Renal Transplant

Question 1

Most common technical (surgical) complication of renal transplants

Answer 1

related to the ureteric anastomosis.

Question 2

Graft survival is directly related to what “time”?

Answer 2

“warm ischaemic time”

=> Long warm ischaemic times increase the risk of acute tubular necrosis

Question 3

Name the 3 types of organ rejection which can occur following renal transplant

Answer 3

Hyperacute
- immediate
- pre-formed antibody (e.g. ABO incompatibility)

Acute
- in first 6 months
- T cell mediated
- causes tissue infiltrates and vascular lesions

Chronic
- after the first 6 months
- Vascular changes predominate

Question 4

Risk factors for hyperacute rejection of renal transplant

Answer 4

• major HLA mismatch
• ABO incompatibility.

Question 5

Describe the appearnce of a hyperacute rejection after completion of the vascular anastomosis and removal of clamps.

Answer 5

• kidney becomes mottled/dusky
• vessels will thrombose

Question 6

Treatment of hyperacute rejection

Answer 6

• removal of the graft

Question 7

If you leave the renal transplant in situ following a hyperacute rejection, what will occur?

Answer 7

abscess formation

Question 8

What increases the risk of a chronic organ rejection

Answer 8

• Previous acute rejections
• other immunosensitising events

Question 9

What is the most common cause of a chronic graft rejection? How does this occur?

Answer 9

Vascular changes

=> myointimal proliferation leading to organ ischaemia

Question 10

What technical complication is described below?

Sudden complete loss of urine output

Answer 10

renal artery thrombosis

Question 11

What technical complication is described below?

Uncontrolled hypertension, allograft dysfunction and oedema

Answer 11

Renal artery stenosis

Question 12

What technical complication is described below?

Pain and swelling over the graft site, haematuria and oliguria

Answer 12

renal vein thrombosis

Question 13

What technical complication is described below?

Diminished urine output, rising creatinine, fever and abdominal pain

Answer 13

urine leaks

Question 14

What technical complication is described below?

Common complication (occurs in 15%), may present as a mass, if large may compress ureter

Answer 14

lymphocele

Question 15

Management of transplant associated renal artery thrombosis

Answer 15

Immediate surgery may salvage the graft

delays >30 mins = high rate of graft loss

Question 16

Management of transplant associated renal artery stenosis

Answer 16

Angioplasty

Question 17

Management of transplant associated renal vein thrombosis

Answer 17

Management options poor, graft often lost

Question 18

Findings on investigation of suspected urine leak following renal transplant

Answer 18

US-perigraft collection
necrosis of ureter tip

Question 19

Management of urine leak in renal transplant

Answer 19

anastomosis revision

Question 20

Management of a lymphocele following renal transplant

Answer 20

percutaneous drainage and sclerotherapy

OR intraperitoneal drainage

Question 21

What is HLA?

Answer 21

human leucocyte antigen (HLA) system is the name given to the major histocompatibility complex (MHC) in humans.

Question 22

Which chromosome codes for HLA?

Answer 22

Chromosome 6.

Question 23

give examples of class 1 and class 2 HLA antigens

Answer 23

class 1 antigens: A, B and C. Class 2 antigens: DP,DQ and DR

Question 24

Importance of Class 1 vs class 2 HLA antigens in renal tranplsant

Answer 24

DR>B>A

Question 25

Rate of graft survival in renal transplants

Answer 25

Cadaveric transplants: 1 year = 90%, 10 years = 60% Living-donor transplants: 1 year = 95%, 10 years = 70%

Question 26

Post-op problems following renal transplant

Answer 26

ATN of graft vascular thrombosis urine leakage UTI

Question 27

What type of graft rejection occurs in mins-hours?

Answer 27

Hyperacute

Question 28

Cause of hyperacute graft rejection

Answer 28

- pre-existing antibodies against ABO or HLA antigens (Type II hypersensitivity) => widespread thrombosis of graft vessels → ischaemia and necrosis of the transplanted organ

Question 29

how is a hyperacute graft rejection managed?

Answer 29

no treatment is possible and the graft must be removed

Question 30

For how long after transplant is still considered an acute graft rejection?

Answer 30

6 months

Question 31

What causes an acute graft rejection?

Answer 31

- mismatched HLA - Cell-mediated (cytotoxic T cells) - other causes e.g. CMV

Question 32

how can an acute graft rejection be identified?

Answer 32

- picked up by a rising creatinine, pyuria and proteinuria

Question 33

how is acute graft rejection treated?

Answer 33

may be reversible with steroids and immunosuppressants

Question 34

What is considered chronic graft rejection?

Answer 34

>6 months post transplant

Question 35

Cause of chronic graft rejection

Answer 35

- antibody and cell-mediated fibrosis - OR recurrence of original renal disease e.g. MCGN > IgA > FSGS

Question 36

What original renal disease is most likely to represent as chronic graft rejection?

Answer 36

MCGN > IgA > FSGS

Question 37

give an example of a usual intial and maintenance immunosuppression regime following transplant

Answer 37

Initial: - Ciclosporin/tacrolimus + MAB Maintenance: - ciclosporin/tacrolimus with Mycophenolate Mofetil or sirolimus

Question 38

Calcineurin inhibitor, (Calcineurin is a phosphotase involved in T cell activation)

Answer 38

Ciclosporin

Question 39

Tacrolimus has a lower incidence of acute rejection compared to ciclosporin TRUE/FALSE

Answer 39

TRUE

Question 40

Tacrolimus causes less hypertension and hyperlipidaemia than ciclosporin. TRUE/FALSE?

Answer 40

TRUE

Question 41

Tacrolimus has a higher incidence of what side effects compared to ciclosporin?

Answer 41

impaired glucose tolerance and diabetes

Question 42

Which immunosuppressant blocks purine synthesis by inhibition of IMPDH? => inhibits proliferation of B and T cells

Answer 42

Mycophenolate mofetil

Question 43

Common side effects of mycophenolate mofetil?

Answer 43

GI and marrow suppression

Question 44

Which immunosuppressant blocks T cell proliferation by blocking the IL-2 receptor?

Answer 44

Sirolimus (rapamycin)

Question 45

Side effect of sirolimus

Answer 45

hyperlipidaemia

Question 46

Which monoclonal antibodies (IL2 inhibitors) are used in renal transplant immunosuppression?

Answer 46

daclizumab basilximab

Question 47

What should be monitored when patients are on long term immunosuppression following a renal transplant?

Answer 47

Cardiovascular disease - (due to s/e of hyperlipidaemia and hyperglycaemia) Renal failure - look for graft faillure Malignancy - risk of squamous cell carcinomas and basal cell carcinomas when on immunosuppression