Is a 4.5mm stone in the distal right ureter, causing mild right hydroureteronephrosis, an indication for Ureteroscopic (Ureteroscopy) Lithotripsy?

From the Guidelines

Ureteroscopic lithotripsy is the recommended treatment for the 4.5 mm stone in the right distal ureter causing mild hydroureteronephrosis, given its high success rates and low complication rates for distal ureteral stones. For ureteral stones of this size (4-10 mm), active intervention is typically recommended as spontaneous passage is less likely 1. Ureteroscopic lithotripsy is an appropriate first-line treatment option, involving the insertion of a small scope through the urinary tract to visualize and fragment the stone using laser energy, followed by stone fragment removal. This procedure is minimally invasive and has high success rates for distal ureteral stones, with an overall stone-free rate of 94% achieved with either a rigid or semirigid ureteroscope 1.

The decision to proceed with ureteroscopic lithotripsy should consider factors like stone composition, patient preference, and comorbidities. Alternative options include extracorporeal shock wave lithotripsy or medical expulsive therapy with alpha-blockers like tamsulosin 0.4 mg daily, but these may be less effective for stones in this location. According to the 2007 guideline for the management of ureteral calculi, both SWL and URS are acceptable first-line treatments, but URS is associated with a better chance of becoming stone-free with a single procedure, although it has higher complication rates 1.

The potential complications of ureteroscopic lithotripsy, such as ureteral perforation, stricture formation, and infection, should be discussed with the patient, along with the benefits of the procedure. Most patients can return to normal activities within a few days after ureteroscopic lithotripsy, though mild discomfort and blood in urine may occur temporarily. The patient should be informed about the existing active treatment modalities, including the relative benefits and risks associated with each modality, and should be followed with periodic imaging studies to monitor stone position and to assess for hydronephrosis 1.

Key points to consider in the management of this patient include:

• The size and location of the stone, which is 4.5 mm in the right distal ureter
• The presence of mild hydroureteronephrosis, which indicates the need for prompt treatment
• The patient's overall health and comorbidities, which may affect the choice of treatment
• The potential benefits and risks of ureteroscopic lithotripsy, including the high success rates and low complication rates for distal ureteral stones.

From the Research

Indications for Ureteroscopic Lithotripsy

• The patient has mild right hydroureteronephrosis with a suspected stone at the right hemi-pelvic region, with the stone measuring about 4.5 mm.
• Ureteroscopic lithotripsy is a common treatment for ureteral stones, especially for stones in the middle and lower ureter 2.
• The success rate of ureteroscopic lithotripsy can be affected by factors such as stone size, location, and impaction 2.

Considerations for Ureteroscopic Lithotripsy

• The stone size of 4.5 mm is relatively small, which may favor ureteroscopic lithotripsy as a treatment option 3.
• However, the location of the stone at the distal right ureter, which could not be clearly identified, may pose a challenge for ureteroscopic lithotripsy 2.
• The degree of hydronephrosis is mild, which may not significantly impact the success rate of ureteroscopic lithotripsy 2.

Comparison with Other Treatment Options

• Extracorporeal shock wave lithotripsy (SWL) is another common treatment for ureteral stones, but it may have a higher retreatment rate compared to ureteroscopic lithotripsy 3.
• Ureteroscopic lithotripsy may have a higher success rate and fewer retreatments compared to SWL, but it may also have a higher complication rate and longer hospital stay 3.
• The cost-utility analysis of ureteroscopic lithotripsy versus SWL for treatment of urinary stones smaller than 2 cm suggests that SWL may have a better cost-utility profile in some clinical settings 4.

Predictors of Ipsilateral Hydronephrosis

• Increasing stone diameter, prior ipsilateral ureteroscopic lithotripsy, longer operative duration, and renal colic symptoms are independent predictors of ipsilateral hydronephrosis after ureteroscopic lithotripsy 5.
• However, these factors may not be directly applicable to the patient's case, as the stone size is relatively small and the degree of hydronephrosis is mild.

Note: The last study 6 is not relevant to the question and is not cited in the response.