Rapid detection of immunoglobulin G against Mycobacterium tuberculosis antigens by two commercial ELISA kits.
METHODS
Tunisia.


OBJECTIVE
To assess the clinical usefulness of the commercial Pathozyme-Myco G (Myco G) and Pathozyme TB complex plus (Patho) enzyme-linked immunosorbent assay (ELISA) kits for the rapid diagnosis of active tuberculosis (TB) and to distinguish between active TB and non-TB pulmonary diseases in Tunisian patients.


METHODS
Immunoglobulin G mediated humoral immune response against mycobacterial antigens (38 kDa and lipoarabinomannan, Myco G; 16 and 38 kDa, Patho) was evaluated in a group of active TB patients (128 smear-positive pulmonary and 33 extra-pulmonary samples) and in a control group (107 patients with non-tuberculous lung disease and two with leprosy). Active TB cases were confirmed by Mycobacterium tuberculosis culture from clinical samples.


RESULTS
The sensitivity of the Myco G test was 71% in active TB (pulmonary and extra-pulmonary), while the specificity was 100%. The Patho test showed a sensitivity of 43.5% with a specificity of 96.3%. A combination of both tests showed a sensitivity of 81% and a specificity of 96.3%.


CONCLUSIONS
Both ELISA tests were simple and easy to perform. Their combined use led to an increase in the diagnostic accuracy of active TB and its discrimination from non-TB pulmonary diseases. They could therefore be used as screening tools in poorly equipped laboratories in TB-endemic regions.
Ben Selma
W
W
Microbiology and Immunology Laboratory, UR02SP13, Centre Hospitalier Universitaire Farhat Hached, Sousse, Tunisia.
Harizi
H
H
Marzouk
M
M
Ben Kahla
I
I
Ben Lazreg
F
F
Ferjeni
A
A
Harrabi
I
I
Abdelghani
A
A
Ben Said
M
M
Boukadida
J
J
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000942:Antigens, Bacterial / Q000276:immunology*; D016022:Case-Control Studies; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods*; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D012680:Sensitivity and Specificity; D013997:Time Factors; D014376:Tuberculosis / Q000175:diagnosis* / Q000276:immunology; D014416:Tunisia; D055815:Young Adult
D000942:Antigens, Bacterial; D007074:Immunoglobulin G; C072681:Mycobacterium tuberculosis antigens