HIV Flashcards
Detail the genome of HIV.
Diploid (2 molecules of RNA)
What are the 3 structural genes the HIV genome codes for?
env- gp120, gp41
gag- capsid protein (p24)
pol- reverse transcriptase, protease, integrase
HIV binds CD4 as well as a coreceptor, what coreceptors is it able to bind?
CCR5
CXCR4
What genotype confers HIV immunity?
CCR5 Δ32 homozygote mutation
How is the diagnosis of HIV made?
ELISA (rule out test, high sensitivity low specificity)
if ELISA is positive,
Western Blot
What defines AIDS?
CD4 count below 200
HIV + with AIDS defining condition
When can ELISA and Western blot be negative even though a person is infected with HIV?
First 2 months of infection
When can ELISA and Western blot be positive even though a person is not infected with HIV?
Newborn to mother with HIV
What is the function of gp120?
Attachment to host CD4 cell
What is the function of gp 41?
Fusion and entry
What are Human Endogenous Retroviruses?
Family of viruses in our genome with elements of DNA that are similar to exogenous retroviruses.
Vertical transmission.
May provide benefits.
May be implicated in cancer/autoimmune disease.
(area of ongoing research)
What are AIDS defining cancers?
Kaposi sarcoma
Non-hodgkin lymphoma
Cervical cancer
Over time AIDS defining cancer incidence has decreased, however, all HIV associated cancers have not shown the same trend. What accounts for this finding?
Improved therapies have increased life of patients with HIV leading to increased incidence of non AIDS defining cancers.
Should HIV positive individuals who develop cancer be treated with HAART during chemotherapy?
Yes
What diseases are caused by HTLV-1 (Human T cell Lymphotropic virus)?
T cell leukemia/lymphoma
Uveitis
HTLV-1 Associated Myelopathy (HAM)
What are the clinical manifestations of T cell lymphoma?
Cutaneous lesions
Hypercalcemia (lytic bone lesions)
Hepatosplenomegaly
Lymphadenopathy
What blood smear finding is characteristic of T cell lymphoma?
Lymphocytes with “4 leaf clover” nuclei
What protein is coded for by HTLV-1 that is a potent activator of NFκB which enhances lymphocyte growth and survival?
Tax
What populations/regions are most effected by HTLV-1 infection?
Japan
West Africa
Caribbean
What information is gained from a plasma HIV RNA level?
Extent of viral replication
Describe the illness of acute HIV infection.
Mononucleosis-like illness with or without aseptic meningitis
Occurs 2-3 weeks after HIV exposure
When is the risk of HIV transmission the highest?
Acute infection
seroconversion
What does PrEP stand for?
Pre-Exposure Prophylaxis
What is the approved drug therapy for PrEP?
Tenofovir
Emtricitabine
(Truvada)
(2 NRTIS)
