HIV Flashcards
HIV is a _____________
Retrovirus
HIV-1 and HIV-2 … Which is more transmissible?
HIV-1
When should you consider HIV-2?
Pts from West Africa and/or AIDS patients with and indeterminate or negative HIV, as the tests may not pick it up
What is the time to seroconversion in HIV?
Most patients seroconvert to positive HIV serology within 4 to 10 weeks after exposure using newer diagnostic tests, and ≥95 percent seroconvert within six months [27-29]. The median time from exposure to positive serology in one study was 63 days (uptodate)
Currently, as divided by CD4 status: CD4 500: 1.19 years; CD4 350: 4.19 years; CD4 200: 7.93 years. (Pubmed: “Time from human immunodeficiency virus seroconversion to reaching CD4+ cell count thresholds…)
Blood exposure and sex are the risks for acquiring an HIV infection. Name some factors that increase risk of infection
Herpes, Trichomonas, Smoking
A pt is newly diagnosed with HIV infection. What is something you’ll want to know about the virus BEFORE beginning treatment?
Genotype
HIV is arranged in an icosahedral symmetry structure. The outer capsule surrounds RNA dimers. The proteins of this capsule are called capsid proteins (CA) and the major capsid protein is _______
p24 -This can be measured in the serum to detect early HIV infection
How do you determine whether or not a pt has AIDS?
HIV infection plus one or more of the following: CD4 count <200; a CD4+ T-cell percentage of total lymphocytes of less than 15%; or an AIDS-defining illness
What are the AIDS-defining illnesses?
Candidiasis of bronchi, esophagus, trachea or lungs; Coccidioidomycosis that has spread; extrapulmonary Cryptococcosis, Cryptosporidiosis for longer than 1 month, CMV outside of the liver, spleen or lymph nodes, HIV-related encephalopathy, Herpes simplex including ulcers lasting more than a month or bronchitis, pneumonitis or esophagitis, Histoplasmosis, Isosporiasis, Kaposi’s sarcoma, Lymphoma that is Burkitt type, immunoblastic or that is primary and affects the brain or central nervous system, Mycobacterium avium complex or disease caused by M kansasii, Mycobacterium tuberculosis, Pneumocystis pneumonia, progressive multifocal leukoencephalopathy, Salmonella septicemia that is recurrent, Toxoplasmosis of the brain, Wasting syndrome caused by HIV, invasive cervical cancer, recurrent pneumonia
What are CD4 counts in normal, healthy individuals?
~ 1000 cells/uL blood
In HIV-infected pts, how fast do CD4 counts decline?
by about 60 cells/uL blood/year
A 24 y.o. woman with HIV is diagnosed with MAC infection. She is started on a treatment regimen of clarithromycin with ethambutol. She needs to be educated that which of the following is a potential complication of this therapy? A. Anemia B. Azotemia C. Methemoglobinemia D. Mucositis E. Optic neuritis
E - Optic neuritis is associated with the use of ethambutol. Anemia is associated with many of the drugs used to treat AIDS-related opportunistic infections, including TMP/SMX, pentamidine, amphotericin B, ganciclovir, and valganciclovir. Amphotericin B is associated with azotemia and trimethoprim with methemoglobinemia. Trimetrexate can cause mucositis.
The American College of Obstetricians and Gynecologists (ACOG) recommends which of the following regarding delivery to prevent HIV transmission to the infant?
A. Cesarean delivery only for those women who have not received HAART during therapy.
B. Cesarean delivery if the infant has not been delivered within 3 hours of membrane rupture
C. Determination of type of delivery based on maternal viral load
D. Scheduled cesarean section at 38 weeks’ gestation
D
A 32 y.o. man who is HIV+ has a seizure. In the E.D., he is confused and unsure of what happened. His partner reports that he had been complaining of HA in the days preceding the event. CT scan of the head demonstrates 5 peripheral contrast-enhancing lesions. What is the most likely Dx?
A. AIDS dementia complex
B. Central nervous system lymphoma
C. Cryptococcal meningitis
D. Progressive multifocal leukoencephalopathy
E. Toxoplasmosis
E. The most common space-occupying lesion in pts with HIV is toxoplasmosis. This condition may present with HA, focal neurologic deficits, seizures, and/or mental status changes. The typical appearance on brain imaging is that of multiple contrast-enhancing lesions in the periphery, particularly the basal ganglia. CNS lymphoma is more typically a single lesion. AIDS dementia complex is a Dx of exclusion, without a characteristic appearance. Cryptococcal meningitis is made by examination of CSF. PML imaging shows nonenhancing white matter lesions without mass effect.
Which class of antiretroviral drugs is most likely to affect serum lipid profiles?
A. Entry inhibitors
B. Integrase inhibitors
C. Nonnucleoside reverse transcriptase inhibitors
D. nucleoside/nucleotide reverse transcriptase inhibitors
E. Protease inhibitors
E. Protease inhibitors are most likely to increase cholesterol and triglycerides; thus lipid profiles should be monitored carefully in patients taking them.
A surgical PA suffers a deep puncture wound during surgery on an HIV+ pt. The pt, who is on a multi-drug regimen, has a viral load of 120,000 copies. Which of the following drugs is contraindicated for the PA because of its potential for hepatotoxicity in the setting of HIV prophylaxis? A. Abacavir B. Indinavir C. Lamivudine D. Nevirapine E. Zidovudine
D. Nevirapine should be avoided for HIV prophylaxis as reports have linked it to hepatotoxicity in the prophylactic setting.
Which of the following vaccines is contraindicated in a person with HIV infection and a low CD4 count? A. Herpes zoster B. Inactivated influenza C. Measles D. Pneumococcal E. Tetanus-diptheria
A - The HZV vaccine is contraindicated in HIV+ persons who have evidence of immune suppression. The inactivated influenza vaccine should be given annually. Although measles is a live vaccine, it appears to be appropriate for an HIV+ person who has no protection against the measles. The pneumococcal and DTP vaccines form an important part of health-care maintenance for HIV+ persons.
A 36 y.o. woman with HIV is admitted with new-onset seizures. The CT scan of the head reveals multiple ring enhancing lesions of the brain. Which of the following is the best therapy for the likely condition? A. Rifampin, isoniazid, ethambutol B. Ganciclovir C. Penicillin D. Sulfadiazine with pyrimethamine
D
How does a ‘protease inhibitor’ (PI) work on HIV?
Protease is a vital HIV enzyme that cleaves gag and pol proteins from their larger precursor molecules (post translational modification). Protease deficient HIV virions can not form their viral core and are non-infectious. Therapy with protease inhibitors increases CD4 cells and reduces HIV levels.
Lopinavir
Protease inhibitor (1st generation)
Indinavir
Protease inhibitor
Nelfinavir
Protease inhibitor
Amprenavir
Protease inhibitor
Ritonavir
Protease inhibitor
How do ‘integrase inhibitors’ work on HIV?
Integrase inhibitors inhibit the enzyme integrase, which is responsible for integration of viral DNA into the DNA of the infected cell.
Atazanavir
Protease inhibitor
Darunavir
Protease inhibitor
Fosamprenavir
Protease inhibitor
Saquinavir
Protease inhibitor
Tipranavir
Protease inhibitor
Raltegravir
Integrase inhibitor
How do Non-Nucleoside reverse transcriptase inhibitors (NNRTI) work?
Non-Nucleoside reverse transcriptase inhibitors (NNRTI) inhibit reverse transcriptase by binding to an allosteric site of the enzyme; NNRTIs act as non-competitive inhibitors of reverse transcriptase.
Delaviridine
Non-Nucleoside reverse transcriptase inhibitor (NNRTI)
Efavirenz
Non-Nucleoside reverse transcriptase inhibitor (NNRTI)
Etravirine
Non-Nucleoside reverse transcriptase inhibitor (NNRTI)
Nevirapine
Non-Nucleoside reverse transcriptase inhibitor (NNRTI)
How do the Nucleoside reverse transcriptase inhibitors (NRTI) and Nucleotide reverse transcriptase inhibitors (NtRTI) work?
NRTIs and NtRTIs work to inhibit reverse transcription by acting as competitive substrate inhibitors
Abacavir
Nucleoside/nucleotide analogue (NRTI)
Didanosine
Nucleoside/nucleotide analogue (NRTI)
Emtricitabine
Nucleoside/nucleotide analogue (NRTI)
Lamivudine
Nucleoside/nucleotide analogue (NRTI)
Stavudine
Nucleoside/nucleotide analogue (NRTI)