Pyruvate kinase deficiency is a condition in which red blood cells break down faster
than they should. This can lead to anemia
(not enough red blood cells).
Most people with pyruvate kinase deficiency lead a healthy life. Symptoms often
get better in adulthood and happen only when the body is under stress (for example,
from a viral illness or during pregnancy).
What Happens in Pyruvate Kinase Deficiency?
Pyruvate kinase (pie-ROO-vate KYE-nace) is an enzyme. Enzymes are chemicals that
do specific jobs in the body. People with pyruvate kinase deficiency do not have enough
of this enzyme.
Red blood cells carry oxygen to all parts of the body. Pyruvate kinase helps make
the energy they need to do this. Without enough pyruvate kinase, the red blood cells
don't work as they should and break down too quickly.
What Are the Signs & Symptoms of Pyruvate Kinase Deficiency?
Symptoms of pyruvate kinase deficiency range from mild to severe and may start
at any age.
Many symptoms are from the anemia, such as:
a fast heartbeat
trouble keeping up with other children during play or exercise
The anemia in pyruvate kinase deficiency can get worse when the body is under stress.
If it becomes severe, it's called an aplastic crisis.
Other signs of pyruvate kinase deficiency include:
an enlarged spleen.
The spleen breaks down abnormal blood cells, so it works harder in people with pyruvate
kinase deficiency and gets bigger.
problems from the buildup of substances made when red blood cells break down,
dark-colored pee (urine)
yellowing of the whites of the eyes and skin (jaundice)
Iron also can build up in the body. This can happen because:
The body absorbs more iron
when someone is anemic.
Blood transfusions, which are a treatment for pyruvate
kinase deficiency, put extra iron into the body.
What Causes Pyruvate Kinase Deficiency?
A gene change (mutation) causes most cases of pyruvate kinase deficiency. Many
different gene changes can lead to the condition. Symptoms can be very mild or more
severe depending on which one caused it.
Families can talk to a genetic
counselor to find out more about how pyruvate kinase deficiency runs in families.
Children who have mild symptoms usually don't need treatment. Kids with moderate
to severe symptoms will need treatment. They're usually cared for by a pediatric hematologist
(a doctor who treats children's blood problems).
Treatment may include:
for jaundice: ultraviolet (UV) light (phototherapy) or replacing the baby's blood
with donated blood
for anemia: blood transfusions, folic acid, and B vitamins
for iron buildup: iron chelation (key-LAY-shun), in which medicines send the extra
iron out of the body in pee
to help prevent red blood cell breakdown: removing part of or the entire spleen
to help prevent gallstones: removing the gallbladder
How Can Parents Help?
Pyruvate kinase deficiency is a lifelong condition. But many people have no symptoms,
especially in adulthood. If needed, treatments can help those with symptoms live an
active and healthy life.
To help your child:
Go to all medical appointments.
Know when to call the doctor, including if your child shows signs of anemia like
paleness or getting tired very easily.
Do not give your child aspirin. It's not safe for kids and can make symptoms of
pyruvate kinase deficiency worse.
Follow all instructions if your child had a splenectomy, including:
avoiding contact sports
wearing a spleen guard
getting vaccines on time
taking any recommended antibiotics
calling the doctor when your child is sick or has a fever