Indolent orbital apex syndrome caused by occult mucormycosis.

The chronic or indolent presentation of rhino-orbital mucormycosis, as defined by the presence of symptoms for more than 1 month before diagnosis, is extremely unusual. A 45-year-old man with stable diabetes presented with a right orbital apex syndrome and minimal ethmoid and sphenoid sinusitis. Progression was indolent, and the diagnosis was not made until 7 weeks after admission, when a third biopsy was prompted by new cavernous sinus and carotid artery thromboses. Mucormycosis was found. The patient improved on amphotericin B (2 g) and strict blood glucose control. A remarkable aberrant regeneration of the right oculomotor nerve was seen following treatment. He remains free of active disease 4 years later. Orbital symptoms in well-controlled diabetics, which may even remain stable for weeks and lack direct signs of tissue invasion, should raise the suspicion of mucormycosis.