The term "blood poisoning" is really a misnomer as it is used to refer to the presence of bacteria in the blood, not a poisonous substance. The actual medical term for this is bacteremia. Although "blood poisoning" sounds rather ominous, the presence of bacteria in the blood is relatively common and is usually harmless. However, in some cases, it can lead to very serious complications.

How do bacteria enter the blood?

Bacteremia can occur due to regular activities and procedures. For example, bacteria that normally reside on your gums may become dislodged and enter your bloodstream when you brush your teeth or are getting a dental cleaning. During procedures, such as insertion of a catheter, bacteria that are normally present on the insertion site (e.g., bladder) may enter into the bloodstream. Bacteria can also enter your blood when you have certain infections, such as pneumonia or a urinary tract infection.

What happens when bacteria enter the blood?

Normally, a small amount of bacteria that briefly enter your bloodstream is not a problem, as your immune system can clear the bacteria on its own. Because of this, bacteremia usually does not cause any symptoms. However, if the bacteria remain in the blood for a long period of time and at high levels, this can lead to serious infections in different areas of the body. The bacteria can begin to accumulate in cells, tissues, bones, and joints, leading to a potentially life-threatening condition called sepsis.

Sepsis is a result of an exaggerated inflammation response that the immune system has to the bacteremia. This response affects the entire body, not just the site of infection. The excessive inflammation causes tiny blood clots to form in the blood vessels of the body. The blood clots prevent the required amount of oxygen from being delivered to the organs and they stop working.

What are the symptoms of bacteremia?

Bacteremia does not usually cause any symptoms when it occurs during regular activities such as brushing your teeth or getting a dental cleaning. However, signs of more severe bacteremia include a sudden high fever, chills, rapid heart rate, nausea, or vomiting. If you suspect that you have bacteremia, it is important to see a doctor right away to prevent it from progressing to sepsis.

What can be done to prevent bacteremia?

There are certain people who are at an increased risk of bacteremia. This includes people with a weakened immune system, people with certain medical conditions, people with heart valve abnormalities, and people with an artificial heart valve or joint or inserted catheter. To prevent bacteremia from occurring, antibiotics are normally given to at-risk individuals before dental procedures, surgery, and insertion of catheters.

Lisa Tourountzas