An unusual case of infective pneumocephalus: case report of pneumocephalus exacerbated by continuous positive airway pressure

Pneumocephalus, illustrated by air in the cranial vault is relatively infrequent and generally associated with neurosurgery, trauma, meningitis and barotrauma. However cases of spontaneous non-traumatic pneumocephalus remain rare. While the relationship between continuous positive airway pressure (CPAP) and atraumatic pneumocephalus has been previously reported, to our knowledge the rare presentation associated with sinus wall osteomyelitis has never been described. We summarize here the case of a 67-year-old woman’s acute presentation of Streptococcus salvarius infection after a sudden drop in her consciousness. The patient was brought to hospital by family reporting a one week history of sudden deterioration, cognitive decline, and lethargy. The patient presented with reduced arousal, cognitive function (Glasgow Coma Scale: 10, Abbreviated Mental Test Score:CS, 0 AMTS), and no history of trauma. Computed Tomography (CT) imaging was ordered and identified a significant pneumocephalus with no cranial defect. Further investigations acknowledged possible sinus or middle ear disease, which was highlighted by the discovery of S. salivarius by polymerase chain reaction (PCR) and potentially exacerbated by the use of nocturnal continuous positive airway pressure (CPAP). The patient made a complete recovery by eliminating likely causative factors and long term regimental antibiotics administration. This case highlights a rare neurological presentation of S. salivarius infection with a mixed aetiology of spontaneous pneumocephalus. This case features an atypical complication associated with CPAP use, and to our knowledge is the first case to be associated with sinus wall osteomyelitis. Recognition of the clinical features and risk factors for spontaneous pneumocephalus –while rare—serve to broaden our clinical index of suspicion when presented with patients experiencing neurological deficit. Information from this case may also aid in improving prevention, early diagnosis, and future management.