[A case of ectopic ureter with renal dysplasia simulating epididymal structure].

A 30-year-old man was admitted to our hospital suffering from fever and left scrotal swelling. Physical examination revealed an enlarged left epididymis, suggesting acute epididymitis. Intravenous pyelography showed non-functioning left kidney. On cystoscopy, the left ureter orifice did not open in the bladder, and it opened in the posterior urethra. An ureteral catheter was passed through this orifice to about 5 cm length and retrograde injection of contrast material demonstrated a dilated left ureter. CT also confirmed a dilated left ureter behind the bladder and the left kidney was not found. Left nephroureterectomy was performed. Microscopically, normal renal tissue was not recognized, and the lesion comprised a number of ducts covered with tall columnar epithelium having stereocilia and ducts resembling the thyroid gland. The former ducts resembled the ducts of epididymis. The pathological diagnosis was total dysplasia.