All 8 TB-HLH patients underwent necessary infectious disease screening, and all of them presented etiological evidence of TB infection. In 2 cases, the rapid mycobacteria cultures using blood samples showed positive acid-fast stain results. In 1 case, the acid-fast stain of a sputum smear (bronchoscopy) was positive, whereas in 3 cases, positive acid-fast stain sputum using the polymerase chain reaction technique was found (the sputum sample was obtained via bronchoscopy in 1 case). In 1 case, the ascites tested were positive, and in another case, the cerebrospinal fluid was positive, both using the acid-fast stain method. Five of the patients received a T.SPOT TB examination with blood samples, and the results were all 0. For the remaining 3 patients, inspection was not available when they were in the hospital. Moreover, to evaluate the possibility of HLH secondary to cancers, 3 patients underwent positron emission tomography/computed tomography examination, and no clear signs of malignant diseases were found.