Genus and species-specific IgG and IgM antibodies for pulmonary tuberculosis.
OBJECTIVE
To evaluate three different enzyme immunoassays for serological diagnosis of pulmonary tuberculosis and to compare their diagnostic accuracy in different combinations.


METHODS
A non-interventional comparative study.


METHODS
The study was carried out at the Department of Microbiology, Armed Forces Institute of Pathology, Rawalpindi between April and September 2001.


METHODS
Sera from patients suffering from pulmonary tuberculosis (n=94) with sputum positive for acid fast bacilli (AFB) and sera from control group of healthy individuals (n=90) with sputum negative for AFB were tested by Pathozyme-Myco G EIA, Pathozyme-TB Complex Plus EIA and Pathozyme Myco M EIA kits for the genus-specific IgG and IgM, and the species-specific IgG antibodies against antigens of Mycobacterium tuberculosis.


RESULTS
The detection of IgG against genus-specific antigens by Pathozyme-Myco G had a sensitivity of 46% and a specificity of 93%, of IgG against species-specific antigens by Pathozyme-TB Complex Plus had a sensitivity of 64% and specificity of 97% and of IgM against genus-specific antigens by Pathozyme Myco M had a sensitivity of 67% and specificity of 98%. When the results of these immunoassays were evaluated in combination, their sensitivity improved. Combination of genus-specific IgM and species-specific IgG yielded best results with a sensitivity of 87% and specificity of 93%.


CONCLUSIONS
The sensitivity of serological diagnosis of tuberculosis is low, but it can be increased by utilizing a combination of several antigens.
Butt
Tariq
T
Department of Microbiology, Armed Forces Institute of Pathology, Rawalpindi. tariqbutt24@yahoo.com
Malik
Hamid Saeed
HS
Abbassi
Shahid Ahmad
SA
Ahmad
Rifat Nadeem
RN
Mahmood
Abid
A
Karamat
Karamat A
KA
Anwar
Masood
M
D000907:Antibodies, Bacterial / Q000032:analysis*; D006801:Humans; D007124:Immunoenzyme Techniques / Q000379:methods; D007074:Immunoglobulin G / Q000276:immunology*; D007075:Immunoglobulin M / Q000276:immunology*; D011933:Reagent Kits, Diagnostic; D012680:Sensitivity and Specificity; D012698:Serologic Tests / Q000379:methods; D014397:Tuberculosis, Pulmonary / Q000175:diagnosis*
D000907:Antibodies, Bacterial; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D011933:Reagent Kits, Diagnostic