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1
Q

What can HIV cause/lead to?

A

AIDS - Acquired Immunodeficiency Syndrome
Opportunistic infections
AIDS-related cancers

2
Q

What is the life expectancy of people with HIV?

A

“near normal”

3
Q

What is HIV?

A

A retrovirus

4
Q

Describe HIV-1

A

Originated in Central/West African chimpanzees

Responsible for pandemic starting in 1981

5
Q

Describe HIV-2

A

Originated in West African Sootey mangabey (Simian ID virus)

Less virulent

6
Q

What is CD4?

A

CD4+ receptors are the target site for HIV

A glycoprotein found on the surface of a range of cells

7
Q

What cells are CD4 receptors found on?

A

T helperlymohocytes (CD4+ cells)
Dendritic cells
Macrophages
Microglial cells

8
Q

What do CD4+ Th lymphocytes do?

A

Essential for induction of adaptive immune response
Recognition of MHC2 antigen-presenting cell
Activation of B-cells
Activation of cytotoxic T-cells (CD8+)
Cytokine release

9
Q

What does HIV do to the immune response?

A

Reduced circulating and proliferating of CD4 cells
Dysregulation expression of cytokines
Increased susceptibility to viral infections
Reduced affinity of antibodies produced

10
Q

What are HIV sufferers susceptible to?

A

Viral infections
Fungal infections
Mycobacterial infections
Infection-inducing cancers

11
Q

What is the normal range of CD4+Th cells?

A

500-1600 cells/mm*3

12
Q

What number of CD4+Th cells give risk to opportunistic infections?

A

<200 cells/mm*3

13
Q

Describe HIV viral replication?

A

Rapid replication in early and late infection

New generation every 6-12 hours

14
Q

What is the prognosis of HIV without treatment (on average)?

A

9-11 years

15
Q

How does the infection take place?

A

Infection of mucosal CD4 cell (Langerhans and Dendritic cells
Transport to regional lymph nodes
Infection established within 3 days of entry
Dissemination of virus

16
Q

How long after infection does it take for symptoms to present?

A

Usually 2-4 weeks

17
Q

What are the symptoms of a primary HIV infection?

A
Fever
Rash (maculopapular)
Myalgia
Pharyngitis
Headache/ aseptic meningitis
18
Q

What occurs in asymptomatic HIV infection?

A

Ongoing viral replication
Ongoing CD4 count depletion
Ongoing immune activation
Risk of transmission

19
Q

What is the definition of an Opportunistic infection?

A

An infection caused by a pathogen that does not normally produce disease in a healthy individual. But does when afforded the opportunity by a weakened immune system.

20
Q

What organism causes Pneumocystis pneumonia and what CD4 count is needed for this?

A

Organism - Pneumocystis jiroveci

CD4 count: <200

21
Q

What are symptoms and signs of Pneumocystis pneumonia

A

Symptoms: insidious onset, SOB, dry cough
Signs: Exercise desaturation

22
Q

How do you diagnose Pneumocystis pneumonia?

A

BAL and immunoflourescence +/- PCR

23
Q

What is the treatment and prophylaxis for Pneumocystis pneumonia?

A

Treatment: High dose co-trimoxazole (+/- steroid)
Prophylaxis: Low dose co-trimoxazole

24
Q

What other opportunistic infection that effects the respiratory system can occur in HIV?

A

TB

25
Q

What organism causes Cerebral Toxoplasmosis and what CD4 level is needed?

A

Organism: Toxoplasma gondii

CD4 level: <150

26
Q

What is cerebral toxoplasmosis?

A

reactivation of latent infection

Multiple cerebral abscess (Chorioretinitis)

27
Q

What are symptoms/signs of cerebral toxoplasmosis?

A
Headache
Fever
Focal neurology
Seizures
Reduced conscioussness
Raised ICP
28
Q

What organism causes Cytomegalovirus and what CD4 count is needed?

A

Organism: CMV

CD4 level: <50

29
Q

What is CMV?

A

Reactivation of latent infection.

30
Q

What are causes of CMV?

A

Retinitis
Colitis
Oesophagitis

31
Q

How does CMV present?

A

Reduced visual acuity
Floaters
Abdo pain, diarrhoea, PR bleeding

32
Q

When is screening for CMV done?

A

Individuals with a CD4 level of <50

33
Q

What skin infections can occur with HIV?

A
Herpes zoster
Herpes simplex
HPV
Penicilliosis
Histoplasmosis
34
Q

What is HIV-associated neurocognitive impairment?

A

Caused by HIV-1

Any reduced CD4 level

35
Q

How does HIV-associated neurocognitive impairment present?

A

Reduced short term memory

+/- motor dysfunction

36
Q

What is Progressive multifocal leukoencephalopathy?

A

Caused by JC virus

CD4 level of <100

37
Q

How does Progressive multifocal leukoencephalopathy present?

A

Rapidly progressing
Focal neurology
Confusion
Personality change

38
Q

List some other neurological presentations of HIV?

A
Distal sensory polyneuropathy
Mononeuritis multiplex
Vacuolar myelopathy
Aseptic meningitis
Guillan-Barre syndrome
Viral meningitis (CMV, HSV)
Cryptococcal meningitis
Neurosyphilis
39
Q

What causes kaposi’s Sarcoma and what is it?

A

Human Herpes virus 8 (HHV8)

Vascular tumour

40
Q

What CD4 level is needed for Kaposi’s sarcoma?

A

Any reduced level

41
Q

How does Kaposi’s sarcoma present?

A

Cutaneous
Mucosal
Visceral - pulmonary, GI

42
Q

How do you treat Kaposi’s sarcoma?

A

HAART
Local therapies
Systemic chemotherapy

43
Q

What organisms cause non-Hodgkins lymphoma and what CD4 level is needed?

A

EBV (Burkitt’s lymphoma), primary CNS lymphoma

Any reduced CD4 level

44
Q

What is the presentation of non-Hodgkins lymphoma?

A
More advanced
B symptoms
Bone marrow involvement
Extranodal diseaee
Increased CNS involvement
45
Q

What is the diagnosis and treatment of non-Hodgkins lymphoma?

A

Diagnosis - Same as HIV

Treatment: Same as HIV + HAART

46
Q

What organism causes Cervical cancer?

A

HPV

47
Q

What is cervical cancer?

A

Rapid progression to severe dysplasias and invasive disease

48
Q

Name some non-OI of symptomatic HIV

A
Mucosal candidiasis
Seborrhoeic dermatits
Fatigue + diarrhoea
Worsening psoriasis
Lympadenopathy
parotitis
49
Q

What causes haematologic manifestations?

A

HIV
OI’s
AIDS - malignancies
HIV drugs

50
Q

What are haematological manifestations of HIV?

A

Anaemia

Thrombocytopenia

51
Q

What CD4 level is needed for haematological manifestations to present?

A

Any reduced CD4 level

52
Q

What factors increase the risk of HIV transmission?

A

Anoreceotive sex
Trauma
Genital ulceration
Concurrent STI

53
Q

What ways can a mother pass HIV on to her child?

A

In utero/trans-placental
Delivery
Breast-feding

54
Q

What is the prevalence of HIV in the UK?

A

1.5/1000

55
Q

How many people are living with diagnosed HIV in Tayside?

A

366

56
Q

What markers of HIV are used in labs to detect infection?

A
RNA (viral genome)
Envelope proteins (gp120)
Capsule protein (p24)
57
Q

When were HIV antibody tests first introduced?

A

1985

58
Q

What is the window period for HIV antibody testing?

A

~63 days

59
Q

What antibodies are detected in 3rd generation HIV?

A

IgG and IgM

60
Q

What is the window period for 3rd generation HIV antibody testing?

A

~average of 20-25 days

61
Q

Describe 4th generation HIV tests

A

Combined antibody and antigen (p24)
Shortens window period by ~5 days (around 14-28 days)
Variability between assays and between labs

62
Q

What is POCT?

A

A rapid HIV test
results in 20-30 mins
3rd generation (ab only)
4th generation (ab/ag)

63
Q

What are the advantages of POCT?

A
Simple to use
No lab needed
No venepuncture needed
No anxious wait
Reduce follow up
Good sensitivity
64
Q

What are the disadvantages of POCT?

A
Expensive -£10
Quality control
Clinical governance
Poor +ve predictive value in low prevalence settings
Not suitable for high volume
Cant be relied on in early infection
65
Q

What does RITA stand for?

A

Recent Infection

Testing Algorithm

66
Q

Describe RITA?

A

Used to identify if an infection occured within the preceeding 4-6 months
Measure different types of antibodies or strength of antibody binding

67
Q

What are the advantages of RITA?

A
Surveillance
Local epidemiology
Assess HIV testing programmes
Inform partner notification
Safer sex advice
Interpretation of CD4
68
Q

What are the disadvantages of RITA?

A

Accuracy
Patient distress
Criminilisation