Changing Spectrum of Invasive Fungal Infections of Anterior Skull Base

ABSTRACT

Objective: The purpose of this study was to evaluate the change in clinical spectrum and outcomes of invasive fungal disease involving the anterior skull base region. Study Design: This study represents a retrospective review of the patients diagnosed with acute and chronic invasive fungal rhinosinusitis based on imaging, fungal staining and culture, biochemical analysis, and histopathology report. Assessment of anterior, central skull base including orbital involvement was done clinicoradiologically and/or intraoperative findings. Setting: A tertiary referral hospital. Results: There was a total of 79 patients, of which 67% had skull base mucormycosis, 33% had invasive aspergillosis. In the skull base mucormycosis group, there were 53 patients, with 33 males and 20 females. 88% of patients had a history of COVID-19 infection. 98% of patients had type 2 diabetes mellitus. The mean duration of symptoms was 36 days, and 68% of them presented 30 days after onset of symptom. Mortality was seen in 7 (14%) patients. The most common symptom of the presentation was facial swelling followed by facial numbness, vision loss and headache. The most common area of skull base involved was pterygopalatine fossa (88%), followed by infratemporal fossa (71%), anterior and posterior cribriform area (60% each). The most common vessel involved was the sphenopalatine artery (75%), and the neural structure involved was infraorbital nerve (64%) and maxillary division of trigeminal nerve (52%). 13 patients had an intracranial disease, with 2 having cerebritis and rest with parenchymal abscess including one patient with cerebellar abscess. All patients had radical debridement with antifungal treatment. In the invasive aspergillosis group, there were 26 patients with 12 males and 14 females with a mean age of 42 years. The mean duration of presentation after the onset of the symptom was 33 weeks. Only 26% of patients had diabetes mellitus (type 2), and one patient had COVID-associated aspergillosis who presented within 28 days after onset of symptom with intracranial extension. Tissue diagnosis for confirmation of aspergillosis was obtained in 62% of patients, while the use of galactomannan assay and clinicoradiological diagnosis was done in 38%. A similar trend of skull base involvement was seen.