The term leukemia refers to cancers of the white blood cells (also called leukocytes or WBCs). Leukemias, as a group, make up about a quarter of all pediatric cancers. Luckily, with treatment, most children with leukemia will be free of the disease without it coming back.
Leukemias start in the bone marrow — the soft tissue found inside bones that produces blood cells. When a child is diagnosed with leukemia, it’s because the white blood cells in the body are producing abnormally. These cells (also known as blasts) start to crowd out the healthy cells in the bone marrow. Eventually, the healthy cells have no place to go, so they stop producing. When a child's body no longer produces enough healthy white blood cells it can cause anemia, swollen lymph nodes, and other symptoms of leukemia in children.
Leukemia is classified as being either acute (meaning it’s rapidly developing) or chronic (meaning it’s slowly developing). About 98% of pediatric leukemias are acute.
Types of Pediatric Leukemia
Types of leukemia in children include:
Acute lymphoblastic leukemia (ALL): This happens when too many lymphoblasts (a certain type of white blood cell) are produced.
This is the most common type of leukemia, affecting nearly 60% of kids with leukemia.
Acute myelogenous leukemia (AML): This occurs when too many immature white blood cells (called myeloid blasts) are made.
These leukemia cells are abnormal and can’t mature into normal white blood cells.
Chronic myelogenous leukemia (CML): This rare form of pediatric leukemia happens because there are too many mature white blood cells.
Signs and Symptoms of Leukemia in Children
Although the symptoms of leukemia in each individual child can vary, common symptoms of leukemia in children include:
anemia (when the level of healthy red blood cells in the body becomes
bleeding and/or bruising
frequent or reoccurring infections
bone and joint pain
swollen lymph nodes (also called “swollen glands”)
excessive fatigue (more tired than usual)
IMPORTANT NOTE: Instances of the symptoms of leukemia in children listed above, either together or on their own, do not automatically mean that a child has leukemia or any other kind of cancer. Any or all of these symptoms could be a sign of something else.
Diagnosing Leukemia in Children
One of our Nemours pediatric hematologists-oncologists (doctors who treat blood disorders and cancers) will conduct a physical examination on your child to check for symptoms of leukemia in children such as signs of infection, anemia, abnormal bleeding, and swollen lymph nodes.
The doctor will also feel your child's abdomen to see if the liver or spleen is enlarged. We’ll also take a complete medical history by asking about your child’s symptoms, past health, your family's health history, any medications your child is taking, allergies, etc.
After this exam, the doctor will order a CBC (complete blood count) to measure the numbers of white cells, red cells, and platelets in your child's blood. Your child’s blood chemistries will also be checked.
Then, depending on what we find in the exam and blood tests, your child also may need a:
bone marrow biopsy and aspiration (when marrow samples are taken for testing, usually from the back of the hip)
lymph node biopsy (when lymph nodes are removed and examined under a microscope to look for abnormal cells)
lumbar puncture (also called a spinal tap, when a sample of spinal fluid is taken from the lower back and examined for evidence of abnormal cells. This test will show if the leukemia has spread to the brain and spinal cord.)
We know that tests can be scary – for you and your child. Whatever kind of tests your child might need, know that your Nemours pediatric leukemia care team will do everything we can to make the experience as comfortable as possible – physically and emotionally. We’ll give sedation or anesthesia as needed and offer support and guidance at every step.
At Nemours, we know that getting a cancer diagnosis can be very frightening and overwhelming for your whole family. That’s why Nemours’ board-certified pediatric hematologists-oncologists, specialty nurses, cancer researchers, and other cancer experts are focused on helping not only your child, but your family, as well.
From diagnosis to treatment (and beyond) we’ll be here to help guide your family through your pediatric leukemia journey – and to strive and hope, with you, for a better tomorrow.
The complete blood count (CBC) is a common blood test that evaluates the three major types of cells in the blood: red blood cells, white blood cells, and platelets.
Why It's Done
A CBC may be ordered as part of a routine checkup, or if your child is feeling more tired than usual, seems to have an infection, or has unexplained bruising or bleeding.
Red blood cells: The CBC's measurements of red blood cell (RBC) count, hemoglobin (the oxygen-carrying protein in RBCs), and mean (red) cell volume (MCV) provides information about the RBCs, which carry oxygen from the lungs to the rest of the body. These measurements are usually done to test for anemia, a common condition that occurs when the body has insufficient red blood cells.
White blood cells: The white blood cell (WBC) count measures the number of WBCs (also called leukocytes) in the blood. The WBC differential test measures the relative numbers of the different kinds of WBCs in the blood. WBCs, which help the body fight infection, are bigger than red blood cells and there are far fewer of them in the bloodstream. An abnormal WBC count may indicate an infection, inflammation, or other stress in the body. For example, a bacterial infection can cause the WBC count to increase, or decrease, dramatically.
Platelets: The smallest blood cells, platelets play an important role in blood clotting and the prevention of bleeding. When a blood vessel is damaged or cut, platelets clump together and plug the hole until the blood clots. If the platelet count is too low, a person can be in danger of bleeding in any part of the body.
The CBC can also test for loss of blood, abnormalities in the production or destruction of blood cells, acute and chronic infections, allergies, and problems with blood clotting.
No special preparations are needed. Having your child wear a short-sleeve shirt on the day of the test can make things easier for the technician who will be drawing blood.
Not much blood is drawn in a CBC. A health professional will usually draw the blood from a vein. For an infant, the blood may be obtained by puncturing the heel with a small needle (lancet). If the blood is being drawn from a vein, the skin surface is cleaned with antiseptic, and an elastic band (tourniquet) is placed around the upper arm to apply pressure and cause the veins to swell with blood. A needle is inserted into a vein (usually in the arm inside of the elbow or on the back of the hand) and blood is withdrawn and collected in a vial or syringe.
After the procedure, the elastic band is removed. Once the blood has been collected, the needle is removed and the area is covered with cotton or a bandage to stop the bleeding. Collecting blood for this test will only take a few minutes.
What to Expect
Either method (heel sticking or vein withdrawal) of collecting a sample of blood is only temporarily uncomfortable and can feel like a quick pinprick. Afterward, there may be some mild bruising, which should go away in a few days.
Getting the Results
The blood sample will be processed by a machine. Parts of the CBC results can be available in minutes in an emergency, but more commonly the full test results come after a few hours or the next day.
If a CBC test points to anemia, infection, or other concerns, your child's doctor may repeat the test just to be sure. If the second set of test results come back the same, your doctor will likely order further lab tests for your child to determine what's causing the problem and how to treat it.
The CBC test is considered a safe procedure. However, as with many medical tests, there are some problems that can occur with having blood drawn, such as:
fainting or feeling lightheaded
hematoma (blood accumulating under the skin causing a lump or a bruise)
pain associated with multiple punctures to locate a vein
Helping Your Child
Having a blood test is relatively painless. Still, many kids are afraid of needles. Explaining the test in terms your child can understand might help ease some of the fear.
Allow your child to ask the technician any questions he or she might have. Tell your child to try to relax and stay still during the procedure, as tensing muscles and moving can make it harder and more painful to draw blood. It also may help if your child looks away when the needle is being inserted into the skin.
If You Have Questions
If you have questions about the CBC test, contact your doctor.