What Is a Brain Abscess?
Neurological Health Data Verified

Brain Abscess - Causes, Symptoms, Diagnosis, and Treatment

Published on Nov 04, 2022 and last reviewed on Mar 17, 2023   -  5 min read


Brain abscess is a severe condition characterized by the accumulation of pus in the brain. Read this article to know more.


The brain is the master organ in the human body that controls many vital functions. It is a complex organ and weighs about three pounds in a healthy adult. The activity of the brain depends on messages from chemicals known as neurotransmitters. Diseases of the brain are generally life-threatening and require immediate medical attention. These conditions can range from epilepsy, brain infection, tumors, vascular disorders, stroke, mental disorders, Alzheimer's, etc.

What Is a Brain Abscess?

Brain abscess is a severe condition characterized by the formation of pus-filled swelling in the brain. It is potentially a life-threatening condition that occurs due to bacterial or fungal infection. An abscess causes swelling in the brain and might restrict the blood flow to the affected site. Additionally, brain abscesses might also put harmful pressure on the tissues.

The infections tend to occur in people with weak immune systems. The entry of bacteria or fungi can happen through a brain injury or injury somewhere in the body. It seems that microbes can also spread from ear, sinus, or tooth infections.

What Causes Brain Abscess?

The bacteria which cause brain abscesses belong to the anaerobic or mixed variety. For example, Streptococci and Staphylococci are involved in the infection after a head injury, neurosurgery, and endocarditis. Aspergillus and Toxoplasma gondii can cause brain abscesses in HIV (human immunodeficiency virus) patients.

The spread of infection can occur through:

1. Extension of infections in the skull (sinusitis, osteomyelitis, mastoiditis, etc.).

2. Wounds that penetrate deep into the head.

3. Microbes entering the bloodstream (bacterial endocarditis and congenital heart diseases).

4. Miscellaneous and unknown causes.

What Are the Signs and Symptoms of Brain Abscesses?

The symptoms of brain abscess develop several weeks after the infection.

The most common symptoms in adults include:

1. Mental disorientation, confusion, and decreased responses.

2. Decreased ability to speak or sense.

3. Personality and behavior changes.

4. Disturbances in the vision.

5. Nausea and vomiting.

6. Fever, chills, and weakness.

7. Photosensitivity (sensitivity to light).

8. Stiffness in the neck.

9. Headaches.

10. Seizures.

What Are the Symptoms in Babies and Young Children?

The symptoms are similar to that in adults; however, children may show other symptoms, such as soft spots on the head.

Other symptoms include:

1. Vomiting in a projectile way.

2. Crying with a high-pitched voice.

3. Stiffness in the limbs.

How Is a Brain Abscess Diagnosed?

Brain abscess is diagnosed based on clinical findings, patient history, laboratory, and imaging tests.

1. Medical History: The doctor will enquire regarding the recent history of infection, weak immune system, and other relevant questions related to the condition.

2. Blood Tests: A complete blood count helps check the levels of white blood cells, which increase in number during an infection.

3. Imaging Modalities: Scans such as CT (computed tomography) scan and MRI (magnetic resonance imaging) will determine the lesion's location, dimensions, and extent.

4. CT-Guided Aspiration: It is a type of biopsy where a needle is inserted into the abscess, and a sample of the pus is collected. This sample is then analyzed for specific microbes and other contents.

What Is the Treatment for Brain Abscesses?

A brain abscess should be treated immediately after the diagnosis. If not intervened early, it can lead to life-threatening complications. The choice and prognosis of the treatment depend on the following:

1. Size of the lesion (a conservative approach can treat smaller abscesses).

2. Number of abscesses present.

3. Infectious agents (viruses, bacteria, and fungi) of the abscess.

4. General and systemic health of the patient.

What Are the Treatment Options?

1. Medications: If the abscess is small, an intravenous antibiotic, antifungal, or antiviral drug would be sufficient. The smaller abscess might have to be drained before treating it with specific medication. The primary source of infection in the sinus, ears, or lungs should be addressed first.

2. Surgery: The abscess is drained and then removed carefully. This method might not be effective when there are multiple abscesses present. Surgery is recommended in the following circumstances;

  • Increasing pressure in the skull.

  • When the severity of the abscess does not resolve even after medication.

  • Presence of gaseous content in the abscess.

  • Risk of rupture of the abscess.

What Is the Procedure?

Surgeons perform a craniotomy, where an opening is made in the skull to access the lesion.

The steps of a craniotomy are:

  1. First, a small area of the scalp is shaved.

  2. A small piece of the skull bone is drilled to access the lesion.

  3. The abscess is either drained with a CT-guided needle or surgically removed.

  4. The bone is replaced with an artificial material, and the scalp is stitched.

  5. After the surgery, a short course of high-dosage corticosteroids may help relieve intracranial pressure and prevent complications.

  6. The doctor might also prescribe anticonvulsant medications to prevent seizures.

What Are the Complications Associated With Brain Abscesses?

The most common complications associated with brain abscesses are:

1. Reinfection and Recurrent Abscess - If the symptom seems to appear again and if there is a small chance of recurrence, inform your physician immediately. Recurrence is common in people with a compromised immune system.

2. Brain Damage - The abscess can cause permanent or temporary brain damage, especially if the diagnosis and treatment are delayed.

3. Epilepsy - The patient might experience repeated seizures or fits.

4. Meningitis - Infection of the meninges (protective layers of the brain) that requires immediate treatment.


Brain abscess is a severe condition characterized by the accumulation of pus-filled swelling in the brain. It is potentially a life-threatening condition that occurs due to bacterial or fungal infection. The symptoms of a brain abscess include headaches, behavioral changes, vomiting, seizures, fever, chills, etc. Therefore, early diagnosis and treatment are extremely important, as untreated brain abscesses can cause life-threatening complications. The treatment involves antibiotic therapy and surgery. Advances in the imaging modality have made diagnosis and treatment easy and approachable, thereby reducing mortality and morbidity.

Last reviewed at:
17 Mar 2023  -  5 min read




Comprehensive Medical Second Opinion.Submit your Case

Related Questions & Answers

What Specificities Declare a Person Brain Dead?

Article Overview: Brain death is when the brain stops functioning as a whole or when there is no possibility for a patient to gain consciousness. Read below to know more. Read Article

Introduction: Brain death creates hopelessness in anybody hearing it; also, it is such a sad thing to hear, right? When somebody is breathing only with oxygen support due to head trauma or conditions associated with the brain, there is a high chance that the person could be brain dead. Unfortunately...  Read Article

How to Cure Pseudomonas Infection?

Article Overview: This article discusses the symptoms, diagnosis, and treatment of Pseudomonas infection. This infection can affect the respiratory tract, heart, central nervous system, etc. Read Article

Talati Vidhi Hareshbhai
Talati Vidhi Hareshbhai

Introduction of Pseudomonas Infection Gessard first discovered this infection in 1882. Pseudomonas infection is one type of bacterial infection which is caused by Pseudomonas aeruginosa bacterium. Mostly normal people have this infection without knowing. It is mostly found in moist environment such ...  Read Article

Amebiasis - Causes, Risk Factors, Symptoms, Diagnosis, Treatment, and Prevention

Article Overview: Amebiasis is an intestinal disease caused by the parasite Entamoeba histolytica. Read the article to know more about amebiasis. Read Article

Jagdish Singh
Jagdish Singh
Medical Gastroenterology

Introduction: Amebiasis is an infection of the intestines caused by the microscopic parasite Entamoeba histolytica. It can affect both children and adults. Amebiasis occurs worldwide but is more commonly seen in developing countries due to poor sanitation and increased fecal contamination of water s...  Read Article

Popular Articles Most Popular Articles

Do you have a question on Brain Abscess or ?

Ask a Doctor Online

* guaranteed answer within 4 hours.

Disclaimer: No content published on this website is intended to be a substitute for professional medical diagnosis, advice or treatment by a trained physician. Seek advice from your physician or other qualified healthcare providers with questions you may have regarding your symptoms and medical condition for a complete medical diagnosis. Do not delay or disregard seeking professional medical advice because of something you have read on this website. Read our Editorial Process to know how we create content for health articles and queries.