ICT; tuberculosis; diagnosis; infection; serology; rapid test
Abstract :
[en] The lCT tuberculosis is an in vitro immunodiagnostic test for the detection of
antibodies to Mycobacterium tuberculosis in serum or plasma. This test targets 5
recombinant M tuberculosis proteins, including the 38 and 85 KDa antigens. We
evaluated this test on 65 sera from patients with and without TB living in Liege.
Patients and methods: This test was performed on two groups : The TB group included
31 patients condidered to have an active tuberculosis : pulmonary (26 cases) or extrapulmonary (5 cases). All of them had at least one sample with positive culture and
received anti-tuberculous treatment. The identification of TB strains was performed
with Accuprobe M tuberculosis complexe (Gen-Probe). The second group (control
group) included 34 patients with the following characteristics: BCG negative nonexposed
healthy (19), BCG positive or exposed healthy (2), non-TB respiratory
disease (10), atypical TB (3). The identification of the atypical mycobacteria was
determined according to the biochemical characteristics or by molecular biology.
Results. The sensitivity is 38.7%, the specificity is 94%. The positive predictive value is 85.7%
and the negative predictive value is 62,7%. Two false lCT positive results were found
in the control group: both patients had a past infection with TB.
Conclusion: This test is very easy and rapid to perform, has a good specificity but
lacks sensitivity in low prevalence countries. A positive lCT allows same day
diagnosis of Mycobacterium tuberculosis infection.
Disciplines :
Immunology & infectious disease Laboratory medicine & medical technology
