[Basic and clinical evaluation of rapid diagnosis of tuberculosis by detecting tuberculostearic acid]

Tuberculostearic acid (TSA) is known to be one of the characteristic lipid in the limited species of the order Actinomycetale, including Mycobacterium tuberculosis. We studied the significance of detecting TSA in the diagnosis of tuberculosis from clinical specimens collected from 791 patients with various respiratory diseases by using gas--chromatography/mass--spectrometry. By our method, the detectable limit of TSA was around 10(2)-10(3) bacilli of Mycobacterium tuberculosis, and our method is as sensitive as culture examination for tuberculosis. In sputa collected from patients with active pulmonary tuberculosis (n=169), TSA positively was around 90%, while less than 10% false positive ws also recognized. In pleural effusion (n=81) and bronchial washing (n=91) collected from patients with active tuberculosis, the positivity of TSA was around 70%. We could also detect TSA in about 30% of clinical specimens collected from patients suspected of tuberculosis. The diagnostic sensitivity of TSA for tuberculosis was similar to that of adenosine deaminase activity (ADA), while TSA was slightly superior to ADA in specificity. These findings indicate that detection of TSA from clinical specimens is useful to make rapid diagnosis of pulmonary tuberculosis.