Sudden-onset, non-traumatic large volume pneumocephalus following presentation of acute bacterial meningitis

Area of Science:

• Neurosurgery
• Infectious Disease
• Neuroradiology

Background:

• Skull base defects, often resulting from surgical resections for tumors like sinonasal undifferentiated carcinoma, can predispose patients to serious intracranial complications.
• Delayed presentation of complications years after initial surgery highlights the importance of long-term patient monitoring.

Observation:

• A 30-year-old male with a history of sinonasal undifferentiated carcinoma presented with acute meningitis and bacteremia due to Streptococcus pneumoniae.
• Brain MRI revealed an encephalocele, and subsequent CT head venogram identified a large pneumocephalus originating from a post-surgical skull base defect.

Findings:

• The patient experienced a relapse of neurological symptoms (headache, altered mentation) despite initial antibiotic and corticosteroid treatment.
• Surgical intervention, including external ventricular drain placement and pterional craniotomy with skull base packing, was required to manage the pneumocephalus and associated complications.

Implications:

• Skull base defects pose a significant risk for life-threatening conditions, including bacterial meningitis and pneumocephalus, even years after the primary surgery.
• Clinicians must maintain a high index of suspicion for delayed cranial surgical defects in patients with relevant surgical histories presenting with neurological symptoms.