Management of Left Distal Ureteric Calculus with Mild Hydroureteronephrosis
Retrograde ureteral stenting is the recommended first-line treatment for this patient with an 8x6 mm left distal ureteric calculus causing mild hydroureteronephrosis. 1
Assessment of Current Condition
- CT KUB findings show a left distal ureteric calculus measuring 8x6 mm (HU 536) located 2.5 cm proximal to the left vesicoureteric junction (VUJ), causing mild hydroureteronephrosis and periureteric fat stranding 1
- Bilateral renal cortical cysts are present but are incidental findings that do not require immediate intervention 1
- Mild prostatomegaly (28cc) is noted but is not directly related to the acute urinary obstruction 1
Treatment Algorithm
Step 1: Determine Need for Intervention
- The stone is 8x6 mm in size, which exceeds the threshold where spontaneous passage is likely 1
- The presence of hydroureteronephrosis indicates obstruction that requires intervention 1
- The distal location (2.5 cm from VUJ) makes this amenable to endoscopic management 1
Step 2: Select Appropriate Intervention
- For distal ureteric calculi requiring intervention, retrograde ureteral stenting is the recommended first-line therapy 1
- Ureteroscopy (URS) with stone extraction or fragmentation offers the highest single-procedure stone-free rate (approximately 90% vs 72% for SWL) 1
- Shock wave lithotripsy (SWL) can be offered as an alternative if the patient declines URS 1
Step 3: Pre-Procedure Considerations
- Urine culture should be obtained prior to intervention to rule out infection 1
- If infection is suspected or proven, appropriate antibiotic therapy should be administered before the procedure 1
- Patients should be informed about the benefits and risks of each treatment option 1
Evidence-Based Comparison of Treatment Options
Ureteroscopy (URS)
- Higher stone-free rates in a single procedure compared to SWL, particularly for distal ureteral stones 1
- Success rates of approximately 90% for distal ureteral stones 1
- Potential complications include ureteral injury (3% for distal ureter), stricture (1%), and UTI (4%) 1
- May require stent placement post-procedure, though stenting can be omitted in uncomplicated cases 1
Shock Wave Lithotripsy (SWL)
- Lower morbidity and complication rate compared to URS 1
- Lower stone-free rate (approximately 72%) for distal ureteral stones 1
- May require multiple sessions for complete stone clearance 1
- Potential complications include steinstrasse (stone street), UTI, and incomplete fragmentation 1
Medical Expulsive Therapy (MET)
- Not recommended as primary therapy for stones >8 mm as they typically require surgical intervention 1
- Could be considered as an adjunct to other treatments to facilitate passage of residual fragments 2
- Alpha-blockers like tamsulosin can increase stone expulsion rates and reduce expulsion time 2
Post-Procedure Management
- Follow-up imaging should be performed to confirm stone clearance 1
- If stent is placed, it should be removed once the stone is cleared and edema has resolved 1
- Metabolic evaluation may be considered to prevent recurrence 1
Special Considerations
- The bilateral renal cysts noted on imaging are incidental findings and do not require immediate intervention unless symptomatic or suspicious for malignancy 1
- The mild prostatomegaly should be addressed separately after resolution of the acute stone episode 1
- If the patient has impaired renal function or signs of infection/sepsis, more urgent decompression would be indicated 1
Pitfalls to Avoid
- Blind basketing (stone extraction without endoscopic visualization) should never be performed due to high risk of ureteral injury 1
- Delaying intervention beyond 4-6 weeks risks irreversible kidney damage from prolonged obstruction 1
- Failing to obtain appropriate pre-procedure imaging to confirm stone location and size 1
- Neglecting to evaluate for and treat urinary tract infection before intervention 1