HIV TESTING Flashcards
What proportion of people with HIV in the UK remain undiagnosed?
About a quarter
What proportion of people with HIV are diagnosed very late, when there CD4 count is below 200 cells/microlitre?
30% (as of 2012)
What groups of patient are more likely to be diagnosed later on in the disease progression?
Older age groups
Heterosexual men
Black and ethnic minority groups
When were new guidelines on HIV testing brought out in the UK?
UK National Guidelines for HIV Testing 2008
Which groups did 2011 NICE guidelines regarding HIV testing target?
Black African communities
Men who have sex with men
Is HIV testing done on an opt-in or opt-out basis?
Opt-out
What are the specific settings where HIV testing should be routine?
GUM/Sexual Health Clinics
Antenatal services
Termination of pregnancy services
Drug dependency programmes
Healthcare services for those diagnosed with an AIDS defining condition (esp TB, hep B, hep C and lymphoma)
What is the prevalence of HIV in women undergoing termination?
Up to 1%
At what prevalence does it become cost effective to test all patients for HIV?
In any area where prevalence is equal to or more than 2 in 1000 among 15 to 59 year olds
At what prevalence does it become cost effective to test patients with a certain symptom or condition for HIV?
With any symptom or condition where the prevalence of HIV is equal or more than 1 in 1000
What proportion of people with TB have HIV?
Over 5%
Which groups of symptom-less people should routinely be offered HIV test?
Patients diagnosed with STI
Sexual partners of individuals known to be HIV positive
Men who have had sexual contact with men
Female sexual contacts of men who have sex with men
Individuals who have ever injected drugs
Men and women from countries where prevalence of HIV is more than 1%
Men and women who have had sexual contact abroad or in the UK with individuals from countries where prevalence of HIV is more than 1%
Blood donors
Organ transplant donors
What are the respiratory AIDS defining conditions?
Tuberculosis
Pneumocystis
What are the other respiratory conditions that are not necessarily AIDS defining but that are associated enough with HIV that sufferers should be tested?
Bacterial pneumonia
Aspergillosis
What are the neurological AIDS defining conditions?
Cerebral toxoplasmosis
Primary cerebral lymphoma
Cryptococcal meningitis
Progressive multifocal leucoencephalopathy
What are the other neurological conditions that are not necessarily AIDS defining but that are associated enough with HIV that sufferers should be tested?
Aseptic meningitis/encephalitis Space occupying lesion of unknown cause Guillain-Barre syndrome Transverse myelitis Peripheral neuropathy Dementia Leucoencephalopathy
What are the dermatological AIDS defining conditions?
Kaposi sarcoma
What are the other dermatological conditions that are not necessarily AIDS defining but that are associated enough with HIV that sufferers should be tested?
Severe or recalcitrant seborrhoeic dermatitis
Severe or recalcitrant psoriasis, multidermatomal or recurrent herpes zoster
What are the gastrointestinal AIDS defining conditions?
Persistent cryptosporidiosis
What are the other oral and gastrointestinal conditions that are not necessarily AIDS defining but that are associated enough with HIV that sufferers should be tested?
Oral candidiasis Oral hairy cell leucoplakia Chronic diarrhoea of unknown cause Weight loss of unknown cause Salmonella, shigella or campylobacter Hepatitis B infection Hepatitis C infecion
What are the oncological AIDS defining conditions?
Non-Hodgkin’s lymphoma
Cervical cancer
What are the other oncological conditions that are not necessarily AIDS defining but that are associated enough with HIV that sufferers should be tested?
Anal cancer or anal intraepithelial dysplasia
Lung cancer
Seminoma
Head and neck cancer - associated with HPV
Hodgkin’s lymphoma
Castleman’s disease (giant lymph nodes - lymphoproliferative disorder)
What are the gynaecological AIDS defining conditions?
Cervical cancer - associated with HPV
What are the other gynaecological conditions that are not necessarily AIDS defining but that are associated enough with HIV that sufferers should be tested?
Vaginal intraepithelial neoplasia
Cervical intraepithelial neoplasia Grade 2 or above
What are the haematological AIDS defining conditions?
Non-Hodgkin’s lymphomas
What are the other haematological conditions that are not necessarily AIDS defining but that are associated enough with HIV that sufferers should be tested?
Any explained blood dyscrasia including:
Neutropenia
Thromboytopenia
Lymphopenia
What are the ophthalmological AIDS defining conditions?
Cytomegalovirus retinitis
What are the other ophthalmological conditions that are not necessarily AIDS defining but that are associated enough with HIV that sufferers should be tested?
Infective retinal disease including herpes viruses and toxoplasma
Any unexplained retinopathy
What are the ENT conditions that are not necessarily AIDS defining but that are associated enough with HIV that sufferers should be tested?
Lymphadenopathy of unknown cause
Chronic parotitis
Lymphoepithelial parotid cysts
What are the non specific conditions which are associated enough with HIV that sufferers should be tested?
Pyrexia of unknown cause
Any lymphadenopathy of unknown cause
Mononucleosis-like syndrome (primary HIV infection)
Any sexually transmitted infection
What are different things we can look for when diagnosing HIV?
Antibodies
Antigen - p24
Viral load
What are the different types of test?
Lab-based blood tests
Rapid point of care tests
What is the recommended first-line screening test for HIV infection?
Laboratory assay that tests for HIV antibody and p24 antigen simultaneously - 4th generation
What do third generation HIV tests look for?
They detect IgM, IgG and IgA antibodies against HIV.
What is the window period for third generation HIV tests?
3 months. Basically the point where the person will start making antibodies which is on average 25 days, but 97% of people will have made antibodies by 3 months so we say the window period is 3 months.
What do fourth generation HIV tests look for?
HIV antibodies and p24 antigens
What is the window period for fourth generation HIV tests?
2 to 4 weeks. This is dependent on the point where p24 antigen starts being made in large enough amounts to be detected.
What are the advantages of using a rapid point of care test over a lab test?
Fast - result in 30 minutes
Simple equipment
Easy to perform and interpret
Include a control
What are the disadvantages of using a rapid point of care test versus a lab test?
Expensive
Reduced sensitivity in early infection
Prone to operator errors
May give false positive result
Positive results require lab tests anyway
Does having a routine HIV test in itself affect future life insurance?
No, not since 1994
