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Sepsis, blood poisoning or septicaemia

Sepsis is a life-threatening illness caused when the body is overcome by infection.

This condition can develop either as a result of the body's own defence system, or from toxic substances made by the infecting agent (such as a bacteria, virus or fungus).

There are three stages of sepsis:

  • Sepsis - infection is present, or probably present, and there are symptoms including high or low temperature, fast heart rate, fast breathing rate.
  • Severe sepsis - when the infection starts to interfere with the functioning of organs of the body.
  • Septic shock - symptoms and signs of severe sepsis, plus blood pressure drops to dangerous levels despite appropriate treatment, and organs are prevented from getting enough oxygenated blood.


Symptoms of sepsis include:

  • Fever, but sometimes the body temperature may be normal or even low
  • Chills and severe shaking
  • Heart beating very fast, sometimes with rapid breathing

Symptoms of severe sepsis or septic shock include:

  • Confusion
  • Disorientation
  • Agitation
  • Dizziness, particularly when standing up
  • Decreased urination
  • Diarrhoea
  • Nausea and vomiting
  • Skin is cold, pale and clammy
  • Rash - some people with septicaemia develop a reddish discolouration or small dark red dots throughout the body
  • Joint pain in the wrists, elbows, back, hips, knees and ankles.

People at risk of sepsis

  • People whose immune system (the body's defence against microbes) is not functioning well because of an illness (such as cancer or AIDS) or because of medical treatment (such as chemotherapy for cancer or steroids for a number of medical conditions) that weakens the immune system are more prone to develop sepsis. It is important to remember that even healthy people can develop from sepsis.
  • Because their immune systems are not completely developed, very young babies may get sepsis if they become infected and are not treated in a timely manner. Often, if they develop signs of an infection such as fever, infants have to receive antibiotics and be admitted to hospital. Sepsis in the very young is often more difficult to diagnose because the typical signs of sepsis (fever, changes in behaviour) may not be present or may be more difficult to identify.
  • Elderly people, especially those with other conditions, such as diabetes, may be at increased risk as well.
  • The number of people developing sepsis in the UK appears to be increasing with more than 44,000 deaths due to sepsis in the UK each year. Because of our ageing population, the number of elderly people with weak immune systems has also grown.
  • Finally, because of the increased and often inappropriate use of antibiotics to treat illnesses caused by viruses and not bacteria, many strains of bacteria have become resistant to antibiotics, making the treatment of sepsis more difficult in some cases.


Many different microbes can cause sepsis. Although bacteria are most commonly the cause, viruses and fungi can also cause sepsis. Infections in the lungs ( pneumonia), bladder and kidneys ( urinary tract infections), skin ( cellulitis), abdomen (such as appendicitis), and other organs (such as meningitis) can spread and lead to sepsis. Infections that develop after surgery can also lead to sepsis.

WebMD Medical Reference

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