Right Ureterovesical Junction Stone: Etiology, Diagnosis, and Management

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Introduction

Urinary stones remain a significant global health concern, with ureteral calculi constituting a large proportion of emergency urological admissions. Among these, stones lodged at the ureterovesical junction (UVJ)—where the ureter meets the bladder—are of particular clinical importance due to their tendency to cause acute flank pain, urinary obstruction, and complications if left untreated.

This article provides a comprehensive expert-level review of stone in the right ureteral bladder (right UVJ stone), incorporating the etiology, pathophysiology, epidemiology, clinical presentation, imaging features, treatment, and prognosis. Reference will be made to the clinical case of a 57-year-old male presenting with acute right flank pain with associated intravenous urogram (IVU) imaging findings (Figures 1 and 2).

1. Etiology and Risk Factors

Ureteral bladder stones typically originate from the kidney and migrate down the ureter, where they may become impacted at anatomical narrowing sites. The ureterovesical junction is one of the most common impaction points due to its sharp angulation and narrow lumen.

Major etiological factors include:

  1. Metabolic abnormalities

    • Hypercalciuria, hyperoxaluria, hyperuricosuria, and cystinuria.

    • Low urine citrate, which normally prevents stone aggregation.

  2. Dietary and lifestyle contributors

    • High intake of sodium, animal proteins, and oxalate-rich foods.

    • Dehydration and low fluid intake.

    • Obesity and sedentary lifestyle.

  3. Anatomical and functional abnormalities

    • Congenital ureteral narrowing.

    • Vesicoureteral reflux.

    • Neurological bladder dysfunction leading to urinary stasis.

  4. Secondary causes

    • Chronic urinary tract infection (struvite stones).

    • Post-surgical changes in the urinary tract.

2. Pathophysiology

The formation and impaction of a right UVJ stone follows a well-described pathophysiological process:

  1. Crystal supersaturation: Urinary solutes (calcium oxalate, uric acid, cystine) exceed their solubility threshold.

  2. Nucleation and aggregation: Crystals aggregate and form a nidus.

  3. Migration: Stones formed in the kidney pass through the ureter.

  4. Impingement at UVJ: Due to the narrow anatomical structure, stones often lodge at the UVJ.

  5. Obstruction and hydronephrosis: Obstructed urine flow leads to proximal ureteral and renal pelvic dilation, increased intrarenal pressure, and ischemia.

  6. Pain generation: Distension of the renal capsule and ureter stimulates nociceptive fibers, producing acute colicky flank pain.

3. Epidemiology

  • Prevalence: Kidney and ureteral stones affect approximately 12% of the global population, with men more frequently affected than women (2–3:1 ratio).

  • Age distribution: Peak incidence occurs between 30 and 60 years, consistent with the 57-year-old male in our case.

  • Geographical variations: Higher incidence in “stone belt” regions such as the Middle East, Southeast Asia, and parts of the United States, linked to climate, diet, and genetic predisposition.

  • Recurrence rates: Up to 50% recurrence within 10 years, emphasizing the importance of preventive strategies.

4. Clinical Presentation

The 57-year-old male patient presented with a sudden onset of right flank pain, a hallmark feature of ureteral stones.

Typical symptoms include:

  • Renal colic: Severe, colicky pain radiating from the flank to the groin.

  • Lower urinary tract symptoms: Frequency, urgency, dysuria (when the stone is near the bladder).

  • Hematuria: Microscopic or gross blood in urine due to mucosal irritation.

  • Nausea and vomiting: Due to vagal stimulation.

  • Restlessness: Unlike peritonitis, patients with renal colic often cannot remain still.

Physical examination findings:

  • Costovertebral angle tenderness (right-sided in this case).

  • Normal abdominal signs unless complicated by infection.

5. Imaging Features

Figure 1. Intravenous urogram at 12 minutes post-contrast injection showing a right UVJ stone with ureteral dilation.

[Figure 1] shows an IVU image taken 12 minutes after contrast injection, revealing:

  • Dilated right ureter with absence of peristaltic activity.

  • Filling defect at the right UVJ, consistent with a stone.

  • Periureteral edema.

Figure 2. Intravenous urogram images (A: 3 minutes, B: 12 minutes) showing delayed right renal excretion, right pelvic stone, and UVJ obstruction.

[Figure 2A] (3 minutes):

  • Normal excretion from the left kidney.

  • The right pelvic calculus is visible.

  • Delayed contrast excretion on the right side.

[Figure 2B] (12 minutes):

  • Hydronephrosis of the right renal pelvis.

  • Dilated ureter leading to the bladder.

  • Periureteral filling defect indicating obstruction.

6. Differential Diagnosis

Conditions that mimic right UVJ stones include:

  • Ureteral stricture

  • Blood clot

  • Urothelial carcinoma

  • Extrinsic compression (e.g., pelvic tumor, retroperitoneal fibrosis)

7. Treatment

Management depends on stone size, location, and patient condition.

7.1 Conservative Management

  • Indicated for stones <5 mm, as most pass spontaneously.

  • Hydration, analgesics (NSAIDs, opioids if severe).

  • Alpha-blockers (e.g., tamsulosin) to facilitate stone passage.

7.2 Active Intervention

  • Extracorporeal Shock Wave Lithotripsy (ESWL): Non-invasive; effective for stones <2 cm.

  • Ureteroscopy with laser lithotripsy: Gold standard for UVJ stones; allows direct fragmentation and retrieval.

  • Percutaneous nephrolithotomy (PCNL): Reserved for larger, complex stones.

  • Open or laparoscopic surgery: Rare, only if minimally invasive approaches fail.

8. Prognosis

  • Excellent with prompt treatment. Most UVJ stones resolve without long-term sequelae if managed early.

  • Complications if untreated:

    • Hydronephrosis and loss of renal function.

    • Urinary tract infections progressing to pyelonephritis or sepsis.

    • Chronic kidney disease.

9. Case Summary

A 57-year-old male presented with acute right flank pain. Imaging confirmed a stone at the right ureterovesical junction, with hydronephrosis evident on delayed IVU. This case illustrates the classic pathophysiological process and radiological hallmarks of a UVJ stone.

Quiz

Q1. What is the most common site of ureteral stone impaction?

(A) Upper ureter

(B) Mid-ureter

(C) Ureterovesical junction

(D) Ureteropelvic junction

Q2. Which imaging feature suggests a right UVJ stone on IVU?

(A) Early excretion of contrast on both sides

(B) Left-sided hydronephrosis

(C) Filling defect at the right ureterovesical junction with delayed right renal excretion

(D) Dilated left ureter

Q3. Which treatment is most effective for a 1 cm stone at the right UVJ that fails to pass spontaneously?

(A) Conservative hydration only

(B) Extracorporeal shock wave lithotripsy (ESWL)

(C) Ureteroscopy with laser lithotripsy

(D) Open nephrectomy

Answer & Explanation

1. Answer: (C) Ureterovesical junction. Explanation: The UVJ is the narrowest part of the ureter, making it the most common site for stone impaction.

2. Answer: (C) Filling defect at the right ureterovesical junction with delayed right renal excretion. Explanation: Classic IVU features include obstruction, hydronephrosis, and delayed excretion on the affected side.

3. Answer: (C) Ureteroscopy with laser lithotripsy. Explanation: URS with laser lithotripsy is the gold standard for symptomatic UVJ stones >5 mm that do not pass spontaneously.

References

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