Occult clival chordoma initially unrecognized on MRI presenting with cerebrospinal fluid rhinorrhea: a case report

Cerebrospinal fluid (CSF) rhinorrhea most frequently results from traumatic or iatrogenic skull base disruption. In contrast, tumor-induced spontaneous CSF leaks and the subsequent development of purulent meningitis (PM) are relatively rare and pose significant diagnostic challenges.Case Presentation: A 39-year-old man presented with acute headache and fever following a two-month history of intermittent, clear unilateral rhinorrhea. Lumbar puncture confirmed PM, and brain magnetic resonance imaging (MRI) revealed left lateral ventricular empyema but no definitive skull-base mass. After achieving clinical stability with a two-week course of targeted antibiotics, the patient underwent endoscopic CSF fistula repair. Intraoperatively, a clival lesion was encountered; histopathological examination (characterized by physaliferous cells and brachyury positivity) confirmed the diagnosis of chordoma.

This case suggests that persistent spontaneous CSF rhinorrhea can be the initial manifestation of an occult skull-base tumor, even in the absence of clear findings on preoperative MRI. In patients with CSF leak complicated by meningitis, management must prioritize infection control while concurrently pursuing a thorough etiologic workup and timely surgical intervention to address both the fistula and any underlying neoplasm.