title: Rapid and Specific Diagnosis of Extrapulmonary Tuberculosis by Immunostaining of Tissues and Aspirates With Anti-MPT64.
abstract: Extrapulmonary tuberculosis (EPTB) constitutes about 15% to 20% of all cases of tuberculosis (TB). The confirmation of EPTB has always been a challenge to laboratory personnel. We aim to evaluate the diagnostic potential of immunostaining with anti-MPT64 in various EPTB specimens.
  
  
  
  We studied a total of 51 TB cases and 38 non-TB control specimens comprising of fine-needle aspirates and formalin-fixed biopsies. These were investigated using a combination of the Ziehl-Neelsen method, the Lowenstein-Jensen culture, immunostaining with anti-MPT64 and anti-BCG, and nested-polymerase chain reaction (PCR) for IS6110. Results of all the tests were compared using nested-PCR as the gold standard.
  
  
  
  Diagnostic validation of immunostaining for anti-MPT64 was performed using nested-PCR as the gold standard. The overall sensitivity, specificity, and positive and negative predictive values for immunostaining with anti-MPT64 were 100%, 97%, 97%, and 100%, respectively.
  
  
  
  Immunostaining using anti-MPT64 is a rapid and sensitive method for establishing an early and specific diagnosis of Mycobacterium tuberculosis infection. The technique is simple to be incorporated into routine pathology laboratories.
authors.affiliation: *Department of Pathology, R.D. Gardi Medical College, Ujjain, India †Central Clinical Laboratory, Ujjain Charitable Trust Hospital and Research Centre, Ujjain, India ‡Department of Public Health Sciences, Division of Global Health, Karolinska Institutet, Stockholm, Sweden §Department of Pathology, Haukeland University Hospital ∥Department of Clinical Science, University of Bergen ¶Department of Global Public Health and Primary Care, Centre for International Health, University of Bergen #Department of Thoracic Medicine, Haukeland University Hospital, Bergen, Norway.
authors.forename: Manju R
authors.initials: MR
authors.lastname: Purohit
authors.forename: Lisbet
authors.initials: L
authors.lastname: Sviland
authors.forename: Harald
authors.initials: H
authors.lastname: Wiker
authors.forename: Tehmina
authors.initials: T
authors.lastname: Mustafa
mesh_terms: D000942:Antigens, Bacterial / Q000276:immunology*; D044963:Biopsy, Fine-Needle; D006801:Humans; D007150:Immunohistochemistry; D008198:Lymph Nodes / Q000382:microbiology / Q000473:pathology*; D009169:Mycobacterium tuberculosis / Q000502:physiology*; D010994:Pleura / Q000382:microbiology / Q000473:pathology*; D011237:Predictive Value of Tests; D012680:Sensitivity and Specificity; D014376:Tuberculosis / Q000175:diagnosis*
chemical_list: D000942:Antigens, Bacterial; C510537:MPT64 protein, Mycobacterium tuberculosis