There are many complications of serious infections, both local and systemic. 1. local infections, such as diabetic patients, diabetic foot co-infection, may have poor limb movement, edema, redness and pain. 2. if systemic, often due to the local spread of bacteria with the blood flow to the whole body, causing systemic organ dysfunction, and can also cause systemic symptoms of toxicity In the case of systemic disease, it is often due to the local spread of bacteria with the blood flow to the whole body, causing systemic organ dysfunction, and can also cause systemic toxic symptoms, and finally failure. For example, infectious shock, respiratory failure, liver and kidney failure, bone marrow suppression, etc. are all complications of severe infections. Serious infections are very difficult to treat because they involve the function of various organs and the dysfunction of the whole body system.