NRA RETA: Evaluation Of The Performance Of The Nitrate Reductase And Resazurin Titre Assay For The Detection of Mycobacterium Tuberculosis Complex From Sputum In A High Tb and Hiv Setting

Sponsor

Epicentre (Other)

Overall Status

Completed

CT.gov ID

NCT01053598

Collaborator

Mbarara University of Science and Technology (Other), Medecins Sans Frontieres, Netherlands (Other)

600

Enrollment

Location

Duration (Months)

Patients Per Site Per Month

Study Details

Study Description

Brief Summary

The Principle objective of this study is To evaluate the performance of NRA, NRA-p and REMA-p for the detection of M. tuberculosis complex from sputum samples from adult pulmonary TB suspects in a high TB and HIV prevalence setting, using LJ and MGIT culture as gold standard.

The Secondary objectives are:

To measure the performance of each assay (NRA, NRA-p, REMA-p) in sputum smear-negative patients
To describe the results of the colorimetric methods in HIV-positive and HIV-negative patients
To assess the time to detection of both NRA/NRA-p, REMA-p methods.
To evaluate the feasibility of the NRA, NRA-p, REMA-p methods.
To determine the rate of contamination of the NRA, NRA-p and REMA-p assays.
To evaluate the proportion and the clinical relevance of NTM among TB suspects in a high TB and HIV prevalence setting.
To provide capacity building for TB diagnosis in Mbarara.

Condition or Disease	Intervention/Treatment	Phase
Tuberculosis HIV AIDS HIV Infections

Detailed Description

Tuberculosis (TB) remains a leading cause of death in developing countries and its burden has been exacerbated by the concurrent HIV epidemic. Despite the advances in medicine, TB diagnosis still remains a challenge, especially in developing countries where diagnosis relies mostly on the detection of Mycobacterium tuberculosis complex (MTBC) by smear microscopy and/or culture. Smear microscopy is rapid, simple and not expensive but it lacks sensitivity. Culture on solid medium, which is performed in some well equipped laboratories, is more sensitive than microscopy but takes up to 8 weeks to obtain the result.

Colorimetric methods have been used for the rapid detection of drug sensitivity in M. tuberculosis either from isolates or directly from sputum. These methods rely on the detection of live bacteria through either enzymatic activity (nitrate reduction) or their ability to reduce an oxidation-reduction indicator, either in solid or liquid medium. They are fast, simple, and offer a good potential that should be evaluated for the diagnosis of TB.

The objective of this study is to evaluate the performance of colorimetric assays for the detection of M. tuberculosis complex from sputum samples from adult pulmonary TB suspects in a high TB and HIV prevalence setting, using Löwenstein Jensen (LJ) and Mycobacterium growth indicator tube (MGIT) culture as gold standard. The colorimetric methods evaluated here will be the solid medium-based nitrate reductase assay as described (NRA) or with an additional step using para Nitrobenzoic (PNB) acid for differentiation of MTBC and NTM (NRA-p), and the modified resazurin microplate assay, also using PNB for differentiation of MTBC and NTM (REMA-p).

. If any of the colorimetric assays is found to be accurate, significantly faster than conventional culture methods, and easy to perform, then it could be implemented in a tuberculosis culture laboratory. By reducing the time to detection compared to conventional culture and the costs compared to recent commercial methods, these assays offer a good alternative to conventional methods and might help to improve TB diagnosis in developing countries.

Study Design

Study Type:

Observational

Anticipated Enrollment :

600 participants

Observational Model:

Cohort

Time Perspective:

Prospective

Official Title:

EVALUATION OF THE PERFORMANCE OF THE NITRATE REDUCTASE AND RESAZURIN TITRE ASSAY FOR THE DETECTION OF MYCOBACTERIUM TUBERCULOSIS COMPLEX FROM SPUTUM IN A HIGH TB AND HIV SETTING

Study Start Date :

Sep 1, 2011

Actual Primary Completion Date :

Sep 1, 2012

Actual Study Completion Date :

Dec 1, 2012

Outcome Measures

Primary Outcome Measures

To evaluate the performance of NRA, NRA-p and REMA-p for the detection of M. tuberculosis complex from sputum samples from adult pulmonary TB suspects in a high TB and HIV prevalence setting, using LJ and MGIT culture as gold standard [7 Month]

Secondary Outcome Measures

-To measure the performance of each assay (NRA, NRA-p, REMA-p) in sputum smear-negative patients -To describe the results of the colorimetric methods in HIV-positive and HIV-negative patients [7 Month]

Eligibility Criteria

Criteria

Ages Eligible for Study:

14 Years and Older

Sexes Eligible for Study:

All

Accepts Healthy Volunteers:

Inclusion Criteria:

Pulmonary TB suspects as defined by a cough for more than 2 weeks
Age 15 years and above
Written informed consent signed

Exclusion Criteria:

Producing pure blood sputum or clear saliva
Producing less than 1 mL of sputum
Receiving anti TB treatment (isoniazid, rifampicin, streptomycin, pyrazinamide, ethambutol) or quinolone for more than 1 week in the month before inclusion.