Abstract: Objective To monitor the clinically isolated fungi in Shandong Province from 2018 to 2021, and compare the difference in composition and antifungal drug sensitivity of isolated fungi between children and adults. Methods Based on the Shandong Province pediatric bacterial & fungal antimicrobial resistance surveillance system(SPARSS), clinical isolation fungal information from 47 comprehensive hospitals, 11 maternal and child health hospitals, and 1 childrens hospital in Shandong Province from 2018 to 2021 was collected, and WHONET V5.6 software was used to analyze the composition and drug sensitivity of fungi in different populations. Results A total of 15,348 strains of fungi were collected, of which 95.5% were isolated from adults and 4.5% from children. The predominant fungi isolated were Candida(78.4%)and Aspergillus(17.8%). Among the Candida isolates, C. albicans(41.8%), C. tropicalis(22.7%), C. glabrata(17.5%), and C. parapsilosis(11.0%)were the most common, while Aspergillus isolates were predominantly composed of A. fumigatus(53.7%), A. flavus(15.3%), and A. niger(7.2%). The top five fungi isolated from adults were C. albicans(32.1%), C. tropicalis(18.1%), C. glabrata(14.0%), A. fumigatus(9.8%)and C. parapsilosis(8.5%). For children, the top five isolated fungi were C. albicans(47.3%), C. tropicalis(11.2%), C. parapsilosis(10.6%), C. glabrata(6.8%), and A. fumigatus(4.4%). A total of 1,989 fungal isolates were obtained from sterile specimens, predominantly composed of Candida(90.2%)and Cryptococcus(4.3%). During the 4 years, no significant trend was observed in the fungal composition from adults. However, among the isolates from children, there was a decrease in the proportion of C. albicans and an increase in non-albicans Candida. Overall, the proportion of abdominal dropsy isolates identified as C. albicans decreased from 61.8% in 2018 to 46.2% in 2021. Most Candida species exhibited high sensitivity to amphotericin B, with wild-type rates exceeding 97%. Candida species varied significantly in their susceptibility to azoles, with the susceptibility rates of C. albicans and C. parapsilosis to fluconazole and voriconazole were 91.7%/84.7% and 91.6%/87.4%, respectively, while C. tropicalis were 67.8% and 40.6%. C. tropicalis showed a sustained decrease in susceptibility to azoles, with susceptibility rates to fluconazole and voriconazole decreased from 70.4%/46.4% in 2018 to 65.3%/35.2% in 2021. The resistance of some Candida species from children and adults to azoles was different. The resistance rates of C. tropicalis isolated from children to fluconazole and voriconazole were 40.6% and 32.8%, higher than 27.4% and 23.2% in adult isolates. The resistance/non-wild type rates of C. glabrata isolated from children to fluconazole and voriconazole were 16.2% and 25.7%, higher than 3.4% and 18.0% in adult isolates. Conclusion In Shandong Province, Candida and Aspergillus are the predominant fungi isolated. There are differences in the fungal species composition and drug sensitivity between adults and children. The declining trend of C. albicans in pediatric patients and the higher resistance of non-albicans Candida to azoles contribute to a more critical situation of antifungal resistance in pediatric fungi. Additionally, the annual decrease in susceptibility of C. tropicalis to fluconazole also warrants attention and corresponding measures.

Key words: Fungi, In vitro antifungal susceptibility test, Adult, Children, Azoles, Candida tropicalis