HIV Flashcards
Name 2 suitable host cells of HIV infection? Why?
CD4+ T lymphocytes and macrophages
They have the correct CD4 receptors on the surface
When the viral nucelocapsid enters the host cell and breaks down what does it release?
3 essential replication enzymes
Integrase
Portease
Reverse transcriptase
Function of integrase?
Transfers viral DNA into cell nucleus and facilitates integration into host genome
Function of reverse transcriptase?
Reverse transcription of viral RNA to DS DNA
List 4 points HIV treatment can block the replication pathway
Fusion inhibitors block entry to host cell
Nucleoside inhibitors of non-nucleoside reverse transcriptase inhibitors inhibit reverse transcription
Integrase inhibitors inhibit integration of viral genome into host
Protease inhibitors
Describe CD4 levels after primary infection?
Rapid decrease then light increase as the HIV isn’t established yet, followed by a slow decrease over time
Consequences of reduced CD4 count?
Increased risk fo atypical/recurrent/prolonged infections
Increased risk of AIDs related cancers
Increased risk fo organ specific HIV related complications
Consequences of increase in viral load?
CD4 count falls, HIV related conditions increase and a infectivity increases
Describe symptoms in clinical stage I of HIV infection?
Asymptomatic
Swelling of lymph nodes (persistent generalised lymphadenopathy)
Describe symptoms in clinical stage II of HIV infection?
Weight loss, less than 10%
Angular chelitis (other minor mucocutaneous manifestations)
Herpes Zoster
Recurrent upper respiratory infections
Describe symptoms in clinical stage III of HIV infection?
Weight loss, more than 10% Oral hairy leukoplakia Oral candidiasis TB Severe bacterial infections
Describe symptoms in clinical stage IV of HIV infection?
Karposi’s sarcoma
HIV encephalitis
HSV
Candaiasis of lungs
What category of people tend to receive late diagnosis, why?
Heterosexual men living outside of London.
They aren’t educated, not enough testing
List 5 routes of acquisition of HIV?
Sexual intercourse Iv drug use Mother to child transmission Infected blood products Occupational
How to reduce sexual transmission of HIV?
Condoms, PREP (PEP)= pre-exposure prophylaxis = 2 drugs given before exposure
How to reduce mother to child transmission of HIV?
Avoid breastfeeding
Decrease mothers viral load below 100
PEP for baby
List 5 disease that should indicate a HIV test is required?
TB Bacterial pneumonia Encephalitis Kaposi's sarcoma Herpes Zoster Oral hairy leukoplakia Weight loss Hep B infection Neutropenia
When should treatment start?
As soon as diagnosed - do not wait for CD4 count to get low
Why should treatment be started as soon as possible?
Less AIDs related complications
Reduce all cause mortality
Reduced transmission
What is of note of the kind of drugs given to treat HIV?
At least 3 different drugs of at least 2 different classes - better barrier - targets more steps so more likely to be effective
What is HAART?
What are the aims of HAART?
Highly active anti-viral therapy
Inhibit viral replication
Present high genetic barrier to resistance (3+ drugs 2+ classes)
Allow Cd4 count to recover
List the possible targets for HAART?
Cell entry - co-receptor antagonism, fusion inhibitor
Enzyme inhibitor - reverse transcriptase inhibitor, integrase inhibitor, protease inhibitor
List 8 issues in HIV care
Late diagnosis Stigma Adherence to drug regime Interactions Partner notification and testing Prevention of transmission Management of co-morbitiies Conception and pregnancy planning
