A person with sepsis has a life-threatening infection of the bloodstream. Sepsis may occur in two ways. First, sepsis may be caused by needles, which mistakenly introduce bacteria into the bloodstream. Second, sepsis may be caused by bacteria that spread into the bloodstream from an infection in another organ. The most common sources of sepsis are bacterial infections of the skin, lungs, bone, and abdominal organs. Sepsis is more common in those who have a weak immune system.
Sepsis can lead to widespread inflammation and blood clotting. Inflammation may result in redness, heat, swelling, pain, and organ dysfunction or failure. Blood clotting during sepsis causes reduced blood flow to limbs and vital organs, and can lead to organ failure or gangrene (damage to tissues).
Sepsis can be frightening because it can lead to serious complications that affect the kidneys, lungs, brain, and hearing, and can even cause death. Sepsis can affect people of any age, but is more common in:
- infants under 3 months, whose immune systems haven't developed enough to fight off overwhelming infections
- the elderly
- people with chronic medical conditions and those on immunosuppressant medicines
- those whose immune systems are compromised from conditions such as HIV
Sepsis occurs when a serious infection causes the body's normal reaction to infection to go into overdrive. With sepsis, bacteria and the toxins they create cause changes in a person's body temperature, heart rate, and blood pressure, and can result in dysfunction of the body's organs.