Re-emergence of fever after being discharged from the hospital with lobaric pneumonia may be caused by bacterial infection, recurrence of the disease or smoking. 1. Bacterial infection: When the body of a patient with lobaric pneumonia has a poor resistance to disease after discharge from the hospital, it is easy to develop secondary pathogenic bacterial infections, which may cause the lungs to be stimulated and cause the symptoms of fever again. 2. Recurrence: Patients with lobaric pneumonia may have recurrent episodes after being discharged from the hospital, and the symptoms of fever may appear again during the episodes. 3. Smoking: When patients with lobaric pneumonia smoke or abuse alcohol for a long time after discharge from the hospital, it may also trigger the disease to flare up and cause the patient to have fever again. At the same time, the reoccurrence of fever after discharge from the hospital should also be considered whether there is a combination of other diseases, such as rheumatic immune diseases, it is recommended to go to the hospital in a timely manner to take appropriate treatment.