One of the reasons that sepsis can be so scary is that it can be caused by any infection of the body, even those that are not so apparent. Although sepsis is commonly caused by more severe infections such as a kidney infection or urinary tract infection, even an infected tooth can cause sepsis if left untreated.

Sepsis occurs when the bacteria from an existing infection causes systemic symptoms in the body. The immune system may be overwhelmed by the bacteria, causing more problems than solutions for patients. Sepsis in mild stages is relatively common. If left untreated or when the body does not respond to treatment, sepsis may become severe and turn to septic shock. In the event of septic shock, multi-organ failure and fatally low blood pressure may occur, leading to mortality in up to 40-50% of cases.