A brain abscess occurs when infected material accumulates in the tissue of the brain. 

Also known as a cerebral abscess, a brain abscess is a pus-filled region of infected tissue in the brain. A brain abscess is typically caused by a bacterial infection, although fungi and parasites are possible causes of brain abscess too. 

It’s the body’s immune response to isolate the infectious material that creates the mass of the abscess, but this also causes inflammation and can put pressure on the brain. 

Frequently, in up to as many as 50% of cases, a brain abscess is a complication of a nearby infection, such as a sinus, dental or ear infection. Infections can also reach the brain via the bloodstream, with those with compromised immunity at greater risk.

What are its symptoms?

Brain abscess symptoms can develop slowly, sometimes over weeks, or they may develop rapidly. It’s estimated that in up to two-thirds of brain abscess patients, signs escalate to the point of requiring hospitalisation in two weeks or less. 

Brain abscess symptoms include:

  • Headache, usually severe and localised to a specific part of the head
  • Drowsiness
  • Fever
  • Mood and cognitive changes. These may include confusion, memory loss and increased irritability
  • Seizures
  • Vision changes
  • Neurological problems including issues with speech, movement and coordination. Loss of muscle function may occur, usually on one side of the body
  • Decreased sensation
  • Nausea and vomiting
  • Stiffness of the neck

How is it diagnosed? 

A physical examination and thorough medical history taking into account any recent infections or causes for a suppressed immune system may be enough for a doctor to suspect an abscess, after which the diagnosis will usually be confirmed with a CT (computed tomography) which can frequently detect the presence of a brain abscess. 

A magnetic resonance imaging (MRI) scan may also be ordered in cases where a more detailed image of the brain is needed. 

Blood tests can alert doctors to signs of dangerous infection that could be responsible for the brain abscess or a biopsy may be performed to determine the causative organism.

What are your treatment options? 

A brain abscess is life threatening and should be treated as a medical emergency.

Brain abscess treatment may require surgery or in some cases, such as when there are multiple abscesses or the abscess is too deep in the brain, medication alone. Intravenous antibiotics or antifungals being used to address the causative organism and a flexible tube called a shunt may be used to remove fluid build-up around the brain. 

Where surgery is needed it might be a simple fluid aspiration, whereby a small hole is drilled in the skull and the pus is removed with a needle and syringe, or a more invasive craniotomy (in which a section of the skull is removed and replaced post-surgery) may be required to drain the abscess.

Can it be prevented? 

Brain abscesses cannot always be prevented directly but you can reduce your chances of developing the condition by swiftly and adequately responding to infections that may put you at risk. 

It’s essential to always take antibiotics as prescribed following any illness or medical procedure and to alert your doctor as soon as any complications seem to arise.

The accuracy of this information was checked and approved by physician Dr Thomas Blake in May 2016