| Abstract
Introduction: In developing countries, which is an endemic region in terms of tuberculosis,
there is an urgent need for fast, accurate and inexpensive serological tests. The aim of this study
was to determine the diagnostic value of serum immunoglobulin G (IgG) antibody by ELISA to
detect Mycobacterium tuberculosis.
Method: This study was performed on patients with pulmonary tuberculosis in 2017-2020. After
selecting the 2 case (Pulmonary Tuberculosis and latent tuberculosis, each had 30 patients, total
60 patients) and control (n = 30) subjects according to inclusion criteria, their blood samples
were obtained and analyzed in the reference laboratory by standard kits for IgG against 16, 36
and 40 kDa antigens of Mycobacterium tuberculosis.
Results: The mean age of the subjects was 50.60 years old. The majority of participants were
46 (51.1%) women. There was no significant difference between the two groups regarding sex
and age. Serological examination of patients with pulmonary tuberculosis showed 25 positive
results and only 4 of the control group had a positive result. Sensitivity, specificity, positive
and negative predictive values of serology test were 83.3%, 86.67%, 86.20%, and 87.88%,
respectively.
Conclusion: Despite the acceptable sensitivity of the serologic IgG test, according to the
statement of World health organization (WHO), it did not possess an acceptable specificity.
It is recommended that a wider range of different antigens to be studied. Also, it is essential
to evaluate the diagnostic value of the other immunoglobulins in patient in different stages of
disease. |