Pathological subtypes and sampling strategies determine diagnostic sensitivity in cervical lymph node tuberculosis: a...

Area of Science:

• Medical Microbiology
• Infectious Diseases
• Pathology

Background:

• Cervical lymph node tuberculosis (TB) diagnosis relies on various etiological techniques.
• Pathological characteristics of lymph node lesions can influence diagnostic yield.
• Optimal sampling strategies are crucial for maximizing detection rates.

Purpose of the Study:

• To evaluate how pathological subtypes and specimen collection methods affect the positivity rates of five diagnostic techniques for cervical lymph node TB.
• To identify the most effective diagnostic approach based on pathological findings and sample types.

Main Methods:

• Retrospective analysis of 198 surgically confirmed cervical lymph node TB cases.
• Stratification of cases by pathological subtypes (necrosis types, inflammation) and collection methods (surgical resection, drainage).
• Testing specimens using acid-fast bacillus smear microscopy, Mycobacterium tuberculosis culture, quantitative PCR for TB DNA, simultaneous amplification and testing, and GeneXpert.

Main Results:

• GeneXpert demonstrated the highest sensitivity (90.36%), followed by TB DNA (74.24%).
• Pathological features like liquefactive necrosis significantly enhanced positivity rates for GeneXpert and TB DNA assays.
• Drainage specimens showed higher positivity for TB DNA and GeneXpert compared to surgical resection specimens.

Conclusions:

• Etiological positivity rates in cervical lymph node TB are linked to specific pathological features.
• Maximizing sampling of liquefactive necrosis and utilizing diverse sampling techniques (surgical resection, drainage, needle biopsy) improve diagnostic accuracy.
• GeneXpert assay, combined with optimized sampling, offers superior diagnostic performance.