Pyruvate kinase deficiency

Title

Other Names:

Pyruvate kinase deficiency of red cells; Pyruvate kinase deficiency of erythrocytes; PK deficiency

Categories:

Blood Diseases; Congenital and Genetic Diseases; Metabolic disorders

Summary Summary

Pyruvate kinase deficiency is a genetic blood disorder characterized by low levels of an enzyme called pyruvate kinase, which is used by red blood cells. Without pyruvate kinase, red blood cells break down too easily, resulting in low levels of these cells (hemolytic anemia).^[1] The signs and symptoms of the disease may vary greatly from person to person. However, they usually include jaundice, enlargement of the spleen, and mild or severe hemolysis (red cell breakdown), leading to anemia.^[2] In some cases, the problems may first appear while in utero, causing a condition in which abnormal amounts of fluid build up in two or more body areas of the fetus (hydrops fetalis). Newborns may present with prolonged jaundice and anemia. Older children may be pale (due to anemia) and have intermittent episodes of jaundice. Mild cases may escape detection until adulthood.^[1] Although the anemia tends to stabilize in adulthood, episodes of anemia may occur with acute infections, stress, and pregnancy.^[3] Pyruvate kinase deficiency is caused by a mutation in the PKLR gene and is inherited in an autosomal recessive fashion.^[1]^[4] Treatment remains supportive rather than curative.^[3]

Last updated: 1/13/2016

Symptoms Symptoms

The signs and symptoms of pyruvate kinase deficiency may vary greatly from person to person, but usually include the breakdown of red blood cells resulting in hemolytic anemia, a yellowing of the whites of the eyes (icterus), fatigue, lethargy, recurrent gallstones, jaundice, and pale skin (pallor).^[1]

In more severe cases, the first signs and symptoms may appear in utero in the form of hydrops fetalis, a condition in which abnormal amounts of fluid build up in two or more body areas of the fetus. Newborns may present with prolonged jaundice and anemia. Older children may be pale (due to anemia) and have intermittent episodes of jaundice. Mild cases may escape detection until adulthood.^[1] Although the anemia tends to stabilize in adulthood, episodes of anemia may occur with acute infections, stress, and pregnancy.^[3]

Last updated: 1/13/2016

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)
Intrauterine growth retardation	5%
Nonimmune hydrops fetalis	5%
Abnormality of the amniotic fluid	-
Autosomal recessive inheritance	-
Cholecystitis	-
Cholelithiasis	-
Chronic hemolytic anemia	-
Increased red cell osmotic fragility	-
Jaundice	-
Reticulocytosis	-
Splenomegaly	-
Unconjugated hyperbilirubinemia	-

Last updated: 9/1/2016

Cause Cause

In most cases, pyruvate kinase deficiency is caused by mutations in the PKLR gene.^[1] More than 100 different mutation in the PKLR gene have been detected. Medical conditions, such as acute leukemia, preleukemia, and refractory sideroblastic anemia, as well as complications from chemotherapy, can cause an acquired pyruvate kinase deficiency. This type is more common and milder than the hereditary type.^[5]

Last updated: 7/18/2011

Inheritance Inheritance

Pyruvate kinase deficiency is inherited in an autosomal recessive fashion, which means that a child must inherit a gene with a disease-causing mutation from both parents to develop the disorder. The gene that causes pyruvate kinase deficiency is called the PKLR gene that is located on chromosome 1q21.^[4] Although the inheritance is clinically autosomal recessive, most affected individuals are compound heterozygous for two different mutant alleles. It is estimated that approximatly 1 in 100 people carry one copy of a disease-causing mutation in the PKLR gene.^[5] Carriers of one non-working PKLR gene usually have moderatly reduced levels of pyruvate kinase activity but do not develop clinical symptoms. It is possible that carriers of a mutant pyruvate kinase genemay have a protective advantage against malaria in areas where the disease is endemic.^[6]

Last updated: 7/18/2011

Diagnosis Diagnosis

Yes. GeneTests lists laboratories offering clinical genetic testing for this condition. Clinical genetic tests are ordered to help diagnose an affected person or other family members and to aid in decisions regarding medical care or reproductive issues. We recommend that you talk to your health care provider or a genetic professional to learn more about your testing options.

Last updated: 7/18/2011

Testing Resources

The Genetic Testing Registry (GTR) provides information about the genetic tests for this condition. The intended audience for the GTR is health care providers and researchers. Patients and consumers with specific questions about a genetic test should contact a health care provider or a genetics professional.

Treatment Treatment

Mild cases require no treatment. People with severe anemia may need blood transfusions. In newborns with dangerous levels of jaundice, a health care provider may recommend an exchange transfusion. Surgical removal of the spleen (splenectomy) may also be necessary to help reduce the destruction of red blood cells. However, this does not help in all cases. With small children, this is delayed as long as possible to allow the immune system to mature. Other treatment is symptomatic and supportive. Someone who had a splenectomy should receive the pneumococcal vaccine at recommended intervals. They also should receive preventive antibiotics until age 5.^[2]^[1]

An article from eMedicine Journal provides additional information on treatment for pyruvate kinase deficiency at the following link. You may need to register to view the article, but registration is free.
http://emedicine.medscape.com/article/125096-treatment#showall

Last updated: 7/18/2011

Prognosis Prognosis

The prognosis varies. Some people may have few or no symtpoms, while others have severe symtpoms. People who have mild to moderate forms of pyruvate kinase deficiency tend to do very well long term. People with more severe forms of the disease are mostly symptomatic during early childhood. Following early childhood, the condition is much better tolerated.^[5] Some people may experience complications such as gallstones and stroke. Severe pneumococcal disease is a possible complication after splenectomy.^[5]^[1]

Last updated: 7/18/2011

Statistics Statistics

It is estimated that 1 in 20,000 people world-wide have pyruvate kinase deficiency. A particularly high frequecy exists among the Pennsylvania Amish, in whom the disorder can be traced to a single immigrant couple.^[7]^[5]

Last updated: 5/13/2016

Organizations Organizations

Nonprofit support and advocacy groups bring together patients, families, medical professionals, and researchers. These groups often raise awareness, provide support, and develop patient-centered information. Many are the driving force behind research for better treatments and possible cures. They can direct people to research, resources, and services. Many groups also have experts who serve as medical advisors. Visit their website or contact them to learn about the services they offer. Inclusion on this list is not an endorsement by GARD. Suggest an organization to add.

Organizations Supporting this Disease

European Network for Rare and Congenital Anaemias (ENERCA)
University of Barcelona
Red Cell Pathology Unit
C/Villarroel, 170 - 08036
Barcelona
España
Telephone: (34) 93 451 5950
Fax: (34) 93 227 1764
E-mail: enerca@enerca.org
Website: http://www.enerca.org

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 Pyruvate kinase deficiency. This website is maintained by the National Library of Medicine.
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 Pyruvate kinase deficiency. Click on the link to view a sample search on this topic.

Selected Full-Text Journal Articles

Durand PM, Coetzer TL. Pyruvate kinase deficiency protects against malaria in humans. Haematologica. 2008 Jun;93(6):939-40. Epub 2008 May 6.

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

My first child has the gene responsible for pyruvate kinase deficiency. Are there ways to monitor for this condition prenatally? Where can we access genetic testing for pyruvate kinase deficiency? See answer
My granddaughter has been diagnosed with pyruvate kinase deficiency. I have many questions about this condition, including how many people may be affected and if it is more common in any particular population. Any information you could provide would be helpful. See answer
My son was diagnosed with pyruvate kinase deficiency when he was a baby. My husband and I were tested and are negative for being carriers. Could you tell me what else could cause pyruvate kinase deficiency? See answer
My child, who is under 6 months old, has pyruvate kinase deficiency. What impact will this diagnosis have for her in the future? See answer

References References

Haldeman-Englert C. Pyruvate kinase deficiency. MedlinePlus Encyclopedia. 2/3/2014; http://www.nlm.nih.gov/medlineplus/ency/article/001197.htm.
Pyruvate Kinase Deficiency. National Organization for Rare Disorders (NORD). 2005; http://www.rarediseases.org/rare-disease-information/rare-diseases/byID/465/viewAbstract. Accessed 7/18/2011.
Grace RF, Zanella A, Neufeld EJ, Morton DH, Eber S, Yaish H, Glader B. Erythrocyte pyruvate kinase deficiency: 2015 status report. Am J Hematol. 2015 Sep; 90(9):825-30.
Zanella A, Fermo E, Bianchi P, Chiarelli LR, Valentini G. Pyruvate kinase deficiency: the genotype-phenotype association.. Blood Rev. 2007; http://www.ncbi.nlm.nih.gov/pubmed/17360088. Accessed 7/18/2011.
Hassan M Yaish, MD. Pyruvate Kinase Deficiency. Medscape. April 28, 2014; http://emedicine.medscape.com/article/2196589-overview.
Durand PM, Coetzer TL. Pyruvate kinase deficiency protects against. Haematologica. June 2008; http://www.haematologica.org/cgi/reprint/haematol.12450v1. Accessed 7/18/2011.
Glader Bertil E. Chapter 76. Other Hereditary Red Blood Cell Disorders. In: Rimoin DL, Connor JM, Pyeritz RE, Korf BR, eds. Emery and Rimoin's: Principles and Practices of Medical Genetics. Vol 2. 5th ed. Philadelphia, PA: Churchill Livingstone; 2007: 1675. .