A 42-year-old woman develops continuous urinary leakage per vaginum 9 days after total abdominal hysterectomy. The classic three-swab test is performed: the uppermost swab placed in the vault is soaked with clear urine, while the middle and lower swabs remain dry despite methylene blue instilled into the bladder. This finding indicates:

• A Ureterovaginal fistula ✓
• B Vesicovaginal fistula
• C Urethrovaginal fistula
• D Vesicouterine fistula

Explanation

In the three-swab test, blue-stained urine wetting the upper swab means the leak comes from the bladder, that is a vesicovaginal fistula. Here the upper swab carries unstained urine, meaning the fluid bypasses the bladder entirely and enters the vagina above it, which localizes the leak to the ureter. Ureteric injury occurs in about 0.5 to 1.5 percent of hysterectomies, usually at the level of the uterine artery or the infundibulopelvic ligament, and requires stenting or ureteroneocystostomy rather than vaginal repair.

Reference: DC Dutta's Textbook of Gynecology, 7th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.