Successful treatment of invasive <i>Aspergillus</i> rhinosinusitis and orbital aspergillosis with oral isavuconazole in a patient with contraindications to conventional first- and second-line therapy

Abstract Objectives Acute invasive fungal rhinosinusitis represents a severe, life-threatening condition that necessitates prompt diagnosis and intervention. In this case report, we discuss the use of isavuconazole, a novel, broad-spectrum triazole antifungal, approved for use in Canada in 2019 (Government of Canada. Summary Basis of Decision – Cresemba – Health Canada. Summary Basis of Decision. 2019. Accessed 6 June 2024. https://hpr-rps.hres.ca/reg-content/summary-basis-decision-detailTwo.php?linkID=SBD00424#:~:text=Summary%20Basis%20of%20Decision%20(SBD)%20for%20Cresemba&amp;text=Summary%20Basis%20of%20Decision%20(SBD)%20documents%20provide%20information%20related%20to,original%20authorization%20of%20a%20product) that can be considered an alternative to voriconazole. Methods We present the case of a 78-year-old man with a unique case of invasive Aspergillus rhinosinusitis and orbital aspergillosis. He was admitted for urgent left maxillary antrostomy, left anterior and posterior ethmoidectomy, and left transorbital resection of lesion tissue with orbital decompression. His treatment course was complicated by a contraindication to voriconazole because of prolonged QTc interval and inability to tolerate IV amphotericin B. Key findings The patient was treated with a 14-week course of isavuconazole as an alternative to voriconazole. At 3 months, there was no clinical evidence for infection, and the patient was sent for a computed tomography (CT) of the head and sinus to assess for evidence of active infection or bone destruction, which showed significant improvement in paranasal sinus inflammation and soft tissue infiltration. At his 6-month follow-up, his CT head showed regression in inflammatory change, with no deterioration in his sinusitis, and no further antifungal treatment was required. Conclusions Given the novelty of isavuconazole, there has been limited experience with its use in the setting of rhinosinusitis and orbital invasive aspergillosis. This case highlights isavuconazole as a reasonable alternative to voriconazole and other triazoles in patients that are intolerant or have contraindications related to QTc prolongation.