ICD-11

A focal suppurative process of the brain parenchyma, the intracranial or spinal epidural or subdural space, and less commonly the spinal cord parenchyma. The suppurative process is most commonly associated with bacterial infection, and occasionally with fungal, protozoal, or parasitic infection. Brain abscesses develop most commonly by spread from a contiguous infected site (ear, paranasal sinuses, mastoid air cells, teeth), craniofacial osteomyelitis, and following open head trauma or previous neurosurgical procedure. Haematogenous spread from purulent pulmonary infections, bacterial endocarditis, or other sites of infection can also cause brain abscess. Patients with intracranial abscess present with variable combinations of headache, altered mental status, focal deficits, and seizures. Fever may be present. Patients with intraspinal abscess present with variable degrees of paraparesis or quadriparesis, sensory impairment below the level of the lesion, altered sphincter function, and back pain. The diagnosis is made by CT or MRI imaging, and may be confirmed by histological examination and culture of the abscess material following neurosurgical drainage. Lumbar puncture is usually contraindicated.

A condition of the cranial cavity, caused by an infection with a bacterial, viral, or fungal source. This condition is characterised by a focal accumulation of purulent material within the cranial cavity. This condition may present with fever, headache, and focal neurological deficits.

A focal suppurative infection within the cranial cavity, including the epidural and subdural spaces, or in the brain, brainstem or cerebellum. The abscess is typically surrounded by a vascularised capsule. Cerebritis describes a nonencapsulated brain abscess. The infective agent may be bacterial, fungal, or parasitic. The signs and symptoms are variable but typically present as an expanding mass lesion, over a variable period of time, with headache, fever, and a focal neurologic deficit. Seizures may occur. Diagnosis is made by neuroimaging. Microbiologic diagnosis is made by gram stain and culture of abscess material.