Deborah J. Conway, MD
Michael P. Carter, MD
from the Department of Radiology,Memorial Health University
Medical Center, Savannah, GA. Dr. Conway is now a Pediatric
RadiologyFellow at Children's Hospital, Seattle, WA.
A 73-year-old white male whocomplained of abdominal pain
underwent a contrast-enhanced computed tomography (CT) examination
of the abdomen (Figure 1). Thisstudy revealed an infrarenal
abdominal aortic aneurysm measuring 8 cm in greatest
anteroposterior diameter. Contrastopacification of both kidneys was
shown on this CT.
Five days later, the patient developed anelevated serum
creatinine level as well as high-output congestive failure. Another
CT of the abdomen was performed (Figure 2) thatdemonstrated
opacification of the aorta, inferior vena cava (IVC), and left
renal vein to the same degree with intravenouscontrast with near
absent perfusion of the left kidney.
The patient underwent aortography. A floppyJ-wire was inserted
through the aortic aneurysm into the left renal vein and
subsequently into the IVC (Figure 3). Followingcontrast
administration, there was rapid visualization of the left renal
vein as well as the IVC (Figure 4).
Spontaneous aorta-left renal veinfistula
An abdominal CT obtainedupon the patient's initial presentation
to an outside facility shows a fusiform abdominal aortic aneurysm
with focal contourdeformity posteriorly, anterior to a retroaortic
left renal vein (Figure 1). There is contrast opacification of the
aorta,left renal vein, and IVC to the same degree; both kidneys are
perfused. A second abdominal CT obtained 5 days following the
initialpresentation again reveals focal contour abnormality of the
posterior abdominal aortic aneurysm directly anterior to the left
renalvein with enhancement of the aorta, IVC, and left renal vein
to the same degree; however, the left kidney is now minimally
perfused(Figure 2). An abdominal aortogram obtained upon
presen-tation to our facility demonstrates passage of a wire into
the rightfemoral artery, through the fistula, into the left renal
vein and, finally, into the IVC (Figure 3). Contrast injectedinto
the upper abdominal aorta is immediately seen within the aorta,
left renal vein, and IVC simultaneously, showing thefistula between
the aorta and left renal vein (Figure 4).
Many complications of abdominalaortic aneurysm have been
described, the most common being rupture. A less commonly described
complication is the development of afistula from the enlarged aorta
to other nearby structures. A number of cases of aorta-caval
fistulas have beendescribed in medical literature. Iliac vein and
enteric fistulas have also been described. Other vascular
communications arefar less common. This case demonstrates the
spontaneous development of a fistula between an abdominal aortic
aneurysm and aretroaortic left renal vein. An English literature
search revealed only 20 reported cases
of spontaneous aorta-left renal vein fistula; however, none of
these reports indicated the evolution ofsuch a fistula with
radiographic imaging. Almost all of these patients had a
retroaortic left renal vein.
Prior reports have described a clinical syndrome of abdominal
pain,pulsatile abdominal mass, elevated serum creatinine,
hematuria, and nonperfusion of the left kidney on imaging studies.
Often, as serum creatinine rises due to nonperfusion of the left
kidney, treatment is delayed asa primary renal problem is
Also, physicians are reluctant to perform a CT ofthe abdomen with
contrast due to poor renal function, again delaying the
Sultan et al
describe an attempt at endovascular repair with a stent graft that,
although it was unsuccessfulin that particular case, suggests a
minimally invasive approach might be used in the future.
Although an aorta-left renal veinfistula is a rare entity, this
diagnosis must be suspected in a patient with abdominal aortic
aneurysm, hematuria, andworsening renal function. Also,
endovascular repair should be considered, especially in patients
with a high surgical risk.