HIV and secondary immunodeficiency Flashcards
(22 cards)
Whats more common, Primary or secondary immunodeficiencies?
Secondary are more common
What are common causes of secondary immune deficiencies?
- Malnutrition (most common)
- Infection - HIV, TB
- Age extremes
- Immuno suppressive drugs
What kind of clinical features can be exhibited in a patient with an immune deficiency?
- Infections
- Severe, persistent, recurrent, unusual - Autoimmune conditions
- Persistent inflammation
- Cancer (associated with EBV)
What are some common drugs that can cause immune deficiency?
- Small molecules
- Glucocorticoids and mineralcorticoids
- cytotoxic agents (methotrexate) - JAK inhibitors
- Tofacitinib
What are some haematological cancers associated with immune deficiency?
- B cell lymphoproliferative disorders
- Multiple myeloma
- CLL
- NHL - Goods’ syndrome
How do you evaluate a possible secondary immune deficiency?
- clinical history of infection
- History of other illnesses (autoimmune)
- FHx
- Medication Hx
- Vaccine Hx
How do you investigate for a possible immune deficiency?
FISH for an immunodeficiency
- Full blood count
- Anaemia
- neutrophil count
- lymphocyte count
- platelet count - Immunoglobulins
- Serum complement
4 HIV test
How do you manage someone with a secondary immune deficiency?
- Treat underlying cause
- Advice on measures to reduce exposure
- Offer vaccines to patient + household contacts
- Prophylactic antibiotics
What is the structure of HIV?
Retrovirus (RNA virus that uses reverse transcriptase)
Double stranded RNA
Slow evolution of disease
What is the life cycle of HIV?
- Attachment
CD4 - Reverse transcription and DNA Synthesis
Reverse Transcriptase Inhibitors (Nucleoside&Non-Nucleoside) - Integration
Integrase Inhibitors - Viral Transcription
5. Viral Translation Protease Inhibitors (Here, the proteins are cleaved to form mature proteins)
- Assembly and release of Virus
- Maturation
What are the 3 markers measured for the clinical course of HIV?
- Plasma Viral Load,
- CD4+ Lymphocytes,
- CD8+ Lymphocytes.
What are the two predominant ways of diagnosing HIV?
i) Viral Load (PCR)
- > This is very sensitive and can identify HIV in patients who are yet to seroconvert
- > Steps involved include; reagent preparation, specimen preparation, amplification and detection
ii) anti-HIV antibodies (ELISA)
- > in the UK, 3 ELISA’s are used with three different formats to avoid false positives
- > It is then confirmed using a Western Blot.
What are the 5 characteristics features of the immunology of HIV infection?
- CD4 T cell depletion
- Chronic immune activation
- Impairement of CD4 and CD8 T cell function
- Disruption of lymph node architecture
- Loss of antigen specific humoral immune responses
What are the characteristics of an acute HIV infection?
- Significant increase in HIV viral load
- “Flu like” symptoms
- Significant risk of viral transmission
- Reduction in CD4+ T cells
- Increase in CD8 T cell = results in drop in VL
- Induction of HIV specific antibodies
A viral load of how much is considered undetectable?
-> A HIV Viral Load of <40copies/mL is considered undetectable
What are some baseline investigation for a patient with HIV?
- FBC
- Renal, liver, bone, lipid and HbA1c (for drugs)
- Sexual health screen
- ECG and CXR
- Toxoplasma serology
What are some HIV specific tests?
- HIV viral load
- HIV genotype (drug resistance)
- T cell counts
Why do you check CD4 T cell count?
To stratify the risk of different infections
What is the treatment for HIV?
- Test and trace
- HAART to treat patients
- PReP and PeP
What are the limitations and complications of HAART?
- > Effective HAART does NOT eradicate latent HIV-1 in the host
- > Fails to restore HIV-specific T-cell responses
- > Threat of drug resistance
- > Significant toxicities
- > High pill burden
- > Adherence problems
- > Quality of life issues
- > Cost: >40% infected do not have access to drugs
- > STIGMA
What is HAART?
Highly active antiretroviral therapy, combination of 3 drugs (2 NRTIs and one other)
Used to:
- > Suppresses the Viral Load
- > Rise in CD4 especially memory T Cells
How do you monitor patients on HAART?
- Compliance
- HIV viral Load
- Liver, renal, bone, lipid toxicity
- CD4 count
- Assess cardiovascular and osteoporosis risk
