The presence of flaky hyperdense shadows in the left lower lung is clinically considered to be pneumonia of the left lower lung. This kind of pneumonia is mainly caused by bacterial infection, which can be manifested as high fever, cough, coughing up pus sputum, and when the lung infection foci involve the pleura, there will also be chest pain, and some patients may also have blood in sputum, or nausea, vomiting, diarrhea symptoms. For left lower pneumonia, the main thing is to take sensitive antibacterial drugs to be anti-infective treatment, such as oral anti-inflammatory drugs, such as cephalosporins or penicillins to be anti-infective treatment, usually 5-7 days after the infection can be cured.