What is in the TB Detection Kit?

The TRUPCR® One Step Nested Kit is a next-generation molecular diagnostic tool designed for the qualitative detection of TB (Mycobacterium tuberculosis complex, MTBC) and non-tuberculous mycobacteria (NTM) in a single, efficient workflow. It utilizes nested real-time PCR technology to improve the sensitivity of traditional molecular tests, allowing for robust detection even in samples with low bacterial load.

The kit targets:

• Two distinct conserved DNA regions of MTBC

• One genus-level marker for Mycobacterium spp. (to identify NTM)

• An endogenous internal control for quality assurance

Each assay includes all necessary reagents in a ready-to-use format and is CE-IVD certified for clinical use.

Role of MTBC and NTM in Disease

Tuberculosis (TB), caused by the Mycobacterium tuberculosis complex, continues to be a global health challenge. While pulmonary TB is the most common form, extrapulmonary TB affecting the spine, brain, kidneys, and lymph nodes is on the rise, especially in immunocompromised individuals. Mycobacterium tuberculosis grows slowly, dividing only every 18–24 hours, and requires high oxygen levels to thrive.

Non-tuberculous mycobacteria (NTM) are environmental organisms found in soil and water. Although previously considered non-pathogenic, NTMs like Mycobacterium avium complex, M. kansasii, and M. abscessus are now increasingly implicated in opportunistic infections, particularly in immunosuppressed patients or those with chronic lung disease.

The clinical distinction between MTBC and NTM is crucial, as the treatment regimens differ significantly. Misdiagnosis can lead to inappropriate antibiotic use and prolonged disease progression.

About the TRUPCR® One Step Nested Kit

The TRUPCR® One Step Nested Kit is tailored for high-sensitivity clinical workflows. Unlike conventional PCR assays, this kit leverages a single-tube nested PCR approach to reduce contamination risk and maximize yield. The dual-target system for MTBC improves specificity, while the genus-specific NTM probe ensures broad detection of over 170 NTM species.

Sample types validated for the kit include:

• Sputum

• Bronchial washings

• Cerebrospinal fluid (CSF)

• Urine

• Blood

• Endometrial and other tissue biopsies

The inclusion of an internal control in every reaction ensures that false negatives from PCR inhibition are minimized, maintaining confidence in every result.

Principle and Workflow

This assay works on a real-time fluorescence-based nested PCR principle. Here’s the simplified workflow:

1. DNA Extraction from clinical samples using validated methods

2. PCR Setup with TRUPCR® reagents in a single closed tube

3. First-round amplification with outer primers at high Tm

4. Nested amplification with inner primers at low Tm to boost sensitivity

5. Real-time detection of amplified DNA using fluorophore-labeled probes:

   • HEX/VIC channel for MTBC

   • FAM channel for NTM

   • TEX-RED for internal control

By measuring fluorescence only during the second amplification phase, the assay ensures that background signals are minimized. The threshold cycle (Ct value) directly reflects the presence or absence of TB or NTM DNA in the sample.

Clinical Application

This assay supports diagnostic workflows in:

• Clinical microbiology for early TB diagnosis

• Molecular diagnostics labs screening high-risk patients

• Reference labs conducting TB surveillance and epidemiology

• Hospitals handling complex or extrapulmonary TB presentations

Early detection of TB is essential to prevent spread and begin targeted therapy. This kit empowers labs to deliver results quickly, accurately, and across a variety of sample types. By distinguishing between TB-positive and NTM-positive samples, clinicians can avoid unnecessary treatments and apply the correct therapeutic regimen.

Moreover, the use of nested PCR within a single tube eliminates many of the contamination and workflow challenges traditionally associated with nested amplification techniques. The TRUPCR® TB solution provides a modern, validated answer to an age-old global health threat.