High-volume Concurrent Polypoid Ureteritis and Ureteritis Cystica Manifesting With Ureteral Obstruction

Polypoid ureteritis, or fibroepithelial ureteral polyps, are a rare but benign neoplasm of unknown etiology in the upper urinary tract and may occur at any age.¹ Ureteritis cystica is also a rare but benign phenomenon that may develop following inflammatory conditions of the ureter and/or renal pelvis.¹ Due to their appearance on imaging and frequently accompanying symptoms of gross hematuria, the masses are often clinically indistinguishable from upper tract urothelial carcinoma (UTUC) in adults.² Children may manifest with signs and symptoms of ureteropelvic junction obstruction.³ Complete resection is often necessary for symptom relief and to definitively address partial or complete upper urinary tract obstruction.

We present a case of a middle-aged female incidentally found to have a partially obstructing left midureteral mass and prominent regional lymph node on imaging workup of a nonurologic diagnosis. Ureteroscopic evaluation and biopsy revealed simultaneous polypoid ureteritis and surrounding ureteritis cystica. Subsequent staged, endoscopic holmium laser ablation was performed to definitively address her resultant hydroureteronephrosis.

CASE PRESENTATION

A 67-year-old white female with no significant past medical history was admitted to the hospital for new onset jaundice. Her symptoms consisted of yellow skin and conjunctiva, diffuse pruritus, and elevated hepatic enzymes. As a part of her workup, she underwent a contrasted computed tomography scan that incidentally demonstrated a roughly 5 cm left midureteral mass with frond-like intraluminal projections, proximal ureteral dilation, and a paraaortic 1.1 cm lymph node with high concern for regionally advanced UTUC (Fig. 1). She was not experiencing any flank pain or gross hematuria. Beyond elevated liver function tests, her laboratory workup was unremarkable. She had a creatinine of 0.8 mg/dL, a normal estimated glomerular filtration rate, no microscopic hematuria, and a negative urine culture. On further interrogation, she did not have any past urologic history such as urolithiasis, recurrent urinary tract infections, or prior urologic instrumentation. She never smoked or experienced chemical exposure, was a retired school teacher, and did not have any ties to geographic regions with associated endemic nephropathy.

Figure 1.

Coronal CT scan with intravenous contrast of the abdomen and pelvis. (A) Arterial phase (B) delayed urogram. CT, computed tomography.

Her acute jaundice was ultimately attributed to an azithromycin-related, drug-induced liver injury that resolved with conservative management. She was discharged from the hospital 3 days following her admission with plans for a confirmatory diagnostic workup of her ureteral mass once her hepatic function fully recovered.

Three weeks later, she was taken to the operating room for cystoscopy, left ureteral barbotage, retrograde pyelogram, and a diagnostic ureteroscopy. Her retrograde pyelogram redemonstrated the midureteral intraluminal appearing mass with associated proximal hydroureteronephrosis (Fig. 2). Semirigid ureteroscopy revealed numerous intraluminally projecting rounded, tan-colored, pedunculated masses (Fig. 3). The ureteroscope could be advanced proximally to these lesions allowing appreciation of her proximally dilated ureteral lumen with normal mucosa. A repeat retrograde pyelogram through the semirigid ureteroscope did not demonstrate any additional filling defects in the proximal ureter or renal collecting system. Numerous biopsies were then obtained using a transureteroscopic biopsy forceps and a basket device. An indwelling double-J ureteral stent was left in place and she was discharged home on the same day.

Figure 2.

Left retrograde pyelogram redemonstrating a midureteral filling defect and proximally dilated system. Several air-bubbles were present in the proximal ureter.

Figure 3.

Appearance of ureteral fibroepithelial polyps and smaller ureteritis cystica lesions on (A) initial semirigid ureteroscopy and (B) subsequent holmium laser ablation.

Gross and microscopic pathologic analysis revealed polypoid ureteritis with marked ureteritis cystica. To alleviate her visualized proximal obstruction, she was taken back to the operating room for a second staged ureteroscopic procedure to perform complete ablation of these benign lesions using a holmium laser and double-J stent replacement to allow scaffolded healing of the ablated ureteral lumen (Fig. 3). She was again discharged home the same day without incident. Her stent was uneventfully removed 4 weeks later in the office.

DISCUSSION BY SOROUSH RAIS-BAHRAMI, MD

Benign ureteral tumors are seldom encountered. Fibroepithelial ureteral polyps were first described in 1932 with only several hundred cases reported to date.^4,5 Ureteritis cystica was first characterized by Morgagni the mid-18th century by their appearance of suburothelial cysts with fingerlike projections into the ureteral lumen.^1,6,7 Due to the rarity of both lesions, proposed etiologies and incidence for both are quite variable in the literature.^3,8–11

In children, ureteral polyps are thought to be congenital in origin and primarily occur in the proximal third of the ureter and renal pelvis.^7,12,13 They are seldom detected in utero presumably due to their indolent growth pattern, and instead manifest during early childhood. Symptoms and signs are similar to those of ureteropelvic junction obstruction caused by more common etiologies such as flank pain, recurrent infection, hematuria, and/or hydronephrosis.³ For unclear reasons, the left ureter is more commonly affected than the right, with a reported 2:1 left:right predominance.¹⁴ Following discovery on imaging and confirmatory diagnosis via retrograde pyelogram or ureteroscopy, complete excision for symptom relief and treatment of proximal obstruction can be achieved with a dismembered pyeloplasty.^3,15,16 Alternatively, successful endoscopic resection has been reported.^5,17 Ureteritis cystica is less commonly reported in the pediatric urology literature.

Ureteral polyps in adults typically present in the third or fourth decades of life with a reported male predominance.^1,18 Individual polyp size can span anywhere from 5 mm-12 cm in size.¹ While pediatric ureteral polyps are thought to be congenital in origin, the etiology is less clear in adult patients. Chronic inflammatory states such as infection, Schistosomiasis, prior trauma, and/or instrumentation may promote their development.^9,19 They may also develop in the absence of a known cause. In 1 retrospective series by Childs et al, 9/22 (41%) of patients with histologically confirmed benign ureteral polyps had no prior urologic history and were presumed to have developed the tumors idiopathically. Ureteritis cystica may also form in adults following a previous inflammatory condition involving urothelial mucosa such as urolithiasis, infection, or prior endoscopic instrumentation.^1,11,20 Presenting symptoms of both conditions are similar to those experienced by children, but some adults may be asymptomatic and they are instead discovered incidentally when abdominal imaging is performed for a nonurologic indication.²¹

On imaging, ureteral polyps and ureteritis cystica may be detected secondary to ureteral obstruction or an apparent intraluminal mass. On contrast-enhanced computed tomography, ureteral polyps and ureteritis cystica appear as an intermediate density mass within the ureter that may result in hydroureteronephrosis. On delayed excretory phase imaging with excreted iodinated contrast in the ureter, they can manifest as multiple intraluminal filling defects with a frond-like appearance, analogous to their appearance on retrograde pyelogram. Currently, little data exist about the appearance of ureteritis cystica on magnetic resonance imaging due to the rarity of this entity. Given the appearance of ureteral polyps and ureteritis cystica on imaging along with frequently accompanying hematuria, adult patients are initially managed with suspicion that the mass represents urothelial carcinoma of the ureter. In the contemporary setting, patients then undergo ureteroscopic evaluation and transureteroscopic biopsy for pathologic confirmation.²² Due to the sometimes difficult nature of upper tract instrumentation, cytology and inadequate tissue acquired via biopsy, a definitive diagnosis of polypoid ureteritis and/or ureteritis cystica may only be available after radical nephroureterectomy.^2,23,24

Gross pathologic examination of fibroepithelial ureteral polyps reveals a tan or brown smooth surface with round intraluminal projections. Microscopically, the polyps exhibit a normal urothelial mucosal surface with a loose fibrovascular stroma underneath. Ureteritis cystica similarly has a normal urothelial mucosa but with cystically dilated urothelial cysts, known as van Brunn nests, embedded below their mucosal lining. Both differ from the grossly apparent papillary projections, microscopic nuclear pleomorphism, and stromal infiltration evident in UTUC.¹ The incidence of concurrent ureteral polyps and ureteritis cystica is not known but estimated to be exceedingly rare with only a few previously reported cases.²¹

Management of both polypoid ureteritis and ureteritis cystica is aimed at relief of symptoms as well as alleviation of proximal ureteral obstruction to optimally preserve renal function. Ureteroscopic resection with loop electrocautery or laser ablation is safe and well-tolerated with acceptable outcome in affected patients.^1,7,8,10 Alternative endoscopic treatment modalities for obstructed patients include balloon dilation, silver nitrate instillation, or long-term antibiotic therapy with varying long-term success.^8,11 In an asymptomatic individual without evidence of obstruction, intervention may not be necessary at all.^8,11 Radical nephroureterectomy or segmental ureterectomy are not indicated unless suspicion for UTUC remains following a thorough diagnostic workup and tissue sampling.²

The role of long-term surveillance after definitive resection or ablative therapy is unclear. Association of polypoid ureteritis and ureteritis cystica with urothelial carcinoma or other malignant processes is very uncommon with only a few rare cases reported.^1,5,8,25 Imaging and/or ureteroscopic surveillance may benefit patients with a large tumor burden on initial presentation who may be at risk for symptomatic recurrence. In those instances, repeat resection or ablation procedures can be performed.⁵ Postoperative ureteral stricture formation is another potential complication with an incidence similar to that of other endoscopic procedures for manipulation of upper tract tumors, and may require additional procedures to address the stricture to maintain patency of the ureter.^5,10,26

In the present case, the etiologies both fibroepithelial ureteral polyp and ureteritis cystica formation are unclear. They may have occurred idiopathically, the polyps could have propagated secondary ureteritis cystica formation by causing inflammatory changes to nearby urothelium over time. Periodic imaging surveillance with ultrasonography is planned to ensure hydroureteronephrosis does not recur.

CONCLUSION

Ureteral fibroepithelial polyps and ureteritis cystica are two distinct, benign and rare conditions of the upper urinary tract with an incredibly low malignant association though recognized as clinical mimickers of UTUC. Underlying etiologies of both processes are unclear, and patients may present with quite varying symptomatology. Following confirmatory diagnostic workup, endoscopic resection or ablation provides symptom relief and alleviates obstruction of the affected renal moiety.