Molecular Diagnostics of Medically Important Infections

Northern Ireland Public Health Laboratory, Department of Bacteriology, Belfast City Hospital, Belfast, Northern Ireland, BT9 7AD, UK.
Current issues in molecular biology (Impact Factor: 5.75). 02/2007; 9(1):21-39.
Source: PubMed


Infectious diseases are common diseases all over the world. A recent World Health Organization report indicated that infectious diseases are now the world's biggest killer of children and young adults. Infectious diseases in non-industrialized countries caused 45% in all and 63% of death in early childhood. In developed countries, the emergence of new, rare or already-forgotten infectious diseases, such as HIV/AIDS, Lyme disease and tuberculosis, has stimulated public interest and inspired commitments to surveillance and control. Recently, it is reported that infectious diseases are responsible for more than 17 million deaths worldwide each year, most of which are associated with bacterial infections. Hence, the control of infectious diseases control is still an important task in the world. The ability to control such bacterial infections is largely dependent on the ability to detect these aetiological agents in the clinical microbiology laboratory. Diagnostic medical bacteriology consists of two main components namely identification and typing. Molecular biology has the potential to revolutionise the way in which diagnostic tests are delivered in order to optimise care of the infected patient, whether they occur in hospital or in the community. Since the discovery of PCR in the late 1980s, there has been an enormous amount of research performed which has enabled the introduction of molecular tests to several areas of routine clinical microbiology. Molecular biology techniques continue to evolve rapidly, so it has been problematic for many laboratories to decide upon which test to introduce before that technology becomes outdated. However the vast majority of diagnostic clinical bacteriology laboratories do not currently employ any form of molecular diagnostics but the use such technology is becoming more widespread in both specialized regional laboratories as well as in national reference laboratories. Presently molecular biology offers a wide repertoire of techniques and permutations of these analytical tools, hence this article wishes to explore the application of these in the diagnostic laboratory setting.

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    • "Given this issue, there is a growing interest in the development of new molecular approaches that can rapidly and categorically identify bacterial pathogens to the species level (Arancia et al., 2011). Molecular diagnostics of infectious diseases, especially DNA sequence-based methods, are the fastest growing field in clinical laboratory diagnosis and have the potential to revolutionize diagnostic tests and optimize the care of infected patients (Millar et al., 2007; Weile and Knabbe, 2009). The use of high-resolution melting analysis (HRMA) technology represents one of the most recent advances in the molecular diagnosis of clinically important bacteria (Lyon and Wittwer, 2009). "
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    • "The use of molecular approaches for clinical diagnosis has increased over the past 30 years since the development of PCR [1] resulting in a wide variety of diagnostic applications [2] [3] [4]. Alternative nucleic acid amplification (NAA) technologies, reviewed by Craw and colleagues [5] [6] [7], utilising isothermal conditions offer a range of potential advantages over PCR, including speed and simplicity, and lend themselves to near patient and point of care diagnostic testing [8] [9]. "
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    • "[4] Real-time polymerase chain reaction and microarrays are currently the most commonly employed molecular biology methods. [5] In addition, mass spectrometry (MS) has recently been established as a powerful method for direct microbial identification and biotyping. Especially matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) MS utilizing peptide/protein desorption and ionization from the surface of intact cells or spores provides fluent diagnostic tool on the basis of unique peptide/ protein mass spectra of the analyzed species. "
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