The Role of Nucleic Acid Amplification and Detection in the Clinical Microbiology Laboratory

Abstract

Clinical microbiology is in the midst of a new era. Methodology that is based on nucleic acid detection has slowly appeared in the diagnostic laboratory, and is revolutionizing our ability to assist physicians in the diagnosis and management of patients suffering from infectious diseases. Much like the introduction of immunoassays built around hybridoma technology in the 1980s, considerable doubt and promise exist hand in hand in the 1990s. Conventional testing that is technically straight forward, informative, and timely will always be a part of clinical microbiology; however, considerable room for improvement exists with organisms/diseases for which laboratory methods are limited. Nucleic acid methodology will have its greatest and long-awaited impact in this arena.

Characterisation of bacteria in ascites—reporting the potential of culture-independent, molecular analysis

“…The reporting of false-negative results, where no causative agent(s) are observed using traditional culture-based diagnostic microbiological analysis of samples, have been shown to occur in many infective scenarios [18]. In contrast to culture-based methodologies, the rapid and accurate identification of bacteria in clinical samples using molecular, culture-independent approaches has led to the rapid proliferation of the use of such strategies [19,20]. Their particular strength is in their ability to detect bacterial species, regardless of whether these species can be grown readily in vitro.…”

Comparison of 16S rDNA-based PCR and checkerboard DNA–DNA hybridisation for detection of selected endodontic pathogens

“…The latter factor is particularly advantageous in the study of strictly anaerobic infections, where cell death can occur during sampling and transportation. For these reasons, molecular technology has been used widely to survey clinical specimens directly for the occurrence of pathogenic micro-organisms [4,5].…”

Polymerase Chain Reaction and Advances in Infectious Disease Diagnosis

“…Streptococcal pharyngitis: In developed countries PCR diagnosis of Gp A haemolytic streptococci by PCR (Gp A Streptococcus direct test or GASD) is gaining importance since its definitive exclusion could curtail empirical treatment of pharyngitis, curtail use of beta lactam antibiotics, and reduce overall costs of therapy [12]. , Atypical pneumonia: A multiplex PCR based strategy wherein rapid diagnosis of infections caused by Chlymydia pneumoniae, Mycoplasma pneumonia and legionellae could help reshape the management of atypical pneumonias [14].…”

“…They cause not only a diagnostic dilemma but also the detection of their nucleic acid by amplification procedures may not be of clinical relevance. Quantitative assays for their presence are important and have been developed [14].…”