High neutrophils are common in clinical practice. In blood tests, neutrophils are a type of white blood cells and one of the most important indicators in routine blood tests. The common reasons for elevated neutrophils are as follows: 1. Generally, neutrophils are associated with infections and have a certain antibacterial effect, in bacterial infections, fungal infections, or mycoplasma and chlamydia infections, neutrophils will be elevated, and the normal ratio is generally 50%-70%, which is usually seen in bacterial infections, and it is one of the indicators for determining whether or not to add antibiotics in the clinic. 2. Neutrophil increase can also be seen in clinical diseases, such as infectious inflammation, rheumatoid arthritis, immune system diseases resulting in redness, swelling, heat, pain, etc., may cause neutrophil elevation.3, in the state of stress, such as car accidents, falls, injuries, and so on, can also be produced by the high neutrophil stress.4, in some hematological disorders, you can also see the neutrophil elevation phenomenon. The phenomenon of neutrophil increase can also be seen in some hematologic diseases. Therefore, simple neutrophil increase can not make a clear clinical diagnosis, need to assist other tests to further determine the causes of neutrophil elevation.