Nucleic acid-based methods detect pathogen-specific DNA or RNA sequences were extracted from the agents. Sequences can be amplified in vitro partly, partly not.

Nukleinsäureebasierte (molecular) identification has become common practice in the clinical setting; the rapid identification allows the patient to undergo certain antimicrobial therapy and to avoid prolonged treatment with empirical, potentially ineffective drugs. Nucleic acid-based methods detect pathogen-specific DNA or RNA sequences were extracted from the agents. Sequences can be amplified in vitro partly, partly not. Nuckeinsäurebasierte methods are generally specific and highly sensitive and can be used for all categories of pathogens. The results can be very surprising. Since each test is typically specific to a single pathogen, the clinician needs to know the diagnostic possibilities and request the tests accordingly. For example, if a patient has symptoms suggestive of influenza, but influenza season is over, it’s better to have a general viral test (eg., Viral culture) to perform as a specific influenza test because another virus (eg. B- parainfluenza, adenovirus) may be the cause. Recent advances have led to the development of multiplex assays where a single nucleic acid-based test ? recognize two-causing microorganisms and can distinguish between them. Multiplex assays are less sensitive than Einzielziele, qualitative assays generally. Multiple samples are currently available for the detection of biological warfare agents. Nucleic acid-based methods are high, for a few, but but rising infections exist and quantitative methods (eg, HIV, cytomegalovirus, human T-cell leukemia virus.); these methods can be useful for the diagnosis and monitoring of therapeutic success. unreinforced test techniques that target nucleic acid sequences, but do not require amplification of these sequences are usually limited to cases in which the excitation already grown or in the sample in a high number appears (eg. as in caused by Group A Streptococcus pharyngitis, in genital Chlamydia trachomatis or Neisseria gonorrhoeae). Amplifying nucleic acid amplification using small amounts of DNA or RNA, to replicate this many times and can detect tiny traces of a pathogen in a sample, which can make a culture unnecessary. These techniques are especially useful for organisms that are difficult to detect culture or by other methods (eg. As viruses, obligate intracellular pathogens, fungi, mycobacteria, certain other bacteria) or which are only present in small numbers. These tests may include target amplification (eg., PCR, reverse transcriptase-PCR [RT-PCR] Verdrängung- stranded amplification, transcription amplification) signal amplification (eg. As branched DNA assays, Hybrid Capture) sample amplification ( z. B. ligase chain reaction, Cleavase invaders, cycling probes) Postamplifikationsanalyse (z. B. sequencing of the amplified product, microarray analysis and melting curve analysis, as it is performed in real-time PCR). Appropriate sampling and storage prior to arrival at the molecular diagnostic laboratory are critical. Since amplification methods are so sensitive, can easily occur false positive results due to track-like contamination. Despite the high sensitivity, it can sometimes lead to false negative results when a patient is symptomatic (eg. As with West Nile virus infection). False-negative results may be minimized by the following: prevention of swabs with wooden shafts or cotton swab (the swab that has been validated for the amplification assay must be used) Fast transport the sample freezing or cooling the sample when the transport is expected> 2 h in availing freezing is the typical retention method for nucleic acid amplification assays. However, the samples should be cooled better than frozen when labile viruses (eg. As varicella-zoster virus, influenza virus, HIV-2) is suspected or if the virus have to be performed (frozen samples can not for standard cultures used become).


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