An investigation on non-invasive fungal sinusitis; Molecular identification of etiologic agents
Abstract
Background: Fungal sinusitis is increasing worldwide in the past two decades. It is divided into two types including invasive andnoninvasive. Noninvasive types contain allergic fungal sinusitis (AFS) and fungus ball. AFS is a hypersensitivity reaction to fungalallergens in the mucosa of the sinonasal tract in atopic individuals. The fungus ball is a different type of noninvasive fungal rhinosinusitiswhich is delineated as an accumulation of debris and fungal elements inside a paranasal sinus. Fungal sinusitis caused by variousfungi such as Aspergillus species, Penicillium, Mucor, Rhizopus, and phaeohyphomycetes. The aim of the present study is to identifyfungal species isolated from noninvasive fungal sinusitis by molecular methods. Materials and Methods: During 2015–2016, atotal of 100 suspected patients were examined for fungal sinusitis. Functional endoscopic sinus surgery was performed using theMesserklinger technique. Clinical samples were identified by phenotypic and molecular methods. Polymerase chain reaction (PCR)sequencing of ITS1?5.8S?ITS2 region and PCR?restriction fragment length polymorphism with MspI restriction enzyme was performedfor molecular identification of molds and yeasts, respectively. Results: Twenty?seven out of 100 suspected cases (27%) had fungalsinusitis. Nasal congestion (59%) and headache (19%) were the most common clinical signs among patients. Fifteen patients (55.5%)were male and 12 patients (44.5%) were female. Aspergillus flavus was the most prevalent fungal species (26%), followed by Penicilliumchrysogenum (18.5%) and Candida glabrata species complex (15%). Conclusion: Since clinical manifestations, computed tomographyscan, endoscopy, and histopathological findings are very nonspecific in AFS and fungus ball; therefore, molecular investigations arecompulsory for precise identification of etiologic agents and appropriate management of these fungal infections.
Key words: Fungal agents, molecular identification, noninvasive, sinusitis