What does HIV stand for?
Human immunodeficiency virus
If untreated, what does HIV infection cause?
Acquired immunodeficiency syndrome
HIV infection is untreatable - true or false?
HIV is treatable and patients can go on to life an "almost-normal" life expectancy
What type of virus is HIV?
Retroviruses have which type of genetic material?
How does a retrovirus replicate?
Converts its RNA to DNA using reverse transcriptase
Inserts its DNA into the DNA of the host cell
So when the host cell undergoes transcription and translation, it produces new viral RNA
Virus also takes over host metabolism to produce new coats
Which receptor does HIV target?
Which immune cells have CD4 receptors?
Cells which ___ antigen to other immune cells tend to have CD4 receptors.
i.e antigen-presenting cells like macrophages and dendritic cells have CD4 receptors
Which molecules, found on CD4+ cells like macrophages and T helper lymphocytes, help these cells to present antigens to other immune cells?
What does antigen presentation by CD4 cells cause?
B cells, cytotoxic T cells, cytokines
i.e your adaptive immune response
How does HIV infection reduce the adaptive immune response?
Affects antigen-presenting CD4+ cells, stopping the activation of the immune system in response to pathogens
HIV infection gammies the immune system.
What does this render the patient susceptible to?
In untreated HIV infection, the count of CD4+ cells (increases / decreases).
CD4 cell count decreases
In untreated HIV infection, the viral load (increases / decreases).
viral load increases
A CD4 count of less than ___ cells / mm3 constitutes a risk of opportunistic infection.
< 200 cells / mm3
What syndromes do you develop in
a) Weeks 2 - 4
b) Years 9+
of HIV infection?
a) Acute HIV syndrome
Without treatment, how long do
with HIV survive?
a) 10 years
b) 1 year
So it's important to identify and diagnose it early
Which system spreads HIV around the body?
Around 2 - 4 weeks after HIV infection, what do 80% of patients present with?
Acute HIV syndrome
What is the presentation of acute HIV syndrome?
Rash - maculopapular, similar to meningococcal rash
Is acute HIV syndrome a chronic condition?
Resolves after a week - opportunity to diagnose HIV passes
Are patients with acute HIV syndrome infectious?
V much so
If untreated, during which time period are HIV patients asymptomatic?
Week 4 - Year 9+
During asymptomatic HIV infection, what happens to a patients
a) CD4 count
b) Viral load
a) CD4 count decreases
b) Viral load increases
c) Still infectious - can transmit via bodily fluids
What are two opportunistic respiratory infections which you need to know about re: HIV patients?
What is the presentation of pneumocystis jirovecci infection?
What is the presentation of pulmonary tuberculosis?
Chronic productive cough +/- haemoptysis
What are the antibiotic treatments for
a) pneumocystis pneumonia
a) Co-trimoxazole +/- steroids
b) 2 RIPE 4 RI - 2 months rifampicin, isoniazid, pyrazinamide and ethambutol, then 2 months rifampicin and isoniazid
What infection, related to cervical cancer, are patients with HIV more susceptible?