A nomogram model in invasive pulmonary aspergillosis diagnosis based on a retrospective study

Abstract

Backgroud:With the easing of governmental COVID-19 restrictions, an upward trend was found for Aspergillus isolation in hospitalized patients . Objectives:Our research aims to analyze the clinical significance of Aspergillus positivity in respiratory tract samples and construct a diagnostic model in clinical practice. Methods: We retrospectively analyzed Aspergillus-positive patients in the three time periods before and after the relaxation of COVID-19 measures. Patients were admitted in into death or survival group to analyze independent risk factors for mortality. Based on the current standards, we divided patients into Invasive pulmonary aspergillosis( IPA) group and colonization group, in an attempt to identify the risk factors for IPA.The independent risk factors of death and IPA were determined through logistic regression analysis.A nomogram model was constructed to evaluate the predictive value of risk factors in IPA diagnosis.Mann–Whitney U test was used to compare the differences between the laboratory indicators of the IPA and the colonization. Resluts: There were 60% (125/208）patients with COVID-19 infection. We found that the overall in-hospital mortality rate was 33.6% (70/208). IPA (p<0.001), old age (p=0.011), mechanical ventilation requirement (p<0.001),and corticosteroids expose (p=0.002) were independent risk factors for mortality, while antifungal treatment had a protective effect (p<0.037).The proportion of IPA in death and survival group were 80% and 48%(p<0.001), respectively.The nomogram was established based on respiratory tract bronchial disease , recurring fever, the use of at least two types of antibiotics, and number of positive Aspergillus culture has significant diagnostic value for IPA(AUC:0.813,sensitivity0.823,specificity:0.714) .Moreover, there were statistical differences between the IPA and colonization group in serum GM level, BDG level, neutrophil absolute value ,blood glucose level , and blood urea nitrogen level(BUN). Conclusion:Due to the rapid progression and high mortality rate of IPA, Aspergillus positivity in respiratory tract samples should be cause for concern.In our study,we created a nomogram model in invasive pulmonary aspergillosis diagnosis. When patients with underlying respiratory diseases , recurring fever and use different types of antibiotics, it is best to monitor of laboratory indicators, such as cultures,GM and BDG tests .If there is a high clinical suspicion, we recommend starting empirical treatment with triazole drugs.