AIDS

by Dr. Aurora Orzechowzki


AIDS means Adquired Immune-Deficiency Syndrome, a disease with no cure until today, it is progressive and mortal.

To better understand what's this disease about, it is necessary to first understand some other concepts:

THE IMMUNOLOGIC SYSTEM.

It's the defense system of the body, against foreign and harmful organisms, consists of different groups of cells, called linfocytes; among these cells are the ones called CD4, who are the ones directing the defense, sending chemical signals to other linfocyte groups to wipe out the harmful agent, called antigen.

THE HUMAN IMMUNE-DEFICIENCY VIRUS

This virus, attacks precisely to the CD4 cells, introducing its genetic code into the CD4's genetic code, forcing them in this way to reproduce the virus instead of CD4 cells, killing them at the same time.

AIDS

When the virus has manage to considerably destroy the immune system leaded by the CD4 cells we say there's a immune-deficiency and that is acquired because is not congenit, meaning that is not hereditary, although sometimes some people are born with it because they acquired it from an infected mother.

This transmission, from an infected mother to her baby, can happen during pregnancy, at birth or during lactation.

When a significative immune-deficiency is present, there are certain signs or symptoms that in conjunction are called syndrome and that are characteristic of this illness; for example, opportunistics infections and cancers.

RNA

Ribonucleic acid is the place where the genetic code of the virus is found, in other words, its hereditary characteristics, necessary to replicate themselves.

Normally, in nature, the DNA or deoxyribonucleic acid sends messages to RNA, but in the case of HIV, the virus manages to reverse the direction of the flow of information, sending its messages of its RNA to the cell's DNA, and because of this important characteristics it is called Retrovirus.  The virus inserts its genetic information into the reproduction mechanism of the cell, thanks to the reverse transcriptase. 

Human immune-deficiency virus belongs to the family of lentivirus, which means that it can remain in a latency state inside the organism during long periods of time, to activate when suitable conditions emerge for that purpose.  However, we now know that the HIV never remains inactive, because starting from its entry to the organism begins to reproduce itslef in the lymphatic ganglions, causing the death of thousands of millions of cells per day.

MANIFESTATIONS OF THE DISEASE

When the immune system has been considerably diminished by the HIV, infections and cancers called opportunistic appear, because they take advantage of this condition of the organism to attack and develop.

DETECTION

To know for sure that the virus exists in the organism it is necessary to take the Elisa test, that consists in searching for the antibodies that the body produces to fight the HIV.  When this test results positive, a confirmatory test called Western blot must be done.

CELL COUNT

Once confirmed the presence of the virus in the organism, it is convenient to have a laboratory test to know the amount of CD4 cells that exist by cubic millimeter.  Normal parameters go from 500 to 1,200 cells, so the result will indicate how much harm has been caused by the HIV.

Until recently it was believed that, in light that the virus remained latent for a while, it wasn't necessary to give treatment until the cell count was of 500 or less. 

Now, knowing that the virus acts starting from its entrance to the organism, what's advisable it to give anti-viral drugs starting from the very moment in which is detected.

It is recommended to start treatment to prevent opportunistic infections when the number of CD4 cells has droped to 200 or less.

VIRAL LOAD

This laboratory test allows us to know the amount or viral particles present in the blood, which is an indicator of the damage that can be expected causes the virus.  Unlike the CD4 cell count, that indicates harm done.  In other words, based on the results of the viral load, it can be predicted how fast the disease is going to advance and unfortunately how soon can death can get to the person. 

ANTI-RETROVIRALS

Today, there are drugs available to stop the viral replication, depending of the moment of its action are called Reverse Transcriptase Inhibitors, Protease Inhibitors and, in a future, the Integrase Inhibitors.

New drugs can turn AIDS from a mortal disease to a cronic disease, like diabetes actually is.



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