Tuberculosis skin test is also known as tuberculin test, or PPD test for short. If the test is double circled, it is usually considered to be a strong positive skin test, and it is recommended that the patient should be seen by an infectious disease hospital in a timely manner. If the patient has no obvious lesions on chest imaging, and the blood count is normal, and the sputum test is not positive for tuberculosis, the symptoms are usually considered mild and can be temporarily observed. If the patient has obvious TB lesions on chest imaging and positive sputum test for TB, the patient is considered to have active TB and needs to be treated with isolation and early standardized anti-tuberculosis treatment.