Cme review: polymerase chain reaction diagnostics for posterior segment disease.

The polymerase chain reaction (PCR) is a powerful molecular biologic technique that permits detection and identification of infinitesimal quantities of DNA. It is well suited to the diagnosis of infectious posterior segment ocular inflammatory disease. In this review, the basic biochemistry of PCR, indications for its use, strengths and limitations to the technique, and examples of clinical application of PCR to posterior segment disease will be discussed. Emerging uses of PCR in linking pathogen to disease will also be outlined. After completion of this article, the reader will be able to describe the basic biochemistry and practical application of PCR in the diagnosis of posterior segment inflammatory disease, list the indications, advantages, and disadvantages of the technique, and outline the application of PCR diagnostics to individual differential diagnoses.