Syndromes of invasive fungal sinusitis

Invasive fungal sinusitis should be suspected in immunocompromised or diabetic patients who present with acute sinusitis, inflammation of nasal septal mucosa, unexplained fever or cough, or the orbital apex syndrome. Histopathological studies are required to differentiate among these syndromes. Acute (fulminant) invasive fungal sinusitis has been called mucormycosis, zygomycosis and fulminant invasive sinusitis. Fever, cough, crusting of nasal mucosa, epistaxis, and headache are the most common presenting symptoms. Histopathological studies show hyphal invasion of blood vessels, vasculitis with thrombosis, and tissue infarction. Reports of granulomatous invasive fungal sinusitis come primarily from Sudan, but also from India, Pakistan, and the United States. Patients usually present with proptosis, appear to be immunocompetent and are infected almost exclusively with A. flavus. Chronic invasive fungal sinusitis can be distinguished from the two other forms of invasive fungal sinusitis by its chronic course, dense accumulation of hyphae resembling a mycetoma, and association with the orbital apex syndrome, diabetes mellitus, and corticosteroid treatment. Biopsy and orbital exploration show vascular invasion by fungal elements and only a sparse chronic inflammatory infiltrate.