Dear editor,

I read with great interest the article on non-invasive removal of double-J (DJ) stent.(1) It is always a welcome to remove DJ stent in children without anesthesia and cystoscopy. However, I wish make some pertinent observations regarding the paper.

Firstly, this technique described by authors is not new. As early as 1986, Siegel et.al developed a similar technique of stent retrieval using a monofilament nylon extraction string which was tied to the distal end of the DJ stent and its outer end taped to the penis or abdomen.(2) The technique has subsequently been modified by several other researchers.(3,4) The authors also completely ignored citing several large randomized controlled studies and systematic reviews that are relevant to the paper.(5,6) Further, authors should have also clearly stated as to what was their modification and as to how was it better than the other existing techniques of string-based double-J stent removal. Secondly, the authors should have discussed the advantages and disadvantages of their technique in comparison to the alternative techniques such as the Vellore technique.(7) Thirdly, spontaneous expulsion of the free end of the extraction string is a possibility rather than a certainty. It would be interesting to know, in how many of their patients the authors faced this problem of non expulsion of the extraction thread in urine stream. Fourthly, once expelled in urine stream, how did the authors prevented premature accidental pulling of the thread by the child or by his parents? Accidental dislodgement is as high as 24% in one study.(8) Fifthly, in case of bilateral stents that require removal at different dates, how did the authors manage to identify the side of stent that is to be removed? Sixthly, did the authors encounter spontaneous knotting of thread inside bladder? Seventhly, the silk string is prone for infections owing to its braided nature. This is especially true when the string is hanging outside.(9) It may also introduce ascending infection. Did the authors consider using any other monofilament strings to reduce the risk of infection? Did they use prophylactic antibiotics? What was the rate of UTI in the authors’ series? Finally, the practical utility of the article would have been enhanced had the authors added to their discussion about newer stents such as the bio-degradable stents(10) and the magnetic tipped stents(11) which render their removal either unnecessary or easy respectively.

Notwithstanding these critical observations, I would like to congratulate the author for having given a new perspective to the removal of DJ stent in children without anesthesia or cystoscopy.

REFERENCES

1. Sarkar A, Kinjalk M. Removal of double-J stent in children without anesthesia or cystoscopy: A useful technique. Pediatr Surg Trop 2024 April-June; 1(2): 99-101

2. Siegel A, Altadonna V, Ellis D, Hulbert W, Elder J, Duckett J. Simplified method of indwelling ureteral stent removal. Urology. 1986 Nov; 28(5):429. 

3. Kajbafzadeh AM, Nabavizadeh B, Keihani S, Hosseini Sharifi SH. Revisiting the tethered ureteral stents in children: a novel modification. Int Urol Nephrol. 2015 Jun; 47(6): 881-5. 

4. Hu W, Song Y, Li Y, Li Y, Mu J, Zhong X, Chen Y, Wu R, Xiao Y, Huang C. Novel method to decrease the exposure time of the extraction string of the ureteral stent and its efficiency and safety verification in the clinic. Sci Rep. 2021 Nov 16;11(1):22358. 

5. Oliver R, Wells H, Traxer O, Knoll T, Aboumarzouk O, Biyani CS, Somani BK; YAU Group. Ureteric stents on extraction strings: a systematic review of literature. Urolithiasis. 2018 Apr; 46(2): 129-136. 

6. Kim DJ, Son JH, Jang SH, Lee JW, Cho DS, Lim CH. Rethinking of ureteral stent removal using an extraction string; what patients feel and what is patients' prefer-ence? : a randomized controlled study. BMC Urol. 2015 Dec 9; 15: 121. 

7. Sundaramurthy S, Joseph Thomas R, Herle K, Jeyaseelan, Mathai J, Jacob Kurian J. Double J stent removal in paediatric patients by Vellore Catheter Snare technique: a randomised control trial. J Pediatr Urol. 2019 Dec; 15 (6): 661.e1-661.e8.

8. Althaus AB, Li K, Pattison E, Eisner B, Pais V, Steinberg P. Rate of dislodgment of ureteral stents when using an extraction string after endoscopic urological surgery. J Urol. 2015 Jun; 193(6): 2011-4.

9. Batie SF, Coco CT, Reddy S, Pritzker K, Traylor JM, Tracy JD, Chan YY, Stanasel I, Schlomer BJ, Jacobs MA, Baker LA, Peters CA. Ureteral stent extraction strings in children: Stratifying the risk of post operative urinary tract infection. J Pediatr Urol. 2023 Oct; 19(5): 515.e1-515.e5. 

10. Chew BH, Paterson RF, Clinkscales KW, Levine BS, Shalaby SW, Lange D. In vivo evaluation of the third generation biodegradable stent: a novel approach to avoiding the forgotten stent syndrome. J Urol. 2013 Feb; 189 (2): 719-25.

11. Macaluso JN Jr, Deutsch JS, Goodman JR, Appell RA, Prats LJ Jr, Wahl P. The use of the Magnetip double-J ureteral stent in urological practice. J Urol. 1989 Sep; 142 (3): 701-3.

Ijaz Ahmed

Department of General Surgery,

Government Cuddalore Medical College, Chidambaram 608002, India

AUTHORS’REPLY

Dear editor,

I read with great interest the long critical letter by Dr. Ijaz Ahmad. I appreciate the efforts taken by him to review the literature. Some of his points are really interesting to read. However, we wish to make the following observations: 

1. All the studies cited by him have been done in adults. Ours is exclusively done in children.

2. Braided threads causing infection is not a significant issue. Level-1 evidence comparing monofilament versus braided suture in the urinary tract is not available. When a larger foreign body (stent) itself is left inside the bladder, a smaller thread ought not to be a cause of great concern.

3. Bilateral stents are usually removed at the same time. Whether the right or the left stent comes out first is immaterial.

4. For babies on diapers, accidental premature removal is unlikely.

5. This is the first study of its kind from India in the pediatric age group. General anesthesia and cystoscopy for stent removal in this setting is always difficult. If it can be avoided, so much the better.

6. If the extraction string does not emerge spontaneously, all is not lost; it can always be pulled out by the conventional cystoscopic method.

7. Other modern stents mentioned by Dr Ahmed are too costly and we do not want to escalate the cost of care as ours is a charitable hospital.

Thank you for the opportunity to respond to the criticisms.

Atreyee Sarkar

Department of Pediatric Surgery,

Dr. Balasaheb Vikhey Patil Rural Medical College, Loni - 413736, Ahmednagar, Maharashtra, India