Species-specific immunocytochemical localization of Mycobacterium tuberculosis complex in fine needle aspirates of tuberculous lymphadenitis using antibody to 38 kDa immunodominant protein antigen.

Abstract

OBJECTIVE:

To examine immunocytochemical localization of Mycobacterium tuberculosis (MTB) complex antigen in fine needle aspiration (FNA) smears of tuberculous lymphadenitis (TBLN) using species-specific monoclonal antibody MTSS to 38-kDa immnunodominant protein antigen as a diagnostic adjunct to conventional cytomorphology and its advantage over Ziehl-Neelsen (ZN) microscopy. Study Design FNA smears from 340 cases-174 TBLN; 34 negative controls from nontuberculous, positive controls of 13 known acid-fast bacilli (AFB)-positive sputum smears; 50 blind controls; and 69 other controls (smears from stock cultures of bacterial, atypical mycobacteria and fungal species) were subjected to ZN and immunocytochemical staining using MTSS by the streptavidin-biotin method.

RESULTS:

Immunocytochemical staining was positive in 59 of 61 (96.7%) archival and 110 of 113 (97.3%) fresh FNA smears; ZN positivity for AFB was observed in 27 of 61 (44.2%) archival and 48 of 113 (42.4%) fresh FNA smears of TBLN.

CONCLUSION:

The immunostaining using MTSS showed a definite advantage over conventional ZN staining for detection and specific diagnosis of TBLN in FNA smears with 0% false positive results. Immunostaining of cytosmears with species specific antibody to MTB would prove to be a good diagnostic adjunct to morphologic diagnosis.

• Authors: Madhu Mati Goel, Puja Budhwar
• Journal: Acta cytologica (Acta Cytol) 2008 Jul-Aug Vol. 52 Issue 4 Pg. 424-33 ISSN: 0001-5547 [Print] Switzerland
• PMID: 18702359 (Publication Type: Comparative Study, Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Ag38 antigen, Mycobacterium tuberculosis
• Antibodies, Monoclonal
• Antigens, Bacterial
• Lipoproteins

Topics

• Antibodies, Monoclonal
• Antigens, Bacterial (analysis, immunology)
• Biopsy, Fine-Needle
• False Positive Reactions
• Humans
• Immunohistochemistry
• Lipoproteins (analysis, immunology)
• Mycobacterium tuberculosis (immunology, isolation & purification)
• Predictive Value of Tests
• Sensitivity and Specificity
• Species Specificity
• Staining and Labeling (methods)
• Tuberculosis, Lymph Node (microbiology, pathology)