HIV - testing and clinical management

Question 1

Why is diagnosis important?

Answer 1

15% undiagnosed in UK
Missed opportunities in healthcare
If diagnosed late
-more likely to die (10x more likely to die in the first year)
-transmission to others

Question 2

Breaking down stereotypes

Answer 2

60. 2% white
61. 2% black African
62. 1% sex between men
63. 1% heterosexual

Question 3

HIV in Yorkshire

Answer 3

Sheffield >1.1 in 1000
-Leeds >2 in 1000
More late diagnoses than national average

Question 4

Clinicator indicator diseases for adult HIV infection - head and neck

Answer 4

Kaposi's sarcoma 
-severe realcitrant seborrhoeic dermatitis
-multidermatomal or recurrent herpes zoster
Persistent cryptosporidosis
-oral candidiasis
-oral hairy leukoplakia
Non-Hodgkin's lymphoma
-head and neck cancer
-Hodgkin's lymphoma
-Castleman's disease
Lymphadenopathy of unknown cause
Chronic parotitis
Lymphoepithelial parotid cysts
***

Question 5

Candidiasis

Answer 5

Fungal infection
Unusual in healthy adults
84-100% of PLWH affected

Question 6

Shingles

Answer 6

Reactivation of Varicella Zoster Virus
Dermatomal distribution
Painful blistering rash, malaise

Question 7

Risk factors for shingles

Answer 7

Age

Immunocompromised

Question 8

Risk factors for candidiasis

Answer 8

Age

Immunocompromised

Question 9

How do we test?

Answer 9

Verbal consent (and document)
If he said no
-why
-incorrect beliefs re virus/ testing
Send clotted blood to lab
4th generation test
-antibody/ antigen
-window period 1 month
-costs 99.9% positive predictive values
-sensitive screening, secific confirmatory

Question 10

Sensitivity

Answer 10

Percentage of pts with the disease that receive a positive test result
True positives / (true positives + false negatives)

Question 11

Specificity

Answer 11

Percentage of pts without the disease that receive a negative test result
True negatives / (true negatives + false positives)

Question 12

What to do after testing?

Answer 12

Call specialist for advice
-infectious diseases/ sexual health/ HIV specialist nurse
Result
-given face to face
-confidential environment
Contact tracing etc. done by specialist services

Question 13

Other ways to test

Answer 13

"Point of care" tests
-finger prick
-mouth swab
-saliva
Antibody only tests
Antigen only tests
HIV RNA PCR - "viral load"

Question 14

Kaposi’s sarcoma

Answer 14

Human Herpesvirus - 8
Usually linked with HIV
Spindle cells on biopsy
Needs referral to oncology
If not known HIV needs to test!

Question 15

Oral hairy leukoplakia

Answer 15

Epstein-Barr virus
White patches, can’t be scraped off
-usually on sides of tongue
Linked with HIV, smoking and immunosuppression

Question 16

Herpes Simplex Virus (HSV)

Answer 16

"Coldsores"
HSV1/ HSV2
In HIV
-more frequent
-more severe
-outbreaks last longer
-may also have genital herpes

Question 17

HAART

Answer 17

3+ antiretroviral drugs
-act on different points in HIV replication cycle to suppress the virus
-fusion/ entry inhibitors
-reverse transcriptase inhibitors
-integrase inhibitors
-protease inhibitors
No cure yet

Question 18

Why HIV becomes resistant to drugs

Answer 18

1 mutation in every 2 new viruses produced
1 - 10 billion new virus particles each day
1-5 billion mutations per day
Triple therapy - only 1 in 1 trillion chance of resistant mutations

Question 19

Therapeutic drug levels essential to keep HIV suppressed

Answer 19

1. Non-adherence: missing one or two doses can cause resistance
   - HIV can copy itself
2. Drug-drug interactions
   - many drugs interact with antiretrovirals, therefore can cause subtherapeutic levels
   - e.g. do not coadminister nevirapine, itraconazole

Question 20

Sources of information about drug interactions

Answer 20

HIV drug interactions - Uni of Liverpool
Pharmacy
Local HIV services
Drug info sheets