PICTORIAL

Aorto-caval Fistula Mimicking Clinical Signs of Renal Colic

Zbyněk Tüdös1, Filip Čtvrtlík1*, František Hruška2, Milan Král2

Keywords: urolithiasis; renal colic; aortic rupture; aorto-caval fistula; non-enhanced computed tomography; 
angiography

1Department of Radiology, Faculty of Medicine and Dentistry, Palacky University and University Hospital, Olomouc, Czech Republic
2Department of Urology, Faculty of Medicine and Dentistry, Palacky University and University Hospital, Olomouc, Czech Republic
*Correspondennce: Department of Radiology, University Hospital, I. P. Pavlova 6, Olomouc, 77900, Czech Republic 
Email: filip.ctvrtlik@fnol.cz.
Received July 2017 & Accepetd Februaty 2018

A 71-year-old male came to the emergency room complaining of weakness, nausea and pain in the left flank and groin irradiating into his left hemiscrotum. Clinical examination revealed arterial hypotensis and tachy-
cardia. Because of the patient’s history of urolithiasis in the past, left renal colic was suspected and non-enhanced 
computed tomography (CT) was requested. The CT scan confirmed nephrolithiasis, but the crucial finding was an 
aneurysm of the abdominal aorta measuring 95 mm in diameter. Furthermore, the dorsal wall of the aorta was in 
direct contact with the spine, creating a “draped aorta sign” (Figure 1a). There were hyperdense bands along the 
aorta, the psoas muscles and the Gerota’s fascia corresponding to retroperitoneal hematoma (Figure 2b)(1). The 
CT finding was immediately reviewed and CT angiography was promptly performed to evaluate the suspected 
acute aortic rupture. Contrast-enhanced angiography confirmed an aortic rupture with fistula to the inferior vena 

Figure 1. Non-enhanced computed tomography initially per-
formed to confirm suspected left renal colic. A) displays ab-
dominal aorta aneurysm and the disappearance of fat plane 
between the aorta and the spine and the merging of the con-
tours of the two structures, thus creating a “draped aorta sign” 
(arrows), which is considered a sign of impending aortic rup-
ture. B) displays hyperdense bands along the aorta, the psoas 
muscles and the Gerota’s fascia (arrows), corresponding to 
retroperitoneal hematoma as a sign of acute aortic rupture.

Figure 2. Contrast-enhanced CT angiography performed to 
evaluate the extent of the suspected aortic rupture. Images in 
A) the axial and B) the coronal plane offer direct evidence 
of aortic rupture with 5-mm-wide fistula to the inferior vena 
cava (arrows). 

Urology Journal/Vol 17 No. 1/ January-February 2020/ pp. 107-108. [DOI: 10.22037/uj.v0i0.5633]



cava (Figure 2), and the lumen of the vein was homog-
enously enhanced in arterial phase (Figure 3). The pa-
tient underwent urgent surgery with partial resection of 
the aneurysm and implantation of an aorto-iliac bypass 
graft. This case illustrates the broad and tricky differ-
ential diagnosis of renal colic and also the diagnostic 
capabilities of non-enhanced CT.

ACKNOWLEDGMENTS
“Supported by Palacky University grant IGA_
L F _ 2 0 1 8 _ 0 0 2 ” .

REFERENCES
 1.  Cerna M, Kocher M, Thomas RP. Acute 

aorta, overview of acute CT findings and 
endovascular treatment options. Biomed Pap 
Med Fac Univ Palacky Olomouc Czechoslov. 
2017;161:14-23. 

Figure 3. Volume rendering reconstruction of CT angiography. 
Contrast filling of the inferior vena cava in arterial phase is clearly 
seen.

Aorto-caval fistula with renal colic-Tudos et al.

Pictorial   108