Principles and role of nucleic acid amplification and detection in diagnostic microbiology

In the recent decade, molecular tests have provided tools for highly sensitive and specific, culture-independent detection of infectious agents in clinical specimens. The rapid development of new methods and among these mainly the prototype method "polymerase chain reaction" (PCR) result in improved diagnostic procedures. Since its original description, a lot of modifications and advancements of PCR and alternative systems for in vitro amplification of nucleic acids have been developed to meet various requirements for improved detection of both DNA and RNA, quantification of the target molecules, and transfer from basic clinical research into a routine technique for clinical laboratory diagnosis. Since the purposes for which nucleic acid amplification methods should be used in the diagnosis of infectious diseases are often still uncertain, an evaluation and careful examination of the criteria for correct application of these techniques is needed. This review focuses on the recent developments in amplification procedures as well as on the use of these methods in the laboratory diagnosis of infectious diseases, The methodological limitations, future needs and perspectives are addressed.