IgG response to Mycobacterium tuberculosis non-polar lipids and sonicated extracts among tuberculous meningitis patients

Abstract

Introduction. The diagnosis of tuberculous meningitis (TBM) is a major global health concern due to its protean nature. There is a need to identify better biomarkers for the rapid and definitive diagnosis of TBM. Lipids have been poorly explored as diagnostic markers in TBM. Aim. Non-polar lipids (NPL) and mycobacterial sonicate extract (MTSE) antigens were assessed for diagnosis of Mycobacterium tuberculosis . Methodology. A total of 110 cerebrospinal fluid samples were categorized as confirmed, suspected and non-TBM cases according to clinical presentation and laboratory investigations, which were further analysed by NPL and MTSE ELISA. Results. The sensitivity and specificity of the NPL ELISA were 39.6 and 96 %, respectively, whereas the MTSE ELISA was 17 % sensitive and 92 % specific. The combination of the NPL and MTSE ELISA test was superior to these tests alone, with sensitivity and specificity of 43 and 88 %, respectively. Conclusion. This combination may be useful as an adjunct in the laboratory diagnosis of TBM. However, future studies in different settings among different populations, such as those with human immunodeficiency virus co-infection, are desirable to explore the full potential of biomarkers.