Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Infection - Alex's Cards (ESA2) > Session 8 Lecture Notes > Flashcards

Session 8 Lecture Notes Flashcards

1
Q

In immunosuppressed patients such as those with HIV which pathogens become prevalent?

A

Viruses - reactivation of latent viruses
Parasites - protozoa in particular
Fungi - yeast and mound in particular

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

In the U.K. is it heterosexual men or MSM who have majority of HIV?

A

Majority in UK is MSM

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

HIV is a retrovirus - what does this mean? How does this work in infecting the host cell?

A

HIV has a single stranded RNA genome (ssRNA)
When the HIV virus has infected an APC (with a CD4 receptor) the RNA is converted to DNA using reverse transcriptase
The DNA is incorporated into the host cell’s DNA by integrase
When the DNA is read it then creates new viral proteins and these comes together - double stranded RNA
Retrovirus = ssRNA –> DNA –> dsRNA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are the 4 main ways HIV can be transmitted?

A
  1. Sexual contact
  2. Transfusion
  3. Contaminated Needles
  4. Vertical transmission (either through infected birth canal or through digestion of breast milk)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

At what CD4 count does HIV become AIDS?

A

Below 200

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What other factors may affect HIV transmission?

A
  • Type of exposure (type of sexual act or whether it was a transfusion or needlestick injury)
  • Viral load in the blood (lower risk if this is lower)
  • Condom use
  • Breaks in the skin increase the risk (eg from other STIs or if it was an aggressive sexual assault)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the only type of transmission that has a risk of 90-100%

A

Transfusion of one unit of infected blood

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are the 3 diagnostic tests for HIV?

A
  1. Blood tests - serology
  2. Blood tests - PCR
  3. Rapid tests
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What will a blood serology test for HIV look for?

What is the risk with this test?

A

It will look for HIV antigen and HIV antibodies

Risk: if the test is carried out too soon then you may get false negative results

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What will a blood test for PCR look for?

A

It detects HIV nucleic acid and can detect very early infection
It is not used for initial HIV testing as very expensive

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What do rapid tests for HIV do? What are the risks with this?

A

They detect the HIV antibody
Can be done using a finger prick, saliva sample and at home
Risk: if negative = accurate, if positive = not always accurate (can get false positive results)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What treatment would you give a patient with HIV?

A

Anti-retroviral drugs (ARV)
Specifically:
TWO nucleoside reverse transcriptase inhibitors
AND
non nucleoside reverse transcriptase inhibitor
OR
protease inhibitor
OR
integrase inhibitor
OR
entry inhibitor (target CCR5 - coreceptor)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is post exposure prophylaxis?

A

Giving a person ARV drugs if they think they may have been exposed to HIV as a preventative measure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is pre exposure prophylaxis?

A

Giving a person ARV drugs before they become exposed to HIV (if the person is in a relationship with someone with HIV)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is the consequence of untreated Hep B?

A

10% chance of developing liver cirrhosis

Risk of developing hepatocellular carcinoma (liver cancer)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is the consequence of untreated Hep C?

A

80% develop liver cirrhosis

Risk of developing hepatocellular carcinoma (liver cancer)

17
Q

What is the definition of hepatitis?

A

Inflammation of the liver

18
Q

Where does the hepatitis virus replicate and destroy cells?

A

Replication is in hepatocytes (liver)

Destruction therefore of hepatocytes

19
Q

Describe the hepatitis B and C viruses = genome and if enveloped

A

Hep B = dsDNA and enveloped

Hep C = ssRNA and enveloped (icosahedral in shape)

20
Q

What are the 3 types of jaundice?

A
  1. Prehepatic jaundice (excess bilirubin caused before the liver eg hemolysis)
  2. Intrahepatic jaundice (excess bilirubin caused by liver eg viral hepatitis preventing conjugation of bilirubin and it builds up in blood)
  3. Extrahepatic jaundice (excess bilirubin caused after the liver eg bile duct carcinoma)
21
Q

In a patient with hepatitis what would you be looking at in their liver function test? 6 key things

A
  1. Bilirubin levels
  2. ALT levels (alanine transaminase)
  3. AST levels (aspartate transaminase)
  4. ALP levels (alkaline phosphatase)
  5. Albumin levels
  6. Coagulation factors - PTT and INR etc
22
Q

Blood test results show:

  • high bilirubin
  • high ALT
  • normal haemoglobin

what type of jaundice is this?

A

Intrahepatic jaundice

  • high ALT = damage to liver
  • normal hemoglobin = not due to hemolysis as this would show low too
23
Q

With hepatitis B are you

more at risk of developing a chronic infection when a child or an adult?

A

When a child = 90% of cases become chronic if infected as a child compared to 10% as an adult

24
Q

In Hepatitis B serology what antigens would you expect to see?

A
  1. HBsAg (Hepatitis B surface antigen)
  2. HBeAg (Hepatitis B E antigen)
  3. There is a HBcAg but this only appears in the liver tissue NOT bloodstream
25
Q

In Hepatitis B serology what antibodies would you expect to see?

A
  1. HBsAb = Hepatitis B surface antibody
  2. HBeAb = Hepatitis B E antibody
  3. HBcAb = Hepatitis B core antibody (the C antigen is only found in the liver tissue but the antibody appears in the bloodstream)
26
Q

In Hep B serology what is the order in which you would see antigens and antibodies?

A
  1. HBsAg
  2. HBeAg
    ( the 2 antigens in the blood appear first)
  3. HBcAb (IgM)
  4. HBeAb
  5. HBsAb
  6. HbcAb (IgG) this means the person is no longer infected and have created antibodies for life
27
Q

What is the definition of a chronic Hep B infection?

A

Persistence of HbsAg after 6 months

28
Q

How long until a person is cured from Hep B?

A

A person can never be cured - anti virals taken for life

However some may be inactive carriers and not require anti-virals as viral load is so low

29
Q

What is the vaccination against Hep B?

A

Genetically engineered Surface antigen

30
Q

How many of patients with Hep C will become chronically infected?

A

80% of patients

31
Q

What would you look for in blood serology with Hep C?

A

Anti hep C antibody only

32
Q

Can Hep C be cured?

A

Yes with antiviral drugs

BUT a person can get re-infected

33
Q

What is the vaccine for Hep C?

A

There is no vaccine

Infection - Alex's Cards (ESA2) (8 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions