Tan Xue Ting1*, Stephanie Jane Ginsapu1, Salina Binti Mohamed Sukur1, Surianti Binti Shukor1, Salwa Mansur Ali1, Fairuz Binti Amran1
1. Bacteriology Unit, Infectious Diseases Research Centre, Institute for Medical Research, National Institute of Health, Ministry of Health Malaysia, Setia Alam, 40170 Selangor, Malaysia.
Corresponding author: Tan Xue Ting, Bacteriology Unit, Infectious Diseases Research Centre, Institute for Medical Research, National Institutes of Health, Ministry of Health Malaysia, Setia Alam, 40170 Selangor, Malaysia,
CITATION: Tan XT, Ginsapu SJ, Mohamed Sukur S, Shukor S, Mansur Ali S, Amran F. Minimum inhibitory concentration of voriconazole against filamentous fungi from clinical isolates: a comparative evaluation of Sensititre ® YeastOne and CLSI M38 method. International Medical Research Journal. 2021 Jun;7(1):29–40.
ABSTRACT
Voriconazole is a triazole antifungal used to treat fungal infections. In this study, the susceptibility pattern of voriconazole against filamentous fungi was determined using Sensititre® YeastOne and Clinical & Laboratory Standards Institute (CLSI) M38 broth microdilution methods. Cultures of various filamentous fungi, including Aspergillus niger, A. flavus, A. fumigatus, A. versicolor, A. sydowii, A. calidoustus, A. creber, A. ochraceopetaliformis, A. tamarii, Fusarium solani, F. longipes, F. falciferus, F. keratoplasticum, F. oxysporum, Talaromyces marneffei, Rhizopus oryzae, R. delemar, R. arrhizus, Mucor sp., Poitrasia circinans, Syncephalastrum racemosum, and Sporothrix schenckii were received from various government and private hospitals throughout Malaysia. The identities of the isolates were confirmed, followed by their susceptibility testing via Sensititre® YeastOne and CLSI M38 broth microdilution methods. Significant differences between the two methods were calculated using the Wilcoxon sign rank test. The comparative analysis indicated a similarity in the MIC values for each isolate, with the geometric mean of Aspergillus spp., Fusarium spp., and T. marneffei falling within the range of 0.02 μg/ml to 2.00 μg/ml, except for A. calidoustus, F. solani, and F. keratoplasticum. Similarly, the geometric mean MIC for S. schenckii was approximately 3.00 μg/ml, while the geometric mean MIC for the members of the Zygomycete class was ≥ 6.00 μg/ml. The general trend observed in the MIC obtained by Sensititre® YeastOne was ±1 two-fold different compared to that obtained by the CLSI method. Overall, there was more than 70% agreement between the two methods for determining voriconazole susceptibility, except for A. sydowii. However, significant differences between the two methods were observed when testing A. niger, A. flavus, A. fumigatus, A. versicolor, A. sydowii, F. solani, and S. schenckii. In conclusion, the Sensititre YeastOne method appears to be an alternative approach for voriconazole susceptibility testing for selected species of molds isolated in Malaysia.
KEYWORDS: Susceptibility, voriconazole, Sensititre, CLSI, mould
