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:

• severe blood or immune system illnesses
• some kinds of cancer
• immune deficiency
• autoimmune diseases such as lupus
• blood disorders (such as thalassemia or sickle cell disease)

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 person'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 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 I Feel Better?

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

• You, family members, and visitors should wash their hands well and often with antibacterial soap and/or hand sanitizer.
• Stay away from anyone who is sick.
• Bathe every day with a mild shampoo and soap.

Follow your medical team's instructions for:

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

What Else Should I Know?

Most teens who have had a stem cell transplant feel better over time after they leave the hospital. Your health care team knows how tough recovery can be, and how important it is to get emotional support. Your doctor, a hospital social worker, or child life specialist can help you get through this difficult time, so be sure to ask.

When Should I Call the Doctor?

You or your parent should call your doctor right away if you:

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