Renal Transplant

Question 1

where do you typically find transplant kidneys attached to?

Answer 1

attached to the hypogastric artery and external iliac vein and placed into anterior iliac fossa (R>L)

Question 2

RP and dose

Answer 2

MAG3 or DTPA

Question 3

imaging protocol

Answer 3

dynamic imaging (see the flow of blood to kidney)
immediate static of abdomen?

Question 4

during flow phase… activity should appear in the kidney within _____

Answer 4

2-5 secs of appearing in the adjacent iliac artery

Question 5

during the functional phase, peak activity at ____

Answer 5

3-5 mins

Question 6

during the clearance phase, filling of calyces and pelvis by ______

Answer 6

3-5 mins

Question 7

bladder typically seen by ____ in the clearance phase

Answer 7

4-8 mins

Question 8

medical pathologies that are unique to renal transplants

Answer 8

• rejection (hyperacute, accelerated acute, acute, chronic)
• acute tubular necrosis/delayed graft function
• immunosuppressive drug toxicity/nephrotoxicity

Question 9

surgical pathologies that are unique to renal transplants

Answer 9

• urine extravasation (urinoma)
• hematoma
• lymphocele
• renal artery or vein thrombosis
• ureteral obstruction

Question 10

symptoms of tx complications

Answer 10

• decreased renal function
• HTN
• weight gain
• tenderness and graft swelling but no renal pain
• fever
• proteinuria, hematuria, lymphocytes in urine
• elevated creatinine and urea

Question 11

hyperacute

Answer 11

within minutes of tx
obvious in OR

Question 12

accelerated acute

Answer 12

1-5 days post tx

Question 13

acute

Answer 13

7+ days post tx
most likely in first 2-3 months

Question 14

what type of rejection is typically seen in NM?

Answer 14

acute and chronic

Question 15

chronic

Answer 15

months to years

Question 16

what type of tx rejection has cellular mediated immune response?

Answer 16

acute

Question 17

what type of tx rejection has antibody mediated immune response?

Answer 17

chronic

Question 18

appearance of acute rejection

Answer 18

decreased perfusion and diminished uptake and excretion

Question 19

appearance of chronic rejection

Answer 19

initially looks normal
serial imaging = slow decline in renal function, increased parenchymal retention, delayed excretion = cortical thinning and patchy uptake

till eventually no uptake at all (renal failure)

Question 20

how do you reduce the risk of rejection?

Answer 20

a nice drug cocktail that has a strict timing regimen

Question 21

what mimics renal tx rejection?

Answer 21

cyclosporine/tacrolimus toxicity

Question 22

another term for acute tubular necrosis (ATN)

Answer 22

delayed graft function

Question 23

what is ATN?

Answer 23

ischemia that happened between harvest and transplant

Question 24

symptoms of ATN

Answer 24

decreased urine output within first few days after tx (will resolve within few days to weeks)

Question 25

renogram of ATN

Answer 25

minimally decreased perfusion decreased function therefore increased cortical retention improves in serial imaging!

Question 26

differentiate between ATN and drug toxicity renograms

Answer 26

they look similar, normal perf, but due to reduced function there will be retention of tracer

Question 27

what is the key to diagnosing ATN vs. drug toxicity?

Answer 27

dependent on when study was done. if seen during exam that was done within 2 days of post tx = ATN while if done weeks to months post tx = drug toxicity

Question 28

which RP is useful to test for leaking?

Answer 28

MAG3 as it has better T:NT

Question 29

which RP is better to few potential reduced functioning kidneys?

Answer 29

DTPA as MAG3 as hepatobiliary excretion

Question 30

appearance of surgical urine leaks and urinomas

Answer 30

urine outside collecting system, ureters or bladder can be seen as photopenic defect if it is a slow leak and/or cyst with urine inside

Question 31

appearance of a hematoma

Answer 31

photon deficient area for the first few days after tx

Question 32

appearance of lymphocele

Answer 32

photon deficient area for the first 2-4 months after tx

Question 33

what is lymphocele?

Answer 33

extrarenal collection of lymphatic fluid that can cause ureteral or iliac vein compression

Question 34

appearance of vascular complications

Answer 34

photopenic kidney with possible hot rim