GGN is an acronym that stands for Gross Glass Nodules with substantial, relatively high density, shadows in the lungs, which are mainly described by CT or MRI of both lungs. This pulmonary pathology is usually associated with inflammatory reactions in the lungs, including infections caused by specific pathogens, such as tuberculosis caused by Mycobacterium tuberculosis and bacterial pneumonia caused by bacteria such as Staphylococcus aureus and Klebsiella. If necessary, a PPD test, a culture of respiratory secretions for pathogens, or even a drug sensitivity test can be taken. The cause and condition of the disease can be clarified, and standardized treatment can be carried out formally.