EVALUATION OF THE USE OF RESUSCITATION FACTORS IN THE BACTEC MGIT 960 SYSTEM FOR DETECTION OF Mycobacterium tuberculosis IN PAUCIBACILLARY SAMPLES
Name: FILIPE AUGUSTO COIMBRA DE ARAÚJO
Publication date: 24/10/2024
Examining board:
Name |
Role |
|---|---|
| LUCILAINE FERRAZOLI | Examinador Externo |
| MOISES PALACI | Presidente |
| SARAH GONCALVES TAVARES | Examinador Interno |
Summary: The dormancy of Mycobacterium tuberculosis (Mtb) challenges laboratory diagnosis,
as dormant subpopulations are not easily detected by conventional methods. The
objective of this study was to evaluate the use of culture filtrate (CF) in the BACTEC
MGIT 960 system to improve the detection of Mtb in 245 paucibacillary clinical samples
from patients suspected of having tuberculosis (TB). The study compared samples
inoculated in MGIT medium with and without the addition of Mtb CF. The results
showed that the addition of CF increased the sensitivity of the test, particularly in
extrapulmonary samples, with sensitivity and specificity for MGIT+CF being 97.50%
and 97.86%, respectively. In comparison, the Xpert MTB/RIF Ultra presented a
sensitivity of 60.53% and a specificity of 93.97%, while the egg-based medium showed
40% sensitivity and 91% specificity. Furthermore, the use of CF increased the
frequency of contamination in liquid cultures and did not alter the time to positivity of
MGIT. These findings suggest that the use of CF may be a promising tool for enhancing
the accuracy of TB diagnosis in samples with low bacterial load.
