Archive · 29 Dec 2025
AIIMS Study Highlights Limitations of Smear Microscopy for TB Detection
A recent study by AIIMS in Gorakhpur found that the common TB test, smear microscopy, misses many TB cases.
The study looked at over 4,000 samples and found that smear microscopy only detected TB in 4.3% of cases.
A better test called TrueNat found TB in 13.7% of the same samples.
The study suggests that India should use more of these better tests to catch TB earlier and help eliminate the disease.
Experts say that using both old and new tests together can help control TB better, especially in places with fewer resources.
Early detection of drug resistance is also important to start the right treatment quickly.
Smear microscopy, the most common TB diagnostic test in India, has low sensitivity and misses many TB cases, especially in early-stage disease and patients with co-morbid conditions.
AIIMS study analyzed 4,249 samples and found smear microscopy detected TB in only 4.3% of cases, while TrueNat detected it in 13.7% of cases.
TrueNat, a chip-based real-time PCR test made in India, can rapidly detect TB and identify rifampicin resistance, which was found in 5.6% of confirmed cases.
Experts recommend expanding rapid molecular testing under the National Tuberculosis Elimination Programme (NTEP) to improve early detection and treatment outcomes.
Combining conventional microscopy with molecular diagnostics can strengthen TB control efforts, especially in rural and underserved areas.
- Who
- All India Institute of Medical Sciences (AIIMS), Gorakhpur
- What
- A study highlighting the limitations of smear microscopy in detecting TB cases
- When
- The study was released on Sunday (specific date not mentioned)
- Where
- India, with a focus on high-burden and resource-limited areas
- Why
- To improve TB diagnosis and control efforts, especially in early-stage disease, extra-pulmonary TB, and patients with co-morbid conditions like HIV and diabetes
- Study Conducted By
- All India Institute of Medical Sciences (AIIMS), Gorakhpur
- Journal Published In
- International Journal of Mycobacteriology
- Samples Analyzed
- 4,249 pulmonary and extra-pulmonary samples
- Smear Microscopy Detection Rate
- 4.3%
- TrueNat Detection Rate
- 13.7%
- Rifampicin Resistance Found
- 5.6% of confirmed cases
- Recommended Diagnostic Tool
- TrueNat Mycobacterium TB/rifampicin (RIF) test
- Programme for Expansion
- National Tuberculosis Elimination Programme (NTEP)
