HIV Flashcards
What does it stand for?
Human Immunodeficiency Virus
Pathophysiology:
How is it transmitted? - 4 ways
What type of T cells does it attach to?
What other WBC does it also attach to, so therefore affects?
Where do these type of T cells migrate to?
Read the rest for the viral pathophysiology!!!!!!!!!!!!
Sex (including oral)
IV drug use
Blood transfusions
Vertically - mother to foetus
CD4 T cells (T helper cells) + Macrophages (+ dendritic cells as it has CD4 on its surface)
Integrates into DNA and moves to lymph nodes
Billions of virions are produced at the lymph nodes which further infect new CD4 cells
As the infection progresses, the depletion or impaired function fo CD4 cells lead to reduced immune function.
Why is HIV so difficult to manage?
It is a retrovirus
This means it encodes reverse transcriptase allowing DNA copies to be produced from viral RNA
This is error-prone
Significant mutation rate
Therefore there can be multiple different versions of the virus within one patient so it can be hard to clear the infection.
What is measured which will dictate the severity of the disease?
CD4 count
AIDS:
What does it stand for?
A patient must have a low CD4 count and an AIDs defining illness. Under what CD4 count is classed as AIDS?
AIDS is rarely seen in practice today due to better Rx or due to the word being avoided due to stigma.
END STAGE HIV CAN BE USED INSTEAD.
Acquired immunodeficiency syndrome
CD4<200
Time course of infection:
What happens in the first 1-6 wks post-infection?
After this, the immune system mounts a response. What may patients notice?
How many yrs after the initial infection will the person begin to get the multisystem manifestations of HIV?
What is this called?
Seroconversion illness - similar to infectious mononucleosis
Generalised lymphadenopathy
10 yrs
Clinical latency
S+S:
Seroconversion illness:
- What may they notice is swollen?
- What may they notice on their skin?
- What happens in the pharynx?
- What systemic symptoms do they have? - 2
- Where do they get pain? - 2
- How long does this last?
What may persist for >3 months after initial infection? - it is one of the above
Lymph nodes - lymphadenopathy
Maculopapular/erythematous rash
Pharyngitis
Malaise
Fever
Myalgia
Headache
1-2 wks
OFFER HIV TEST TO ALL THOSE WITH FLU LIKE SYMPTOMS AND A RASH
Generalised lymphadenopathy
Presentation by the system:
REMEMBER MOST ARE DUE TO OPPORTUNISTIC INF.
Respiratory:
- A fungal infection called PCP may occur. What does it stand for?
- What symptoms do they get?
- What happens on exertion?
- What is seen on CXR in the hilar region?
Other fungi can affect the lungs!
What bacterial infections can occur?
Pneumocystis pneumonia
Dry cough
SOB
Desaturation on exertion
Perihilar infiltrates
TB
CMV
Strep/staph pneumonia
Presentation by the system:
Neurological:
- Toxoplasma encephalitis - what does this cause?
- Cryptococcal MENINGITIS - what type of pathogen is this?
- What type of cancer is there an increased risk of?
- What neurological disease can develop if treatment is not started before then?
- HIV can also cause peripheral neuropathy. How does this present?
Neurological signs
Seizures
Intracranial abscesses
Toxoplasma is a parasite!!!!!!
Fungus/yeast- it causes chronic meningitis
Lymphoma - Primary cerebral lymphoma
Dementia:
Before cART some people with HIV would go on to develop dementia, but this is now uncommon. However, many people who have HIV still experience a milder type of cognitive impairment, such as problems with their memory and thinking. This is called HIV-associated neurocognitive disorder (HAND).
A slight tingling or burning sensation
Presentation by the system:
Skin:
Due to HIV, KAPOSI SARCOMA can develop.
- What virus causes this?
- What does it produce on the skin?
- Where?
Mouth:
- What do they get?
- EBV causes non-cancerous white growths on the lateral tongue. What is this called?
Human Herpesvirus 8
Purple papules
Face, mouth, back, lower limbs, genitalia
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Oral and oesophageal candidiasis
Oral hairy leukoplakia
Presentation by the system:
GI:
- What does cryptosporidiosis protozoa cause? - 1
- What virus causes colitis and oesophagitis?
- They also get unexplained weight loss. What is this called?
They can also get a range of different GI infections!!!!
Cancer:
- What type of lymphoma can arise?
- What 2 cancers are linked to HPV - the HPV is not dealt with as it should so it is free to grow
They can also get head and neck cancers as well as lung cancer.
Eye:
- What part of the eye becomes inflamed due to CMV?
Chronic diarrhoea
CMV
HIV wasting syndrome
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B-cell lymphoma - EBV related
Cervical and anal cancers
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CMV retinitis:
- Blurred vision
Investigations:
Who should be tested? - 3
Screening Tests:
- It is sometimes called a combine test. What 2 things are tested for in serology?
- This can’t be used in in neonatal HIV as false positive can occur. Why and what is an alternative?
- What antibody-ONLY tests are there?
Serology - what do you test for?
Confirmatory tests:
- What is test is used?
- What 2 types of HIV does it test for?
Detection of viral RNA - indications?
Viral load instead
All patients with clinical features of acute or chronic HIV infection
High risk individuals
Early pregnancy
=========
Anti-HIV antibodies + p24 antigen (HIV antigen)
False-positive due to maternally transferred anti-HIV antibodies.
ELISA (enzyme-linked immunosorbent assay) - lab needed - 1-3 hrs
Rapid tests - 20 minute results ========== HIV-1/HIV-2 antibody differentiation immunoassay - can detect both types and distinguishes them both - allows tailoring of Rx ========== Neontal infection Inconclusive results Presenting before seroconversion - needle stick injury, notification Screening for transfusion
Management:
Lifestyle and preventative:
- What may they need counselling for?
- What vaccines should they have?
Name of standard drug treatment of HIV?
Counselling to prevent high-risk sexual behaviours
Assistance with partner notification and contact tracing
Hep A and B
Annual flu
Pneumococcal vaccine etc.
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Antiretroviral therapy
Management:
Antiretroviral therapy (ART):
- What does it do?
- What is CART?
There are 4 types and they might be used in combination.
Under what CD4+ count is ART indicated? - 3
What are other indications for ART? - 2
Treating co-infection:
- Why is treating active TB difficult in someone with HIV?
Prophylactic ABs:
- What AB is used to prevent PCP and toxoplasma abscesses?
There are a range of prevention of vertical transmission in pregnancy!!!!
Reduces the HIV viral load to a level of undetectability
Combination antiretroviral therapy
CD4 < 350 cells/mm3
High viral load
Presence of AIDS-defining illness
Due to drug interactions in TB and ART
Co-trimoxazole
ART Side effects:
What GI effects do they commonly cause? - 3
What may they notice on their skin? - this is a common reaction to a lot of meds
They may also get lipodystrophy. What is it?
SIDE EFFECTS VARY DEPENDING ON DRUGS!
D & V
Hepatitis
Rash
Fat reduction peripherally (head and limbs) but gain centrally
Prevention:
What will reduce transmission?
Serosorting can also be used. What is it?
PEP:
- What does it stand for?
- Indications? - 3
- How long after HIV exposure in sex are they given?
- It is a type of ART. What is the usual drug given?
- What drug name is used in the UK? - T
Continued testing 8-12 wks post-exposure
It is unreliable as it is inaccurate and someone might not disclose
Condoms - by 90%
Serosorting, also known as “serodiscrimination”, is the practice of using HIV status as a decision-making point in choosing sexual behaviour.
Post-exposure prophylaxis
Needle stick injury
Contamination of open wounds or mucous membranes with HIV
Sexual transmission from known or potential host
Up to 3 days
Truvada
8-12 wks after exposure
Prevention:
PREP:
- What does it stand for?
- Indications - 3
- Who is this used in?
Pre-exposure prophylaxis
In those with high-risk of acquiring HIV including serodifferent relationships:
- Condomless anal sex MSM - any anal sex without condoms in the past 6 months
- Heterosexual - HIV positive with partner
- IVDU
Needlestick injury:
What should be done as soon as you get a needle injury?
Where can you go to seek help for testing and post-exposure prophylaxis?
Encourage wound bleeding, ideally under running water
Wash with running water
Occupational health/infection control
WHO Staging and Disease Correlation:
Primary HIV infection - Acute Retroviral Syndrome.
Clinical Stage 1 - Asymptomatic:
- What do patient notice?
- Above what CD4 count?
Stage 2 - Minor symptoms:
- Cutaneous folliculitis
- What sort of rash can they develop and why?
- What CD4 range is used?
Stage 3 - Moderate symptoms:
- This is where the oral manifestations occur. What are the 2?
- Also get pul tuberculosis
- Persistent fever
- CD4 (350-200)
Stage 4 - AIDs-defining illness:
- Type of cancer?
- How is the brain affected?
- Lung infection?
- What sort of ulcers can you get?
- Cryptococcis - fungal infection - what can it affect?
- Under what CD4 are these seen in?
What stage do they begin getting persistent fever?
What stage do they begin to lose weight?
CD4 > 500
Persistent generalised lymphadenopathy - may also be asymptomatic
Dermatomal - Reactivation of VZV by HSV
Shingles**
Oral candidiasis
Oral hairy leukoplakia
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Kaposi sarcoma (can also get orally) Central nervous system Toxoplasmosis - leads to brain damage
PCP - pneumocystis pneumonia - desaturation on exertion
Herpes ulcer - chronic and widespread
Meningitis
Brain abscess
Infection may also be present as a brain abscess known as cryptococcomas, subdural effusion, dementia, isolated cranial nerve lesion, spinal cord lesion, and ischemic stroke. If cryptococcal meningitis occurs, mortality rate is between 10–30%.[28]
Stage 3
Stage 2 is when WL starts
