Forgotten Indwelling Double J Ureteral Stent : A Case Report and Suggested Treatment Algorithm

Short term placement of double-J (D/J) ureteral stents after endourological or open surgical procedures is routine. A forgotten or retained ureteral stent is a rare entity and frought with complications. We report a case of forgotten D/J ureteral stent placed after open surgery for renal calculi who presented with pyonephrosis with stone formation over the vesical and renal ends of stent. A staged treatment comprising Percutaneous Nephrostomy (PCN) followed by cystolithotripty, ESWL and cystoscopic removal of stent was carried out. A treatment algorithm is proposed and prevention is discussed.

Introduction

Ureteral stents are frequently used in endourological and open surgical procedures to relieve and prevent obstruction of the urinary tract and to maintain its patency. ‘Stent syndrome’ comprising dysuria, frequency, flank pain and haematuria is commonly seen with short term placement.¹ Migration, encrustations and obstruction/blockage of stent occurs following long term retention of stent. Fracture of stent is a rare complication.


Fig. 1 : X-ray KUB showing a D/J stent with a 3 mm encrustation over its renal coil and a huge calculus formed on the vesical coil. Inset : shows the removed D/J stent with the encrustations.

Fig. 2 : Shows Intavenous urography (IVU) showing nonfunctioning left kidney. Inset : shows a left Percutaneous Nephrostomy (PCN).

Case Report

A 25 year male presented with fever, left flank pain, dysuria and pyuria of one week duration. He gave a past history of having undergone an open surgical procedure for “renal calculi” at a peripheral hospital 4 years back. Examination revealed a febrile patient with left flank tenderness and a well healed flank incision. Total leucocyte count was 16,000/cu mm with 90% polymorphonuclear leucocytes. X-ray KUB revealed a D/J stent with a 3 mm encrustation over its renal coil and a huge vesical calculus (5x5 cms) formed on the vesical coil (Fig. 1). On detailed enquiry, the patient denied of having any knowledge of intra operative stent placement. Ultrasonography (USG) revealed gross hydronephrosis of the left kidney with internal echoes and thinning of parenchyma. Serum Creatinine was normal. Intravenous urography (IVU) showed a nonfunctioning left kidney (Fig. 2). Under the cover of IV Gatifloxacin, a left Percutaneous Nephrostomy (PCN) (Fig. 2 Inset) initially drained 800 ml of frank pus for 48 hours and then drained 1.5 to 2 litres of clear urine per day. Pus culture grew Proteus spp sensitive to Gatifloxacin. Creatinine clearance of left kidney was 60 ml/min. Patient was given Gatifloxacin dose orally for 14 days. The calculus on the vesical end of D/J stent was fragmented endoscopically using ultrasound energy and the renal stone fragmented with ESWL (800 shocks at 18 KV). Patient was simultaneously started on citrate solution orally for fragment dissolution. After a week the stent was removed endoscopically under fluoroscopic guidance to look for uncoiling of the renal end. PCN was removed after clamping for 24 hours when a Nephrostomogram revealed no obstruction. Subsequent recovery was uneventful.

Discussion

Double-J ureteral stents are commonly placed for short term (4-12 weeks) for prevention or relief of upper urinary tract obstruction and following reconstructive surgery. During this period, they may cause “stent syndrome” consisting of irritative voiding symptoms with flank pain. Complications with long term placement (3-6 months) of D/J stents are more likely to occur if the patient does not come for followup and the stent is retained or forgotten for months or years.

In such cases X-ray KUB forms the primary investigation. If there are no encrustations, then cystoscopic removal may be attempted under fluoroscopic control. Even when no surface encrustations are visible on X-ray, the lumen of such stents are filled with calcified material and this may prevent uncoiling or straightening of the renal coil and difficult removal. If patient complains of flank pain, if the stent is not moving easily or the renal coil is not straightening on fluoroscopy, the procedure should be terminated. Any forcible attempt to remove the stent can result in its fracture. A PCN should be done and stent removed through nephroscope after tract dilatation. If X-ray KUB showing encrustations on renal end, USG and IVU should be done. If USG shows moderate to gross hydronephrosis and/or pyonephrosis and IVU shows poor or non function then PCN is essential to relieve obstruction and assess kidney function. As X-ray KUB of this patient showed encrustation of less than 3 mm on renal coil of stent and a huge calculus formed on bladder coil simple cystoscopic removal was not possible. Since IVU showed nonvisualisation of left kidney and USG suggested left pyonephrosis, a PCN was done with gratifying results. ESWL was used to break the encrustations on the renal coil. If the encrustations are more than 3 mm, ESWL may fail and PCNL will be required for removal. Encrustations are usually made up of struvite² and accordingly broad spectrum antibiotic with gram negative cover is required. Bladder stones on vesical coil, however big, can be endoscopically fragmented using ultrasound, pneumatic or electrohydraulic energy and fragments washed out. The stent can then be removed by grasping in forceps under fluoroscopy guidance to monitor uncoiling of renal end. Encrustations along stent in mid-ureter are rare and may require ureteroscopic fragmentation. Open surgical exploration is the last resort in such cases.

Illiteracy among the patients, improper follow up, inadequate communication between the treating surgeon and the patient may play an important role in the aetiology of stent retention as was seen in this patient. A stent registry should be maintained by all urologist for prevention of such complications. The patient’s name, address, telephone number, date of insertion and type of stent recorded.

The patient should be made aware of the importance of stent insertion and its timely removal. A reminder letter or phone call should be made in case the patient fails to keep his or her appointment. With a careful methodical approach most patients with retained or forgotten stents can be successfully and safely managed. To avoid such complications, stent should be removed between one and three months of placement.

References

1. Somers WJ. Management of forgotten or retained indwelling ureteral stents. Urology 1996; 47 (3) : 431-35.

2. Robert M, Boularan AM, El Sandid M, Grasset D. Double-J uretric stent encrustations : clinical study on crystal formation on polyurethane stents. Urol Int 1997; 58 (2) : 100-4.

EFFICACY OF MALARIA TREATMENT SHOWS SOME DECLINE

Sulfadoxine-pyrimethamine has good therapeutic efficacy but diminishing clinical and parasitological efficacy ten years after its introduction in Malawi. Plowe and colleagues studied 1377 patients treated with sulfadoxine-pyrimethamine from 1998 to 2002 in Malawi. Although the clinical response in the first 14 days was adequate and did not change over the five years, the rates of parasite clearance declined over time. This may presage a decline in efficacy and new effective treatment may soon be required, the authors say.

BMJ, 2004; 328 : 545.