Bacteremia: Bacteria are present in the bloodstream. Bacteremia can result from a serious infection or from something as harmless as vigorous toothbrushing. Most often, only a small number of bacteria are present, and they are removed by the body on its own. In such cases, most people have no symptoms. However, occasionally, bacteremia leads to infections, sepsis, or both.
Sepsis: Bacteremia or another infection triggers a serious bodywide response (sepsis), which typically includes fever, weakness, a rapid heart rate, a rapid breathing rate, and an increased number of white blood cells.
Septic shock: Sepsis that causes dangerously low blood pressure (shock) is septic shock. As a result, internal organs typically receive too little blood, causing them to malfunction. Septic shock is life threatening.
Last full review/revision September 2008 by Lowell S. Young, MD