Criteria for the diagnosis of sinus mycetoma

Recent improvements in the treatment options for fungal disease of the sinuses make rapid distinction between the syndromes of invasive and noninvasive sinusitis necessary. On the basis of the extensive review of the literature detailed here, we developed case-finding criteria for the noninvasive syndrome of sinus mycetoma. Using these criteria, we identified 20 cases of sinus mycetoma in the medical literature and compared findings in these patients to those of five patients with mycetoma evaluated in our clinics. Like those in the literature, our patients appeared immunocompetent and were often first seen for evaluation of symptoms other than those usually associated with sinusitis. Two were first seen with a new-onset seizure disorder and one with nasal obstruction alone. Patients from both groups more commonly had mycetoma in their maxillary sinuses, and fungus failed to grow from the cheesy, grey-green, hyphae-rich material removed at the time of surgery. Clinical features in our five patients, which are not noted in published reports of sinus mycetoma, included frequent atopy, nasal polyps, calcification within the sinus on computed tomography, and an excellent response to surgical treatment. Serendipitously, one patient had both allergic fungal sinusitis and a mycetoma in the same sinus. On the basis of this experience, we have modified our case-finding criteria into proposed diagnostic criteria for sinus mycetoma. The elements of these criteria are designed to: (1) exclude patients with invasive fungal sinusitis and (2) differentiate sinus mycetoma from other forms of noninvasive fungal sinusitis on the basis of specific histopathologic findings. This study and the criteria presented reflect our view that sinus mycetoma represents a distinct but not necessarily isolated element in the spectrum of noninvasive fungal disease of the sinuses.