Brain abscess 1 :- Causes

Brain abscess is a disease which occurs when our brain response to a an infection in the brain.

There are three main pathways through which the infection reaches our brain

1. An infection from some other part of the skull enters our brain.

2. Infection from some other part of our body travels through the bloodstream and enters our brain.

3. when the microbes such as bacteria and fungi enter the brain part of the skull directly from the outside when we have a trauma or an injury

Now lets elaborate on the three pathways through which the infection reaches our brain

From some other part of the skull

1. Sinusitis(An infection of the sinuses which is an air filled cavity inside the cheekbones, between the eyes at the nasal bridge, lower center of the forehead and behind the nasal cavity)
2.  Otis media (An infection from the nearby ear)

3.  Mastoiditis (An infection of a bone behind the eye)

From some other part of the body

Brain abscess is a very rare and a dangerous disease. Its rare because our body doesn't allow the germs, especially bacteria to easily enter the brain. This is because there is a blood brain barrier that doesn't allow these germs to enter our brain. But for some unknown reasons these pathogens are able to slip by the blood brain barrier and go on infecting the brain.

1. Infections from the lungs like pneumonia, bronchitis etc.

2. Pulmonary arterioveneous fistula - a rare disease in which the veins and arteries of the heart make abnormal connections with each other. This results in insufficient supply of oxygen to the blood and henceforth various organs of the body.

3.  Cyanotic heart disease- A conginental heart disease which results in insufficient supply of oxygen to the various organs of the body. Insufficient supply of oxygen to the brain means it is more prone to such infections

NOTE:- Our immune system has the power to fight off various infections. A person with a weakened immune system is much prone to an abscess as the antibodies wont be able to fight off the infections  

Subjected to a head injury or trauma

Some times we often get hit by hard substances like a cricket ball, rods etc. This results in the pathogens like bacteria and fungi directly entering our brain. Infection of the brain cells takes place which inter leads to the formation of an abscess

Development of pus

Now after the brain has been infected by one of the above mentioned causes, our immune system develops a membrane of healthy cells around these infected and dead cells. This creates a mass which gradually keeps increasing in size and then eventually it presses itself against the skull The skull being hard cannot expand aa a result of which it again exerts equal pressure on the mass. This causes damage to various blood vessels that supply to the brain.This leads to various neurological symptoms.

Now lets sum up everything in brief:-

1. An infection enters the brain

2. The immune system creates a membrane around the infected cells

3. The pus presses against the skull

4. The skull can't expand hence the blood vessels in the brain get damaged

5. The membrane around the infected cell is called an abscess