From the Guidelines
ESWL is not the first-line treatment for a 7x6 mm obstructing calculus in the distal ureter causing mild to moderate hydronephrosis, and ureteroscopy (URS) is recommended as the primary approach. According to the American Urological Association/Endourological Society guideline [ 1 ], URS has a higher stone-free rate compared to ESWL, especially for distal ureteral stones (90% for URS versus 72% for SWL). The guideline strongly recommends URS as first-line therapy for patients with mid or distal ureteral stones who require intervention [ 1 ].
The location of the stone in the distal ureter and the presence of hydronephrosis indicate that prompt intervention is necessary to relieve the obstruction. Ureteroscopy with laser lithotripsy offers immediate stone clearance and is associated with higher success rates compared to ESWL. While ESWL has the least morbidity and lowest complication rate [ 1 ], the higher stone-free rate of URS makes it the preferred approach for this case.
Key considerations for the treatment approach include:
- The size and location of the stone (7x6 mm in the distal ureter)
- The presence of mild to moderate hydronephrosis, indicating obstruction
- The higher stone-free rate of URS compared to ESWL for distal ureteral stones
- The recommendation for URS as first-line therapy for patients with mid or distal ureteral stones who require intervention [ 1 ]
In terms of management, the patient should receive appropriate pain management and alpha-blockers to facilitate stone passage, but given the stone size and hydronephrosis, surgical intervention with URS is likely necessary.
From the Research
Indications for ESWL
- The patient has a 7x6 mm HU 592 obstructed calculus in the distal ureter, which is causing mild to moderate hydronephrosis.
- According to the study by 2, the degree of hydronephrosis is a significant predicting factor for stone-free status after ESWL.
- However, the study by 2 also found that the stone-free rate decreases with increasing stone size and degree of hydronephrosis.
Efficacy of ESWL for Distal Ureteral Stones
- The study by 3 compared ESWL to percutaneous nephrolithotomy (PCNL) and retrograde intrarenal surgery (RIRS) for kidney stones, but did not specifically address distal ureteral stones.
- The study by 4 compared ESWL to flexible ureterorenoscopy (URS) for untreated renal calculi, and found that URS had higher stone-free rates and fewer reinterventions than ESWL.
- However, the study by 5 found that ESWL was a safe and efficient method for patients with ureteral lithiasis and double-J catheters inserted for infected hydronephrosis.
Considerations for Treatment
- The size and location of the stone, as well as the degree of hydronephrosis, should be taken into account when deciding on a treatment plan.
- The study by 2 suggests that alternative treatments, such as ureteroscopic lithotripsy, may be appropriate as initial treatment or after failure of one session of ESWL for patients with a solitary proximal ureteral stone and moderate to severe hydronephrosis.
- The study by 5 found that the presence of double-J catheters inserted for infected hydronephrosis does not affect the stone-free rate or complication rate of ESWL.