Application Of Loop-mediated Isothermal Amplification In The Detection Of Common Pathogens Of Pulmonary Infectious Diseases

Objective To develop a loop-mediated isothermal amplification(Lamp)technique for the detection of pathogens in patients with common pulmonary infections,detected bacteria contain twelve common pathogens and Mycobacterium tuberculosis,and to explore the value of Lamp in the detection of pathogenic bacteria in common lung infections in Tibet.Methods 108 cases of qualified sputum specimens of patients diagnosed with pulmonary infection from March 2017 to October 2018 in the People's Hospital of Tibet Autonomous Region were collected,all patients use Lamp detection.All suspected tuberculosis patients were tested for acid-fast staining,and collect general information,biochemical results,clinical conditions,etc,and Compare the results of Lamp and sputum culture and acid-fast staining.Combine the patient's hospitalization time,complication,age,etc.to analyze the lung infections in our hospital,to understand the effectiveness of the loop-mediated isothermal amplification technique in the pathogen examination of common lung infections in Tibet,and explore new ways of this method for clinical pathogen detection in Tibet.Results 1.A total of 57 pathogens were detected by LAMP in 95 Cases of pneumonia.The positive rate was 60.0%.Among them,44 were positive for any pathogen,of which 86.0%(49/57)were bacteria,they were mainly Gram-positive bacteria,and atypical pathogens accounted for 14.0%.A total of 13 beads of pathogenic bacteria were detected by sputum culture method,and the positive rate was 13.7%(13/95),they were mainly Gram-positive bacteria,undeveloped atypical pathogens,the results were roughly the same.In 13 patients with pneumonia complicated with pulmonary tuberculosis,7 cases were positive for LAMP,the positive rate was 53.8%,6beads were detected,3 cases were positive for acid-fast staining,the positive rate was 23.1%,and bacteria 1 beads were detected.2.There were 12 cases of LAMP pneumonia mixed infection,accounting for 12.6%(12/95).The two kinds of bacteria were mixed infection,and Sputum culture did not detect mixed infections.3.Each strain of LAMP reacts only with its corresponding DNA,without cross-reaction with each other,and has high specificity.4.LAMP can detect bacteria that are difficult to culture.Conclusion Loop-mediated isothermal amplification technology can detect pathogens of common lung infections and Mycobacteriu tuberculosis more conveniently,quickly and accurately than sputum culture and acid-fast staining,especially for bacteria that are difficult to culture.The LAMP results showed that Gram-positive bacteriawere the main pathogens of lung infection in our hospital,which laid the foundation for the development and research of LAMP in Tibet.