Teaching Case

A fifty-two-year-old male patient who had recently undergone a renal transplant reported to the hospital for his regular follow up, when the transplant team noted an unusual and unexpected raise in the serum creatinine levels of the patient.

The patient was then referred for an ultrasound and Doppler of the transplant kidney which showed hydroureteronephrosis with normal Doppler findings. Following this the patient underwent non-enhanced CT abdomen which confirmed the findings. This prompted the transplant team to refer the patient for a percutaneous nephrostomy to the intervention radiology team. A 10 F Pig Tail was placed in the dilated system. CT nephrostogram showed a distal ureteric stricture which was the cause of obstruction.
An antegrade uretric stenting was planned. Check nephrostogram showed distal ureteric obstruction. Balloon plasty was performed across the distal ureteric stricture and a double J stent was placed. The patient showed improvement with reduction in the serum creatinine on follow up.

Renal transplant was first successfully performed in 1954 and has become the treatment of choice for end stage renal failure worldwide. Newer surgical techniques and immunosuppressants have improved graft survival. Despite all advances 12-20% of patients can present with post-transplant complications [1]. Complications can be divided into a) Nephrogenic, b) Urologic and c) Vascular. Ultrasound is the first imaging modality in post-operative period and during follow up. CT is useful for demonstrating parenchymal and vascular abnormalities. MRI has become an excellent modality for assessing in post-transplant patients. Urinary obstruction is seen in up to 2% of patients and most commonly occurs within the first six months [2]. The most common cause is stricture in the distal third, anastomotic site oedema, perinephric free fluid and clot. A transplant kidney is denervated and does not show classic symptoms when obstructed and raised serum creatinine may be the only early sign suggestive of obstruction. Ureteric obstruction can be two types: early (<3 months) and late (>3 months). Early obstruction is treated by percutaneous management, however, late obstruction cannot be treated due to its recurrent nature. Percutaneous management includes percutaneous nephrostomy, balloon plasty, double J stent and rarely metal stent. Percutaneous nephrostomy is used to relieve obstruction and also to perform other interventional procedures. Balloon plasty has a technical success rate of 100% for early obstruction [3]. Kashi et al. compared percutaneous stenting versus surgery and found 100% success in percutaneous stenting versus 87% in surgery [4].

Written informed patient consent for publication has been obtained.