HIV virus, by Dr.Guevara (medicine lessons)

HIV by Dr. Guevara; November 2013
The following is a description of classes (record the class and transcribed)
Microbiology, Virology section
School of Medicine - Universidad de Oriente - Ciudad Bolivar - Venezuela.
(translated to english by Google Translate)

1.- HIV
The Human Immunodeficiency Virus (HIV) belongs to:
Family: Retroviridae Genus: Lentivirus
Species: Human Immunodeficiency Virus.

There is a diversity, from the phylogenetic point of view, when grouping or distributing all members of this genre.
There are some who, from the point of view of the structure of the genes that encode the envelope, are similar and others that do not look alike. Based on this, several groups have been made: Group M, Group N and Group O.
-The point of view may be important, because it has seen something in the groups, especially Group M which is the largest, could have had the greatest capacity to generate resistance to antiviral drugs.
-With regard to the taxonomy exclusively in VIRUS if the species is not in Latin DO NOT SUBRAY, I saw it in cursive, because it is in Spanish as the case of the species: Human Immunodeficiency virus, it is in Spanish completely. Only the viral species is not underlined, nor is it in italics.
These viruses have the peculiarity that they are enveloped viruses, have a cylindrical capsule and are in this case: single chain RNA.
-Additionally has a reverse transcriptase that is responsible for reading this RNA and transformation into ARNemsajero and then in DNA to be able to make viral replication, this transcription is the opposite way. By this transcription, conversely, the opposite is read, a virus that is known as RETROVIRUS, due to the transcription that is from back to back.
-From the point of view of cellular tropism, they have tropism by: TCD4 lymphocytes, macrophages and especially those that have SR5 and CRXL4 receptors that are receptors for different types of proteins.

TRANSMISSION. Contagious Pathways

-Relationships: In sex not involved only penetration, involves contact with any type of genital secretion, to have oral sex with a person who is infected with HIV there is the possibility of infection. If you have a wound on your finger and it touches vaginal or urethral secretions, through that wound the virus can penetrate. It involves contact with contaminated secretions. Protected sex can also help prevent the person from getting infected with the Human Immunodeficiency virus, but that sex is protected from the beginning to the end.

Transplacental way: a mother can infect the fetus, or the sea because the mother acquires HIV during pregnancy, or is positive and gets pregnant. However, it is now known that if the mother at the beginning of the pregnancy, the treatment is offered, and the time for pregnancy is taken, there is a very high probability of more than 95% of the HIV-NEGATIVE child. But the mother needs treatment from the moment she is known to be pregnant.
-Using syringes and needles used by an infected person.
-Blood transfusions.

ROUTES OF NO CONTAGIO
-The kisses and the herpes.
-Sneezing, coughing, sharing glasses, etc. (Through the saliva does not spread HIV)
-Do not spread through insects.
-Injectable drugs with sterilized needles.
-The virus is very labile, before ultraviolet light, desiccation, any type of detergent, it is a virus that does not resist the environmental temperature, it does not resist being outside an organism, therefore it is not transmitted through contaminated contaminants, nor of clothes Nothing of that. It has to be by direct contact with secretions.

CLINICAL STAGES OF HIV INFECTION

This disease has several stages:
1.- First stage: when the infection starts and has the acute retroviral syndrome.
2.- Second stage: refers to a period of latency, where there is no type of clinical manifestation, but the individual is infected.
3.- Third stage: simply of the Acquired Immunodeficiency Syndrome (AIDS) that finally leads to death.

A differentiation must be made, between being infected and having the disease. It is one thing to be infected with the Human Immunodeficiency Virus (HIV) and another thing is to have AIDS, AIDS is the final stage of the disease. An infected person can be perfectly without problem, without any clinical manifestation, but as the disease progresses it will diminish everything that is immune, the TCD4 and TCD8 lymphocytes that are the targets of the virus, at the beginning enters a phase of immunocompromise and begins a series of opportunistic infectious diseases for later in the AIDS stage.

CD4 AND VIRAL LOAD.
They are the best prognostic markers of progression to AIDS in HIV patients.
-CD4
It reflects the current immunological capacity.
Predicts more accurately the short-term progression.
Predicts the development of symptomatic disease.
Correlates with the development of opportunistic infections.

-CARE VIRAL (NUMBER OF COPIES OF VIRUS THAT HAVE CIRCULATING IN THE BODY).
Predict the longer term progression.
Predict the response to treatment.
What happens when a person becomes infected?
The big problem with HIV is that there are many infected people who do not have any type of symptomatology, so a responsible person must constantly check their HIV status, obviously depending on their sexual activity.

An HIV test will not always turn out well, there are several circumstances:
-From the moment the person is infected up to 6 to 8 weeks, ALL available tests will be negative, but the person has the infection and is able to transmit it to another person. This period is known as window period, it is dangerous because the person apparently is negative, but transmits the disease.

After 6 to 8 weeks, the tests are positive and the antibodies that are circulating against the virus can then be detected.

The person has relationships with another infected person:
-From day 0 (zero), it will start uploading everything related to viral load (from 0 to 900 copies in the 4th - 5th week).

After the 4th - 5th week everything begins to descend. The viruses that are circulating in plasma will decrease and they will become practically undetectable after week 12, but the RNA will be circulating, since viruses are being made in the cells and part of that RNA escapes and It can be detected by molecular biology tests. Then the RNA copies of the virus will decrease.

What will happen to CD4 T lymphocytes?
They are the target of these viruses. From 1000 to 1200 per mm3 which is approximately the amount that you normally have, they begin to descend until you reach 400 - 500 and later they will recover their count without major problem.

CLINICAL MANIFESTATIONS
It can have different types of manifestations, in the first place it can have a viral syndrome, malaise, fever, asthenia, bone pain, muscle pain, joint pain that can last from 5 to 7 days.
Additionally it may have some manifestations at the level of the central nervous system such as Guillain - Barré Syndrome, this syndrome is not the Central Nervous System itself but the Peripheral Nervous System which is a peripheral Polyradiculopathy where there is involvement at the level of the roots of the motor nerves. , therefore the patient will begin to lose mobility and will make an ascending flaccid paralysis, and that flaccid paralysis can affect the breathing muscles and the patient can cause respiratory failure, which may require intensive therapy to ventilatory assistance.
-Facial paralysis
-Peripheral neuropathy that will cause pains in different parts of the body
-Sycosis

After the weeks go by the patient will have a clinical recovery, all symptoms will decrease; It's going to be apparently normal but it's going to have the virus circulating and the RNA copies of this virus. The count of the TCD4 lymphocytes is recovered a little. This is what happens in the acute retroviral syndrome.
Once this happens (it can last up to 3 months approximately), it will enter a phase of asymptomatic latency, it can last on average between 8 to 10 years if no type of treatment is placed on it.

During this period we will see:

A recovery of the TCD4 lymphocyte count
Then a progressive fall of your count; the magnitude of this fall will depend on the initial inoculum, then it may be more pronounced or it may be slower. If it is slower, it means that its latency phase will be longer, but if the fall is faster, the latency phase will be shorter.

There is considerable variation in progression, this involves passing from the latency phase to AIDS; that is to say of simply being infected to have AIDS. Rapid progressors are those that in less than 5 years pass through the latency phase and enter the AIDS period; the slow ones are those that can take up to 12 years before they make the period of AIDS.
The patient enters the period of AIDS when their TCD4 go down to the point where they are no longer able to provide an adequate functioning of cellular immunity.

What happens with viral load and viral RNA copies?
The viruses begin to actively replicate, the amount of detectable virus begins to rise and the number of copies of the circulating RNA begins to rise and in the end the patient makes a series of clinical manifestations, usually opportunistic infections that lead to death .

Time to develop the AIDS stage:
In homosexual men, approximately 8.9 years
13% of people at 5 years
51% at 10 years
54% at 11 years old.

CLINICAL INDICATORS OF THE AIDS STADIUM
Factors that indicate that the infected patient is passing to the AIDS stage:
Pneumocystis jiroveci pneumonia (pulmonary disease in immunocompromised patients)
Consumption syndrome (long-standing diarrhea, 3 weeks to 30 days, weight loss> 10%, fever> 30 days)
Esophageal candidiasis 18%
Tuberculosis 16%
Ocular CMV (eye involvement due to cytomegalovirus)
Kaposi's sarcoma (type of skin cancer that occurs in people who have altered their cellular immunity)
Herpes simplex (esophageal)
Cryptococcus meningeal
Cerebral toxoplasmosis
Isosporiasis

In practice many times we see patients who arrive with diarrhea of 3 or 4 weeks and do not take anything away and deny being HIV +. The patient is debuting with AIDS, is what is primarily seen.
The other thing we see sometimes is tuberculosis. There is a high association between HIV and tuberculosis, when looking for statistics, either from the country or global HIV statistics, one of the items that stands out is the HIV-TB coinfection; because if the cellular immunity is altered then the patient is not only prey for fungal infections but also for bacteria. Remember that both mycobacteria and fungi produce granulomatous type infections whose solution is primarily responsible for cellular immunity.

The other thing that we can see is that many times there are patients who debutan or with a meningeal cryptococcosis or a cerebral toxoplasmosis.
Then there are 4 key things, long-standing diarrhea, a meningeal cryptococcus, a cerebral toxoplasmosis and tuberculosis.

Currently, as part of a study protocol for a patient with tuberculosis, HIV must be tested to make sure it is not HIV +.
Usually patients arrive with Cryptococcus, for example: Patient of 25 or 30 years with meningitis, all studies are done and the report of the laboratory is encapsulated yeast, 99% of probability that the patient has AIDS, because cryptococcosis is controlled at a pulmonary normally by the immune system and from there it does not advance; unless the patient has received a very large inoculum of Cryptococcus yeast and the immune system can not completely control it.

Normally when a patient is receiving chemotherapy or radiotherapy is covered with antibiotics and antifungals to prevent opportunistic infections, since in these patients in all cells primarily leukocytes, counting them go to the soil (400 or 500 lecuocytes per ml3 blood) where normal is from 5000 to 6000; That is why antibiotics or antifungals are placed to prevent opportunistic infections.

Cerebral toxoplasmosis  the patient will arrive convulsing or with a sycosis episode and without any history of epilepsy, or drug use, or anything to which you can attribute that the patient is convulsing; it is not known what is happening, until a tomography is done, and calcifications are found in the cerebral cortex that is causing stimulation and is what causes seizures; The patient is HIV positive.

The fundus is one of the criteria, since these patients may also have some manifestations of infectious diseases at the ocular level.

DIAGNOSIS

The immunological tests in general lines, to detect IgM - IgG antibodies, or antigens that may be circulating, have been progressing and improving as the years have gone by. In fact, specifically for HIV screening we talk about Generation tests:
-First generation
-Second generation
-Third generation

Fourth generation (the current one); Until 3 years ago, only the Third Generation test was managed, which had a window period of 6 months, the person from the moment he became infected until the moment when the test was positive had passed 6 months. With the improvement of the generation in the tests that window period was reduced to 2 months, and in some circumstances a little less than two months. The improvement of the tests is something important and that must be taken into account.

The western blot test detects copies of the RNA that is circulating, upon reporting this positive test, the patient's infection is confirmed.

NOTES OF PROFESSIONAL INTEREST:

It is important to use double glove, because it is not the same to prick yourself with your bare hand, to prick yourself with a pair of gloves or with two pairs of gloves, because when having the gloves the needle goes through the gloves and cleans, and the probability that the virus reaches the body decreases exponentially. It is ideal to use nitrile gloves.
When a puncture with needle, or during a surgical intervention, a suture, also accidentally can be punctured or it can be cut with a scalpel that is using, the conducts that must arise immediately that there is an industrial accident are:

The patient does not leave until you take a blood sample to make HIV to that patient.
The one who suffered the accident must also become an HIV.
You have to talk to the person on duty in the emergency, they have the Emergency Treatment Kit; medications that must be taken for a period of two or one week, and subsequently

Perform the HIV test periodically as long as the patient has tested positive; If the patient came out positive and you are negative, you should still take your treatment and every three months you have to get HIV again to make sure it goes negative until the year. If the patient is negative and you are negative, the treatment is taken anyway.

-It is important the complete identification of patient (including place of residence).
-Do not perform breastfeeding when the mother is HIV positive because there is a virus out of breast milk.

There are no vaccines.
-An HIV positive person should not study medicine; but this is relative, since it depends if the person wants to be a surgeon, because it is a bit complicated because at any time during an operative act can be punctured or cut and thus infect the healthy patient. There are other branches of medicine that can be exercised normally by an HIV positive person.