The incidence rate of tuberculosis (TB) is very high in China, and data from Centers for Disease Control in recent years have shown a growing number of patients with multidrug-resistant TB and refractory TB. Treatment for patients with severe TB infection has drawn widespread attention. Further, the diagnosis of fever of unknown origin (FUO), which is commonly caused by infectious diseases, autoimmune diseases, and malignant tumors, has become a problem that clinicians often face in large general hospitals. With a diverse range of clinical manifestations, TB is a common cause of FUO.