Renal transplant torsion

Renal transplant torsion is a very rare complication of renal transplant, occurring mostly in intraperitoneal transplants because of the increased mobility compared to extraperitoneal transplants, which are less mobile.

Clinical presentation

Non-specific clinical symptoms such as nausea, abdominal pain, decreased urine output and elevated creatinine.

Pathology

Torsion occurs around the vascular pedicle of the renal transplant and can result in vascular compromise and infarction .

Radiographics features

A change in the axis in the iliac fossa of the renal transplant is the most suggestive finding of torsion . Torsion can be complete or incomplete as well as being intermittent. A normal-appearing examination cannot exclude torsion.

Ultrasound

• incomplete torsion results in venous compromise generating an elevated resistive index (RI) and peak systolic velocity (PSV) at the main transplant renal artery anastomosis
• with complete torsion, arterial compromise can result in a decrease in the RI and complete absence of flow on color Doppler
• with ureteric torsion, the renal transplant becomes swollen and enlarged with the development of hydronephrosis

CT

• vascular "kinking" may be observed
• on post-contrast imaging, contrast enhancement may be delayed or absent