Bilateral proptosis—an unusual presentation of extensive allergic fungal sinusitis

Allergic fungal rhinosinusitis (AFRS) is counted as the most common form of fungal sinusitis. It is mainly due to the hypersensitivity reaction to fungal infection. Usually, the patients are atopic or immunocompetent. These patients are usually suffering from signs and symptoms of rhinosinusitis. The expanding mass in the disease leads to bony remodeling and the involvement of adjacent structures. When allergic mucin involves the orbit, many complications may occur. This includes diplopia, telecanthus, unilateral proptosis, malar flattening, epiphora, Asthenopia and even visual loss. The diagnosing of AFRS initially requires radiographic imaging, but to confirm the diagnosis, histopathological examination is needed. The treatment of AFRS should be combined with surgical and medical therapy. This case report demonstrates a unique and rare presentation of the non-invasive AFRS with bilateral proptosis which had dramatic improvement and resolution after we managed it with endoscopic sinus surgery, steroids and nasal saline irrigation.