LABORATORY METHODS FOR THE DIAGNOSIS OF UPPER AND LOWER RESPIRATORY TRACT INFECTIONS IN CHILDREN

Аннотация

Sharp breath of the roads infections whole world along​ ​ children's illness and death​ ​ main from the reasons one to be global​ ​ on a scale respirator infections from 0 to 5 years old was​ ​ 2 million children close to death​ reason to be​ guess Approximately 80% of these respiratory infection cases are caused by viral pathogens such as influenza A and B, respiratory syncytial virus A and B, parainfluenza virus types 1-3, adenovirus, rhinovirus, human metapneumovirus, and others . Keywords: Electron microscopy, breath airways , red blood cells, influenza, respiratory virus, adenovirus, rhinovirus, human metapneumovirus . Research objective: Laboratory diagnosis of respiratory tract infections in children modern methods of identification Analytical review of modern scientific literature sources covering theissues. Materials andstyles. An analysis of 19literaturesources was conducted onthistopic. Introduction: Electron microscopy is one of the oldest direct detection techniques used in developed countries for both clinical virus diagnosis and the study of viral ultrastructure and pathogenesis . Historically, EM has played an important role in the identification of novel virus strains in several epidemic situations, such as the coronavirus associated with the severe acute respiratory syndrome (SARS) outbreak. However, despite several advantages, the use of EM is limited in respiratory virus diagnostics because it is expensive, laborious, time-consuming , and requires more time (approximately 3–16 h including sample preparation) and is often insensitive compared to other diagnostic methods. In addition, EM requires tight control of experimental conditions, high concentrations of viral particles (> 10 5L-1), and considerable technical skilland experiencefor accurate analysis. Culture method Virus detection by cytopathic effect and hemosorption in cell culture has been the “gold standard” for the diagnosis of respiratory viral pathogens for decades. Viruses such as adenovirus, influenza A/B, RSV, and human parainfluenza viruses are the most common respiratory viruses isolated and identified by cell culture . The traditional tube culture method is useful for growing a wide variety of viruses, including new or unknown viruses, but it takes days and often weeks to produce results. Over the years, modified cell culturemethods, such as the improved shell flask method of centrifugation, have reduced the cycle time from 5 to 10 days to 24 hours . Shell flask culture using combined cell lines 98,7:ROTCAFTCAPMI.SECNEICSLACIDEM ,5202 ,hcraM,5emuloV gro.srehsilbupcimedaca.www allows the simultaneous detection of multiple respiratory viruses and has similar sensitivity to conventional culture for parainfluenza 1-3 (87% vs. 83%) and influenza A/B (78% vs. 75%). %), and significantly higher sensitivity for RSV (73% vs. 42%). Despite these advantages, many clinically important viruses are difficult to grow in culture (e.g., rhinovirus and coronavirus) and can give variable results. In addition, multiple freezing and thawing of samples prior to testing can reduce viral titers, which can affect culture growth. Therefore, compared with molecular tests, traditional tube and shell vial culture methods are laborious, exhibit high false negative rates, and have longer turnaround times, making viral cultureless clinically relevant. Culture is also the gold standard for the detection of atypical (bacterial) respiratory pathogens, followed by identification and antimicrobial susceptibility testing using a variety of manual or automated methods . Bacterial culture can also often be insensitive, especially when the adequacy of the specimen is not determined by Gram stain or when specimens are collected after antibiotic exposure. Bacterial culture is also labor-intensive, requires considerable technical expertise, and if antibiotic susceptibility testing is performed, the turnaround time is typically 48–96 hours and may therefore be considered inadequate for optimalpatient careand management ofeffective antimicrobial therapy. Methodology: Express immunoenzyme test (EIT) Express immunoenzyme test (EIT) can deliver test results in less than 30 minutes and is typically performed in a POC setting, thus allowing the test results to be incorporated into a clinical decision-making algorithm. Four major EIT formats (latex agglutination, horizontal flow devices, lateral flow devices) Among the immunochromatographic methods (and optical immunoenzymes), lateral flow immunoenzyme (LOIF) is the most versatile and popular. RIAs are relatively inexpensive, easy to perform, and most of them have been waived in the United States under the Clinical Laboratory Improvement Act (CLIA) guidelines, making them This makes them invaluable in outpatient settings, primary care, emergency settings, and low-resource settings. Currently, commercially available RIAs are limited to the detection of influenza A virus, influenza B virus , and RSV. Many studies have shown