Therapy-Resistant Nephrolithiasis Following Renal Artery Coil Embolization

Cédric Poyet; Florian Grubhofer; Matthias Zimmermann; Tullio Sulser; Thomas Hermanns


BMC Urol. 2013;13(29) 

In This Article

Case Presentation

A 22 year-old woman with a lumbal meningomyelocele presented to our center with bilateral staghorn calculi. The patient was known for her atonic neurogenic bladder and she performed intermittent self-catherization for many years. She suffered from recurrent urinary tract infections with repeated episodes of right-sided pyelonephritis. Due to considerable skeletal deformities the patient was considered uneligible for a percutaneous nephrolithotomy. Therefore, bilateral open pyelolithotomy was performed. It was possible to remove the stones completely without any intra-operative complications. For an unknown reason, a stone analysis was not performed after the operation. Eight days after surgery persistent gross haematuria occurred. Renal angiography demonstrated active bleeding from a left lower-pole interlobular renal artery. During renal angiography RAE was performed using three fibered platinum microcoils (2 mm circle diameter, Boston Scientific Corporation, Watertown, USA). After initial cessation of the bleeding, the patient presented two weeks later with recurrent hematuria and a second RAE procedure of the same interlobular renal artery was performed. Three additional microcoils were placed, and bleeding was controlled. No further hemorrhage occurred.

Four years later, the patient presented again with recurrent right-sided pyelonephritis. Following antibiotic treatment asymptomatic leukocyturia and erythrocyturia persisted. These were attributed to the intermittent self-catherization. Although significant growth of Escherichia coli was repetitively detectable in the urine culture, the patient was only treated when she was symptomatic.

An abdominal computed tomography (CT) showed an atrophic kidney on the right side and a solitary 15.4 mm stone in the lower renal calyx. The stone was located adjacent to the coiling material placed four years earlier (Figure 1). A radionuclide MAG3 differential renal scan confirmed the diagnosis of an inactive kidney on the right side.

Figure 1.

The pre-operative CT-scan revealed a 15.4 mm stone in the lower calix of the left kidney. Metal wires in the renal parenchyma were adjacent to the stone. Coiling material in the collecting system or within the stone was not identified.

Primarily, an open right-sided nephrectomy was performed. The post-operative course was uneventful and the patient was discharged five days after surgery. Symptomatic urinary infections did not occur anymore after the nephrectomy.

Three months after the nephrectomy, an extracorporeal shock wave lithotripsy (ESWL) was performed to treat the stone in the left kidney using an electromagnetic Dornier DL50 lithotrypter (Dornier MedTech, Wessling, Germany). A total of 3000 shock waves (16 kV, positive energy of the 5-mm focal area E + 5 mm: 10.1 mJ) were applied. A ureteral stent was inserted to prevent obstructive complications of the left solitary kidney. Follow-up investigations revealed insufficient disintegration of the stone. Thus, two months after the initial treatment, a second ESWL was performed. Six weeks after this ESWL, stone disintegration was still not detectable (Figure 2).

Figure 2.

Plain abdominal film showing the stone after the second ESWL treatment. The close vicinity of the stone and the coiling material can also be seen.

Subsequently, a flexible ureterorenoscopy (f-URS) was performed. Intra-operatively the solitary stone in the lower calyx was identified. However, the stone was adherent to intraluminal metal coil wires (Figure 3). These metal wires were partly located in the lower calyx and partly in the renal parenchyma. The intraluminal wires were densely integrated into the stone. Despite the two precedent ESWL treatments, the stone appeared almost unaffected. The stone was disintegrated using the holmium laser and removed from the coiling material. The remaining intraluminal coil wires were cut off with the laser at the parenchymal border. Subsequently, the wires and all stone fragments were removed using a dormia basket. At the end of the procedure the renal pelvis was free of stones and coiling material. A ureteral stent was inserted.

Figure 3.

Endoscopic view during f-URS. The dislocated coiling material is incorporated into the lower-pole kidney stone.

After an uneventful peri-operative course, the patient was discharged at the first post-operative day. The ureteral stent was removed two weeks later. X-ray diffraction stone analysis revealed a stone composition of 60% calciumoxalate-monohydrate and 40% apatite. Six months after the procedure, the patient remained stone free as assessed by abdominal ultrasound and plain abdominal film.