Retrospective analysis of 201 clinical isolates of Aspergillus fumigatus from a hospital in Nanjing: clinical characteristics of infected patients and azole resistance / 中华皮肤科杂志

ABSTRACT

Objective:To summarize clinical characteristics of patients with Aspergillus fumigatus infection in a hospital in Nanjing, to preliminarily assess azole resistance in clinical isolates of Aspergillus fumigatus, and to investigate risk factors for the emergence of azole-resistant Aspergillus fumigatus. Methods:Clinical isolates of Aspergillus fumigatus were collected from inpatients in Department of Laboratory, Nanjing Drum Tower Hospital from March 2017 to February 2021. Clinical data on these infected patients were analyzed, azole sensitivity testing and mutation analysis of the cyp51A gene and its promoter region were performed for these Aspergillus fumigatus isolates. Results:A total of 201 strains of Aspergillus fumigatus were collected, and mainly isolated from sputum specimens. Among the infected patients, there were 131 males and 70 females, and their age were 64.2 ± 15.8 years. The patients were mainly collected from department of respiratory medicine (79 cases), department of intensive medicine (34 cases), department of rheumatology (19 cases), etc. Among these patients, common underlying diseases included interstitial pneumonia (32 cases), malignant tumors (18 cases), pneumonia (13 cases), trauma (12 cases), systemic lupus erythematosus (8 cases), etc. Drug susceptibility testing showed that 6 (2.99%) strains of Aspergillus fumigatus were resistant to itraconazole and posaconazole, and 3 patients infected with azole-resistant Aspergillus fumigatus had used antifungal drugs before testing. Sequencing was performed on the cyp51A gene and its promoter region in the 6 strains of azole-resistant Aspergillus fumigatus, and showed TR34/L98H/S297T/F495I mutation in 5 strains and TR34/L98H mutation in 1 strain. Conclusion:Compared with previously published data about azole resistance in China during 2010 -2015, the resistance of Aspergillus fumigatus to azoles in Nanjing Drum Tower Hospital did not increase from 2017 to 2021, and the mechanism of azole resistance was mostly associated with TR34/L98H/S297T/F495I mutation in the cyp51A gene and its promoter region.