Sepsis is an inflammatory response to blood borne pathogenic infection. This inflammation can trigger a cascade of changes that can damage multiple organ systems, often times leading to death. Sepsis can be viewed as a three-stage syndrome, starting with SIRS (Systemic Inflammatory Response Syndrome), progressing through severe sepsis (sepsis complicated by organ failure, hypoperfusion, or hypotension), to septic shock (severe sepsis accompanied by hypotension that persists despite adequate intravenous fluids).
There are 751,000 severe sepsis cases in the US every year, out of which 383,000 (51.1%) require intensive care, and more than 215,000 (28.6%) are fatal. It is among the 10 leading causes of death. Between 1999 and 2005, 6.0% of all deaths in the United States were associated with sepsis. The number of people who die from sepsis every year is greater than breast cancer and lung cancer combined. The incidence of sepsis is increasing due to the aging population and the growing number of immunocompromised patients. Additionally, growing antibiotic resistance has compounded this problem. The total annual cost for the treatment of patients with severe sepsis in the United States has been estimated to be $17 billion in direct costs alone.