title: Rapid Mycobacterium tuberculosis DNA Detection on Fine Needle Aspirates from Extra Pulmonary Lymph Nodes.
abstract: OBJECTIVE
  To evaluate the diagnostic efficacy of two rapid methods i.e. Mycobacterium tuberculosis (MTB) Polymerase Chain Reaction (PCR) on Fine Needle Aspiration (FNA) samples by comparing with cytology of respective site sample.
  
  
  METHODS
  Cross-sectional comparative study.
  
  
  METHODS
  Department of Microbiology, Armed Forces Institute of Pathology (AFIP), Rawalpindi, Pakistan, from July 2010 through November 2013.
  
  
  METHODS
  A total of 105 extra pulmonary lymph nodes aspirates obtained through fine needle aspiration were processed. Cytology and PCR were done on each specimen. Cytology was taken as gold standard.
  
  
  RESULTS
  Out of the total 105 samples, 71 (67.6%) were positive for the MTB PCR while 34 (32.4%) showed negative status. According to FNA cytology (FNAC) results, 72 (68.6%) cases were positive for the disease while 33 (31.4%) were negative. Sensitivity of PCR was 90.3%, specificity 81.8%, positive predictive value (PPV) 91.5%, negative predictive value (NPV) 79.4%, with diagnostic accuracy of 87.6%. Area under the curve was 0.860 (p < 0.001).
  
  
  CONCLUSIONS
  PCR is a sensitive tool for detection of MTB on FNA samples from EPTB cases. The results are available within few hours which is helpful for the clinicians to initiate therapy.
authors.affiliation: Department of Microbiology, Armed Forces Institute of Pathology, Rawalpindi.
authors.forename: Aamer
authors.initials: A
authors.lastname: Ikram
authors.affiliation: Department of Microbiology, Baqai Medical University, Karachi.
authors.forename: Syed Azhar
authors.initials: SA
authors.lastname: Ahmed
authors.affiliation: Department of Microbiology, Armed Forces Institute of Pathology, Rawalpindi.
authors.forename: Farooq Ahmad
authors.initials: FA
authors.lastname: Khan
authors.affiliation: Department of Histopathology, Armed Forces Institute of Pathology, Rawalpindi.
authors.forename: Muhammad Tahir
authors.initials: MT
authors.lastname: Khadim
authors.affiliation: Department of Microbiology, Baqai Medical University, Karachi.
authors.forename: Luqman
authors.initials: L
authors.lastname: Satti
mesh_terms: D000328:Adult; D044963:Biopsy, Fine-Needle / Q000379:methods*; D003430:Cross-Sectional Studies; D003584:Cytological Techniques; D004269:DNA, Bacterial / Q000032:analysis* / Q000235:genetics*; D005260:Female; D006801:Humans; D008198:Lymph Nodes / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009169:Mycobacterium tuberculosis / Q000235:genetics* / Q000302:isolation & purification*; D010154:Pakistan; D016133:Polymerase Chain Reaction / Q000379:methods*; D011237:Predictive Value of Tests; D012680:Sensitivity and Specificity; D014388:Tuberculosis, Lymph Node / Q000175:diagnosis
chemical_list: D004269:DNA, Bacterial