U.S. Department of Veterans Affairs


Date of this Version


Document Type



Clinical Infectious Diseases 1999;29:475-88


PCR and other sequence-based microbial detection methods, once considered to be only research tools, are being used increasingly in the clinical microbiology laboratory. As this technology expands into the clinical arena, clinicians will need to learn its advantages and limitations so that sound judgments can be made. Astute clinicians know that results of blood culture reports, whether positive or negative, must be interpreted using an understanding of the test employed and an assessment of the clinical scenario. Similarly, infectious diseases practitioner will need to expand their understanding of PCR-based diagnostics so that these powerful tests are used appropriately.

It is our goal to make PCR-based diagnostics understandable to clinicians. We will point out the limitations of conventional diagnostic methods for infectious diseases, discuss the advantages and limitations of PCR-based methods, and mention some current and future applications of this technology. We will not discuss every current or pending application of PCR to diagnostic microbiology; the reader is referred to other publications for additional details [1-3]. We emphasize the principles behind PCR-based diagnosis, and acknowledge a research oriented bias in our viewpoint.

The limitations of existing diagnostic methods and the potential of PCR-based detection and identification methods are demonstrated by a case from Stanford University Medical Center.