Podcast
Questions and Answers
Which of the following mechanisms of action is associated with Integrase Strand Transfer Inhibitors (INSTIs) in the treatment of HIV?
Which of the following mechanisms of action is associated with Integrase Strand Transfer Inhibitors (INSTIs) in the treatment of HIV?
- Preventing the fusion of the HIV virus with the host cell membrane by blocking gp41.
- Inhibiting the protease enzyme, preventing the maturation of new viral particles.
- Directly inhibiting reverse transcriptase, thus halting the conversion of HIV RNA into DNA.
- Blocking the HIV enzyme integrase, thereby preventing the integration of viral DNA into the host cell's genome. (correct)
A patient with HIV is starting treatment with abacavir. What crucial screening test must be performed before initiating this medication, and why?
A patient with HIV is starting treatment with abacavir. What crucial screening test must be performed before initiating this medication, and why?
- Renal function tests, due to the risk of Fanconi syndrome.
- CD4 count, to assess the current stage of HIV infection.
- Liver function tests, to rule out pre-existing hepatic impairment.
- HLA-B*5701 testing, due to the risk of a potentially fatal hypersensitivity reaction. (correct)
Why are protease inhibitors (PIs) no longer considered first-line treatment options for HIV?
Why are protease inhibitors (PIs) no longer considered first-line treatment options for HIV?
- They have been found to be ineffective against newer strains of HIV.
- They are associated with significant side effects, including metabolic syndrome and drug interactions. (correct)
- They require intravenous administration, making them less convenient for patients.
- They directly interfere with the action of integrase, an enzyme not present in all HIV subtypes.
Which antiretroviral drug is administered via injection and is known for causing injection site reactions?
Which antiretroviral drug is administered via injection and is known for causing injection site reactions?
Which monitoring parameter is most crucial for the early detection of treatment failure in a patient undergoing antiretroviral therapy (ART) for HIV?
Which monitoring parameter is most crucial for the early detection of treatment failure in a patient undergoing antiretroviral therapy (ART) for HIV?
Which of the following should be avoided when a patient is taking an integrase strand transfer inhibitor (INSTI) such as dolutegravir?
Which of the following should be avoided when a patient is taking an integrase strand transfer inhibitor (INSTI) such as dolutegravir?
A patient who is also positive for Hepatitis B should be counselled not to stop which of the following HIV medications without consulting their doctor?
A patient who is also positive for Hepatitis B should be counselled not to stop which of the following HIV medications without consulting their doctor?
Which of the following is the primary mechanism by which cobicistat enhances the effectiveness of other antiretroviral medications?
Which of the following is the primary mechanism by which cobicistat enhances the effectiveness of other antiretroviral medications?
A patient taking Efavirenz reports experiencing vivid dreams and occasional moments of confusion. What is the most appropriate course of action?
A patient taking Efavirenz reports experiencing vivid dreams and occasional moments of confusion. What is the most appropriate course of action?
A patient on antiretroviral therapy exhibits an elevated serum creatinine level during a routine check-up. Which medication could potentially contribute to this laboratory abnormality?
A patient on antiretroviral therapy exhibits an elevated serum creatinine level during a routine check-up. Which medication could potentially contribute to this laboratory abnormality?
Flashcards
HIV Entry
HIV Entry
HIV binds to CD4 and chemokine receptors (CCR5/CXCR4) then fuses with the host cell membrane.
Reverse Transcription
Reverse Transcription
HIV RNA is converted into DNA.
HIV Integration
HIV Integration
Integrase inserts viral DNA into the host genome.
Replication
Replication
Signup and view all the flashcards
Assembly & Budding
Assembly & Budding
Signup and view all the flashcards
Maturation
Maturation
Signup and view all the flashcards
Integrase Inhibitors (INSTIs)
Integrase Inhibitors (INSTIs)
Signup and view all the flashcards
NRTIs
NRTIs
Signup and view all the flashcards
NNRTIs
NNRTIs
Signup and view all the flashcards
Protease Inhibitors (PIs)
Protease Inhibitors (PIs)
Signup and view all the flashcards
Study Notes
- HIV enters host cells by binding to CD4 and chemokine receptors (CCR5/CXCR4), then fuses via gp41.
- Viral RNA is converted into DNA by reverse transcriptase
- Viral DNA is inserted into the host genome by integrase
- The host cell transcribes and translates viral proteins
- Immature virus particles form and exit the host cell
- Protease cleaves proteins, making the virus infectious during maturation
HIV Treatment (ART)
- First-line treatment includes 1 Integrase Inhibitor (INSTI) + 2 NRTIs
- Combination drugs contain multiple HIV drugs for convenience - e.g., Biktarvy, Triumeq, Dovato
Integrase Strand Transfer Inhibitors (INSTIs)
- Drugs include Dolutegravir, Bictegravir, Raltegravir, Elvitegravir
- Mechanism: Blocks integrase, preventing HIV DNA integration into the host genome.
- Side effects: Muscle damage (↑ creatine kinase), depression/suicidal thoughts
- Caution: Avoid antacids (reduce drug absorption)
Nucleoside Reverse Transcriptase Inhibitors (NRTIs)
- Drugs include Tenofovir (TDF, TAF), Emtricitabine (FTC), Lamivudine (3TC), Abacavir (ABC), Zidovudine (ZDV)
- Mechanism: Stops viral DNA synthesis by causing chain termination
- Side effects: Lactic acidosis, liver enlargement, bone loss (esp. TDF), kidney damage (Fanconi syndrome)
- Caution: HLA-B*5701 test before giving abacavir (risk of fatal hypersensitivity)
- Tenofovir and Lamivudine also treat hepatitis B so do not stop them suddenly if HBV+
Non-Nucleoside Reverse Transcriptase Inhibitors (NNRTIs)
- Drugs include Efavirenz, Doravirine, Etravirine, Nevirapine, Rilpivirine
- Mechanism: Directly inhibits reverse transcriptase
- Side effects: Rash, liver issues, high cholesterol, severe psychiatric effects (esp. Efavirenz—vivid dreams, depression, hallucinations)
- Caution: QT prolongation (heart risk)
Protease Inhibitors (PIs)
- Drugs include Atazanavir, Darunavir, Ritonavir, Lopinavir
- Mechanism: Blocks protease, stopping virus maturation
- Side effects: Metabolic syndrome, liver damage
- Caution: No rifampin (for TB) with PIs—use rifabutin instead
- Note - Protease Inhibitors are not first-line anymore
Entry/Fusion Inhibitors
- Fusion Inhibitor (gp41 blocker): Enfuvirtide, causes painful injection site reactions
- CD4 Post-Attachment Inhibitor (Monoclonal Antibody): Ibalizumab is for multidrug-resistant HIV (not well tolerated)
- Note - Entry/Fusion Inhibitors are for Resistant HIV and not first-line
Boosters
- Cobicistat boosts Atazanavir/Darunavir
- Side effect: Increases serum creatinine
Key Monitoring
- Monitor HIV viral load to detect treatment failure early
- Monitor CD4 count to track immune function
- Monitor kidney/liver function for drug toxicity
- Monitor for side effects such as bone loss, metabolic issues, and mental health changes/decline
Crucial points
- Missing doses can cause drug resistance, so take meds as prescribed
- INSTIs are now first-line treatment
- Check for HBV before stopping NRTIs due to risk of HBV flare-up
- Protease inhibitors are not first-line anymore due to side effects and drug interactions
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
