Allergic fungal sinusitis presenting as optic neuritis: A diagnostic dilemma

Abstract

Aim: To familiarize ophthalmologists with the rare but potentially vision-threatening complication of optic neuritis from allergic fungal sinusitis. This is a case report of a healthy young female who presented with rapidly deteriorating vision and clinical features of acute optic neuritis of the left eye. Computerized tomography of the brain and orbits revealed an invasive bilateral sphenoid sinus mass with encasement of the left optic nerve, bone erosion, and intracranial extension. Ear, nose, and throat examination revealed nasal polyposis with sinusitis. Endoscopic biopsy revealed extensive allergic fungal debris filling sinuses and eroding the medial end of the optic canal on left side suggestive of allergic fungal sinusitis. An emergency functional endoscopic sinus surgery and optic nerve decompression followed by systemic steroid therapy restored her vision. The culture of the nasal biopsy grew Aspergillus fumigatus.

Keywords

• allergic fungal sinusitis
• best corrected visual acuity
• computerized tomography
• functional endoscopic sinus surgery
• magnetic resonance imaging
• optic neuritis
• relative afferent pupillary defect