HIV/AIDS Flashcards
How is HIV transmitted?
Sexual transmission Injection drug misuse Blood products Vertical transmission Organ transplant Needlestick injury/sharing needles
When can you test an unconscious patient for HIV?
When you think it is in the patient’s interest to have the test
What is the POC testing for HIV?
Blood sample from individual’s finger
How long does the POC testing for HIV take?
60 seconds
How does HIV infection affect the immune system?
HIV infects and destroys cells of the immune system especially the T-helper cells that are CD4+
What cells in particular dos HIV infect and destroy?
T-helper cells that are CD4+
Where are CD4+ receptors present?
Lymphocytes, surface of macrophages and monocytes, cells in the brain, skin and other sites
What happens to the CD4+ count over the course of the HIV infection ?
CD4+ count declines
HIV viral load increases
What is there an increased risk of as HIV infection develops?
Developing infections and tumours
What is normal CD4+?
> 500
As the severity of the illnesses caused by HIV increases what happens to the CD4 count?
Lower the CD4+ count
At what CD4+ count do most AIDS diagnoses occur?
CD4+ count <200
What increases as CD4+ count decreases?
HIV RNA
How many clinical stages of HIV are there?
4 stages
What are the symptoms of HIV at Clinical Stage I?
Asymptomatic
Persistant generalised lymphadenopathy (PGL)
What are the symptoms of HIV at Clinical Stage II?
Weight loss (<10% of body weight)
Minor mucocutanous manifestations
Herpes zoster within last 5 years
Recurrent URTI
What are examples of minor mucocutaneous manifestations of HIV at Clinical Stage II?
Seborrheic dermatitis, prurigo, fungal nail infections, recurrent oral ulcerations, angular chelitis
What are the symptoms of HIV at Clinical Stage III?
Weight loss (>10% of body weight) Unexplained chronic diarrhoea >1 month Unexplained prolonged fever >1 month Oral candidiasis Oral hairy leukoplakia Pulmonary TB within past year Severe bacterial infections
What are the symptoms of HIV at Clinical Stage IV?
HIV wasting syndrome Pneumocystic pneumonia Toxoplasmosis of brain Cryptosporidiosis with diarrhoea >1mo Cytomegalovirus (MCV) disease of an organ other than liver, spleen or lymph nodes HSV infection Progressive multifocal leukoenephalopathy (PML) Candidiasis (widespread) HIV encephalopathy Atypical mycobacteriosis Extrapulmonary TB
How else can HIV be assessed other than Clincal stages?
Performance scale
What are the 4 performance scales for HIV?
Performance scale 1: asymptomatic, normal activity
Performance scale 2: symptomatic, normal activity
Performance scale 3: bedridden, <50% of the day during last month
Performance scale 4: bedridden, >50% of the day during the last month
What is the difference between HIV and AIDS?
HIV infection = no symptoms
AIDS = weakness in immune system causing infections and tumours to develop
What is the natural history of HIV/AIDS?
Acute infection - seroconversation -> asymptomatic -> HIV related illnesses -> AIDS defining illness -> death
What percentage of patients have a seroconversion illness (when HIV antibodies first develop)?
30-60% of patients
How long post-exposure is the onset of a seroconversion illness?
2-4wks
How long does a seroconversion illness usually last?
1-2wks (self-limiting)
What are the symptoms for a seroconversion illness?
Flu-like illness Fever Malaise and lethargy Pharyngitis Lymphadenopathy Toxic exanthema
What does a seroconversion illness often look like?
Glandular fever
What is seroconversion illness?
After a person contracts HIV, their immune system begins to develop HIV antibodies. Seroconversion is the period during which these antibodies first become detectable.
What is the commonest late stage (AIDS) infection?
Pneumocystis jiroveci pneumonia
What is the CD4 cell count normally in pneumocystis jiroveci pneumonia?
<200
What is the classical history for pneumocystis jiroveci pneumonia?
Dry cough
Increasing breathlessness over several weeks
What are the investigations for pneumocystis jiroveci pneumonia?
CXR
Induced sputum or bronchoscopy for PCR
What is the treatment for pneumocystis jiroveci pneumonia?
Cotrimoxazole
Pentamidine
Prophylaxis until CD4 >200
What is ART?
Antiretroviral treatment
What is combination ART?
At least 3 drugs from at least 2 groups of HIV class drugs
What does adherence to ART have to be to support the patient?
90%
What are the different types of inhibitors (ARTs)?
Reverse transcription inhibitors
Integrase inhibitors
Protease inhibitors
When should you start patients on ARTs?
At diagnosis, regardless of CD4 and viral load
With what CD4 count are patients at risk of developing symptoms if they are not on treatment?
<350
When should ART be started with pregnant women?
Start before third trimester
What is the treatment if viral load not adequately suppressed after 4-6wks?
Three drug combination with treatment adjustment - if viral load not adequately suppressed after 4-6wks
What does a CD4 nadir mean?
The lowest CD4 cell count recorded
How long is the treatment for HIV?
Life-long
Why might HIV treatment fail?
Incomplete suppression: inadequate potency, inadequate drug levels, inadequate adherence, pre-existing resistance
What are side effects of NUCLEOSIDE reverse transcriptase inhibitors?
Marrow toxicity
Neuropathy
Lipodystrophy
What are side effects of NON-NUCLEOSIDE reverse transcriptase inhibitors?
Skin rashes
Hypersensitivity
Drug interactions
Neuropyschiatric effects
What are side effects of protease inhibitors?
Drug interactions
Diarrhoea
Lipodstrophy
Hyperlipidaemia
What are side effects of integrase inhibitors?
Rashes
Disturbed sleep
What is lipodystrophy?
Abnormal distribution of fat in the body
What are ways of HIV prevention?
Behaviour change/condoms Circumcision Treatment as prevention Pre-exposure prophylaxis (PrEP) Post-exposure prophylaxis for sexual exposure (PEPSE)
What is the most common type of HIV?
HIV-1
What is the HIV group responsible for the epidemic?
HIV-1-M
What type of virus is HIV?
Lentivirus (retrovirus)
What drugs are for post-exposure prophylaxis?
Truvada and Raltegravir
How long should Truvada and Raltegravir be taken as PEP?
28 days
How long after exposure should PEP be started?
Within 72hrs
