Concomitant occurrence of pyelocalyceal diverticulum and ipsilateral large sized orthotopic ureterocele in an adult: a rare association

Abstract

Pyelocalyceal diverticulum is an incidental finding detected on routine ultrasonography scans which may also show symptoms of recurrent urinary tract infections secondary to urinary stasis and calculi formation within the diverticulum. Orthotopic type of ureterocele occurs as an isolated abnormality and is mostly confined to adults as opposed to ectopic type of ureterocele which is congenital in origin and commonly seen in children and is almost always associated with a duplicated collecting system. We report a case of concomitant occurrence of pyelocalyceal diverticulum and ipsilateral large sized orthotopic ureterocele diagnosed on high-resolution ultrasonography and confirmed on contrast enhanced computed tomography in a 54-year-old adult female. The patient underwent resection of the ureterocele with insertion of left sided double-J ureteral stent which was left in place for 4 weeks following which the patient’s symptoms improved and she was discharged after an uneventful post-operative recovery period.

Introduction

Although there are numerous case reports describing pyelocalyceal diverticulum [1] and ureterocele [2] as separate entities exist in literature, a combination of both these entities is a rare occurrence. A single case report has emerged during literature review which describes a case of left ureterocele and a calculus within the calyceal diverticulum in patient with bilateral duplex kidneys [3]. The current case report deserves a special mention as it describes concomitant occurrence of pyelocalyceal diverticulum and ipsilateral large sized orthotopic ureterocele in an adult patient with no ureteric duplication. The association described in this case report on a 54-year-old adult female may be a first of its kind in literature.

Case report

A 54-year-old woman presented to the urology department with complaints of recurrent episodes of burning micturition and suprapubic tenderness in the past 6 months. She gave no history of fever, hematuria or flank pain. The patient reports to have passed urine at intervals of 3–4 h and she woke up more than once at night to micturate. The patient has been experiencing these urinary complaints since 6 months. Past history was negative for hypertension and diabetes mellitus. There was also no significant family history. General physical examination revealed that her vitals were normal and the patient was not in distress. On clinical examination the patient was afebrile and had no renal angle tenderness on either side. Normal bowel sounds were audible. The patient was referred for ultrasonography of the kidneys and urinary bladder (KUB) which revealed a cystic lesion measuring 2.8 × 3.2 cm in the superior pole of left kidney showing communication with the upper pole major calyx and the renal pelvis. There was associated mild hydronephrosis involving rest of the left kidney (Fig. 1a). There was no evidence of nephrolithiasis, pyelonephritis or ureteral duplication on ultrasonography. Urinary bladder showed multiple internal echoes consistent with active urinary tract infection. Furthermore, there was evidence of a cystic lesion measuring 4 × 3 cm projecting into the bladder lumen at the site of left vesicoureteric junction (VUJ) (Fig. 1b). Based on ultrasonography findings, a differential diagnosis of pyelocalyceal diverticulum and an incomplete duplication of the left kidney, with an associated ipsilateral orthotopic ureterocele were considered. (Fig. 2) Contrast enhanced computed tomography in the delayed phase confirmed with certainty the diagnosis of a pyelocalyceal diverticulum pertaining to the left kidney and a left-sided ureterocele with no evidence of duplex collecting system (Figs. 3, 4). Subsequently the patient was referred back to the urology department for further management. Laboratory investigations revealed a hemoglobin level of 11g/dL, leukocytosis of 19 × 10⁹/L (neutrophils 90%) with positive leukocyte esterase and nitrite, blood urea nitrogen of 20 mg/dL and creatinine of 1.5 mg/dL which indicated mild renal insufficiency. Her urine analysis with microscopy was positive for pyuria ++ (WBCs/HPF: 15–20), urinary sludge +++ and bacteriuria ++. Urine culture grew Escherichia coli (>10⁵ colonies/ml) which was sensitive to previous antibiotics. Foley catheterization was done and 480 ml of turbid urine was drained instantly. The patient was started on a combination of piperacillin–tazobactam and intravenous crystalloids for the management of her current episode of cystitis. After completion of the antibiotic course and having a negative bacterial culture, surgical management for the ureterocele was planned. Cystoscopy was performed which demonstrated a 4 × 3 cm left ureterocele. A ureteral orifice was apparent. A guidewire was able to pass retrograde into the ureter. There was no decompensated urinary bladder. There was no evidence of ureteral ectopia. Transurethral resection of ureterocele, bleeding point hemostasis, and biopsy of the resected specimen was performed. The patient was put in lithotomy position and a 22-F cystoscope was introduced into the urinary bladder. A large left-sided intravesical ureterocele protruding into the lumen of the urinary bladder with a relatively small ureteric orifice was identified on cystoscopy. In addition, a normal right-sided ureteric orifice was identified. Furthermore, a 24-F resectoscope was inserted and deroofing of the left-sided ureterocele was performed with cutting current of diathermy. Following surgery, a 20-F Foley catheter was inserted and irrigation of the urinary bladder was initiated. The surgical procedure was performed without complications and the post-operative period was uneventful. Patient remained on urinary bladder catheter for 72 h following the procedure and evolved without hematuria. Following ureterocele resection, the patient underwent insertion of left sided double-J ureteral stent which was left in place for 4 weeks following which the patient’s symptoms improved. She was advised for serial monitoring of renal function with periodic evaluation of voiding symptoms. Interval ultrasound was advised to assess hydroureteronephrosis and vesicoureteral reflux, if any. She was successfully managed and was discharged home after an uneventful post-operative recovery period. The biopsy specimen demonstrated urothelial mucosa fragments without atypia which was compatible with the resected ureterocele (Fig. 5). A true diverticulum lined by transitional epithelium (with muscularis) has been implicated based on findings at histopathology with no signs of dysplasia or malignancy (Fig. 6). At follow-up, 1 month and 6 months following surgery, the patient had recovered well with no urological complaints. At 1 and 6 month follow-up, urine analysis was repeated which revealed normal findings on urine microscopy (WBCs/HPF: 0–5), and samples were negative for bacterial cultures.

Fig. 1.

a Longitudinal ultrasonography image demonstrating a cystic lesion (star) with well demarcated margins (green arrows) located in the superior pole of left kidney showing communication by a fine channel (straight line) with major calyx of upper pole (blue arrow) consistent with features of pyelocalyceal diverticulum. b Longitudinal ultrasonography image demonstrating a cystic lesion (star) projecting into the bladder lumen at the site of left vesicoureteric junction consistent with features of an orthotopic ureterocele

Fig. 2.

Schematic diagram showing left pyelocalyceal diverticulum (yellow arrows) associated with left ureterocele (star). Note the length of the diverticular neck (blue arrows)

Fig. 3.

Coronal reformatted contrast enhanced computed tomography image in the delayed phase demonstrating a contrast filled cystic structure pertaining to the superior pole of left kidney consistent with features of pyelocalyceal diverticulum (arrows)

Fig. 4.

Axial contrast enhanced computed tomography image demonstrating left ureterocele (arrow). Note the dilated left distal ureter (star)

Fig. 5.

Gross specimen of the resected large left-sided ureterocele

Fig. 6.

Histopathology image of the resected ureterocele specimen demonstrating normal urothelial tissue with no nuclear atypia (H and E, ×400)

The patient has given written informed consent to publish her case and clinical images.

Discussion

Pyelocalyceal diverticulum is a congenital lesion that originates due to failure of regression of third or fourth generation ureteric buds which results in formation of outpouchings that project into the renal cortex from the renal pelvis and calyces (major and minor). Pyelocalyceal diverticulum is lined by transitional epithelium. The above condition is common in females with majority of cases being asymptomatic and diagnosed incidentally on imaging for nephrolithiasis. Symptoms range from hematuria, flank pain and recurrent urinary tract infections. Complications include calculus formation within the pyelocalyceal diverticulum and rarely transitional cell carcinoma [4].

Ureterocele is a congenital lesion that originates secondarily on failure of regression of Chwalla membrane between the developing ureteric bud and urogenital sinus which results in congenital dilatation of the terminal end of the ureter, which projects into the lumen of the urinary bladder also secondary to abnormal vesicoureteric junction. It is more common in females with majority of them found in association with duplicated collection systems. Most of these congenital ureteroceles found in children have ectopic insertion of the ureter. However, orthotopic ureteroceles which occur at the site of normal vesicoureteric junction are relatively rare and are usually found in adults as described in this case report. Symptoms are related to the reflux of urine resulting in recurrent urinary tract infections. Complications include calculi formation and progression to obstructive cystic renal dysplasia [5].

Duplication of the collecting system refers to an anatomical variant and congenital malformation with two separate pelvicalyceal systems with an incidence of 1–3%. [6] Complications of duplex collecting system are related to upper urinary tract obstruction, calculi formation and recurrent urinary tract infections. Lower moiety related complications of the duplex collecting system are related to abnormal lateral insertion of the ureteric orifice into the urinary bladder, renal scarring and vesicoureteric reflux (VUR). While ureteropelvic junction obstruction (UPJO) in lower moiety of duplex kidney is rare, VUR remains the most prevalent complication causing repeated urinary tract infections and permanent renal impairment due to renal scarring. Upper moiety related complications of the duplex collecting system are related to ectopic ureteroceles and multicystic dysplastic upper moiety kidney, though urinary tract obstruction secondary to ureterocele remains the most prevalent complication. A minority of female patients also experience urinary incontinence when the insertion of the ureteric orifice is located below the urethral sphincter.

The pathophysiology of ureterocele development has been linked to incomplete smooth muscle development of the intramural ureter leading to excessive dilatation of the intramural ureter during the embryonic development of the bladder trigone. We hypothesize that incomplete motor activity from the walls of the intramural ureter at the site of ureterocele has led to urinary stasis, proximal hydroureteronephrosis and recurrent urinary tract infections. While failure of regression of the third- and fourth-generation ureteric buds during embryogenesis has been implicated as a cause for the development of pyelocalyceal diverticulum which is connected by means of a fine channel with the calyceal fornix. We hypothesize that secondary inflammatory processes related to recurrent ascending urinary tract infections may have caused focal pyelonephritis; and subsequent healing by fibrosis may have caused successive narrowing of the communicating channel with the calyx and has led to the formation of pyelocalyceal diverticulum. Furthermore, lack of motor activity along the wall of the diverticulum may have caused urinary stasis, sludge deposition resulting in symptoms of obstructive uropathy.

Ultrasonography is the initial imaging investigation for evaluation of pyelocalyceal diverticulum, duplex renal collecting system and related complications. It may also be used as a preoperative diagnostic modality in resource starved settings. Nonetheless, for confirmation of diagnosis, intravenous pyelography (IVP) and computed tomography (CT) are routinely used because of their higher sensitivity than ultrasonography [7].

Conclusions

This case report describes the rare association of pyelocalyceal diverticulum and ipsilateral large sized ureterocele diagnosed on ultrasonography in an adult with no duplex renal collecting system and, stresses on the fact that this rare clinical entity needs to be included in the differential diagnosis in patients with recurrent urinary tract infections. In conclusion, this case report is unique as ureteric duplication can assume similar configuration with ectopic ureterocele related urinary tract obstruction developing as the most frequent upper moiety related complication in such patients.

Funding

Nil.

Declarations

Conflict of interest

The authors declare that they have no conflict of interest.

Patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form, the patients have given their consent for their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.