[Determination of tuberculostearic acid for diagnosis of tuberculous meningitis with negative culture of tubercle bacillus].

Tuberculostearic acid, a structural component of Mycobacterium tuberculosis, was identified by gas chromatography in cerebrospinal fluid from 44 out of 59 patients with tuberculous meningitis. Tuberculostearic acid was found in the cerebrospinal fluid of 5 patients out of 112 with non-tuberculous meningitis or non-infectious disorders. The results showed the test had a sensitivity of 74.6% and a specificity of 95.9%. Detection of tuberculostearic acid in cerebrospinal fluid is a rapid, sensitive and specific test for tuberculous meningitis.