Appropriateness of antifungal prescribing in Oman

BACKGROUND: The inappropriate use of antimicrobials has substantially contributed to the development of antimicrobial drug resistance. Appropriate antibacterial prescribing has been emphasised, with minimal focus on appropriate prescribing of antifungals. Evaluation of antifungal use in the clinical setting is essential to prevent unnecessary drug exposure, development of resistance, adverse effects, and high hospitalisation costs. OBJECTIVE: The purpose of this study was to assess the appropriateness of antifungal prescribing among adult patients at the Sultan Qaboos University Hospital (SQUH) in Oman. METHODS: In this retrospective, observational study, the study population comprised adult patients treated with oral or intravenous antifungals between July 2018 and December 2019. The appropriateness of treatment was assessed using guidelines from the Infectious Diseases Society of America (IDSA) and the National Comprehensive Cancer Network (NCCN), as well as a set of literature-based criteria that were modified by SQUH infectious diseases team to suit local practices. These criteria included indication, dosage, and potential drug interactions. The primary outcome was the frequency of adherence to the treatment guidelines for fungal infections. Descriptive statistics were used for data analysis. RESULTS: A total of 400 prescriptions were collected, of which 158 (39.5%) were for empirical therapy, 135 (33.8%) for targeted therapy, 69 (17.3%) for prophylactic therapy, and 38 (9.5%) for pre-emptive therapy. The overall appropriateness was 74.8%. The indication, dosage, and potential for antifungal-drug interactions were considered appropriate in 391 (97.8%), 314 (78.5%), and 381 (95.3%) prescriptions, respectively. Anidulafungin was the most prescribed antifungal agent, with 210 prescriptions (52.5%), followed by fluconazole with 102 prescriptions (25.5%), and voriconazole with 48 prescriptions (12%). CONCLUSION: In comparison with publised literature, our study revealed appropriate antifungal drug prescribing practices. However, studies with larger sample size in various hospital settings are necessary to confirm our findings on a national scale, and to obtain better statistical inferences and generalisability.