Is a 4.6 mm left distal ureteral stone at the S1 level with 697 HU attenuation and minimal left hydroureter an indication for ureteroscopy with laser lithotripsy and double‑J stent placement?

Management of 4.6 mm Distal Ureteral Stone

A 4.6 mm left distal ureteral stone at the S1 level with minimal hydroureter should be managed initially with conservative medical expulsive therapy (alpha-blocker plus NSAID) for 4–6 weeks, not immediate ureteroscopy with laser lithotripsy and DJ stent placement. 1, 2

Initial Conservative Management is Indicated

For uncomplicated ureteral stones ≤10 mm, medical expulsive therapy (MET) is the recommended first-line approach. 1, 2 Your stone at 4.6 mm falls well within this range and should be given a trial of conservative management before proceeding to surgical intervention.

Why Conservative Management First?

• Stones 2–4 mm pass spontaneously in 83% of cases, with an average passage time of 12.2 days, and only 17% require intervention. 3
• Stones 4–6 mm pass spontaneously in approximately 50% of cases, with an average passage time of 22.1 days. 3
• For 95% of stones 2–4 mm to pass, it takes up to 40 days. 3
• Distal stone location (as in your case at S1 level) is associated with higher spontaneous passage rates compared to proximal stones. 3

Appropriate Conservative Management Protocol

Prescribe an alpha-blocker (tamsulosin) combined with an NSAID for pain control. 4, 1 Patients must be counseled that alpha-blockers are used off-label for this indication, with potential side effects including orthostatic hypotension, dizziness, and retrograde ejaculation. 1

Conservative management requires:

• Well-controlled pain with oral analgesics 1
• No clinical evidence of sepsis or infection 1
• Adequate renal function 1
• Maximum duration of 4–6 weeks from initial presentation 1, 2, 5

Mandatory monitoring with periodic imaging (low-dose CT or renal ultrasound) is required to track stone position and assess for progression of hydronephrosis. 1

When to Proceed with Ureteroscopy and Laser Lithotripsy

Immediate ureteroscopy with DJ stent is NOT indicated unless:

Absolute Indications for Urgent Intervention

• Sepsis or urinary tract infection with obstruction (requires urgent decompression via percutaneous nephrostomy or ureteral stenting first, NOT immediate stone removal) 1, 2, 6
• Anuria in an obstructed kidney 1, 5
• Intractable pain despite medical management 5
• Solitary kidney or bilateral obstruction 5

Indications for Elective Ureteroscopy After Conservative Trial

• Failed conservative management after 4–6 weeks 1, 2, 5
• Uncontrolled pain despite optimal medical therapy 1
• Development of fever or signs of infection 1
• Progressive hydronephrosis or declining renal function 5
• Stone growth on follow-up imaging 5

Your Specific Case Analysis

Your stone presents with "minimal left sided hydroureter" only, which does not constitute an absolute indication for immediate intervention. 7 The high attenuation value (697 HU) suggests a calcium-based stone, which responds well to both conservative management and ureteroscopy if needed later. 4

If ureteroscopy becomes necessary after failed conservative management:

• Ureteroscopy with holmium laser lithotripsy achieves 90–95% stone-free rates for stones <10 mm in a single session. 2
• Routine pre-operative ureteral stenting is NOT recommended, as successful access is achievable on the initial attempt in most cases. 4, 2
• Post-operative DJ stent placement is NOT routinely required after uncomplicated ureteroscopy, but may be considered based on intra-operative findings (ureteral injury, stricture, or planned secondary procedure). 4, 2

Critical Pitfalls to Avoid

Do not delay intervention beyond 6 weeks if conservative management fails, as this risks irreversible kidney damage. 1, 2, 5

Do not proceed with definitive stone treatment if infection develops—drain first with percutaneous nephrostomy or ureteral stent, treat infection with antibiotics, then address the stone definitively once infection resolves. 2, 6

Do not use alpha-blockers in patients with sepsis or significant obstruction requiring urgent decompression. 1

Obtain urine culture before any procedure and treat bacteriuria; antibiotic prophylaxis is mandatory for ureteroscopy but not for conservative management in low-risk patients. 2