Introduction

Modern endourology has allowed surgeons to treat stones in complex situations that would previously require a major intervention. While less invasive treatment for complex stones provides faster recovery, some cases pose complex challenges. The complexity may result from stone burden and location, patient comorbidities, anatomical characteristics, or a combination thereof. Herein we describe the diagnosis, management, and follow-up of a patient with a right ureteric stone in the context of a massive paraperitoneal ureteroinguinal hernia (UIH).

Case Presentation

A 76-year-old man with a medical history significant for hypertension, type 2 diabetes, neurogenic bladder, and a right inguinal hernia was transferred with a 12-mm ureteric stone, chills, and subjective fever. Investigations revealed a marginally elevated creatinine (150 μmol/L) and leukocytosis (22.1 × 10⁹/L). CT scan showed a low-lying right kidney with perinephric fat stranding and a 12-mm ureteric stone with moderate proximal hydronephrosis. Noteworthy, part of the ureter was herniated within a large right indirect inguinal hernia (Figure 1, A-F).

Management

The patient was started on broad-spectrum antibiotics, and urinary decompression was indicated and achieved with a right US-guided nephrostomy tube insertion. The patient stabilized clinically and was discharged well from the hospital.

A shared decision for ureteroscopy and laser lithotripsy was made for definitive stone treatment. At the time of cystoscopy, we were unable to identify the right ureteric orifice, and therefore a guidewire was advanced in an antegrade fashion through the nephrostomy tube to the level of the bladder. The guidewire was extracted from the bladder with endoscopic graspers securing through-and-through access. Interestingly, fluoroscopy showed the ureter made 2 complete loops outside the bladder and into the hernia, as documented on retrograde pyelogram (Figure 2, A and B). Following dilation of the ureteral orifice, a digital flexible ureteroscope was backloaded over the guidewire and advanced to the level of the stone, which was then effectively fragmented with the holmium:YAG laser. A 30-cm × 7F double-J stent was placed (Figure 2, C) and the nephrotomy tube removed.

Figure 3. X-ray of kidney-ureter-bladder showing no residual fragments and the proximally migrated double-J ureteric stent along the course of the ureter in the ureteroinguinal hernia.

An x-ray of the kidney-ureter-bladder showed no residual fragments in follow-up, but the ureteric stent had migrated proximally and was not visible at the time of cystoscopy (Figure 3). The migrated stent was removed percutaneously by intervention radiology. Follow-up US showed improvement of the hydroureteronephrosis, and the patient was discharged from urology and referred to general surgery for hernia repair.

Discussion

Inguinal hernias can be classified as direct if they protrude through Hesselbach’s triangle or otherwise as indirect. Ureter-containing hernias are rare and can be found on inguinal or femoral defects. UIHs are a unique type of indirect inguinal hernia and can be further divided as paraperitoneal and extraperitoneal. The former is the most common type (∼80%) and contains a peritoneal evagination, whereas the latter contains ureter only and might additionally contain some retroperitoneal fat.^1-3

As paraperitoneal UIH develops a peritoneal sac, other abdominal viscera may be contained within. Thus, the ureter is pulled down into the inguinal canal along the hernia, attached to the hernia sac wall by an unusual adherent layer of posterior parietal peritoneum. As the ureter is a retroperitoneal structure, it is not truly within the peritoneal sac. The extraperitoneal UIH, on the other hand, lacks a peritoneal sac and the ureter protrudes solo along some retroperitoneal fat. The bladder is frequently herniated as well in one-quarter of patients. This type of UIH is mostly associated with urinary tract anomalies as ptosis of the kidney or after kidney transplant. The underlying mechanisms are not fully understood, but a congenital basis has been suggested in which the ureteric bud fails to separate from the Wolffian duct. Both the bud and the Wolffian duct are drawn down to the scrotum to form the epididymis and vas deferens.^2-5

UIHs are mostly underdiagnosed until unexpectedly encountered during surgery, thus carrying a risk of ureteric injury. UIH can be asymptomatic, but otherwise may be diagnosed when associated with other conditions such a stone causing obstruction and/or urinary tract infections, hydroureteronephrosis, acute kidney injury, and lower urinary tract symptoms. A CT urogram is paramount for the diagnosis of UIH and associated conditions such as stones. Moreover, CT allows adequate surgical planning. If renal impairment is encountered, magnetic resonance imaging is a good alternative choice.^3,4

When urgent decompression is needed in the context of complex stone associated with a UIH, nephrostomy drainage is recommended given challenges that may be anticipated with retrograde stent insertion. In our case, the nephrostomy access also assisted in securing a guidewire to facilitate ureteroscopy. It is also recommended to perform a retrograde or antegrade pyelogram to understand the anatomy and trajectory of the ureter, and this may be facilitated by having a nephrostomy tube in. In fact, the “curlicue” or “loop the loop” sign is pathognomonic of UIH (Figure 2, A). This sign comprises the loops of the ureter vertically oriented and is seen in ureterofemoral hernias and UIHs, as opposed to more horizontally oriented loops, which are seen in ureterosciatic hernias.⁶

Conclusion

UIHs with urinary stones are exceedingly rare. Despite being a rare situation, it is important to bear in mind that, in a patient with hydronephrosis and an ipsilateral inguinal hernia, UIH is a possible diagnosis and important to anticipate in cases where hernia repair is contemplated. Moreover, endourological management of patients with stones in the context of UIHs is feasible yet challenging, and surgeons must mind the risk of stent migration as ureteral length is typically enhanced. Nephrostomy tube placement facilitates the treatment for both retrograde and antegrade approaches.