A subdural effusion is a collection of pus beneath the outer lining of the brain.

Causes

A subdural effusion is a rare complication of bacterial meningitis. Subdural effusion is more common in infants and in persons who have meningitis caused by Haemophilus influenzae.

Symptoms

• Bulging fontanelles
• Increased head circumference
• Lethargy
• Persistent fever
• Seizures
• Separated sutures
• Vomiting
• Weakness

Exams and Tests

There is often a recent history of bacterial meningitis. Tests include:

• CT scan of the head
• MRI scan of the head
• Ultrasound of the head

Treatment

Surgery to drain the effusion is often necessary. Rarely, a permanent drainage device (shunt) is needed to drain fluid. Antibiotics may need to be given through a vein.

Outlook (Prognosis)

Full recovery from a subdural effusion is expected. If neurological problems continue, they are generally due to the meningitis, not the effusion. Long-term use of antibiotics is usually not necessary.

Possible Complications

Complications from surgery include:

• Bleeding
• Damage to brain structures, which can lead to temporary or permanent brain and nervous system (neurological) problems
• Infection

When to Contact a Medical Professional

Call your health care provider if:

• Your child has recently been treated for meningitis and symptoms continue
• New symptoms develop