title: Diagnostic value of early secreted antigenic target-6 for the diagnosis of tuberculous meningitis patients.
abstract: BACKGROUND
  The early diagnosis of tuberculous meningitis (TBM) is very crucial, since delayed diagnosis can lead to various neurological manifestations. We have previously developed an in-house indirect enzyme-linked immunosorbent assay (ELISA) for TBM diagnosis using the Antigen 85 (Ag 85) complex. It has been suggested that the Ag 85 complex might give false-positive reactions for individuals vaccinated with Bacillus Calmette-Guérin (BCG).
  
  
  OBJECTIVE
  In the present study, we describe a prospective evaluation demonstrating that early secreted antigenic target- 6 (ESAT-6), which is absent in Mycobacterium bovis BCG strains, is in the cerebrospinal fluid (CSF) of TBM patients.
  
  
  METHODS
  We used an indirect ELISA to detect ESAT-6 antigens in the CSF of TBM patients using polyclonal antibodies against ESAT-6.
  
  
  RESULTS
  Using the indirect ELISA method, we demonstrated a sensitivity and specificity of 80% and 94%, respectively, for the diagnosis of TBM.
  
  
  CONCLUSIONS
  The detection of ESAT-6 in the CSF of TBM patients by indirect ELISA is a promising method and can be used to develop an immunodiagnostic assay with increased sensitivity and specificity.
authors: Biochemistry Research Laboratory, Central India Institute of Medical Sciences, Nagpur, India.
authors: R S
authors: RS
authors: Kashyap
authors: S S
authors: SS
authors: Ramteke
authors: S H
authors: SH
authors: Morey
authors: H J
authors: HJ
authors: Purohit
authors: G M
authors: GM
authors: Taori
authors: H F
authors: HF
authors: Daginawala
mesh_terms: D000328:Adult; D000368:Aged; D000942:Antigens, Bacterial / Q000134:cerebrospinal fluid*; D001426:Bacterial Proteins / Q000134:cerebrospinal fluid*; D002648:Child; D002675:Child, Preschool; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D014390:Tuberculosis, Meningeal / Q000175:diagnosis*; D055815:Young Adult
chemical_list: D000942:Antigens, Bacterial; D001426:Bacterial Proteins; C093276:ESAT-6 protein, Mycobacterium tuberculosis