In the management of a 4 mm ureteric calculus at the vesicoureteric junction (VUJ) in a 30-year-old with mild renal colic, medical expulsive therapy (MET) is initiated with an alpha-blocker. According to EAU guidelines, the stone most likely to pass spontaneously based on size and location is a stone:

• A 8 mm at the pelviureteric junction (PUJ)
• B 4 mm at the vesicoureteric junction (VUJ) ✓
• C 6 mm at the mid-ureter
• D 5 mm in the upper ureter

Explanation

Spontaneous passage rates depend on stone size and location. Distal ureteric (VUJ) stones have the highest passage rates: 4 mm stones pass in ~90% of cases, and even 5–6 mm distal stones pass in 50–70%. Proximal (PUJ) and mid-ureteric stones pass less frequently for equivalent sizes due to less ureteric peristalsis and proximity to the wider renal pelvis. Alpha-blockers (tamsulosin) increase distal ureteric stone passage by relaxing smooth muscle. Stones >6 mm at any location rarely pass spontaneously.

Reference: Bailey & Love's Short Practice of Surgery, 27th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.