Infection and Multiple Myeloma

Medically Reviewed by Melinda Ratini, MS, DO on June 29, 2022
6 min read

When you have multiple myeloma, infections are something you’ll need to watch out for. The disease and its treatment make infections more likely. If you get an infection, it’s also more likely to get worse because your immune system won’t work as well to fight it.

One study found that 45% of early deaths in multiple myeloma happened because of infections – not the cancer itself. So it’s important for you to know what steps to take to protect yourself against infection.

Multiple myeloma is a cancer that happens in certain white blood cells. Those cells, called plasma cells, normally help you fight infections. But when you have myeloma, those cells don’t act the way they should. Instead of making antibodies to fight infections, they make other abnormal proteins. They also build up in your bones and crowd out other cells your body needs.

Because of this, frequent infections are a common symptom of multiple myeloma. If you have multiple myeloma, you might not need treatment right away. Your doctor might watch to see how it’s growing and if you’re having symptoms. When it’s time that you do need treatment, the drugs that help to fight the cancer can leave you even more prone to getting infections.

As myeloma treatments have gotten better, more people with myeloma are living longer. Multiple myeloma today has become a chronic condition. You may get better for a while and then relapse. Your immune system may get weaker over time. So finding ways to manage any problems with your immune system and your risk for infection is key to doing well.

Your doctor will use tests to find out what stage or how advanced the cancer is. For multiple myeloma, one of the most important things your doctor will want to find out is if you’re having symptoms. If you aren’t having symptoms, you might not need treatment right away.

Infections aren’t one of the main symptoms doctors use to decide if you need treatment. But it’s still an important symptom. If you’ve had more than two episodes of serious bacterial infections in the last year, it may be a sign that you’ll need treatment. But your doctor will look at several other signs, too.

While your risk of infection can increase over time, you’ll already be at more risk of infection in the first year. One study found that people with myeloma got infections with bacteria seven times more often than people without myeloma. In the first year, the risk was even more. You’re also more likely to get viral infections. Studies suggest that your risk of viral infection in the first year may be increased by up to 18 times.

Some infections that are more likely when you have myeloma include:

  • Infection in the fluid around your brain and spinal cord (meningitis)
  • Blood poisoning by bacteria (sepsis or septicemia)
  • Infection in one or both of your lungs (pneumonia)
  • Infection in your bones (osteomyelitis)
  • Infection in deep layers of your skin (cellulitis)
  • Infection in your kidneys (pyelonephritis)

Multiple myeloma happens most when you’re 60 and up. Few people with myeloma are under 40, but it does happen. One study found that infections in people with myeloma are happening more in recent years than they used to in people of all ages. The researchers think this is a sign that new treatments come with added infection risk.

They found that the risk has gone up both in people with myeloma who were older and younger. Younger people with myeloma may more often get newer treatments or stem cell transplants. Doctors don’t know for sure, but these treatments might help to explain the increase in infections in younger people with myeloma. Ask your doctor about the risk of infection related to any treatment you’re receiving for your myeloma.

If you have an infection from bacteria, your doctor will need to treat it with antibiotics as soon as they can. You’ll probably have a fever. Your doctor might also have you take antibiotics regularly to make it less likely you’ll get an infection in the first place. One antibiotic they might use for this is trimethoprim-sulfamethoxazole (Bactrim or Septra).

If you get infections a lot, you might also take penicillin every day. Some people with multiple myeloma also get infusions with antibodies that are found in the plasma from plasma donors. These infusions are called gamma globulin. Usually you won’t need this, but you could ask your doctor about it if you think you’re getting infections too much.

You can take other steps to make infections less likely to happen. This will include getting your vaccines. You should get your regular flu vaccine to help keep you from getting influenza. The pneumococcal vaccine will lower your risks for pneumonia.

Doctors also recommend that all people with myeloma get vaccinated against COVID-19. You should follow guidance for people with a compromised immune system. This means you’ll need more doses of the vaccine to help you stay more protected. Ask your doctor if there are any other vaccines you should get.

You can take lots of other steps to help lower your infection risk. These include:

  • Wash your hands a lot with soap and water. Wash them for at least 20 seconds each time you do.
  • Carry alcohol-based sanitizer to keep your hands clean when you can’t wash them with soap and water.
  • Don’t touch your face when your hands haven’t just been washed.
  • Be careful about spending time with anyone who might be sick.
  • Keep 6 feet between you and other people when you are out in public places or around a lot of people.
  • Don’t go to parties or other large social gatherings.
  • Wear a well-fitting mask that covers your mouth and nose when you’re in a place with other people indoors.
  • Don’t travel when you can help it, especially in an airplane or cruise ship.
  • Avoid places where you know viral illnesses including COVID-19 are spreading a lot.
  • Drink lots of water and exercise.

When you have multiple myeloma, it’s a good idea to watch for any signs of infection or illness. Call your doctor if you get a fever, especially if you're getting chemotherapy to treat cancer. Infections can have lots of symptoms, but sometimes a fever is the only one.

Other signs of an infection may include:

  • Chills or sweats
  • Coughing
  • Sore throat
  • Trouble breathing
  • Congestion
  • Stiff neck
  • Pain or burning when you pee
  • Vaginal discharge or irritation
  • Peeing more often
  • Redness, soreness, or swelling in any part of your body
  • Diarrhea
  • Throwing up
  • Belly pain
  • Any new pain

An infection when you have multiple myeloma, whether you’re in treatment or not, can be fatal. Many people with myeloma don’t die from cancer but from an infection. To help you catch it quickly if you have an infection, follow these steps:

  • Take your temperature if you don’t feel well or think you may be warm.
  • Always have a thermometer with you so you can check your temperature.
  • Call your doctor if you have a fever or temperature of at least 100.4 F or any other new symptom that could mean an infection.
  • Ask your doctor how high your risk is based on your cancer stage or other factors and what steps you should take to protect yourself.
  • Carry your doctor’s contact information with you and know how to reach someone quickly at any time.
  • If you decide you need to go to an emergency room or other clinic, tell the doctor and others at the clinic about your multiple myeloma and infection risk.