Will an 8.8‑mm stone in the proximal left ureter pass spontaneously?

Will an 8.8 mm Proximal Left Ureteral Stone Pass Spontaneously?

No, an 8.8 mm stone in the proximal ureter is highly unlikely to pass spontaneously and requires ureteroscopic intervention. 1

Evidence for Spontaneous Passage Rates

The likelihood of spontaneous passage drops dramatically as stone size increases beyond 5 mm:

• Stones 5 mm: 65% passage rate in 20 weeks 2
• Stones 6 mm: 33% passage rate in 20 weeks 2
• Stones ≥6.5 mm: Only 9% passage rate in 20 weeks 2

For stones in the 4–6 mm range, 95% of those that will pass do so within 39 days, but intervention is required in approximately 50% of stones greater than 5 mm 3. Your 8.8 mm stone falls well above this threshold, making spontaneous passage extremely improbable.

Location-Specific Considerations

Proximal ureteral stones face additional barriers to passage 4:

• At emergency presentation, only 10.6% of stones lodge at the ureteropelvic junction, while 23.4% are found between the UPJ and iliac vessels 4
• Proximal stones are significantly larger than distal stones (mean 6.1 mm vs 4.0 mm axial diameter) 4
• The proximal ureter's anatomy makes spontaneous passage of large stones particularly unlikely 1

Recommended Management: Ureteroscopy

Ureteroscopy is the definitive first-line treatment for your 8.8 mm proximal ureteral stone 1, 5:

• Stone-free rate: 81–93% for proximal ureteral stones of any size in a single procedure 1
• Flexible ureteroscopy achieves superior results (87% stone-free) compared to rigid ureteroscopy (77%) for proximal stones 1
• The 2007 AUA guidelines explicitly state that ureteroscopy is appropriate for stones of any size in the proximal ureter, expanding beyond the older ≥10 mm threshold 1

Why Not Medical Expulsive Therapy?

Medical expulsive therapy (MET) with alpha-blockers is not recommended for your stone 6:

• MET provides a 29% absolute increase in passage rates for distal ureteral stones 5–10 mm 6
• Your stone is proximal (not distal) and 8.8 mm (near the upper size limit)
• The maximum observation period is 4–6 weeks to prevent irreversible kidney damage 6, 5
• Given the <10% spontaneous passage likelihood, attempting MET would waste 4–6 weeks with minimal chance of success 2

Alternative: Shock Wave Lithotripsy

Shock wave lithotripsy (SWL) is a less effective alternative for your stone 1, 5:

• Stone-free rate: 73–87% for proximal stones <10 mm (lower than URS) 1, 5
• For stones approaching 9 mm, ureteroscopy demonstrates clear superiority over SWL 5
• SWL may require multiple sessions, whereas URS typically achieves stone clearance in one procedure 1

Critical Pitfalls to Avoid

• Do not pursue prolonged conservative management beyond 4–6 weeks—this risks irreversible renal damage from chronic obstruction 6, 5
• Do not ignore fever or signs of infection—an infected obstructed kidney requires emergency decompression (percutaneous nephrostomy or ureteral stent) within hours 6, 5
• Do not attempt blind basket extraction without endoscopic visualization—this carries high risk of ureteral injury 6, 5

Practical Algorithm

1. Confirm no contraindications: Check for infection (urinalysis/culture), assess renal function (creatinine), and ensure pain is controlled 6
2. Proceed directly to ureteroscopy: Given the <10% spontaneous passage rate, schedule flexible ureteroscopy with holmium:YAG laser lithotripsy 1, 5
3. Emergency intervention only if: Fever/sepsis, anuria, uncontrolled pain, or progressive hydronephrosis develop before scheduled surgery 6, 5

Bottom line: An 8.8 mm proximal ureteral stone will not pass on its own. Schedule ureteroscopy without delay. 1, 5, 2