How To Understand Blood Poisoning (Septicaemia)
What is septicaemia?
Septicaemia - often referred to as 'blood poisoning' or 'sepsis' - is a potentially life threatening infection that is caused when large amounts of invasive organisms get into the blood stream. This serious condition affects thousands of people every year all over the world.
Although septicaemia can be a fatal condition most people who are treated quickly enough will recover. This wasn't always the case. Up until Joseph Lister (1827-1912 ), introduced aseptic surgery, the death rate from septicaemia after operations was very high. In later times, the discovery of anti-biotics also helped to reduce the fatalities.
So what are the main causes of septicaemia and why does this condition develop?
The main causes of septicaemia
Within the blood there are millions of white blood cells of various kinds that successfully defend the body against invasion for most of the time. However, there could be occasions where the amount of infection causing organisms are just too numerous for the white blood cells to cope with. In these circumstances, septicaemia can develop.
Before we go onto look at the causes here are the definitions of the two terms used - sometimes interchangeably - 'septicaemia' and 'sepsis'. Septicaemia generally means a build up of bacteria or other pathogens in the blood stream itself. Normally with an infection in the body it is confined to one area where the invading organisms are killed by the white blood cells. However, if this infection gets out of control, it can enter the blood stream - septicaemia - and then potentially spread to other areas of the body - this is known as sepsis.
NHS UK gives a number of causes that can lead to the development of septicaemia and sepsis:
- Lung infections - in particular pneumonia
- Appendicitis - this can lead to septicaemia and sepsis if the appendix ruptures before surgery can take place.
- Peritonitis - this is a major inflammation of the lining of the digestive system and is itself a serious condition.
- Bone infections - for example osteomyelitis.
- Infections of the central nervous system - for example meningitis, encephalitis.
- Heart infections - for example endocarditis.
- After surgical operations.
- Urinary tract infections - usually when the kidneys are also infected.
In most cases of septicaemia the person usually has a medical condition present or another situation where their immune system is not working to full strength.
The organisms most likely to lead to septicaemia are:
- Pneumococcus - there are many types of this organism. Two of the main conditions they cause are pneumonia and meningitis as well as septicaemia.
- Klebsiella - these organisms are commonly found in the human digestive system where they do no harm. However, if they move into other areas they can be responsible for causing very serious - even fatal - infections such as wound infections, meningitis and pneumonia as well as septicaemia.
- Pseudomonas - people can be carriers of this bacteria without it causing any harm. However, it can lead to serious infections that are hard to treat because pseudomonas has become resistant to many anti-biotics. Infections that it may cause are septicaemia as well as infection in wounds, the urinary tract and bone.
- Escherichia Coli (E. coli) - commonly found in the digestive tract of human beings. This organism can cause serious infections apart from septicaemia. However, the most common infection caused by E. coli are urinary tract infections including cystitis. This organism can also cause inter-abdominal, intestinal infections and in young children (although rare) meningitis.
- Staphylococcus - normally a cause of skin infections if this bacteria gets inside the body it can cause dangerous medical conditions including septicaemia. Other conditions it can cause inside the body are - pneumonia, osteomyelitis, and endocarditis.
- Streptococcus - in addition to septicaemia this organism, when it reaches deep inside the body, can cause - pneumonia, meningitis, osteomyelitis and many other conditions.
Signs and symptoms
There are only a few signs and symptoms of septicaemia. Although this condition can develop at home, frequently it is while people are in hospital that septicaemia occurs. This is especially true if a person has recently had surgery or had some form of catheter (tube) inserted into an area of the body. Catheters in particular can harbour various organisms and then introduce them directly into the body so by-passing one of the body's strongest defence mechanisms - the skin.
Septicaemia and sepsis signs and symptoms usually develop rapidly and include:
- Heartbeat is very fast.
- High temperature - over 38C (100.4F)
- Breathing increases and becomes rapid.
- Nausea, abdominal pain and diarrhoea may occur in some people.
- Confusion is also a frequent result of septicaemia/sepsis.
When septicaemia and/or sepsis is present this can lead to septic shock. This is a very serious, potentially fatal, condition that arises because of the immune system's reactions to fighting off large numbers of invading pathogens. When the body fights infection, inflammation develops due to infection-fighting chemicals. In septic shock inflammation reactions are far too numerous for the body to cope and the inflammatory chemicals - along with substances released by the bacteria - flood into the blood stream causing more infection. In addition, these chemicals cause blood pressure to drop dangerously low - death is not uncommon. Basically a person needs to be put on life support machines and given huge doses of antibiotics to try to clear all the body systems of infection and inflammation.
Symptoms of severe sepsis or septic shock include:
- Low blood pressure.
- Confusion or disorientation.
- Nausea and vomiting.
- Cold, clammy and pale skin.
Thankfully septicaemia is still a rare occurrence and when caught early enough is treated successfully. The concern for the future is - will there be a rise in septicaemia cases due to the anti-biotic resistance of many bacteria?