Sepsis or septicaemia is a life-threatening illness that can occur when the whole body reacts to an infection. It leads to a serious overdrive of the body’s immune system and leads to a series of reactions that can lead to widespread inflammation and blood clotting.
Septicaemia or sepsis is defined as the presence of numerous bacteria in the blood, which are actively dividing. This causes the body to respond in such a manner that there may be organ dysfunction. There may be a collapse of blood circulation (shock), depression of the heart, increased metabolic rate and abnormalities or organ function and thus sepsis is not considered to be a mere infection alone.
Who is at risk of sepsis?
Vulnerable individuals who are at a greater risk of developing sepsis from a minor infection include:
- Those with a weakened immune system. This could be due to a diseases like AIDS, Diabetes etc. or due to medical treatment that suppresses the immunity like anti-cancer chemotherapy
- Very young children and infants and the elderly
- Those admitted in the hospital with a serious illness
- After a major surgery or a major accident
- After surgeries such as illegal abortion or instrumentation
- Alcohol abusers
- Those with extensive burns
How common is sepsis?
The Surviving Sepsis Campaign (SSC) estimates that the incidence of sepsis is 3 per 1,000 worldwide. It is estimated that there are over 30,000 cases of severe sepsis in the UK every year. There is a steady rise in the number of patients with sepsis. Worldwide there are over 18 million cases per year.
Because of its high mortality, sepsis is a leading cause of death. In the developing world, sepsis accounts for 60 to 70% of deaths per year. It kills over 6 million new-borns and children each year and there are over 100,000 cases of maternal sepsis. Each hour around 36 people die of sepsis and over 1.16 million people are affected annually in the US.
Symptoms of sepsis
Sepsis includes some of the following symptoms:
- High fever over 100.4F or 38C
- Chills and shivering
- Rapid breathing
- Rapid heart rate
- Confusion and disorientation
- Nausea and vomiting
What happens in sepsis?
Sepsis develops in three stages. These are outlined as follows:
- Uncomplicated sepsis caused by infections, such as dental abscesses, flu etc. and can be managed at home. Initial response with SIRS or systemic inflammation response syndrome.
- Severe sepsis occurs when the body’s response to infection has started to interfere with the function of vital organs. The organs affected are heart, kidneys, lungs or liver.
- Very severe cases may develop Septic shock. In these patients there is severe drop of blood pressure that prevents vital organs from receiving enough oxygenated blood
The stages are progressive and if untreated a case of uncomplicated sepsis may turn to septic shock and can eventually lead to multiple organ failure and death.
Complications of sepsis
Complications of sepsis include:
- Disturbed blood clotting
- Injury to the blood vessel walls or endothelial injury
- Excessive factors of infection in blood called tumour necrosis factor
- Excessive cell death or apoptosis leading to low counts of lymphocytes and endothelial cells
- Excessive activity of neutrophils
- Lack of blood sugar control
- Low levels of steroid hormones
How is sepsis treated?
Early uncomplicated sepsis is treated with antibiotics at home in many cases. Most people with uncomplicated sepsis make a full recovery.
Severe sepsis and septic shock, however, needs to be managed in the hospital. These are medical emergencies that need admission in the Intensive care unit. The body’s organs and blood pressure and breathing may need artificial support in the ICU. The risk of death in severe cases is as high as 30 to 50%.
Neonatal sepsis or sepsis in new-borns
Sepsis in new-borns refers to a serious bacterial infection like meningitis, pneumonia, gastroenteritis or kidney infection (pyelonephritis. It is difficult to clinically exclude sepsis in newborns less than 90 days old that have fever (defined as a temperature > 38°C (100.4°F). Neonatal sepsis is a grave entity leading to millions of infant deaths worldwide.
Outcome of sepsis
Prognosis or outcome of sepsis can be estimated with the MEDS score. Approximately 20–35% of patients with severe sepsis and 40–60% of patients with septic shock die within 30 days. Others die within the ensuing 6 months. Deaths that occur months later include poorly controlled infection, immunosuppression, complications of intensive care, failure of multiple organs, or the patient's underlying disease.
Reviewed by April Cashin-Garbutt, BA Hons (Cantab)