, or various medications.^[1]^[2]

Last updated: 9/16/2016

Symptoms Symptoms

The Human Phenotype Ontology (HPO) provides the following list of features that have been reported in people with this condition. Much of the information in the HPO comes from Orphanet, a European rare disease database. If available, the list includes a rough estimate of how common a feature is (its frequency). Frequencies are based on a specific study and may not be representative of all studies. You can use the MedlinePlus Medical Dictionary for definitions of the terms below.

Signs and Symptoms	Approximate number of patients (when available)
Apnea	-
Autosomal recessive inheritance	-

Last updated: 9/1/2016

Cause Cause

There are both genetic (inherited) and acquired causes of pseudocholinesterase deficiency.^[2]^[1]

Inherited pseudocholinesterase deficiency can be caused by mutations in the BCHE gene. This gene provides instructions for making the pseudocholinesterase enzyme, known as butyrylcholinesterase. This enzyme is made by the liver and circulates in the blood. It is involved in breaking down (metabolizing) choline ester drugs. Mutations that cause pseudocholinesterase deficiency either impair the function or production of butyrylcholinesterase. This impairs the body's ability to effectively metabolize choline ester drugs, leading to the abnormally prolonged effects of these drugs.^[1]

Acquired pseudocholinesterase deficiency is not inherited and cannot be passed to the next generation. This form of the condition is caused by impairment of the enzyme's function due to factors such as kidney or liver disease, malnutrition, major burns, cancer, or certain drugs.^[1]^[2]

Last updated: 9/19/2016

Inheritance Inheritance

Pseudocholinesterase deficiency can be inherited or acquired.

The inherited form is autosomal recessive.^[1] This means that to be affected, a person must have a mutation in both copies of the responsible gene (BCHE) in each cell. Affected people inherit one mutated copy of the gene from each parent, who is referred to as a carrier. Carriers of an autosomal recessive condition typically do not have any signs or symptoms (they are unaffected). When 2 carriers of an autosomal recessive condition have children, each child has a:

25% chance to be affected
50% chance to be an unaffected carrier like each parent
25% chance to be unaffected and not a carrier

In some cases, carriers of BCHE gene mutations take longer than usual to clear choline ester drugs from the body - but not as long as those with two mutated copies of the gene.^[1]

Acquired pseudocholinesterase deficiency is not inherited, occurring due to illness, injury, or certain medications.

Last updated: 9/19/2016

Diagnosis Diagnosis

Pseudocholinesterase deficiency often is first suspected after an episode of prolonged respiratory paralysis following general anesthesia. The diagnosis is confirmed by a blood test that measures pseudocholinesterase enzyme activity.^[2]

People with pseudocholinesterase deficiency should warn their relatives to be tested before surgery since the condition is often inherited. People who have relatives who have died for unknown reasons during surgery should be screened for the deficiency prior to undergoing surgery.^[3]

Last updated: 9/19/2016

Treatment Treatment

People with known pseudocholinesterase deficiency should avoid exposure to sources of choline esters. Treatment of prolonged respiratory paralysis following surgery often involves mechanical ventilatory support until the paralysis resolves on its own. In most cases, recovery happens without the need for medical assistance.^[4]^[2]

Last updated: 9/19/2016

Living With Living With

Living with a genetic or rare disease can impact the daily lives of patients and families. These resources can help families navigate various aspects of living with a rare disease.

Genetics Resources

To find a medical professional who specializes in genetics, you can ask your doctor for a referral or you can search for one yourself. Online directories are provided by GeneTests, the American College of Medical Genetics, and the National Society of Genetic Counselors. If you need additional help, contact a GARD Information Specialist. You can also learn more about genetic consultations from Genetics Home Reference.

Learn More Learn More

These resources provide more information about this condition or associated symptoms. The in-depth resources contain medical and scientific language that may be hard to understand. You may want to review these resources with a medical professional.

Where to Start

Genetics Home Reference (GHR) contains information on Pseudocholinesterase deficiency. This website is maintained by the National Library of Medicine.
Mayo Clinic has an information page on Pseudocholinesterase deficiency.
MedlinePlus was designed by the National Library of Medicine to help you research your health questions, and it provides more information about this topic.
The National Organization for Rare Disorders (NORD) has a report for patients and families about this condition. NORD is a patient advocacy organization for individuals with rare diseases and the organizations that serve them.

In-Depth Information

Medscape Reference provides information on this topic. You may need to register to view the medical textbook, but registration is free.
The Monarch Initiative brings together data about this condition from humans and other species to help physicians and biomedical researchers. Monarch’s tools are designed to make it easier to compare the signs and symptoms (phenotypes) of different diseases and discover common features. This initiative is a collaboration between several academic institutions across the world and is funded by the National Institutes of Health. Visit the website to explore the biology of this condition.
Online Mendelian Inheritance in Man (OMIM) is a catalog of human genes and genetic disorders. Each entry has a summary of related medical articles. It is meant for health care professionals and researchers. OMIM is maintained by Johns Hopkins University School of Medicine.
Orphanet is a European reference portal for information on rare diseases and orphan drugs. Access to this database is free of charge.
PubMed is a searchable database of medical literature and lists journal articles that discuss Pseudocholinesterase deficiency. Click on the link to view a sample search on this topic.

GARD Answers GARD Answers

Questions sent to GARD may be posted here if the information could be helpful to others. We remove all identifying information when posting a question to protect your privacy. If you do not want your question posted, please let us know. Submit a new question

If one has acquired pseudocholinesterase deficiency due to malabsorption/malnutrition, does improvement in nutrition result in reversal of the deficiency (i.e. normalization of anesthesia response)? See answer
Are there any symptoms or effects of pseudocholinesterase deficiency that are not specifically related to anaesthesia, for example in normal daily life? See answer
I am looking for information about pseudocholinesterase deficiency in layman's terms for myself and others. Can you tell me more about this condition? See answer
I was told that I had pseudocholinesterase deficiency after I experienced difficulty in the resumption of breathing following surgery with general anesthesia. Is there a test that can verify this diagnosis? Are my children at risk for this condition? See answer