HIV

Question 1

Spread of HIV

Answer 1

Sexual transmission
Injection drug misuse
Blood products
Vertical transmission
Organ transplant

Question 2

Point of Care HIV test

Answer 2

Blood sample from finger

60sec test

Standard test will confirm results

Question 3

Immunology of HIV

Answer 3

Infects and destroys cells of the immune system especially T-helper cells that are CD4

CD4 receptors are not exclusive to lymphocytes - also present on surface of macrophages and monocytes

Question 4

Natural history of HIV

Answer 4

Over course of infection;

CD4 count declines and HIV viral load increases

Increased risk of developing infections and tumours

Severity of these illnesses is greater the lower the CD4 count

Most AIDS diagnoses occur at CD4 count <200

Acute infection - seroconversion, asymptomatic, HIV related illness, AIDS defining illness, death

Question 5

HIV classification

Answer 5

Original classification was clinical

Clinical stage I-IV

Question 6

HIV Clinical Stage 1

Answer 6

Asymptomatic
Persistent generalised lymphadenopathy

Performance scale 1; asymptomatic, normal activity

Question 7

HIV Clinical Stage 2

Answer 7

• Weight loss <10% of body weight
• Minor mucocutaneous manifestations
• Herpes zoster within last 5 yrs
• Recurrent URTIs

and/or performance scale 2; symptomatic, normal activity

Question 8

HIV Clinical Stage 3

Answer 8

• Weight loss >10% body weight
• unexplained chronic diarrhoea >1 month
• Unexplained prolonged fever >1month
• Oral candidiasis
• Oral hairy leukoplakia
• Pulmonary TB within past year
• Severe bacterial infections

and/or performance scale 3; bedridden, <50% of day during last month

Question 9

HIV Clinical Stage 4

Answer 9

• Pneumocytic carinii pneumonia
• toxoplasmosis of brain
• cryptosporidiosis with diarrhoea >1month
• cryptococcus extrapulmonary
• cytomegalovirus
• HSV
• progressive multifocal leukoencephalopathy
• candidiasis of oesophagus, trachea, bronhchi, lungs
• atypical mycobacteriosis

and/or performance scale 4 ; bedridden, <50% day last month

Question 10

AIDS defining respiratory conditions

Answer 10

Tuberculosis

Pneumocystitis

Question 11

AIDS defining neurology conditions

Answer 11

• Cerebral Toxoplasmosis
• Primary cerebral lymphoma
• Cryptococcal meningitis
• Progressive multifocal leucoencephalopathy

Question 12

AIDS defining dermatology conditions

Answer 12

Kaposi’s sarcoma

Question 13

AIDS defining oncology conditions

Answer 13

Non-Hodgkin’s lymphoma

Question 14

AIDS defining gynaecology conditions

Answer 14

Cervical cancer

Question 15

AIDS defining opthalmology conditions

Answer 15

Cytomegalovirus retinitis

Question 16

What is HIV/seroconversion?

Answer 16

A seroconversion illness is when HIV antibodies first develop

Abrupt onset 2-4weeks post-exposure, self-limiting 1-2weeks

Symptoms generally non-specific and differential diagnosis includes a range of common condition

Question 17

Describe symptoms of HIV seroconversion

Answer 17

Flu-like illness
Fever
Malaise and lethargy
Pharyngitis
Lymphadenopathy
Toxic exanthema 

“looks like glandular fever but EBV serology not in keeping”

Question 18

Describe pneumocystitis jiroveci pneumonia

Answer 18

Commonest late stage (AIDS) infection

Opportunistic infection

CD4 cell count usually <200

Classical history of dry cough and increasing breathlessness over several weeks

Treatment; cotrimoxazole, pentamidine

Question 19

Describe HIV antiretroviral therapy

Answer 19

Different classes of drugs acting on different stages in HIV lifecycle

Combination therapy is at least 3 drugs from at least 2 groups

Adherence needs to be >90%

cART can lead to normal life but side effects can be significant eg metabolic, lipodystrophy

Question 20

Where do HIV treatments work?

Answer 20

Binding and entry

Reverse transcription

Integration

Transcription

Assembly

Release and Protease

Question 21

When to start HIV patients on medication?

Answer 21

All patients at diagnosis regardless of CD4 and viral load

If CD4 < 350 cells/mm3 patients at risk of developing symptoms without being on treatment

If CD4 < 200 start asap

Any pregnant woman - start before third trimester

Three drug combo w/ treatment adjustment if viral load not adequately suppressed after 4-6weeks

Question 22

Current HIV life expectancy

Answer 22

Life expectancy according to CD4 nadir (lowest before starting therapy)

<100 = 52
100-200 = 62
>200 = 70+

Question 23

Describe nucleoside reverse transcriptase inhibitors

Answer 23

HIV antiviral

Side effects include marrow toxicity, neuropathy, lipodystrophy

Question 24

Describe non-nucleoside reverse transcriptase inhibitors

Answer 24

HIV antiviral

Side effects include skin rashes, hypersensitivity, drug interactions, neuropsychiatric effects

Question 25

Describe protease inhibitors

Answer 25

HIV antiviral Drug interactions, diarrhoea, lipodystrophy and hyperlipidaemia

Question 26

Describe integrase inhibitors

Answer 26

HIV antiviral Side effects include rashes and disturbed sleep

Question 27

What to do if a patient develops lipodystrophy?

Answer 27

Change drugs Less likely to happen with newer agents Cosmetic procedures - facelift - liposuction - fillers

Question 28

Describe HIV prevention

Answer 28

Behaviour change and condoms Circumcision Treatment as prevention Pre-exposure prophylaxis (PrEP) Post- exposure prophylaxis for sexual exposure

Question 29

Describe the virology of HIV

Answer 29

Two types; 1 and 2 4 groups - HIV-1-M responsible for epidemic - N, O and P uncommon Within N group there are 9 subtypes; ABCDFGHJK HIV is a lentivirus (belongs to retrovirus group) - cause slow infections with long incubation - RNA to DNA using reverse transcriptase

Question 30

HIV tests

Answer 30

``` Antibody (during first month tests may be negative) Antigen Then; - viral load - CD4 count - typing - avidity - tropism - resistance tests - drug levels ```

Question 31

Describe HIV resistance testing

Answer 31

Sequencing of the polymerase and protease genes Identification of specific mutations that confer resistance to antiviral drugs Used for - baseline at diagnosis - suboptimal treatment response - treatment failing - want to change treatment for another reason

Question 32

Body fluids to be handled with the same precautions as blood

Answer 32

``` CSF Pleura, peritoneal, pericardial fluid Breast milk Amniotic fluid Vaginal secretions/semen Synovial fluid Any other body fluid w/visible blood Unfixed tissues and organs Saliva - dental procedures Exudate/tissue fluid from burns or skin lesions ```

Question 33

What to do after body fluid exposure risk?

Answer 33

Wash off splashes on skin with soap and running water Exposed mucous membranes including conjunctivae should be irrigated copiously with water Encourage bleeding if broken skin Wash out splashes in eye, nose, mouth Involve Occupational Health Send BBV screen for storage

Question 34

Describe HIV post-exposure prophylaxis

Answer 34

if high risk blood/body fluid Commence within 72hours of exposure Complete 28day course HIV test 2 months after PEP