Okay in our video series on infectious medicine in this video we’ll be talking about human immunodeficiency virus. HIV we’ll discuss how is it transmitted we’ll discuss what is the presentation of HIV and how you dig nose it. How does it progress to AIDS we’ll discuss the treatment of HIV and AIDS. First of all, human immunodeficiency virus as its name implies is a virus that attacks the body’s immune system specifically. The CD4 T cells destroy the CD4 T cells resulting in acquired immunodeficiency syndrome AIDS. AIDS occurs when the CD4 count drops less than 200 millimeters Cube normal CD4 count in the body is between 500 to 1500-millimeter cube in AIDS.
The CD4 count is less than 200 milli meters per Cube HIV has two types of HIV one HIV and two HIV which is most common worldwide. HIV 2 is present in West Africa and it has a slow disease progression coming to the transmission of HIV. HIV is transmitted mainly through sexual load 80 percent of the cases are due to the sexual. Rule and needle sharing can cause a 0.6 percent chance per needle stick in IV drug users needle stick injury in healthcare workers can cause a 0.36 percent chance of getting. HIV vertical transmission from mother to child during birth has a 5 to 15 percent chance of transmission of HIV from mother to baby.
There are low chances of transmission the viral load copies are less than 400 per ml so proper treatment of HIV can cause a reduction in the chances of transmission by reducing the viral copy viral load in the body. Coming to the presentation of HIV. HIV can present in three different stages first stage is the acute infection where the person acquires an infection and gets the symptoms. The acute symptoms after that are in the second stage when the patient’s CD4 count starts to drop down and drops to less than 500 patient starts developing illnesses but those illnesses are not. AIDS-defining illnesses illnesses are non-aids defining illnesses and the third stage where the CD4 count drops down to less than 200 in that condition patient starts to develop illnesses that are AIDS.
Defining that patient has now developed immunodeficiencies and room and less than 200 CD4 count results in illnesses that are AIDS-defining illnesses now acute infection after the patient acquires. HIV patients can develop fewer fatigue headaches myalgia’sathergias generalized known tender lymph adenopathy within two weeks this acute presentation is very vague a presentation just like the infectious moon on nucleuses virus so it cannot be detected very easily at this stage but as soon as the patient starts to develop immunodeficiency the CD4 counts dropped down the patient starts to develop illnesses that are AIDS-defining and if those AIDS.
Defining illnesses, you must check for HIV some patients may have generalized maculopapular rash GI symptoms, and sore throat now in the second stage patient’s CD4 count starts to drop down starts to drop from 500 and patients start to develop known AIDS-defining illnesses known AIDS-defining illnesses include chronicsubfiberal temperature persistent generalized lymph denopathychronic diarrhea greater than one-month oral candidiasis remember oral candidiasis is a known AIDS. Defining Illness but esophageal candidiasis is an aid defining illness HPV related problems like anal warts and shingles so these are all the known AIDS.
defining illnesses after that patient’s CD4 count drops down to less than 200 and the patient starts to develop infections that give you a hint that the patient has developed immunodeficiency and if that patient has developed immunodeficiency patient is infected with HIV if theCD4 count is less than 200 patient can develop pneumocystis pneumonia if theCD4 count is less than 100 patient is at risk of getting cerebral toxoplasmosis meningitis esophageal candidiasis if theCD4 count is less than 50 patient can develop disseminated Mac infection mycobacterium AVM cellular infection patient can develop CMV infection CMV retinitis as CMV colitis and when the CD count starts to drop down below these you need to give profile access to the patient and we will discuss that what drugs are given in the profile axis when
CD4 counts start to drop down now coming to the diagnosis of HIV diagnosis of HIV involves two things first screening of the patients with HIV and then performing the confirmatory test on patients with HIV the screening is done with fourth-generation antibodies and antigen essay antibodies against HIV. HIV antibodies AGG IGM against HIV are detected in blood as well as HIV p24antigen of the HIV is also detected so you are detecting two thing-shiv-p24 antigens and antibodies in blood to detect HIV so that is the fourth-generation antibody-antigen essay.
Eliza is a test that can only detect antibodies it cannot detect antigens but fourth-generation antibody-antigen essay can detect both antigens andante bodies now if the test comes out to be positive you have to perform the confirmatory test you perform HIV one HIV two antibody differentiation immune oassayfourth generation antibodies essay can detect the HIV antibodies but it cannot differentiate that whether it is HIV or is one or HIV 2 for that purpose you need to perform another test confirmatory test that is HIV one HIV two antibody differentiation immunosa which tells you that whether it is HIV 1 or HIV 2. and if that comes out to be positive it means that the patient has HIV and HIV infection is confirmed if that comes out to be negative it means that you can rule out HIV.
HIV is negative and if that test comes out to be negative but you still have a high suspicion that the test might be a false negative you can go for plasma HIV RN testing in plasma HIV RNA testing you done you do nucleic acid amplification testing in which you do PCR of the RMA you do PCR of the HIV RNA and detect the virus present in the body and it is done only if you have a very high suspicion the confirmatory test comes out to be negative in that case you can go for this test so for screening fourth generation essay is done and after that for confirmation to differentiate we do HIV one HIV two antibody different iationimmunoassayan important Point to remember.
HIV one Western blood is an outdated test and it is no longer recommended for confirmation of HIV coming to the screening of infants in infants you cannot use antibody tests any test that involves the detection of antibodies is not done in infants why because if the mother is infected with HIV and you want to see whether that infected mother has passed on HIV to her infant to her son or her daughter you cannot do antibody tests because antibody. Giant bodies can affect the placenta and the patient. Will have IGG antibodies in the blood even though the HIV RNA HIV will be negative so you will get false positive results because of the presence of maternalistic bodies maternal IGG antibodies are present in the blood of the infant.
So you do antibody tests on an infant infant you can screen them by HIV one RNA testing by PCR by net so the question comes out for the screening of an infant less than 18 months in the infant you have to choose the option of HIV RNA testing PCR or net you do not choose any tests that contain the detection of antibodies because antibodies will be positive even if the infant has an infection or even if the infant does not have an infection now coming to the treatment of HIV and AIDS to understand the treatment of HIV you need to understand the antiretroviral drugs mechanisms first of all this is a CD4 cell and virus HIV gains entry through ccr5 and cxcr4receptors virus enters through these receptors of white blood cells and viral RNA is converted to viral.
DNA by an enzyme reverse transcriptase now viral DNA enters the nucleus and in the nucleus, it gets integrated into the nucleus resulting in the formation of RNA copies those RNA copies produce proteins those proteins and RNA copies are assembled and then t are released outside by enzymes proteases so proteases cause the release of these RNA copies and RNA proteins into the other cells of the body and these daughter viruses are released so virus gets entry to the receptors the RNA gets replicated to the DNA DNA gets integrated to the nucleus where it forms RNA copies it forms proteins and these proteins and copies are assembled and released by proteases.
Now coming to the mechanism of action of the drugs this reverse transcriptase is inhibited by nucleoside reverse transcriptase inhibitors nrti and known nuclear side reverse transcriptase nrti so these drugs inhibit reverse transcriptase proteases are inhibited by protease inhibitors and in the nucleus the integration of DNA into the nucleus is inhibited by integrase inhibitor you can easily understand the mechanisms of antiviral therapy in antiviral therapy what we do is that we have a backbone therapy and with that backbone therapy we add other drugs in the backbone we have always have two nucleoside reverse transcriptase inhibitor in the backbone we always have two nucleosides reverse transcriptase. Inhibitors with which we can add one non-nucleoside reverse transcriptase inhibitor or you can add one protease inhibitor that is called a boosted therapy or you can also add one integrase inhibitor.
These are all the combinations that can be used for the treatment of antiretroviral therapy but remember the backbone is always made up of two nucleosides reverse transcriptase and if it is with which you can add any other drug so according to the 2021 CDC guidelines we have two nucleoside reverse transcriptase Inhibitors plus one integrase inhibitor in two nucleosides reverse transcriptase inhibitor you can use xenophobic 25 mg per already daily with altretamine another nucleoside reverse transcriptase inhibitor 200 mg per only once daily and you can add one integrase Inhibitors big Tech raver 50 mg per already once daily it comes with a single tablet formulation that is a bit RV one tablet per oral one steady you can also use a combination of twenties a Becca Veer lamivudine with one integrase inhibitor the loot trigger wheel and this formulation comes with one drug called as a triumph.
One tablet daily may be used in pregnancy but its Contra indications include HLA b5701 positive people it’s the be aware drug that is contraindicated in hlab5 701 because it causes hypersensitivity reaction we also have a two-drug combination where there is one NRTI with one integrase Inhibitors that include lamivudine with the loot trigger Veer so it comes with the name of Donato one tablet daily and it should not be used if the patient also has HBV co-infection now coming to the post-exposure profile axis in post-exposure profile axis if someone got a needle stick injury with an HIV-infected person and you need to give post-exposure profile access to that person, you can give the no forward 300 mg per orally once daily with empty seta mean 200 mg per orally once daily with Rel Tegra we’re 400 mg per hourly twice TV and it is given for four weeks. It is given within 72 hours of exposure it must be given within 72 hours of exposure to HIV pre-exposure profile access is indicated for high-risk groups.
High-risk groups like males having sex with men especially the receptive ones inconsistent condom use sexually transmitted infections within six months IV drug users have zero discordant partners in which the couple has HIV infection and the other one does not have HIV infection in that patient you need to give free exposure profile access it is given to know for 300 mg only once daily with Empress it has been 200 mg per only one steady now coming to HIV during pregnancy also the breastfeeding topic HIV in pregnancy must be treated within the duodenal is the main drug is an exam you get a question about HIV in pregnancy always choose the option with the drugs.
They do good in with any two other entry retroviral drugs remember the only antiretroviral drug that is contraindicated in pregnancy is severe HIV-positive mothers should avoid breastfeeding because it can cause transmission of the virus to the baby now coming to the profile axis as CD4 count will start to drop down in HIV patients when the CD4 count starts to drop down patient is high at high risk of developing these infections you need to give profile access to prevent this infection when the CD4 count is less than 200 patients are at risk of pneumocystis pneumonia you need to give trimethoprim sulfur meth oxazole is the first line if the patient is allergic you can give oral depth soon if the patient has G6PD you can give oral at over corn, if the CD4 count is less than 150 patient is at risk of histoplasmosis you need to give a track on azole if the patients.
CD4 count is less than 100 patient is at risk of cerebral toxoplasmosis for which you need to give trimethoprim sulfur meth oxazole double strength and if the CD4 count is less than 50 patient is at risk of mac and you need to get azithromycin 1200 mg once per week or you can give Clarithromycin or rifle butane these are all the profile axes that you have to give when the CD4 count starts to drop down you need to start these drugs now coming to some important points if the patient has renal impairment avoid knowing forward because it causes renal damage. If the patient has co-infection with hepatitis B give anthracite limited the no forward because they will kill the Hepatitis B virus as well as the HIV in pregnancy use 014 now when you have started the antiretroviral therapy you need to monitor the patient with HIV RNA viral load the cool is that the patient has undetectable viremia when you have started antiretroviral therapy and there should be a rise in CD4 count remember the HIV RNA viral load will drop down quickly but the CD4 count rise.
Will take some time, in summary, we talked about HIV and AIDS the types of HIV the transmission talked about acute presentation about known arm-defining illnesses we do talk about screening with uh fourth generation essay HIV one HIV two antibody differentiation screening in infants with HIV-1 RNA testing we talked about the replication of virus we talked about the antiretroviral therapy the combinations with which the two notes are the backbone with combination with one other drug we talked about big tar vi we talked about prior Mac we talked about Lovato we talked about the exposure profile axis given within 72 hours we talked about the pre-exposal profile x’s and their indications we talked about reducing in pregnancy if evidence contraindicated in pregnancy HIV positive mother should avoid breastfeeding we talked about the profile access given for all these conditions we talked about monitoring of patient with HIV RNA viral load when you have started the antiretroviral therapy if you liked my video please click on the Subscribe button and check out my other videos on infectious medicine and emergency medicine the link of those videos is given in the description below.
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