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

Granulomatous amebic encephalitis

Overview

This is a very serious disease which takes place in people with compromised immune systems. Its caused due to the inflammation of the brain and the spinal chord. This is a very rare disease that is quite fatal.

Causes

This disease is caused by a parasite called acanthamoeba. Its a free living microorganism that is found almost anywhere. Many people might get exposed to this species of the phylum protista but there are very  few chances of the person being infected by this microbe. Our immune system doesn't allow it to cause infection but sometimes the parasite escapes and causes collateral damage to our brain. Massive inflammation of our

 brain takes place and the chances of survival go as down as 2 percent.

Other sorts of encephalitis

Encephalitis is usually caused by a viral infection . Like, the herpes simplex virus (causes cold sores and genetal herpes) mumps virus, chickenpox virus. In countries like U.K infection due to herpes simplex virus is very common. Elsewhere in the world agents carry these viruses. For eg. mosquitoes which carry Japanese B encephalitis virus.; ticks which carry European tick borne virus etc. 

Viruses such as measles, mumps viruses don't necessarily cause encephalitis but when these enter our bloodstream, they can reach  the brain and may lead to some damage.

Symptoms

The symptoms of GAE are usually drowsiness, mental confusion lack of  concentration and other neurological problems.

Treatment with an example

Antiviral drugs can be used for the treatment of GAE. Lets have a look at this with an example

One of the worst cases of GAE were seen in a young boy in the U.S. He loved playing hockey and wanted to get selected for nationals. He worked hard day and night but unfortunately he didn't get selected. The sole reason being his lack of concentration. Days passed by and his condition got worse. His parents took him to the nearby hospital and to there dismay there child was suffering from GAE. The doctors there had never seen such a serious case of encephalitis in their career. It got worse with time and they had to pit him under coma to stop the inflammation. Months passed by but there were no results.

Doctors use other methods

In order to wake the boy from coma, the doctors had to make the use of steroids. Eventually  the boy got cured and was healthy again.

Note:The use of steroid is a  very risky business, you may or may not survive