Spontaneous tension pneumocephalus in a patient with subdural empyema.

We report a 45-year old male who developed subdural empyema (SE) with tension pneumocephalus. The patient was admitted unconscious with tonic extensor response to pain. A "gas-forming" organism, Escherichia coli, was detected. Surgical evacuation of the pus and treatment with the appropriate antibiotic did not result in amelioration of his symptoms and the patient died. We identified a rare clinical situation when the SE cavity had a relatively large air loculus that was clearly related to gas-forming bacteria. It appeared that the patient had developed tension pneumocephalus related to the air produced by the pathogen. To our knowledge, this is the first report of a gas-forming organism in an abscess cavity that resulted in tension pneumocephalus and related symptoms.