Infection and Neutropenia During Cancer Treatment

An infection is the invasion and growth of germs in the body, such as bacteria, viruses, yeast, or other fungi. An infection can begin anywhere in the body, may spread throughout the body, and can cause a range of signs.

Some types of cancer and treatments such as chemotherapy may increase your risk of infection. This is because they lower the number of white blood cells, the cells that help your body fight infection. During chemotherapy, there are times in your treatment cycle when the number of a type of white blood cell called neutrophils is particularly low and you are at increased risk of infection. Stress, poor nutrition, and not enough sleep can also weaken the immune system.

You will have blood tests to check for neutropenia—a condition in which there is a low number of neutrophils. Medicine may sometimes be given to help prevent infection or to increase the number of white blood cells.

When your infection-fighting cells are low, everyday germs can be more dangerous—so prevention matters.

Call your healthcare team if you have signs of an infection, which can include:

• fever of about 100.4 to 100.5 degrees F (38 degrees C) or higher—sources word this slightly differently, so use your team's number (see below)
• chills
• cough or sore throat
• diarrhea
• ear pain, headache or sinus pain, or a stiff or sore neck
• skin rash
• sores or white coating in your mouth or on your tongue
• swelling or redness, especially where a catheter enters your body
• urine that is bloody or cloudy, or pain when you urinate

A fever during cancer treatment is a temperature of about 38 degrees Celsius—100.4 to 100.5 degrees Fahrenheit—or higher. Authoritative sources word it a little differently:

• National Cancer Institute: a "fever of 100.5 °F (38 °C) or higher" — its printed 100.5 °F is a conversion slip, since 38 °C is 100.4 °F; act at 100.4 °F (38 °C) — listed as a sign of infection to report to your health care team.
• American Cancer Society: "For people with cancer, a fever is defined as a temperature of 100.4°F (38°C) or higher for at least one hour."
• MedlinePlus (NIH): a "fever of 100.4°F (38°C) or higher."
• The clinical definition of febrile neutropenia: "a single oral temperature greater than or equal to 101 F (38.3 C) or a temperature greater than or equal to 100.4 F (38 C) for at least an hour."

We report each figure as its source publishes it rather than reconciling them. 38.0 degrees C converts to 100.4 degrees F; NCI publishes 100.5, and does not explain the difference. The last entry is a case definition clinicians use, not a threshold for you to act on at home. ACS advises: "Ask your cancer care team what temperature they consider to be a fever. It might be different depending on your situation, but 100.4°F (38°C) is often used." Ask in advance and use your team's number. If your temperature falls between these figures and you are unsure, call—no oncology service minds being called.

Infections during cancer treatment can be life threatening and require urgent medical attention. Be sure to talk with your doctor or nurse before taking any medicine—even aspirin, acetaminophen (such as Tylenol), or ibuprofen (such as Advil)—for a fever. These medicines can lower a fever but may also mask or hide signs of a more serious problem.

Your healthcare team will talk with you about these and other ways to prevent infection:

• Wash your hands often and well. Use soap and warm water to wash your hands well, especially before eating. Have people around you wash their hands well too.
• Stay extra clean. If you have a catheter, keep the area around it clean and dry. Clean your teeth well and check your mouth for sores each day. Clean any scrape or cut well. Let your doctor or nurse know if your bottom is sore or bleeds, as this could raise your risk of infection.
• Avoid germs. Stay away from people who are sick or have a cold. Avoid crowds and people who have just had a live vaccine, such as one for chicken pox, polio, or measles. Follow food safety guidelines—make sure meat, fish, and eggs are well cooked, keep hot foods hot and cold foods cold, and wash or peel raw fruits and vegetables as advised.

Some cancer treatments make it easier to get sick from contaminated food. Handling and preparing food safely can help reduce your risk of foodborne illness. Your healthcare team can point you to food safety tips that fit your situation.

• Call 911 or go to an emergency department if an infection starts to look like sepsis. The CDC lists confusion or disorientation, shortness of breath, a high heart rate or weak pulse, extreme pain or discomfort, clammy or sweaty skin, and fever with shivering or feeling very cold. Sepsis is a life-threatening emergency, and low neutrophils make it move fast.
• Ring your oncology team the minute it happens, at any hour, if your temperature reaches the number they gave you — commonly a temperature of 100.4°F (38°C) or higher — or if you get hard shaking chills even with a normal reading. With neutropenia this is not something to hold until morning. The CDC calls a fever during chemotherapy a medical emergency, and antibiotics are meant to start within about an hour of arrival. Your team can often send you straight to the cancer centre. If you cannot reach them quickly, go to an emergency department and tell them at the door that you are on chemotherapy. Do not take acetaminophen or ibuprofen first to see whether it settles, because that can hide the very sign your team needs.
• Call your care team the same day if the skin around a catheter or port turns red, sore, or swollen, if you have burning when you pass urine or cloudy or bloody urine, or if you develop a cough, sore throat, or a stiff neck while your counts are low.
• Call your care team within a day or two if you notice quieter changes: mouth sores or a white coating on your tongue, a new skin rash, diarrhea, or an ache in an ear or sinus. These can be the first foothold of an infection before a fever appears.

• National Cancer Institute, Infection and Neutropenia During Cancer Treatment: https://www.cancer.gov/about-cancer/treatment/side-effects/infection
• CDC, About Sepsis: https://www.cdc.gov/sepsis/about/index.html
• CDC, Watch Out for Fever: https://www.cdc.gov/cancer-preventing-infections/patients/fever.html