What Is a Stem Cell Transplant?

A stem cell transplant is when doctors put healthy stem cells into someone's bloodstream to replace their stem cells.

It can take a while to feel better after a stem cell transplant, but the treatment can be very helpful for some illnesses.

What Are Stem Cells?

Stem cells are cells that can develop into many different types of cells. The stem cells used for transplants form blood cells. They become:

  • red blood cells that carry oxygen
  • white blood cells that fight infection
  • platelets that help blood clot

Why Are Stem Cell Transplants Done?

Stem cell transplants can help people with:

Where Do the Stem Cells Come From?

Doctors can get the stem cells from the:

  • bone marrow (this is also called a bone marrow transplant)
  • bloodstream
  • umbilical cord blood after the cord is no longer attached to a newborn baby

A person who provides the stem cells is a donor. For some illnesses, people can be their own donor. Their stem cells are taken out, frozen, and transplanted back later. Other times, someone else donates the stem cells.

When stem cells come from another person, the stem cells must have similar genetic makeup. Usually, a child's brother or sister is a good match. A parent or even an unrelated person sometimes can be a match.

What Can Happen When a Donor Isn't a Good Match?

If the donor stem cells are not a good match (and sometimes even if they are):

  • The body's immune system can attack the donor stem cells. This is called rejection.
  • The transplanted cells can attack the body's cells. This is called graft-versus-host disease.

How Are Stem Cell Transplants Done?

Before a stem cell transplant, doctors place a central line (or central venous catheter). This type of IV (intravenous) line goes into the skin and into a large vein near the heart. A central line can stay in the body longer than a regular IV. It gives the medical team a way to give medicines and collect blood for testing without doing a lot of needle sticks.

Stem cell transplants are done in the hospital. First, the person getting the donated stem cells has high doses of chemotherapy and/or radiation to:

  • kill the unhealthy cells causing the illness
  • weaken their immune system so it doesn't reject the donor stem cells

Then, the person gets the donor stem cells through an intravenous line (IV).

What Happens After the Transplant?

After someone has a stem cell transplant, their body needs time to make new red blood cells, white blood cells, and platelets. During this time, they're at a higher risk for infections, bleeding, and other problems.

Most people stay in the hospital for 3–5 weeks after the transplant. Their medical team will:

  • Do blood tests to see if the transplanted stem cells are making new blood cells.
  • Give medicines to help prevent rejection and graft-versus-host disease.
  • Give medicines to prevent infections.
  • Give transfusions of red blood cells, white blood cells, and platelets.
  • Check that organs (such as the liver and kidneys) are working properly.
  • Treat any problems that happen, such as mouth sores, vomiting, diarrhea, infections, bleeding, rejection, and graft-versus-host disease.
  • Make sure the patient is getting good nutrition.
  • Make sure that all visitors follow infection prevention rules, which include:
    • No sick visitors.
    • All visitors must wash their hands before entering the room.
    • All visitors must wear a mask, gloves, and gown.

How Can Parents Help?

It takes a child's immune system about a year to recover after a stem cell transplant. Until then, kids can get very sick from infections. Even a mild infection, like a cold, can be serious. To help your child avoid infections:

  • Your child, family members, and visitors should wash their hands well and often with antibacterial soap and/or hand sanitizer.
  • Don't let anyone who is sick near your child.
  • Your child should bathe every day with a mild shampoo and soap.

Follow your medical team's instructions for:

  • when your child can go to school or other public places
  • when your child needs to wear a mask
  • what foods are OK for your child
  • if your child can be around pets

What Else Should I Know?

Most kids who have had a stem cell transplant feel better over time after they leave the hospital. It's a lot for a child and family to manage the hospital stay and the recovery period. Find support through other family members, your medical team, a counselor, or social worker. Taking care of yourself will help you take care of your child.

To help your child recover and stay healthy:

  • Take your child to all follow-up doctor visits.
  • Support your child during the physical changes that can happen (such as hair loss and tiredness from chemotherapy and/or radiation).
  • Help your child deal with any loneliness from being away from friends and family during recovery. Help set up Skype, Google Hangouts, or FaceTime so your child can keep in touch.
  • Ask if your child wants to talk to a counselor or social worker to help manage the feelings that may come during recovery.
  • Help your child develop a simple routine of light exercise, meals, and activities like games or reading.

When Should I Call the Doctor?

Call your doctor right away if your child:

  • has a fever of 100.4°F (38.0°C) or higher taken orally (in the mouth) 
  • has a runny nose, cough, or congestion
  • has vomiting or diarrhea
  • has black bowel movements (poops)
  • has easy bruising or bleeding
  • has blood in the pee
  • has a headache, dizziness, or blurred vision
  • coughs up blood or has a nosebleed that won't stop after a few minutes
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