Physiology of Sepsis

From a local infection to a body-wide injury

A local infection, such as pneumonia or a severe skin infection, overcomes the body’s local defense mechanisms. Invading micro-organisms and the toxins they produce induce a powerful body-wide immune response.


This immune response to infection can be so intense that the body can lose control of it. The ‘dysregulated’ response can result in injury to tissues and organs, and is known as sepsis.

Septic shock and multi-organ failure

Cardio-circulatory failure can develop, leading to a sudden drop in blood pressure. This is called septic shock. Several organs then stop functioning sequentially or simultaneously. This multi-organ failure often leads to death.