Background: Isolated sphenoid sinusitis and abscess formation is a rare entity, which can lead to misdiagnosed or improperly treated patients and an unfavorable outcome. Invasion of the skull base and cavernous sinus usually causes cranial nerve palsies, suggesting a neoplasm at the initial presentation.
Case description: A case of isolated abscess in the sphenoid sinus is reported. The complete destruction of the clivus and its unexceptional radiological data, in addition to the absence of clinical and laboratory evidence of infection, led us to misdiagnose a possible clival chordoma during preoperative evaluation. The patient underwent an endonasal-transsphenoidal procedure for diagnosis and surgical removal. Surgical drainage and prolonged antimicrobial treatment resulted in complete clinical recovery.
Conclusion: Its close proximity to vital structures and slender bony structures may allow the infection to disseminate, with serious neurological complications. On the other hand, the variable clinical presentations and radiological data usually cause delayed or missed diagnosis in these cases. This emphasizes the importance of documentation of this unusual entity and its radiological manifestations.