title: 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.
  
  
  CONCLUSIONS
  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.affiliation: Department of Pathology, King George's Medical University, Lucknow, Uttar Pradesh, India. madhukgmc@rediffmail.com
authors.forename: Madhu Mati
authors.initials: MM
authors.lastname: Goel
authors.forename: Puja
authors.initials: P
authors.lastname: Budhwar
mesh_terms: D000911:Antibodies, Monoclonal; D000942:Antigens, Bacterial / Q000032:analysis* / Q000276:immunology; D044963:Biopsy, Fine-Needle; D005189:False Positive Reactions; D006801:Humans; D007150:Immunohistochemistry; D008074:Lipoproteins / Q000032:analysis* / Q000276:immunology; D009169:Mycobacterium tuberculosis / Q000276:immunology / Q000302:isolation & purification*; D011237:Predictive Value of Tests; D012680:Sensitivity and Specificity; D013045:Species Specificity; D013194:Staining and Labeling / Q000379:methods*; D014388:Tuberculosis, Lymph Node / Q000382:microbiology* / Q000473:pathology
chemical_list: C075966:Ag38 antigen, Mycobacterium tuberculosis; D000911:Antibodies, Monoclonal; D000942:Antigens, Bacterial; D008074:Lipoproteins