Sepsis, infection, and cancer

Sepsis is a serious complication of an infection that can be life threatening. 

Sepsis happens when your body has an overwhelming response to an infection. Your immune system Open a glossary item reacts abnormally to the infection and starts to attack your body organs. This can lead to organ failure if not treated in time. 

You may also hear sepsis called blood poisoning or septicaemia. 

Ask your healthcare team about your risk of infection and sepsis. Make sure you and your friends and family know what symptoms to look out for.

Treating an infection early can stop it becoming a more serious problem. This reduces the risk of infection developing into sepsis.

Symptoms of an infection

There are several symptoms you might have when you have an infection.  Call your 24 hour advice line straight away if you have any of these:

  • feeling generally unwell – not able to get out of bed
  • a change in your temperature – 37.5°C or higher or below 36°C
  • flu-like symptoms – feeling cold and shivery, headaches, and aching muscles
  • coughing up green phlegm
  • a sore throat or sore mouth
  • a throbbing, painful tooth
  • pain having a wee, going more often or cloudy or foul-smelling wee
  • diarrhoea – 4 or more loose, watery bowel movements in 24 hours
  • skin changes – redness, feeling hot, swelling or pain
  • a fast heartbeat
  • feeling dizzy or faint
  • being sick (vomiting)
  • a headache
  • pain, redness, discharge, swelling or heat at the site of a wound or intravenous line such as a central line or PICC line
  • pain anywhere in your body that was not there before your treatment

Remember, it is just as important to report a very low temperature as it is a high temperature. Do still contact your advice line even if you don’t have a change in temperature, but have other symptoms.

Symptoms of sepsis

The following symptoms could be due to sepsis. Call 999 or go to your local Accident and Emergency (A&E) immediately if you have any of the following symptoms:

  • Slurred speech or confusion
  • Extreme shivering or muscle pain
  • Passing no urine (in a day)
  • Severe breathlessness
  • It feels like you’re going to die  
  • Skin mottled or discoloured

Can I get sepsis with cancer treatment?

People having treatment for cancer are at risk of developing sepsis. This is because some cancer treatments weaken the immune system. Our immune system is important for fighting infection. So, having a weak immune system means our body can’t fight infections as well as it should.

Can I get sepsis if I’m not having treatment for my cancer?

It is still possible to develop sepsis, even if you are not having any treatment for your cancer. People might pick up infections for other reasons. For example, they might have a chest infection or urine infection. Some types of cancer, such as leukaemia, can weaken your immune system. 

Cancer treatments that can increase the risk of sepsis

You are most at risk of developing sepsis if you have:

  • chemotherapy, or
  • radiotherapy with chemotherapy (chemoradiotherapy)

You can get sepsis with other cancer treatments, but the risk is lower. These treatments include:

  • surgery    
  • a procedure involving a cut in the skin, for example, a biopsy Open a glossary item or having a central line Open a glossary item 
  • radiotherapy - this is more likely with radiotherapy that includes areas of bone marrow Open a glossary item
  • targeted cancer drugs
  • immunotherapy

Your healthcare team follow strict guidelines to help prevent infections during your treatment.

Neutropenic sepsis

There are different types of white blood cells. Neutrophils are a particular type of white blood cell that have an important role in fighting infection. Having a very low number of neutrophils is called neutropenia. 

If you have neutropenia you are at risk of developing a serious condition called neutropenic sepsis. This can be life threatening. This is more likely to happen with chemotherapy and other treatments that lower the immune system. 

The number of neutrophils usually drops after treatment. For example, it can be at its lowest around 7 to 10 days after your chemotherapy. But this can vary depending on the drugs you have, how often you have them, and the dose. You have blood tests to check for this at regular points during your treatment or if you are unwell.

The neutrophils usually go back to normal before you start your next course of treatment. But they tend to drop in the same way with each course of treatment you have.

Remember you can get an infection at any time during your treatment. So, it’s important to be aware of the symptoms.   

Assessment and treatment

When you call your advice line, you will speak to a doctor or nurse. They will ask questions about your symptoms and treatment and tell you what you need to do. They may ask you to go to hospital straight away, or they may suggest ways you can relieve your symptoms at home.

If you need to go to hospital, your nurses and doctors work quickly to find out exactly what is wrong. This is important so they treat the infection immediately. 

You will have blood tests and your nurse will regularly check your temperature, pulse, blood pressure, oxygen saturation levels, and how well you are breathing. They will also check how much wee you are passing. Any wounds you have are checked and swabbed. 

Other tests you might have include:

  • a chest x-ray
  • an x-ray of your tummy (abdomen) and pelvis
  • testing a sample of wee
  • a throat swab if your throat is sore

You usually have oxygen through a mask or nasal tubes. And you will have fluids and antibiotics through a tube into your vein (intravenously).

You might be referred for assessment by a specialist team who are used to treating sepsis.

Not everyone who has an infection will go on to develop sepsis. After some tests, your healthcare team may decide that your risk of developing sepsis is low. You may be able to go home. You may be given some antibiotic tablets to take. Contact your advice line again if you become more unwell or you are not getting better.

Can I reduce my risk of infection?

You can’t always prevent an infection and you can’t stop your neutrophil levels from dropping while you are having treatment. The most important thing you can do is contact your advice line, or depending on your symptoms – call 999 or go to A&E. But there are things you can do to help yourself before and during your treatment. 

Things you can do to help yourself before treatment:

  • Have a dental check.
  • Buy a thermometer and make sure you and your friends and family know how to use it.
  • Talk to your healthcare team about vaccines you should have. For example, the flu vaccine and Coronavirus (COVID-19) vaccine.
  • Make sure you and your family and friends are familiar with the symptoms of an infection and sepsis. Let everyone know about the advice line.

Your hospital may give you an alert card explaining the symptoms and what to do, or you can get them from The UK Sepsis Trust.

Things you can do to help yourself during treatment:

  • Try to avoid people who are unwell or have an infection. For example, people with chest infections, diarrhoea, and chicken pox.
  • Brush your teeth with a soft toothbrush at least twice a day and preferably after every meal and at bedtime.
  • Tell your doctor if you have any ulcers or pain anywhere in your mouth.
  • Wash your hands before eating or handling food, after using the toilet, and after contact with animals.
  • Protect your skin from scratches. You can do this by wearing gloves and keeping your arms and legs covered when you are gardening. If you do cut or graze your skin, wash the area thoroughly with warm water and soap. You can put antiseptic cream over the area and cover it with a plaster. 
  • Store, prepare, and cook food following the correct instructions.

Don’t be afraid to live your life as normal. You do not need to stop seeing family and friends unless they have an infection or feel unwell. You don't need to avoid crowded places unless specifically advised to do so by your healthcare team.

  • The Sepsis Manual (6th edition)

    Dr Ron Daniels and Professor Tim Nutbeam

    United Kingdom Sepsis Trust, 2022

  • The third international consensus definitions for sepsis and septic shock (Sepsis-3)

    M Singer and others

    The Journal of the American Medical Association 2016. Volume315, Issue 8, Pages 801-810

  • Sepsis: recognition, diagnosis and early management

    National Institute for Health and Care Excellence (NICE), July 2016. Last updated September 2017

  • BMJ Best Practice Sepsis in Adults  
    T Aliabadi-Oglesby and others
    BMJ Publishing Group Ltd, last updated January 2023

Last reviewed: 
07 Aug 2023
Next review due: 
07 Aug 2026

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