RESUMO
Objective: Nucleic acid testing can accurately and rapidly identify the presence of pathogenic bacteria. In this study, we analyzed respiratory pathogenic bacteria nucleic acids by LAMP (Loop-mediated isothermal amplification) to clarify the clinical application in patients with bacterial pulmonary infections. Methods: Clinical data and specimens were collected from 99 patients with bacterial pulmonary infections from June 2021 to April 2023. We compared the differences between nucleic acid detection of LAMP and sputum culture. The correlation between inflammation manifestations of pulmonary imaging and the nucleic acid detection of LAMP was compared and analyzed. And the relationship between LAMP and blood inflammatory markers were analyzed. Results: The positive rate of LAMP using sputum specimens was significantly higher than that of sputum culture (P < 0.05). Pathogenic bacteria in sputum samples are more likely to be detected by LAMP in patients with inflammatory on lung imaging examination. The coincidence rate of elevated PCT and CRP expression with positive LAMP results were 83.87 % and 88.71 %, respectively. Moreover, PCT, CRP and WBC were significantly higher in LAMP positive group than those in negative group (P < 0.05). Conclusion: Nucleic acid testing of sputum specimens for pathogenic bacteria by LAMP on the basis of imaging examination can provide a rapid and accurate experimental basis for clinical diagnosis of bacterial pulmonary infections.
RESUMO
BACKGROUND: Pulmonary fibrosis (PF) is a respiratory disease with end-stage pathological changes of interstitial lung disease that severely affects the survival of patients. Among the many biomarkers that have been identified, serum Krebs von den Lungen-6 (KL-6) is by far the most frequent marker for detecting pulmonary fibrosis. METHODS: We searched Medline (Pubmed), Embase, Web of science, and Cochrane databases for articles published between inception and August 2022 in order to explore the association between KL-6 and pulmonary fibrosis. Characteristics of patients and studies included in the articles were extracted by two independent investigators according to the inclusion and exclusion criteria. We reflected the accuracy of KL-6 in distinguishing between PF and non-PF by calculating sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and area under the curve by SROC curves. The presence of heterogeneity was reflected by I2 in the forest plot, and then the source of heterogeneity was investigated by meta-regression. RESULTS: We searched for 939 research papers, of which 16 met the inclusion criteria. Meta-analysis showed a sensitivity of 0.87 (95 % CI: 0.78-0.92), specificity of 0.91 (95 % CI: 0.86-0.95), positive likelihood ratio of 10.2 (95 % CI: 6.1, 17.0) and negative likelihood ratio of 0.14 (95 % CI: 0.08, 0.25) for KL-6 in diagnosing pulmonary fibrosis. The area under the receiver operating characteristic curve was 0.95 (95 % CI: 0.93-0.97). The results showed significant heterogeneity in both sensitivity and specificity (I2 = 94.55 and 91.52, respectively). Meta-regression analysis identified race as the cause of sensitivity heterogeneity and assay methodology as the cause of specificity heterogeneity. CONCLUSIONS: The analysis of this study suggests that serum KL-6 is a better tool for the diagnosis of pulmonary fibrosis when factors such as disease cause and control group category are not specifically considered.