Evaluation of polymerase chain reaction-based ribosomal DNA sequencing technique for the diagnosis of mycotic keratitis

Am J Ophthalmol. 2007 Sep;144(3):396-403. doi: 10.1016/j.ajo.2007.05.017. Epub 2007 Jul 12.

Abstract

Purpose: To evaluate the polymerase chain reaction (PCR) and sequencing-based ribosomal deoxyribonucleic acid (rDNA) typing technique for rapid and sensitive diagnosis of fungal keratitis.

Design: Laboratory investigation.

Methods: The present study included culture-based methods along with PCR and ITS2/5.8S rDNA sequencing to evaluate fungal infections in 32 corneal scrapings from patients with suspected mycotic keratitis.

Results: Good correlation was found between the culture and PCR rDNA sequencing-based methods. We also identified fungal strains that were noncultivable in routine culture medium and fungal strains, which have been reported scarcely in previous reports from eastern Indian studies.

Conclusions: The PCR and rDNA sequencing-based approaches may be useful alternatives to culture-based techniques for the rapid and sensitive diagnosis of fungal keratitis. We found that clinically significant pathogenic fungal strains can be detected and differentiated by this method in a short period. This method therefore is useful for the early treatment of fungal infection.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Cornea / microbiology
  • Corneal Ulcer / diagnosis*
  • Corneal Ulcer / microbiology
  • DNA, Fungal / analysis
  • DNA, Ribosomal Spacer / genetics*
  • Eye Infections, Fungal / diagnosis*
  • Eye Infections, Fungal / microbiology
  • Female
  • Fungi / genetics
  • Fungi / isolation & purification*
  • Humans
  • Male
  • Middle Aged
  • Mycological Typing Techniques
  • Mycoses / diagnosis*
  • Mycoses / microbiology
  • Polymerase Chain Reaction / methods*
  • RNA, Ribosomal, 5.8S / genetics*
  • Sequence Analysis, DNA

Substances

  • DNA, Fungal
  • DNA, Ribosomal Spacer
  • RNA, Ribosomal, 5.8S