Diagnostic Ultrasound - Abdomen and Pelvis

Perigraft Fluid Collections
Diagnoses: Kidney Transplant
TERMINOLOGY
• Perigraft fluid collections (PFC) include hematomas,
seromas, urinomas, lymphoceles, and abscesses
• Depending on size and location, PFC may cause mass effect
on allograft resulting in hydronephrosis or graft
dysfunction
• Lymphoceles, most common PFC, occur in 5-15% patients,
usually after 4 weeks
• Urinomas occur in 2-5% of patients secondary to
anastomotic leak or ureteric ischemia within first 2 weeks
IMAGING
• US is first-line modality for evaluating graft dysfunction,
excellent for PFC
• Collection of simple or complex fluid around renal allograft,
typically walled off
• CT superior for larger collections, local consequences, as
well as other abdominopelvic complications
KEY FACTS
• Multidetector CT urography (CTU) superior to intravenous
pyelogram in detecting urine leaks and ureteral obstruction
• Contrast cystography can demonstrate ureterovesical
anastomotic leak
• Definitive diagnosis established by US-guided needle
aspiration
• Aspiration of PFC to drain the collection and rule out
infection
• Aspirate should be tested for creatinine, markedly elevated
in urine leak
TOP DIFFERENTIAL DIAGNOSES
• Ovarian cysts
• Renal cyst
• Peritoneal inclusion cyst
• Penile prosthesis reservoir
• Pseudomyxoma peritonei
(Left) Longitudinal color
Doppler US shows a right
lower quadrant renal allograft
. The allograft is well
perfused despite a large,
acute, echogenic perinephric
hematoma st. (Right)
Longitudinal US shows a renal
allograft with moderate
hydronephrosis . The
transplant ureter was
compressed by a large
lymphocele st, and a ureteral
stent is present .
(Left) Longitudinal color
Doppler US shows a renal
transplant with mild
hydronephrosis st. Although
there was a small hematoma
ſt posterior to the transplant,
this was not the cause of the
hydronephrosis. (Right)
Longitudinal US shows a
chronic hematoma in the right
pelvis. There are multiple thick
and irregular septations ſt
with more solid, avascular
areas st. Some loculi contain
echogenic fluid .
562