A 30-year-old woman develops continuous leakage of urine from the vagina 10 days after a difficult forceps delivery. Intravenous indigo carmine is administered, and a vaginal swab shows blue staining. This finding indicates which type of fistula?
- A Vesicovaginal fistula
- B Ureterovaginal fistula ✓
- C Urethrovaginal fistula
- D Rectovaginal fistula
Correct answer: B. Ureterovaginal fistula
Explanation
Intravenous indigo carmine (or IVP dye) is excreted by the kidneys via the ureters. Blue staining of a vaginal swab after IV administration indicates a ureterovaginal fistula, as the dye reaches the vagina through the ureter without passing through the bladder. For vesicovaginal fistula, intravesical methylene blue is used, and the swab stains blue. The three-swab test with these dyes differentiates the fistula type.
Reference: Shaw's Textbook of Gynaecology, 18th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.