Role of Molecular Diagnostics in Ocular Microbiology
- PDF / 258,025 Bytes
- 9 Pages / 595.276 x 790.866 pts Page_size
- 5 Downloads / 239 Views
OCULAR INFECTIONS (BH JENG, SECTION EDITOR)
Role of Molecular Diagnostics in Ocular Microbiology Parisa Taravati • Deborah Lam • Russell N. Van Gelder
Published online: 28 September 2013 Springer Science + Business Media New York 2013
Abstract Although microbial culture remains the gold standard for diagnosis of many ocular infections, the technique is limited by low yield, inability to detect certain organisms, and potentially long delays for results. DNAbased molecular diagnostic techniques use detection of specific nucleic acid sequences as evidence for presence of suspected pathogens. The polymerase chain reaction (PCR) is a powerful molecular biology technique that allows for detection of fewer than 10 copies of pathogen genome. Recent technical advances in PCR have permitted quantitation of pathogen load using quantitative PCR and have permitted multiplexing of primer sets. Use of pan-bacterial and pan-fungal primers for ribosomal DNA sequences has allowed diagnosis of bacterial and fungal infections using molecular techniques. In this review, we highlight recent advances in the application of PCR to the diagnosis of anterior segment and posterior segment ocular infectious diseases.
P. Taravati D. Lam R. N. Van Gelder (&) Department of Ophthalmology, University of Washington School of Medicine, Campus Box 359608, 325 9th Avenue, Seattle, WA 98104, USA e-mail: [email protected] P. Taravati e-mail: [email protected] D. Lam e-mail: [email protected] R. N. Van Gelder Department of Pathology, University of Washington School of Medicine, Seattle, WA, USA R. N. Van Gelder Department of Biological Structure, University of Washington School of Medicine, Seattle, WA, USA
Keywords Ocular infection Uveitis Polymerase chain reaction Acanthamoeba Keratitis Retinitis Toxoplasmosis Glaucomatocyclitic crisis
Introduction Microbial culture has been the mainstay of diagnosis of infectious diseases since the first pure bacterial cultures were produced by Koch in the 1880s. However, culture techniques suffer from a number of limitations that reduce their utility. Culture techniques are relatively insensitive. Yields for clearly infectious processes such as postoperative endophthalmitis (70 % [1]) and corneal ulcer (*55–60 % [2, 3]) are relatively poor. Cultures can be very slow, taking up to 2 weeks for fastidious organisms such as Propionibacterium acnes. Culture for certain organisms such as Acanthamoeba require complicated conditions and suffer from low yield. Viruses are difficult to culture; diagnosis often depends on clinical presentation, cytopathologic changes, or serologic evidence of prior infection. The polymerase chain reaction (PCR) is a molecular biologic technique for detection and analysis of specific DNA sequences. In PCR (Fig. 1), two short DNA oligonucleotides complementary to the sequence in the organism of interest are used to amplify the intervening DNA using a thermostable DNA polymerase. The resulting DNA fragment may be analyzed by gel electrophoresis to document the presence of DNA from the
Data Loading...
