Allergic Aspergillus sinusitis (AAS) is a three decade old clinicopathologic entity in which mucoid impaction akin to that of allergic bronchopulmonary aspergillosis (ABPA) occurs in the paranasal sinuses. Features such as radiographic evidence of pansinusitis, passage of nasal plugs and recurrent nasal polyposis in patients with an atopic background is suggestive of AAS. Histopathlogic confirmation from the inspissated mucus is a sine qua non for the diagnosis. Heterogeneous densities on computed tomography of the paranasal sinuses are caused by the 'allergic mucin' in the sinuses. Many patients give a history of having undergone multiple surgical procedures for symptomatic relief. The current approach to treatment appears to include an initial surgical debridement followed by postoperative oral corticosteroids for long durations. Although both ABPA and AAS are classified as Aspergillus-related hypersensitivity respiratory disorders, their co-occurrence appears to be an infrequently recognised phenomenon. This could perhaps be attributed to the fact that these two diseases are often treated by two different specialties. A high index of suspicion is required to establish the diagnoses of ABPA and AAS. All patients with asthma and/or rhinosinusitis along with sensitisation to Aspergillus antigens are at an increased risk of developing ABPA and/or AAS. ABPA must be excluded in all patients with AAS and vice versa. Early diagnosis and initiation of appropriate therapy could plausibly alter the course of the disease processes and prevent the possible development of long term sequelae.
Keywords: Allergic Aspergillus sinusitis, Allergic bronchopulmonary aspergillosis, Allergic fungal sinusitis, Aspergillus, Asthma, Rhinosinusitis