Brain abscess

• A brain abscess is a localised collection of pus in the brain parenchyma, usually caused by a bacterial or fungal infection.

• Relatively rare but can be life-threatening.
• Can occur at any age, but more common in young and middle-aged adults.

• Commonly results from the spread of infection from nearby structures, such as the ears, sinuses, or teeth.
• Haematogenous spread from a distant site of infection (e.g., endocarditis).
• Direct infection following head trauma or neurosurgery.
• Immunocompromised states increase the risk.

• The infection leads to an inflammatory response, collection of pus, and formation of a capsule.
• The abscess can cause increased intracranial pressure, brain tissue displacement, and can lead to herniation if untreated.

• Headache (most common symptom), fever, nausea, and vomiting.
• Focal neurological deficits depending on the abscess location.
• Altered mental status or seizures in severe cases.

• MRI with contrast is preferred for better delineation of the abscess.
• CT scan can also be used, especially in emergency settings.
• Blood cultures and cultures from primary sources of infection.
• Stereotactic aspiration may be necessary for both diagnosis and treatment.

• Antimicrobial therapy is the cornerstone of treatment. Empiric antibiotic therapy should be broad-spectrum and adjusted based on culture results.
• Surgical intervention (aspiration or excision) may be necessary, especially for larger abscesses or those not responding to antibiotics.
• Management of raised intracranial pressure is critical.

• Meningitis
• Neurological deficits
• Sepsis
• Death 

• Depends on the size and number of abscesses, the organism responsible, the patient’s immune status, and how quickly treatment is initiated.
• Early diagnosis and treatment improve outcomes.

• A brain abscess is a rare condition characterised by a localised collection of pus in the brain parenchyma. 
• Headaches are the most common presenting symptom. Other presenting clinical features include fever, nausea, vomiting and focal neurological deficits.
• Management includes antimicrobial therapy and surgical intervention where necessary.
• Early diagnosis and treatment are important to improve outcomes and prevent complications.

Bokhari, M.R. and Mesfin, F.B. (2020). Brain Abscess. [online] PubMed. Available at: https://www.ncbi.nlm.nih.gov/books/NBK441841/.