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An 84-year-old woman with new onset mutistic behaviour and a fever of 40°C was found to have marked neck stiffness without any focal abnormalities. There was no immunosup-pressive status. The cranial CT showed intracranial air in the posterior fossa (Figure 1A). Cerebrospinal fliud revealed a granulocytic pleocytosis (1,057/µl) with considerably elevated protein (7,080 mg/l) and lactate (14.4 mmol/l). The microbiological tests confirmed gram-positive diplococcae. Intensive care management and antibiotic therapy (ceftriaxone and ampicillin) was implemented. Examination of the ears showed moderate right-sided mastoiditis. Conservative treat-ment was advised and the patient recovered within 3 weeks. Pneumocephalus is a rare complication of pneumococcal meningitis which is still a serious infection with high mortality and morbidity [1–3]. This case reminds us that pneumococcal meningitis can occur even in the elderly and that intracranial air suggests a leak from the paranasal sinuses or the mastoid (Figure 1B). A conservative treatment regimen led to com-plete resolution of the air and a good clinical recovery. Key points • Pneumococcal menigitis can occur in the elderly. • Pneumocephalus is a complication of pneumococcal men-ingitis. • Mastoiditis can be the source