PCR for M. tuberculosis in tissue samples

Area of Science:

• Microbiology
• Pathology
• Molecular Diagnostics

Background:

• Granulomas in histopathology are not specific for tuberculosis diagnosis.
• Histopathological reporting for tissue samples takes 1-2 weeks.
• There is a need for rapid Mycobacterium tuberculosis detection in paucibacillary samples.

Purpose of the Study:

• To evaluate a PCR-assay for IS6110 for Mycobacterium tuberculosis detection in tissue samples.
• To compare PCR assay performance against histopathology as the gold standard.

Main Methods:

• A PCR-assay targeting the IS6110 gene was used.
• 104 diverse tissue samples were analyzed.
• Results were compared with histopathology findings.

Main Results:

• PCR demonstrated 74.1% sensitivity and 96.1% specificity.
• False positive rate was 2.88% (3/104) and false negative rate was 6.73% (7/104).
• Positive agreement between PCR and histopathology was 0.737, indicating substantial agreement.

Conclusions:

• PCR provides a rapid and sensitive method for early tuberculosis diagnosis in tissue samples.
• Timely diagnosis facilitates prompt anti-tubercular treatment initiation.
• Early intervention can prevent irreversible pathological changes.