HIV Flashcards
1
Q
What is the end result of an HIV infection?
A
AIDS
2
Q
People with treated HIV have a reduced life expectancy. True or false?
A
False
- Near normal life expectancy
3
Q
What kind of virus is HIV?
A
Retrovirus
4
Q
What is a retrovirus?
A
When RNA is transcribed it uses reverse transcriptase enzyme which doesn’t have proof reading ability and makes lots of mistakes. This enzyme turns RNA -> DNA
5
Q
Which type of HIV is responsible for the global pandemic of HIV?
A
HIV-1
group M
6
Q
HIV is a multi-system disease. True or false?
A
True
7
Q
Name 3 modes of transmission of HIV
A
Sexual
Parenteral
Vertical
8
Q
Which mode of transmission is most common?
A
Sexual
9
Q
Who are the most common group of people affected by HIV in the UK?
A
Men who have sex with men (MSM)
10
Q
Name 3 factors which increase the sexual transmission risk?
A
Anoreceptive sex (MSM)
Concurrent STI
Genital ulceration
11
Q
Parenteral transmission - name 3 examples
A
Injection drug use
Infected blood products
Iatrogenic
12
Q
It is only possible to acquire HIV from injecting drug use if….
A
You are sharing needles
13
Q
What are the 3 ways which vertical transmission can occur?
A
In utero
During delivery
Breast feeding
14
Q
Where is the global burden of infection?
A
Sub saharan Africa
15
Q
Who is more likely to have UNDIAGNOSED HIV (M/F) and why?
A
Males
- women are picked up in antenatal screening
16
Q
Which ethnicity is it more common in?
A
Black African
17
Q
What is the target site for HIV?
A
CD4+ receptors
- it is here that HIV links to the host cell
18
Q
CD4 is found on the surface of a variety of cells including …
A
T helper lymphocytes (CD4+ T cells)
Dendritic cells
Macrophages
19
Q
What happens to CD4+ T cells in HIV
A
Reduction of CD4+ cells as they are caught up in lymphoid tissue and not produced as much
20
Q
What is the normal CD4+ Th cell count
A
500-1600 cells/mm3
21
Q
At what CD4 count is there risk of opportunistic infection?
A
<200 cells/mm3
22
Q
What happens to CD8+ T cells in HIV
A
There is over production
- but they are dysregulated so this increases the susceptibility to viral infections
23
Q
HIV is all about immunosuppression and there is no immune activation. True or false?
A
False
- mainly about immunosuppressionbut there is immune activation due to chronic inflammation in the blood which occurs as a result of the gut becoming more leaky
24
Q
What is the natural course of the infection? (4 stages)
A
Primary infection
Asymptomatic infection
Opportunistic disease
Death
25
Describe the immunopathogenesis
1. Virus is transmitted
2. Virus attaches to a mucosal CD4 cell and binds to one type of co-receptor (CCR5 or CXCR4)
3. HIV Virus fuses with cell and infects it
4. Virus is transported to regional lymph nodes
5. Virus is disseminated to other sites in the body
26
There is a ____ day window from when the virus enters the body to when it reaches the regional lymph nodes? What is significant about this?
3 day
27
Which enzyme cleaves HIV chains ?
Protease
28
Primary HIV infection - when do most patients present with symptoms ?
2-4 weeks after infection is established
29
Primary HIV infection - clinical features
```
Very non specific
Fever
Skin abnormalities - rash
Myalgia
Sore throat (pharyngitis)
Headache
```
30
Primary HIV infection - risk of transmission is HIGH/LOW ?
High
31
Primary HIV infection - what happens to CD4+ Th count?
It declines rapidly
32
Asymptomatic HIV infection - everyone is asymptomatic. True or false?
False
- lots of people still experience symptoms such as:
- mucosal candidiasis
- seborrheic dermatitis
- diarrhoea
- fatigue
- lymphadenopathy
33
Asymptomatic HIV infection - definition
There is ongoing viral replication of the infection but it is sub-clinical (in some cases)
34
Opportunistic infections (OI) - definition
An infection caused by a pathogen that does not normally produce disease in a healthy individual.
It uses the opportunity of a weakened immune system to cause disease
35
OI - Pneumocystis pneumonia (PCP) - causative organism
Pneumocystis jiroveci
36
OI - Pneumocystis pneumonia (PCP) - clinical features
Gradual onset
SOB
Dry cough
37
OI - Pneumocystis pneumonia (PCP) - CXR findings
```
Initially normal
Interstitial infiltrates (looks like PO)
```
38
OI - Pneumocystis pneumonia (PCP) - diagnosis
BAL
Immunofluoresence
Low CD4 count < 200
39
OI - Pneumocystis pneumonia (PCP) - management
High dose co-trimoxazole
40
If patient has low CD4+ Th count and a +ve diagnosis for HIV but they do NOT have PCP, what do you give as prophylaxis?
Low dose co-trimoxazole
41
TB related conditions are less common in patients with HIV. True or false?
False
| - more common
42
OI - cerebral toxoplasmosis - how do you get it ?
From cats
43
OI - cerebral toxoplasmosis - causative organism
Toxoplasma gondii
44
OI - cerebral toxoplasmosis - clinical features
```
Headache
Fever
Focal neurology
- cerebral abscesses
Seizures
Reduced consciousness
Raised ICP
```
45
```
Reduced visual acuity with floaters.
Abdominal pain
Diarrhoea
PR bleding
With a CD4 count < 50
What is the opportunistic infection?
```
CMV
46
OI - herpes zoster
Multidermatomal zoster
| Recurrent
47
HIV can cause cognitive impairment. True or false?
True
48
What does the JC virus cause?
Progressive multifocal leukoencephalopathy
49
OI - PML - clinical features
Rapidly progressing
Focal neurology
- confusion
- personality change
50
Name 3 AIDs related cancers
Kaposi's sarcoma
Non-hodgkins lymphoma
Cervical cancer
51
Kaposi's sarcoma - organism
Human Herpes Virus 8
52
Kaposi's sarcoma - pathology
Vascular tumour with violet coloured papules
53
Kaposi's sarcoma - clinical features
Violet papules on skin
54
Kaposi's sarcoma - management
HAART
| Chemotherapy - if visceral involvement
55
Non-Hodgkins lymphoma - causative organism?
EBV
56
Cervical cancer - causative organism?
HPV
57
HIV testing - who should be tested
Universal testing in high prevalence areas (opt out)
High risk groups
- MSM
- Female partners of bi- men
- PWID
- Partners of people with HIV
When HIV falls within the DD x
People in certain clinical settings
58
HIV testing - Should be offered to everyone in which clinical settings?
```
TOP services
GUM clinics
Drug dependency services
Antenatal services
Assisted conception services
```
59
HIV testing - obtaining consent
Explain to patient they are being offered an HIV test and why
- "to make sure immune system is working properly"
Benefits of testing
- improve long term health
- protect partners
Reassure confidentiality
60
HIV testing - if patient refuses, what should you do?
Document refusal
61
HIV testing - incapacitated patient - you must consent relative beforehand. True or false?
False
62
HIV testing - incapacitated patient - what would be the ideal solution?
If safe, wait until the patient regains capacity
63
HIV testing - Name 3 markers that are used to detect infection?
Viral RNA
Antigen
Antibody
64
HIV testing - what is the first marker to become positive?
Viral RNA
65
HIV testing - which antigen are you testing?
p24
66
HIV testing - antibody testing - how long is the window period?
20-25 days (will be -ve within these days and will only be +ve after the window period_
67
HIV testing - 3rd generation HIV tests
HIV-1 and HIV-2 antibody
+ve result anywhere from 3 months onwards
Very sensitive/specific
68
HIV testing - 4th generation
Combined antibody and antien (p24)
69
HIV testing 3rd generation / 4th generation has a shorter window period?
4th generation (+ve result anywhere from 4 weeks onwards)
70
HIV testing - rapid - when can you get results?
Within 20-30 mins
71
HIV testing - rapid - advantages
Simple to use
No anxious wait
Good sensitivity
No venipuncture required
72
HIV testing - rapid - disadvantages
Expensive
| Quality control
73
Can Rapid HIV testing be relief on in early infection?
NO
74
Recent infection testing algorithm (RITA) - what is it used for?
To identify if an infection occurred within preceding 4-6 months
75
Recent infection testing algorithm (RITA) - is it reliable?
No
| - large margin of error
76
Investigations
- CD4 count = high/low
- Platelet count = high/low
- LFTs = high/low
```
CD4 count = Low
Platelet count = Low
LFTs = high
```
77
Management (general)
HAART
78
Name 3 targets for anti-retroviral drugs?
Reverse transcriptase
Integrase
Protease
79
HAART - how many drugs are used?
A combination of 3 drugs from at least 2 drug classes to which the virus is susceptible
80
HAART - why use a 3 drug combo?
It prevents resistance
81
HAART - 3 drug combo is given as 3 separate tablets. True or false?
False
| - co-formulated and given in 1 tablet
82
HAART - aims
Reduce viral load to undetectable
Restore CD4 Th count
Reduce morbidity and mortality
83
HAART - NRTI - definition
Nucleoside analogue reverse transcriptase inhibitors
84
HAART - NRTI - examples (4)
Abacavir
Emtricitiabine
Tenofovir
Zidovudine
85
HAART - NRTI - side effects - abacavir
Skin rash
Hypersensitivity
SJS
86
HAART - NRTI - side effects - tenofovir
Renal toxicity
| Osteomalacia
87
HAART - NNRTI -definition
Non Nucleoside analogue Reverse Transcriptase Inhibitors
88
HAART - NNRTI - 2 examples
Nevirapine
| Efavirenz
89
HAART - NNRTI - Efavirenz side effects
CNS side effects
90
HAART - what are the newest class of drugs?
Integrase inhibitors
91
HAART - which class of drugs are only used when dealing with resistant HIV ?
Protease inhibitors
92
HAART - protease inhibitor - example
Atazanvir
93
Partner notification - partner referral
Affected patient themselves tells their partner of their diagnosis
94
Partner notification - provider referral
Doctor contacts the patients partner on behalf of the patient and asks them to come for an HIV test
95
Partner notification - If the patient's partner is also one of your patients but the patient doesn't want to let them know...what do you do?
You have a duty of care to tel the patients partner
96
Partner notification - If the patient's partner is not one of your patients and the patient doesn't want to let them know...what do you do?
You have NO duty of care to them and your duty is to support your patient
97
Partner notification is needed for genital warts - true or false?
False
98
Partner notification is not needed for herpes. True or false?
True
99
If +ve HIV person is on HAART, what is the risk of transmission to their partner at that time?
0 (no risk)
100
You are more likely to transmit HIV if you have an STI. True or false?
True
101
Post exposure prophylaxis
Medication taken after exposure to reduce risk of infection.
| Start 3 anti-retrovirals within 72 hours of exposure
102
How long should you take post exposure prophylaxis ?
28 days
103
Pre-exposure prophylaxis
Medication taken before exposure to reduce the risk of infection.
-ve partner takes a daily pill that prevents HIV in that person
104
How long should -ve partner take pre exposure prophylaxis for ?
Take until +ve partner viral load becomes undetectable
105
Prevention of vertical transmission
HAART during pregnancy
106
Can +ve HIV female have a vaginal delivery?
Vaginal delivery acceptable if viral load is undetectable at 36 weeks
107
HIV +ve female must have a cesarean section. True or false?
False
| - Caesarean section required if viral load is not undetectable at 36 weeks gestation
108
If mother has detectable viral load, what does baby need?
Needs post exposure prophylaxis for 4 weeks
109
HIV +ve females must not breastfeed. True or false?
True
| - there is risk of transmission in breast milk so exclusive formula feeding required.
110
HIV is a single/double stranded DNA/RNA virus
Single stranded RNA virus
111
Risk of opportunistic infection occurs when the CD4 count is less than
200
112
How is the diagnosis of pneumocystic jirovecii made
BAL
113
What condition can JC virus resemble?
MS
114
Which organism causes Kaposi's sarcoma?
Human herpes virus 8
