Tuberculosis is caused by the invasion of Mycobacterium tuberculosis into the human body, mainly manifested by fever, mostly low fever in the afternoon, night sweats, weakness, loss of appetite, weight loss and other symptoms of systemic toxicity. Tuberculosis is divided into primary and secondary tuberculosis, and primary tuberculosis is more common in children. Primary tuberculosis is the tuberculosis caused by the first invasion of tubercle bacilli into the organism, and more than 90% occurs in the lungs. Primary tuberculosis includes primary syndrome and bronchial lymph node tuberculosis. Early symptoms vary in severity, and mild cases may be asymptomatic and detected on physical examination. Slightly severe cases have a slow onset, with loss of appetite, no weight gain or even loss, low fever, malaise, and night sweats. In severe cases, the onset is rapid, with sudden onset of high fever reaching 39-40°C, but the general condition is still good and not proportional to the fever, which may turn into low fever after 2-3 weeks with obvious symptoms of tuberculosis toxicity, which mostly occurs in infants and young children. When bronchial tuberculosis occurs, a series of symptoms of compression due to enlarged lymph nodes, such as whooping cough-like cough, wheezing and hoarseness, may also occur. In addition, some allergic symptoms, herpetic conjunctivitis, erythema nodosum, and allergic arthritis may be present. Mild to moderate enlargement of superficial lymph nodes may also be found. If you find the above symptoms, you need to consult a doctor promptly and treat with regular combination of anti-tuberculosis drugs as early as possible.