The most commonly used test for infection indicators, which refer to abnormalities in tests caused by bacterial infections, is the blood count. When a person has a bacterial infection, the white blood cell count, neutrophil count, and neutrophil percentage of the routine blood tests are elevated to varying degrees, either simultaneously or partially, depending on the progression and severity of the disease. In addition, C-reactive protein and calcitoninogen tests can be performed, which have better sensitivity and specificity than routine blood tests. In addition, pathogenic tests such as bacterial smear and bacterial culture can be performed on the secretions of the infected lesion for further clarification. Usually, for patients with positive bacterial culture, further drug sensitivity tests can be performed, and the results of drug sensitivity tests can be used as a basis for antibiotic adjustment.