HIV Flashcards
What is the mode of transmission of HIV?
specific body fluids - blood, semen, genital fluids, and breast milk
- unprotected sex w an infected person
- sharing infected syringes and needles (IV drug users)
- Mother-to-child transmission during preg, at birth or through breast-feeding
- transfusion w contaminated blood and blood products
Who should be tested for HIV?
- IV drug users
- unprotected sex w multiple partners
- MSM
- CSW
- Persons treated for STDs
- recipients of multiple blood transfusion
- people who have been sexually assaulted
- preg women
How to diagnose HIV infection?
- serum antibody detection
~ HIV enzyme immunoassay antibody tests
~ Western Blot - HIV RNA detection/ quantification (viral load): PCR
What are the different stages of HIV presentation?
A) Acute (Primary) HIV Infection
B) The Asymptomatic Stage
C) Persistent Generalised Lymphadenopathy
D) AIDS and Related Conditions
What S&S are present in Acute (Primary) HIV Infection?
soon after contracting HIV, flu-like illness with swollen lymph nodes, fever, malaise and rash lasting about 2-3wks
Are there any S&S for The Asymptomatic Stage?
No, stage persists for many years
What presentation is seen in Persistent Generalised Lymphadenopathy?
Persistent unexplained lymph node enlargement in the neck, underarms and groin for > 3mths
What is the presentation/ seriousness when HIV has progressed into AIDs and related conditions?
- AIDS = CD4 <200/mm3 or presence of AIDS-defining diseases
- Advanced stage of disease and person succumb to infections by unusual organisms that the uninfected person can resist
- organs affected: lungs, eyes, GIT, nervous system, skin
- systemic smx like fevers, unexplained weight loss and diarrhoea are also common
- rare cancers (e.g. Lymphoma and Kaposi sarcoma) may be found
What are the primary goals of anti-retroviral therapy?
- reduce HIV-associated morbidity and mortality
- prolong duration and quality of survival
- restore and preserve immunologic fn
- maximally and durably suppress plasma HIV viral load
- Prevent HIV transmission
What are the surrogate markers in HIV?
- CD4
- Viral load
How is CD4 used to indicate presence of HIV?
- CD4 (T-lymphocyte) count (healthy) = 500-1200 cells/mm3
- most impt lab indicator of immune fn in HIV-infected patients
- also strongest predictor of subsequent disease progression and survival
- use to determine urgency for initiating antiretroviral therapy (now, once person has HIV, initiate therapy)
- use to assess response to antiretroviral therapy
~ assessed at baseline and every 3-6mths after treatment initiation, every 12mths after adequate response
~ adequate CD4 response is defined as an inc in CD4 count in range of 50-150 cells/mm3 during 1st yr of therapy - use to assess the need for initiating or discontinuing prophylaxis for opportunistic infections: e.g. prophylaxis for pneumocystis pneumonia is started when CD4 cells are <200 cells/mm3
How is viral load used to indicate presences of HIV?
- Viral load (plasma HIV RNA) = amt of virus in plasma
- most impt indicator of response to antiretroviral therapy and can be useful in predicting clinical progression
- viral load measured before initiation of therapy and within 2-4wks (not later than 8wks) after treatment initiation or modification, thereafter, every 4 to 8 weeks until viral load suppressed
- effective regimen generally achieve viral suppression (i.e. undetectable HIV RNA level) by 8-24 wks
- In patients on stable regimen and suppressed viral load, monitoring can be done evry 3-6mths
When to start ART?
- ART recommended for all HIV-infected ind, regardless of CD4 cell count, to reduce morbidity and mortality associated with HIV infection
- ART also recommended for HIV-infected ind to prevent HIV transmission
- when initiating ART, impt to educate pts regarding benefits and considerations regarding ART, and to address strategies to optimise adherence
- case-by-case basis, ART may be deferred because of clinical and/or psychosocial factors, but therapy should be initiated ASAP
Benefits of earlier treatment?
- maintenance of a higher CD4 count and prevention of potentially irreversible damage to the immune system
- Decreased risk for HIV-associated complications that can sometimes occur at CD4 counts >350cells/mm3, incl TB, non-Hodgkins’s lymphoma, Kaposi’s sarcoma, peripheral neuropathy, and HIV-associated cognitive impairment
- Decreased risk of non-opportunistic conditions, incl CVD, renal disease, liver disease, and non-AIDS-associated malignancies and infections
- Dec risk of HIV transmission to others, which will have positive public health implications
Limitations of earlier initiation?
- treatment-related side effects and toxicities
- drug resistance because of incomplete viral suppression, resulting in loss of future treatment options
- transmission of drug-resistant virus in patients who don’t maintain full virologic suppression
- less time for pt to learn about HIV and its treatment and less time to prepare for need for adherence
- increased total time on medication, with greater chance of treatment fatigue,
- increased cost
