Overview

Sepsis is a rare but serious complication of an infection.

Without quick treatment, sepsis can lead to multiple organ failure and death.

Title
sepsis

Causes

Sepsis can be triggered by an infection in any part of the body. The most common sites of infection leading to sepsis are the lungs, urinary tract, tummy (abdomen) and pelvis.

Sepsis may develop when you're already in hospital. For example, you're more likely to develop sepsis if:

  • you've recently had surgery
  • you've had a urinary catheter fitted
  • you have to stay in hospital for a long time
Sources of infection

Types of infection associated with sepsis include:

Sometimes the specific infection and source of sepsis can't be identified.

What causes the symptoms of sepsis?

Usually, your immune system keeps an infection limited to one place. This is known as a localised infection.

Your body produces white blood cells, which travel to the site of the infection to destroy the germs causing infection.

A series of biological processes occur, such as tissue swelling, which helps fight the infection and prevents it spreading. This process is known as inflammation.

If your immune system is weak or an infection is particularly severe, it can quickly spread through the blood into other parts of the body. This causes the immune system to go into overdrive, and the inflammation affects the entire body.

This can cause more problems than the initial infection, as widespread inflammation damages tissue and interferes with blood flow.

The interruption in blood flow leads to a dangerous drop in blood pressure, which stops oxygen reaching your organs and tissues.

Diagnosis
Tests to diagnose sepsis

Sepsis is often diagnosed based on simple measurements such as your temperature, heart rate and breathing rate. You may need to give a blood test.

Other tests can help determine the type of infection, where it's located and which body functions have been affected. These include:

  • urine or stool samples
  • a wound culture – where a small sample of tissue, skin or fluid is taken from the affected area for testing
  • respiratory secretion testing – taking a sample of saliva, phlegm or mucus
  • blood pressure tests
  • imaging studies – such as an X-ray, ultrasound scan or computerised tomography (CT) scan
Treatment

Treatment for sepsis varies, depending on the site and cause of the initial infection, the organs affected and the extent of any damage.

You'll usually be referred to hospital for diagnosis and treatment if you have possible early signs of sepsis. Severe sepsis and septic shock are medical emergencies.

Management of sepsis after admission to hospital usually involves three treatments and three tests, known as the "sepsis six". These should be initiated by the medical team within an hour of diagnosis.

Treatment involves:

  • giving antibiotics – if the sepsis is detected early enough, this may be a course of tablets you can finish taking at home
  • giving fluids intravenously
  • giving oxygen if levels are low

These treatments are described in more detail on this page.

Tests will include:

  • taking blood cultures – to identify the type of bacteria causing sepsis
  • taking a blood sample – to assess the severity of sepsis
  • monitoring your urine output – to assess severity and kidney function
Emergency treatment

You'll need emergency hospital treatment and may require admission to an intensive care unit (ICU) if:

  • the sepsis is severe
  • you develop septic shock – when your blood pressure drops to a dangerously low level

ICUs are able to support any affected body functions, such as breathing or blood circulation, while the medical staff focus on treating the infection.

Because of problems with vital organs, people with severe sepsis are likely to be very ill. Up to 4 in every 10 people with the condition will die.

Septic shock is even more serious, with an estimated 6 in every 10 cases proving fatal.

However, sepsis is treatable if it is identified and treated quickly, and in most cases leads to full recovery with no lasting problems.

Antibiotics

The main treatment for sepsis, severe sepsis or septic shock is antibiotics.

If you have severe sepsis and septic shock, antibiotics will be given directly into a vein (intravenously).

Ideally, antibiotic treatment should start within an hour of diagnosis to reduce the risk of serious complications or death.

Intravenous antibiotics are usually replaced by tablets after two to four days. You may have to take them for 7 to 10 days or longer, depending on the severity of your condition.

Types of antibiotics

There won't usually be time to wait until a specific type of infection has been identified, so broad-spectrum antibiotics are given first.

These are designed to work against a wide range of known infectious bacteria and usually cure most common infections.

Once a specific bacterium has been identified, a more focused antibiotic can be used.

Viral infections

If the sepsis is caused by a virus, antibiotics won't work. Antibiotics are usually given anyway because it would be too dangerous to delay treatment until tests confirm the specific cause.

With a viral infection, you'll need to wait until your immune system starts to tackle the infection, although antiviral medication may be given in some cases.

Intravenous fluids

If you have sepsis, your body needs increased amounts of fluid to prevent dehydration and kidney failure.

You'll usually be given fluids intravenously during the first 24 to 48 hours after admission if you have severe sepsis or septic shock.

It's important that the doctors know how much urine your kidneys are making when you have sepsis so they can spot signs of kidney failure.

If you're admitted with severe sepsis or septic shock, you'll usually have a catheter inserted into your bladder to monitor your urine output.

Oxygen

Your body's oxygen demand goes up if you have sepsis.

If you're admitted to hospital with sepsis and the level of oxygen in your blood is low, you'll usually be given oxygen. This is either given through a mask or tubes in your nostrils.

Treating the source of infection

If a source of the infection can be identified, such as an abscess or infected wound, this will also need to be treated.

For example, any pus may need to be drained away or, in more serious cases, surgery may be needed to remove the infected tissue and repair any damage.

Increasing blood pressure

Medications called vasopressors are used if you have low blood pressure caused by sepsis.

Vasopressors are normally given intravenously while you're in an ICU. Extra fluids may also be given intravenously to help increase blood pressure.

Other treatments

You may also require additional treatments, such as:

  • corticosteroids or insulin medication
  • a blood transfusion
  • mechanical ventilation – where a machine is used to help you breathe
  • dialysis – where a machine filters your blood to copy the function of your kidneys

These treatments are mostly used in ICUs.

Risks

Everybody is potentially at risk of developing sepsis from minor infections. However, some people are more vulnerable, including people who:

  • have a medical condition that weakens their immune system – such as HIV or leukaemia
  • are receiving medical treatment that weakens their immune system – such as chemotherapy or long-term steroids
  • are very young or very old
  • are pregnant
  • have a long-term health condition – such as diabetes
  • have just had surgery, or have wounds or injuries as a result of an accident
  • are on mechanical ventilation – where a machine is used to help you breathe
  • have drips or catheters attached to their skin
  • are genetically prone to infections

Sepsis is a particular risk for people already in hospital because of another serious illness.

Bacterial infections that can be caught in hospital, such as MRSA, tend to be more serious, as these bacteria have often developed a resistance to many commonly used antibiotics

Recovery
Recovering from sepsis

Some people make a full recovery fairly quickly. The amount of time it takes to fully recover from sepsis varies, depending on:

  • the severity of the sepsis
  • the person's overall health
  • how much time was spent in hospital
  • whether treatment was needed in an ICU

Some people experience long-term physical and/or psychological problems during their recovery period, such as:

  • feeling lethargic or excessively tired
  • muscle weakness
  • swollen limbs or joint pain
  • chest pain or breathlessness

These long-term problems are known as post-sepsis syndrome. Not everyone experiences these problems.