title: Correlation between culture of Mycobacterium tuberculosis and IgG antibody to Mycobacterium tuberculosis antigen-5 in the cerebrospinal fluid of patients with tuberculous meningitis.
abstract: A retrospective study was made of the correlation between culture of Mycobacterium tuberculosis and detection of IgG antibody to M. tuberculosis antigen-5 in cerebrospinal fluid (CSF) by means of an enzyme linked immunosorbent assay (ELISA). Mycobacterium tuberculosis was cultured from the CSF in 14 of 70 patients with a clinical diagnosis of tuberculous meningitis (TBM). IgG antibody to M. tuberculosis antigen-5 was demonstrated in significant titres (80-640) in all 14 culture-positive patients. Thus, positive correlation was observed between culture of M. tuberculosis and detection of IgG antibody in the CSF. As a result of this observation, the CSF from 56 culture-negative patients with a clinical diagnosis TBM was specifically investigated for the detection of IgG antibody to M. tuberculosis antigen-5 and the findings were correlated with those of culture-positive patients. The assay was positive in 34 of 56 patients, the antibody titre ranging between 80 and 640. In the CSF of 70 patients with non-tuberculous neurological diseases, the assay was negative at a dilution of 1 in 80. Thus, detection of IgG antibody to M. tuberculosis antigen-5 by indirect ELISA carried 100% specificity and 60.7% sensitivity for a tuberculous aetiology in culture-negative patients with TBM. The results of this study suggest that indirect ELISA for IgG antibody to M. tuberculosis antigen-5 in CSF holds definite promise in diagnosis of TBM, particularly when repeated cultures of CSF are negative for M. tuberculosis.
authors: Department of Pathology, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Trivandrum, India.
authors: V V
authors: VV
authors: Radhakrishnan
authors: M
authors: M
authors: Annamma
authors: S
authors: S
authors: Shobha
mesh_terms: D000907:Antibodies, Bacterial / Q000134:cerebrospinal fluid*; D000942:Antigens, Bacterial / Q000134:cerebrospinal fluid; D003470:Culture Media; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D007074:Immunoglobulin G / Q000134:cerebrospinal fluid*; D009169:Mycobacterium tuberculosis / Q000276:immunology*; D012189:Retrospective Studies; D014373:Tuberculin / Q000134:cerebrospinal fluid*; D014390:Tuberculosis, Meningeal / Q000134:cerebrospinal fluid / Q000276:immunology*
chemical_list: D000907:Antibodies, Bacterial; D000942:Antigens, Bacterial; D003470:Culture Media; D007074:Immunoglobulin G; C016603:Mycobacterium tuberculosis antigen 5; D014373:Tuberculin