Serodiagnosis of tuberculous lymphadenitis using a combination of antigens.

Abstract

BACKGROUND:

The diagnosis of extra-pulmonary tuberculosis (EPTB) by conventional methods such as culture and microscopy has low sensitivity and requires an invasive procedure. A simple rapid serological test would be of great value.

METHODS:

Six antigens (ESAT-6, Ag85A, TB10.4, Rv3881c, lipoarabinomannan (LAM) and Ara6-BSA) were tested in an ELISA to detect antigen specific IgG and IgM antibodies in sera from 54 culture and histology-confirmed tuberculous lymphadenitis (TBLN) patients, among whom four were HIV seropositive, sera from 25 smear positive pulmonary tuberculosis (PTB) patients, 15 culture and histology-negative lymphadenitis (non-TBLN) patients (n=15) and 22 healthy controls (HCs).

RESULTS:

The sensitivities of the antigens for the detection of IgG in sera of TBLN patients ranged from 4 to 30 %. Specificities ranged from 91 to 100 % with sera from HCs. Sensitivities of the antigens for detection of IgM ranged from 0 to 15 % and specificities ranged from 91 to 100 %. LAM was the most potent antigen followed by ESAT-6 and Rv3881c for detection of IgG. However, the sensitivity for antigen specific IgG antibody detection was improved when LAM was combined with ESAT-6 and Rv3881c.The sensitivity was 54 % and the specificity 91 %.

CONCLUSIONS:

The study suggests that the combined use of LAM, ESAT-6 and Rv3881c for the detection of IgG in sera of TBLN patients could be a supplement to microscopy of fine- needle aspirate (FNA) to diagnose EPTB.

• Authors: Demissew Beyene, Kees Lumc Franken, Lawrence Yamuah, Abraham Aseffa, Harald G Wiker, Arend Kolk, Howard Engers, Paul Klatser, Lisbet Sviland
• Journal: Journal of infection in developing countries (J Infect Dev Ctries) Vol. 4 Issue 2 Pg. 96-102 (Mar 08 2010) ISSN: 1972-2680 [Electronic] Italy
• PMID: 20212340 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Antigens, Bacterial
• Bacterial Proteins
• Biomarkers
• ESAT-6 protein, Mycobacterium tuberculosis
• Lipopolysaccharides
• lipoarabinomannan

Topics

• Adult
• Antigens, Bacterial (blood)
• Bacterial Proteins (blood)
• Biomarkers (blood)
• HIV Infections (complications)
• Humans
• Lipopolysaccharides (blood)
• Sensitivity and Specificity
• Serologic Tests (methods)
• Tuberculosis, Lymph Node (complications, diagnosis)