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Flashcards in HIV: Pathophysiology Deck (33)
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1
Q

What type of virus is HIV and where did it originate

A

retrovirus
HIV 2- west African Sooty mangabey
HIV 1- central/west African chimpanzees

2
Q

What immune cell is the target site for HIV

A

CD4 receptors found on immune cells particularly T helper cells, dendritic cells, macrophages and microglial cells

3
Q

What effect does HIV have on the immune response

A
reduced circulating CD4 cells
Reduced proliferation of cd4 cells
reduced CD8 cell activation
reduction in antibody class switching
CHRONIC IMMUNE ACTIVATION
4
Q

What are people with HIV more susceptible yo

A

viral infections
fungal infections
mycobacterial infections
infection induced cancer

5
Q

what are the normal cd4 parameters

A

500-1600 cells/mm3

6
Q

at what CD4 count is someone at risk of opportunistic infections

A

less than 200

7
Q

what are the main phases of HIV infection

A

primary infection
asymptomatic infection
symptoms of AIDS

8
Q

what is the average time between infection and death without treatment

A

9-11 yrs

9
Q

what are the features of primary hiv infection

A

usually onsets 2-4 weeks after infection
flu like illness- rash, fever, myalgia, pharyngitis etc
high risk of transmission at this point

10
Q

what are the features of asymptomatic infection

A

ongoing viral replication
ongoing cd4 count depletion
ongoing immune activation
risk of onward transmission of undiagnosed

11
Q

what is an opportunistic infection

A

an infection caused by a pathogen that does not normally produce disease in a healthy indicidual

12
Q

which organism causes pneumonia often in patients with HIV

A

pneumocystis jiroveci

13
Q

what is the treatment of pneumocystis pneumonia

A

high does co-trimoxazole (give low dose for prophylaxis)

+/- steroid

14
Q

What is cerebral toxoplasmosis

A

a parasitic infection resulting in multiple cerebral abscesses causing headache, fever, focal neurology, seizures, reduced consciousness and raised intracranial pressure

15
Q

at what cd4 count can toxoplasmosis infection occur

A

less than 150

16
Q

at what CD4 count can you get cytomegalovirus

A

less than 50

17
Q

how can CMV present

A

preduced visuall acuity
floaters
abdo pain, PR bleeding

18
Q

what skin infectiosn are common in HIV

A
herpes zoster
herpes simplex
HPV
pencilliosis
Histoplasmosis
19
Q

what virus causes HIV associated neurocognatice impairement

A

HIV 1

20
Q

what organism causes Progressive multifocal leukoencephelopathy and at what CD4 threshold

A

JC virus

less than 100

21
Q

Name some AIDS related cancers

A

Kaposi’s sarcoma (vascular tumour)
Non hodgkins lymphoma
cervical cancer

22
Q

what virus causes kaposi’s

A

human herpes virus 8

23
Q

what organism can cause non hodgkins

A

EBV

24
Q

what kind of things may a patient with symptomatic HIV present with

A
mucosal candidiasis
seborrhoeic dermatitis
diarrhoea
fatigue
psoriasis
lymphadenopathy
parotitis
STIs, hep B or C
25
Q

what haematological conditions occur in those with HIV

A

anaemia

thrombocytopenia

26
Q

how is HIV most commonly transmitted

A

sexual
51 percent (MSM)
49 percent between men and woman

27
Q

what factors increase transmission risk

A

anoreceptive risk
trauma
genital ulceration
concurrent STI

28
Q

name another mode of transmission

A
parenteral=
IVDU
infected blood products
iatrogenic
mother to child=
in utero
delivery
breast feeding
29
Q

which group of people are most likely to present late with HIV

A

heterosexual men

30
Q

how many people in the UK living with HIV are undiagnosed

A

1/4

31
Q

when is universal (opt out) testing implimented

A

in high prevelance areas in the uK ie HIV rate is locally more than 0.2 percent of population

32
Q

where is and opt out HIV test always offered in the UK

A
TOP services
GUM clinic
drug dependency services
antenatal services
assisted conception
33
Q

what groups of people are deemed high risk and should be offered screening

A
MSM
female partners of bisexual men
IVDU
partners of people with HIV
adults/children/sexual partners from endemic areas
history of iatrogenic exposure