Authors' Response to Tang et al.

To the Editor:

W e thank Tang and associates from Xiangya Hospital in Changsha, China, for their interest in our article. An ureteral Double-J stent is traditionally inserted for continuation of urinary flow, prevention or management of obstruction, and treatment of ureter-related urinary leakage in upper urinary tract diseases and procedures. ^{1 –3} Insertion of an ureteral stent can cause complaints or complications. ^1,3,4 Watery vaginal discharge (incontinence) or hematuria may be the primary presentation of ureteral injury. ^{5 –7} Microscopic or gross hematuria can occur after the placement of a ureteral stent. ^{1 –4,7,8} In addition, hematuria (microscopic or gross) may be the primary presentation of complications such as ureteral injury, ureteral erosion, migration of the stent, or ureteral fistulization after insertion of a ureteral stent. ^1,5,7

Intravenous (including intracaval) migration of an ureteral Double-J stent can be seen in a patient with a good general condition and normal vital signs. ⁷ It seems that in a patient with intravenous (including intracaval) migration of an ureteral stent, the main reason for normal vital signs is the probable obstruction of intraluminal flow of the stent because of hematuria ¹ and blood clotting. Attention to the probable occurrence of deep vein thrombosis ⁷ and thromboembolism ⁹ should not be forgotten after the diagnosis and management of intracaval (intravenous) migration of an ureteral stent.

Fluoroscopy and radiography of the kidneys, ureters, and bladder are important approaches for evaluation of the position of an ureteral stent during and after insertion. ^1,7,10 In a patient despite a good general condition, a complication such as migration may be found. ⁷ Consideration of the patient's signs and symptoms, microscopic hematuria, and periodic radiologic monitoring are necessary after the use of an ureteral Double-J stent. ^7,10