Diagnostic Ultrasound - Abdomen and Pelvis

Delayed Renal Graft Function
Diagnoses: Kidney Transplant
TERMINOLOGY
• Oliguria, poor clearance, and need for dialysis in 1st week
after transplantation
IMAGING
• Clinical diagnosis with no specific imaging findings
• May have elevated resistive indices or absence of diastolic
flow
• Renal transplant may be edematous
• Ultrasound with Doppler serves to exclude other causes of
renal transplant dysfunction
• Look for hemorrhage, vascular thrombosis, or
hydronephrosis
• Tc-99m mertiatide scintigraphy: Normal perfusion with
accumulation of activity in renal parenchyma
○ Minimal if any excretion
KEY FACTS
PATHOLOGY
• 21% incidence in deceased donor transplantation, 2-5%
after living donor transplantation
• Most common cause is acute tubular necrosis: 70-90%
• Risk factors
○ Donor age, harvest injury, preservation
○ Injury at procurement, organ preservation methods,
warm and cold ischemia time
CLINICAL ISSUES
• Present with oliguria, lack of renal function
• DGF has significant impact on long-term graft and patient
survival
• May be complicated by vascular thrombosis
• Treatment is supportive with dialysis as indicated
DIAGNOSTIC CHECKLIST
• Early biopsy (3-5 days in high-risk patients) to detect
coexisting early rejection
(Left) Longitudinal ultrasound
shows a nonfunctioning renal
transplant ſt on the 1st
postoperative day. The
transplant appears normal.
(Right) Pulsed Doppler
ultrasound in the same patient
with delayed graft function
shows absence of diastolic
flow ſt and narrow systolic
peaks. Venous flow is
present.
(Left) Longitudinal color
Doppler ultrasound shows a
nonfunctioning renal
transplant st with delayed
graft function. The transplant
is perfused, excluding vascular
thrombosis as a cause of
dysfunction. There was also no
hydronephrosis or collection.
(Right) Pulsed Doppler
ultrasound shows an elevated
resistive index of 0.81 ſt in
delayed graft function.
Perfusion is normal. Resistive
index is the ratio of peak
systolic velocity minus end
diastolic velocity to peak
systolic velocity.
580