Primary tuberculosis is the clinical type of tuberculosis that develops as a result of initial infection with the tuberculosis bacterium. The vast majority of patients are children and adolescents, and their lesions are characterized by a primary syndrome, which is characterized by primary tuberculosis lesions, lymphangitis, and hilar lymph node tuberculosis. The primary lesions are usually in the lower upper or upper lower lobe, adjacent to the subpleural, and as the tuberculosis multiplies, localized exudative lesions often predominate, followed by invasion of the corresponding hilar or mediastinal lymph nodes along the lymphatics, resulting in the primary syndrome. Primary pulmonary tuberculosis rarely forms cavities, but the presence of hilar lymph node tuberculosis and lymphangitis can lead to pulmonary atelectasis, lymph node bronchial fistula, bronchial dissemination, and also lymphatic hematogenous dissemination, causing tuberculous meningitis, pleurisy, peritonitis, etc. Some patients with primary tuberculosis may have arthralgia, erythema nodosum, herpetic conjunctivitis, keratitis, etc.