17 research outputs found
A Toolbox for Tuberculosis Diagnosis: An Indian Multicentric Study (2006-2008): Microbiological Results
BACKGROUND: The aim of this multicentric prospective study in India was to assess the value of several microbiological tools that contribute to the diagnosis of tuberculosis (TB) according to HIV status. METHODS: Standard microbiological tools on individual specimens were analyzed. RESULTS: Among the 807 patients with active TB, 131 were HIV-infected, 316 HIV-uninfected and 360 had HIV-unknown status. Among the 980 non-active TB subjects, 559 were at low risk and 421 were at high risk of M. tuberculosis (Mtb) exposure. Sensitivity of smear microscopy (SM) was significantly lower in HIV-infected (42.2%) than HIV-uninfected (75.9%) (p = 0.0001) and HIV-unknown pulmonary TB patients (61.4%) (p = 0.004). Specificity was 94.5% in non-TB patients and 100% in health care workers (HCW) and healthy family contacts. Automated liquid culture has significantly higher diagnostic performances than solid culture, measured by sensitivity (74.7% vs. 55.9%) (p = 0.0001) and shorter median time to detection (TTD) (12.0 vs. 34.0 days) (p = 0.0001). Specificity was 100% in HCW and cured-TB patients, but was lower in non-TB patients (89%) due to isolation of Mycobacteria other than tuberculosis (MOTT). TTD by both methods was related to AFB score. Contamination rate was low (1.4%). AccuProbe hybridization technique detected Mtb in almost all culture-positive specimens, but MOTT were found in 4.7% with a significantly higher frequency in HIV-infected (15%) than HIV-uninfected TB patients (0.5%) (p = 0.0007). Pre-test classification significantly increased the diagnostic value of all microbiological tests in pulmonary TB patients (p<0.0001) but to a lesser degree in extrapulmonary TB patients. CONCLUSIONS: Conventional microbiological tools led to results similar to those already described in India special features for HIV-infected TB patients included lower detection by SM and culture. New microbiological assays, such as the automated liquid culture system, showed increased accuracy and speed of detection
Comparative frequency of Mycobacteria other than Tuberculosis Mycobacteria (MOTTs) isolated in culture-positive specimens of pulmonary and extrapulmonary TB patients according to their HIV status.
<p>HIV: Human Immunodeficiency Virus; TB: tuberculosis; MOTTs: Mycobacteria other than Tuberculosis.</p>*<p>missing recorded identification; TB: tuberculosis.</p
Flow chart of patients recruited to the multicentric study stratified by patient subgroups.
<p>Flow chart of patients recruited to the multicentric study stratified by patient subgroups.</p
Comparative frequency of positive results of liquid versus solid culture in pulmonary and extrapulmonary active tuberculosis patients according to HIV status.
<p>TB: tuberculosis; HIV: Human Immunodeficiency Virus; CI: confidence interval. *:<i>p</i> value of Comparison. **missing recorded culture;</p
Frequency of smear microscopy positive results of patients with active-TB according to their disease localization and HIV-status.
<p>3 patients had no AFB records;</p>**<p>7 patients had no AFB records.</p
Time to Detection (TTD) of respiratory tract specimens cultured with the automated liquid culture BacT/ALERT MP (white bar) and with the Löwenstein-Jensen medium (grey bar) in relation to AFB scoring of TB patients.
<p>TTD in days: median (IQR).</p
Comparative Time to Detection (TTD) of culture-positive specimens on solid (LJ) medium (grey bar) or with automated liquid (BacT/alert) (white bars) medium in active pulmonary and extrapulmonary TB patients according to their HIV status.
<p>TTD in days: median (IQR).</p
Comparative contamination rate of liquid versus solid culture in pulmonary and extrapulmonary TB patients according to their HIV status.
<p>HIV: Human Immunodeficiency Virus; TB: tuberculosis.</p
Comparative frequency of positive results of liquid versus solid culture in the adult high-risk controls studied.
<p>NA: not available; TB: tuberculosis; HIV: Human Immunodeficiency Virus.</p>*<p>Cultures were positive with Mycobacteria other than Tuberculosis (MOTT).</p
Influence of the physicians’ clinical suspicion score of tuberculosis on the frequency of <i>Mycobacterium tuberculosis</i> culture -positive results in active pulmonary and extrapulmonary TB patients according to their HIV status.
<p>NA: not available; AFB: acid fast bacilli; TB: tuberculosis; HIV: Human Immunodeficiency Virus. *TB diagnosis by culture within the group considered. CSTB: clinical suspicion of TB.</p