What is sepsis?

Sepsis, also known as systemic inflammatory response syndrome (SIRS), is a serious medical condition caused by the body’s response to an infection. 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).

Who is at risk for sepsis?

Sepsis can strike anyone, but those at particular risk include:

  • People with weakened immune systems
  • Patients who are in the hospital
  • People with pre-existing infections or medical conditions
  • People with severe injuries, such as large burns or bullet wounds
  • People with a genetic tendency for sepsis
  • The very old or very young

What causes sepsis?

Bacterial infections are the most common cause of sepsis. Sepsis can also be caused by fungal, parasitic, or viral infections. The source of the infection can be any of a number of places throughout the body. Common sites and types of infection that can lead to sepsis include:

  • The abdomen: An inflammation of the appendix (appendicitis), bowel problems, infection of the abdominal cavity (peritonitis), and gallbladder or liver infections
  • The central nervous system: Inflammation or infections of the brain or the spinal cord
  • The lungs: Infections such as pneumonia
  • The skin: Bacteria can enter skin through wounds or skin inflammations, or through the openings made with intravenous (IV) catheters (tubes inserted into the body to administer or drain fluids). Conditions such as cellulitis (inflammation of the skin’s connective tissue) can cause sepsis.
  • The urinary tract (kidneys or bladder): Urinary tract infections are especially likely if the patient has a urinary catheter to drain urine

What are the symptoms of sepsis?

Because of the many sites on the body from which sepsis can originate, there is a wide variety of symptoms. The most prominent are:

  • Decreased urine output
  • Fast heart rate
  • Fever
  • Hypothermia (very low body temperature)
  • Shaking
  • Chills
  • Warm skin or a skin rash
  • Confusion or delirium
  • Hyperventilation (rapid breathing)

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