Pyruvate kinase deficiencyPK deficiency; PKD
Pyruvate kinase deficiency is an inherited lack of the enzyme pyruvate kinase, which is used by red blood cells. Without this enzyme, red blood cells break down too easily, resulting in a low level of these cells (hemolytic anemia).
Enzymes are complex proteins that cause a specific chemical change in all parts of the body. For example, they can help break down the foods we eat ...Read Article Now Book Mark Article
Anemia is a condition in which the body does not have enough healthy red blood cells. Red blood cells provide oxygen to body tissues. Normally, red ...Read Article Now Book Mark Article
Pyruvate kinase deficiency (PKD) is passed down as an autosomal recessive trait. This means that a child must receive a non-working gene from each parent to develop the disorder.
Autosomal recessive is one of several ways that a trait, disorder, or disease can be passed down through families. An autosomal recessive disorder me...Read Article Now Book Mark Article
There are many different types of enzyme-related defects of the red blood cell that can cause hemolytic anemia. PKD is the second most common cause, after glucose-6-phosphate dehydrogenase (G6PD) deficiency.
Glucose-6-phosphate dehydrogenase (G6PD) deficiency is a condition in which red blood cells break down when the body is exposed to certain drugs or t...Read Article Now Book Mark Article
PKD is found in people of all ethnic backgrounds. But, certain populations, such as the Amish, are more likely to develop the condition.
Symptoms of PKD include:
- Low count of healthy red blood cells (anemia)
- Swelling of the spleen (splenomegaly)
- Yellow color of the skin, mucous membranes, or white part of the eyes (jaundice)
- Neurologic condition, called kernicterus, that affects the brain
- Fatigue, lethargy
- Pale skin (pallor)
- In infants, not gaining weight and growing as expected (failure to thrive)
- Gallstones, usually in the teens and older
Exams and Tests
The health care provider will perform a physical exam and ask about and check for symptoms such as an enlarged spleen. If PKD is suspected, tests that will likely be ordered include:
Splenomegaly is a larger-than-normal spleen. The spleen is an organ in the upper left part of the belly.Read Article Now Book Mark Article
- Bilirubin in the blood
- Genetic testing for mutation in the pyruvate kinase gene
- Haptoglobin blood test
- Osmotic fragility
- Pyruvate kinase activity
- Stool urobilinogen
People with severe anemia may need blood transfusions. Removing the spleen (splenectomy) may help reduce the destruction of red blood cells. But, this does not help in all cases. In newborns with a dangerous level of jaundice, the provider may recommend an exchange transfusion. This procedure involves slowly removing the infant's blood and replacing it with fresh donor blood or plasma.
Spleen removal is surgery to remove a diseased or damaged spleen. This surgery is called splenectomy. The spleen is in the upper part of the belly, ...Read Article Now Book Mark Article
Exchange transfusion is a potentially life-saving procedure that is done to counteract the effects of serious jaundice or changes in the blood due to...Read Article Now Book Mark Article
Someone who had a splenectomy should receive the pneumococcal vaccine at recommended intervals. They also should receive preventive antibiotics until age 5.
All content below is taken in its entirety from the CDC Information Statement (VIS): www. cdc. gov/vaccines/hcp/vis/vis-statements/pcv. htmlRead Article Now Book Mark Article
More information and support for people with PKD condition and their families can be found at:
- National Library of Medicine - MedlinePlus -- medlineplus.gov/genetics/condition/pyruvate-kinase-deficiency/
- National Organization for Rare Disorders -- rarediseases.org/rare-diseases/pyruvate-kinase-deficiency/
- NIH Genetic and Rare Diseases Information Center -- rarediseases.info.nih.gov/diseases/7514/pyruvate-kinase-deficiency
The outcome varies. Some people have few or no symptoms. Others have severe symptoms. Treatment can usually make symptoms less severe.
Gallstones are a common problem. They are made of too much bilirubin, which is produced during hemolytic anemia. Severe pneumococcal disease is a possible complication after splenectomy.
When to Contact a Medical Professional
See your provider if:
- You have jaundice or anemia.
- You have a family history of this disorder and are planning to have children. Genetic counseling can help you know how likely it will be that your child would have PKD. You can also learn about tests that check for genetic disorders, such as PKD, so that you can decide if you'd like to have these tests.
Brandow AM. Pyruvate kinase deficiency. In: Kliegman RM, St. Geme JW, Blum NJ, Shah SS, Tasker RC, Wilson KM, eds. Nelson Textbook of Pediatrics. 21st ed. Philadelphia, PA: Elsevier; 2020:chap 490.
Gallagher PG. Hemolytic anemias: red blood cell membrane and metabolic defects. In: Goldman L, Schafer AI, eds. Goldman-Cecil Medicine. 26th ed. Philadelphia, PA: Elsevier; 2020:chap 152.
Review Date: 11/1/2021
Reviewed By: Anna C. Edens Hurst, MD, MS, Associate Professor in Medical Genetics, The University of Alabama at Birmingham, Birmingham, AL. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.