title: Detection of mycobacterium tuberculosis by nested polymerase chain reaction in a case of subconjunctival tuberculosis.
abstract: OBJECTIVE
  To highlight the importance of nested polymerase chain reaction (PCR) in the detection of Mycobacterium tuberculosis in a case of subconjunctival tuberculosis.
  
  
  METHODS
  We report a case of a 60-year-old man with subconjunctival nodule in the right eye for duration of 6 weeks. Biopsy of the nodule showed a granuloma with extensive caseation necrosis. Ziehl Neelsen staining for acid-fast bacilli (AFB) was negative. However, because of a strong suspicion of Mycobacterium infection, PCR for M. tuberculosis genome was done, using the nested PCR technique.
  
  
  RESULTS
  Polymerase chain reaction for M. tuberculosis showed amplification of Mycobacterium tuberculosis genome with the nested PCR technique.
  
  
  CONCLUSIONS
  Our case indicates that PCR can be a valuable tool in the diagnosis of conjunctival tuberculosis from paraffin sections.
authors.affiliation: Medical & Vision Research Foundations, Sankara, Nethralaya Chennai, India. mrf@sankaranethralaya.org
authors.forename: Jyotirmay
authors.initials: J
authors.lastname: Biswas
authors.forename: S Krishna
authors.initials: SK
authors.lastname: Kumar
authors.forename: Pankaj
authors.initials: P
authors.lastname: Rupauliha
authors.forename: Somen
authors.initials: S
authors.lastname: Misra
authors.forename: Ira
authors.initials: I
authors.lastname: Bharadwaj
authors.forename: Lily
authors.initials: L
authors.lastname: Therese
mesh_terms: D003229:Conjunctival Diseases / Q000175:diagnosis / Q000382:microbiology*; D004269:DNA, Bacterial / Q000032:analysis*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009169:Mycobacterium tuberculosis / Q000235:genetics* / Q000302:isolation & purification; D016133:Polymerase Chain Reaction; D014392:Tuberculosis, Ocular / Q000175:diagnosis / Q000382:microbiology*
chemical_list: D004269:DNA, Bacterial