Rhinocerebral Mucormycosis Complicated with Cavernous Sinus Thrombosis and Collet-Sicard Syndrome: A Case Report

Rhinocerebral mucormycosis is an invasive fungal infection of the paranasal sinuses, orbits, and cranium, caused by saprophytic fungi of the order Mucorales. This infection spreads locally and rapidly in susceptible individuals due to the angio-invasive nature of the fungi. Infection spreading into the base of the skull can cause lesions of the jugular foramen and hypoglossal canal, leading to Collet-Sicard syndrome.
We report a 57-year-old woman who presented with fever, headache, vomiting for four days and acute loss of vision in the right eye on a background of long-standing diabetes. She had chemosis and proptosis of the right eye with blindness and complete ophthalmoplegia. There was facial sensory loss in the distribution of the ophthalmic and maxillary divisions of the trigeminal nerve. Non-contrast computerised tomography scan of the head showed right maxillary, sphenoid, and ethmoid sinus inflammation, with cavities filled with heterogeneous material. Subsequently, she developed right lower four cranial nerve palsies suggestive of Collet-Sicard syndrome. To our knowledge, this is the first reported case of Collet-Sicard syndrome due to mucormycosis in the global literature.