To evaluate the clinicopathological and mycological manifestations of fungal rhinosinusitis occurring in the Tengku Ampuan Rahimah Hospital, in Klang, Malaysia, which has a tropical climate.

Records of patients treated from 2009 to 2016 were analysed retrospectively. Data from the records were indexed based on age, gender, clinical presentations, symptom duration, clinical signs and mycological growth.

Of 80 samples, 27 (33.75 per cent) had fungal growth. Sixteen patients were classified as having non-invasive fungal rhinosinusitis and 11 as having invasive fungal rhinosinusitis. The commonest clinical presentation was nasal polyposis in non-invasive fungal rhinosinusitis patients (p < 0.05) and ocular symptoms in invasive fungal rhinosinusitis patients (p < 0.05). The commonest organism was aspergillus sp. (p < 0.05) in non-invasive fungal rhinosinusitis and mucorales in invasive fungal rhinosinusitis.

There is an almost equal distribution of both invasive and non-invasive fungal rhinosinusitis, as seen in some Asian countries. Invasive fungal rhinosinusitis, while slightly uncommon when compared to non-invasive fungal rhinosinusitis, is potentially life threatening, and may require early and extensive surgical debridement. The clinical presentation of nasal polyposis was often associated with non-invasive fungal rhinosinusitis, whereas ocular symptoms were more likely to be associated with invasive fungal rhinosinusitis.

We report an extremely rare case of a fungus ball within a mucocele of the sphenoid sinus and infratemporal fossa.

A 62-year-old woman was referred for evaluation of a mass lesion in the left sphenoid sinus and infratemporal fossa. Endoscopic examination of the nasal cavity was unremarkable. Computed tomography showed a non-enhancing, expansile mass with calcifications in the sphenoid and infratemporal fossa; T2-weighted magnetic resonance imaging revealed marked hypointense signals within the sphenoid sinus mass, with an intermediate signal intensity. A presumptive diagnosis of a mucocele was made. During surgery, a profuse amount of yellow fluid was drained from the mucocele. Clay-like material was noted within the mucocele, corresponding to the hypointense magnetic resonance imaging signals; this was identified as aspergillus on histopathological examination. Radiological findings for a fungus ball within a mucocele can be similar to those for allergic fungal sinusitis, which shows mixed low and high attenuation on computed tomography and low-signal intensity on T2-weighted magnetic resonance imaging, within an expansile, cystic lesion.

Although an association between a fungus ball and a mucocele is rare in the paranasal sinuses, this disease entity should be considered in the differential diagnosis of expansile, cystic sinus lesions.