Opportunistic infections

Question 1

What is. the difference between exogenous and endogenous opportunistic infections?

Answer 1

Exo - acquired from environment, more sever is immunocompromised

endo - latent virus that reactivates when immunosurpessed

Question 2

How do we detect viruses?

Answer 2

indirect - look for immune response to virus (can help see if you have HAD infection)

direct - looking for fragments of viral samples e.g. viral proteins in LFT or PCR
(can help see if you HAVE infection)

Question 3

What is serology?

Answer 3

measure of antibody levels in serum

IgM - active or resolving infection

IgG - past infection >6 weeks

Ig levels decrease in immunosuppression

Question 4

What are the markers of active viral replication in Hep A and B

Answer 4

Hep A - Hep A virus in stool

Hep B - Bep B surface antigen

Question 5

How do you detect opportunistic infections in immunocompromised pts?

Answer 5

Serology is not useful bc Ig decreases

Can do:
1. screen prior to immunosuppression to see if there is anything that could reactivate
(HepB and C, EBV, CMV, HSV, VZV,

2. PCR

Question 6

What increases risk of opportunistc viral infections?

Answer 6

DMARDs and steroids (LOWEST RISK)
Cytotoxic chemotherapy
Monoclonal antibodies 
Solid organ transplant 
Advanced HIV 
Allogeneic stem cell transplant (HIGHEST RISK)

Question 7

Which viruses typically occur early and late after a stem cell stransplant?

Answer 7

EARLY 
staph aureus 
viridans group strep (endocarditis)
HSV
Candida

LATE
CMV
Varicella 
EBV
toxoplasmosis
PCP

Question 8

What are the issues of HSV 1 and 2 in immunocompromised pts?

Answer 8

More organs are involved - can lead to eosophagitis/hepatitis (NOT ENCEPHALITIS)
can be resistance to acyclovir

Question 9

How is HSV managed?

Answer 9

check CD4 count and give HSV IgG prophylactically

Question 10

What are some complication of VZV?

Answer 10

pneumonitis
encephalitis
hepatitis
purpura fulminans in neonate

Question 11

How do we treat VZV?

Answer 11

Vaccinations

give IV antivirals

Question 12

What are some issues with EBV?

Answer 12

Oncogenesis - lymphoma

Post transplant lymphoproliferative disorder

Question 13

How do we manage EBV?

Answer 13

monitor EBV levels

reduce immunosupression if possible

Question 14

What are some complications of CMV?

Answer 14

retinitis
pneumonistis
encephalitis
gastroenteritis

Question 15

How do we treat CMV?

Answer 15

gancyclovir

reduce immunosuppression

Question 16

What is the difference between CMV infection in solid organ transplant vs stem cell transplant and how are they managed?

Answer 16

SOT - donor (organ) has CMV but the recipient doesnt so this is the first time the immune system will have met CMV THIS IS MORE HIGH RISK

Vanganciclovir for 100 days prophylaxis

Bone marrow stransplat - Donor didnt have CMV but the recipient does. The recipents immune system has now been replaced with one that has not seen CMV before

• CMV viral load twice weekly and treat if reactivates

Question 17

What is a key complication of JC virus and how does it present?

Answer 17

Progressive multifocal leukoencephalopathy

presents with cognitive disturbances, personality change, focal neurological deficits

caused by demyelination of white matter

Question 18

How can BK virus present?

Answer 18

haemorrhagic cystitis

nephrophathy

Question 19

How is influenza A/B treated?

Answer 19

Oseltamivir for 5 days

if resistance - zamtamivir

Question 20

What can increase risk of Hep B activation?

Answer 20

rituximab - anit CD19

Anti IL 6