Nocardial clival osteomyelitis secondary to sphenoid sinusitis: an atypical skull base infection.

Clival osteomyelitis is a life-threatening complication of untreated malignant otitis externa or paranasal sinus infection. Although various pathogens have been implicated, to our knowledge, primary nocardial clival osteomyelitis has never been reported. We describe a 74-year-old woman who presented with headaches, abducens and hypoglossal nerve palsies, facial numbness, photophobia, and neck stiffness. Imaging revealed a heterogeneous mass within the sphenoid sinus with clival extension. The lesion was extirpated via a binostril endoscopic endonasal transsphenoidal approach. Histopathological and microbiological examination revealed a nocardial source. Clival osteomyelitis associated with sphenoid sinusitis should be included in the differential diagnosis of progressive skull base lesions in the setting of an underlying infection. Early recognition and intervention with antibiotics and surgical debridement is essential in the management of this rare entity.