Tuberculosis is diagnosed mainly by sputum examination and imaging. Sputum examination includes sputum culture, which is considered positive if the sputum is positive for Mycobacterium tuberculosis or if the sputum smear is positive for Mycobacterium antacidum. If there is a typical TB lesion on imaging, the diagnosis of active TB is confirmed. If only the sputum is positive and there are no imaging findings to support the diagnosis, the diagnosis can be confirmed as a person with latent Mycobacterium tuberculosis infection. Inactive TB can be diagnosed if the TB test is negative and imaging shows calcified lesions, striated lesions, hard nodular lesions, or purified cavities. Currently, there are three main categories of TB, namely inactive TB, active TB, and latent TB infection.