BK virus Flashcards
What is BK seroprevalence in population?
60-80%
What is BK route of transmission?
unclear
respiratory droplets/ saliva
organ transplant
vertical transmission
After renal transplant, how often is routine BK virus screening performed?
Varies
Perform weekly for 4 months then
perform monthly until end of ear 2 then
perform annual testing
perform testing is any unexplained risk in creatinine
Renal transplant patient
Routine BK result comes back as 1000 copies
What action do you take?
Repeat viral load in a week
check for rise in creatinine
monitor if stable
Renal transplant patient
Routine BK result comes back as 1000-5000 copies
What action do you take?
if this has risen from previous value, then aim to decrease immunosuppression
send repeat sample in a week
Renal transplant patient
Routine BK result comes back as 10,000 copies
What action do you take?
consider renal biopsy - to prove that BK viraemia represents BK nephropathy
reduce immunosuppression
- if need to stop immunosuppression totally, consider adding Leflunomide - although not much evidence for this
consider IVIG - although not much evidence of this
monitor viral load
BK nephropathy confirmed on biopsy
You have reduced immunosuppression, but now considering Leflunomide
What are benefits of this?
In renal tubular epithelial cells, leflunomide was reported to reduce BK virus replication by its DNA synthesis inhibitory effects
Also acts as immunosuppressant - which helps prevent rejection given you have reduced other immunosuppression
not much evidence for benefit
What is mechanism of action of leflunomide?
Leflunomide - DMARD. Pyrimidine synthesis inhibitor
What is a contra-indication to leflunomide
Pregnancy
Which renal transplant patients are at highest risk of BK nephropathy?
Renal transplant within past 3 months
Previous history of rejection due to BK virus
BK nephropathy proven on biopsy
How do you treat?
Reduce immunosuppression
No specific treatment available
Hydration/ bladder irrigation
Platelets to reduce bleeding
analgesia
cidofovir has been used IV/intra-vesicular, but lack of evidence in RCTs
IVIG may be used if this is the primary immunodeficiency
