Embryology USMLE Step 1 Practice Question
A mother brings her 5-year-old daughter to the physician complaining that the child still seems to regularly wet herself despite having been toilet-trained. The physician orders an IV pyelogram, which demonstrates a complete duplication of the ureter on the right side. Although one ureter opens normally into the bladder, the other opens ectopically into the vagina. Which of the following is the most likely cause of this congenital anomaly?
Answer choices
- AEarly division of the ureteric budCorrect answer
- BImproper union of excretory tubules and collecting tubules
- CDuplication of the proximal mesonephric (Wolffian) duct
- DEctopic growth of the pronephros
- EPersistence of embryonic ureters as the kidney ascends from the pelvis to the superior abdomen
- FFailure of the ureteric bud to separate from the mesonephric duct during week 5 of development
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