The routine blood results are not the only criterion for determining whether antibiotics should be applied, and in some cases, even if the routine blood is normal, it is necessary to apply antibiotics. The application of antibiotics needs to be analyzed in conjunction with the patient’s clinical symptoms, signs, laboratory tests (including routine blood, CRP, blood sedimentation, calcitoninogen, sputum culture, blood culture, urine culture, stool culture, etc.), imaging and other comprehensive factors. For example, mycoplasma pneumonia patients, clinical manifestations of fever, cough, cough sputum, imaging can be suggestive of pneumonia, laboratory tests are mostly suggestive of Mycoplasma pneumoniae IgM titer 1:320. because of Mycoplasma pneumoniae is an atypical pathogen, does not cause blood routine leukocytes, neutrophils increased (no bacterial infection manifestations). However, combining the patient’s symptoms, imaging, and other laboratory tests, the clinical diagnosis of pneumonia was established, and anti-infective treatment with quinolone or macrolide antibiotics was required. In conclusion, it is not possible to determine whether to apply antibiotics only based on the blood test results, but to follow the doctor’s instructions and standardize the treatment under the doctor’s comprehensive analysis.