- Email: [email protected]
Re: Increased Risk of Diabetes in Patients With Urinary Calculi: A 5-Year Followup Study
LETTERS TO THE EDITOR/ERRATA
Reply by Authors: We thank Ghani et al for their interest in our study. They have raised a couple of pertinent issues. First, we only studied patients with ASA grades 1 and 2 physical status because at the inception of our study the wholesale use of the transesophageal Doppler probe had not been nationally recognized by the National Institute for Health and Clinical Excellence. Therefore, we based our ethics submission on the series published by Noblett et al (also from our institution), which dealt with fluid optimization in patients with ASA grades 1 and 2 physical status undergoing elective colorectal surgery.1 Our ethics committee agreed that this was the best way forward at the time. We now routinely use the probe for patients with ASA grades 1, 2 and 3 physical status undergoing radical cystectomy. At our institution patients with ASA grade 4 muscle invasive bladder cancer are not routinely offered cystectomy but, through our multidisciplinary team, referred for radical radiotherapy. The calculations for sample size, power, etc were also partly based on the study by Noblett et al,1 and this issue was, in fact, addressed in our correspondence with the editor. As Ghani et al indicate, the results of our study showed that control cystectomy times were significantly longer than in the trial group. There were 3 surgeons contributing to this study, and since it was fully randomized these were the absolute results. Therefore, this point needs no further discussion. Finally, we would agree that prolonged bowel manipulation increases postoperative ileus but, as our results convincingly demonstrated, the maximal interleukin-6 release was, in fact, during the bladder removal stage of the operation, not during the conduit/neobladder formation stage. Hence, we conclude that maximum tissue damage actually occurs during the extirpative phase of the operation, and postoperative ileus, wound infection, etc are more likely to be affected during this phase than during the reconstructive phase. We agree that one of the major potentials for robotic cystectomy may be decreased bowel manipulation, although Ghani et al may be unaware that in the United Kingdom there currently are only 28 robots installed at various institutions, and not all are used to perform cystectomy. Until this service is rolled out throughout the United Kingdom it is the duty of all urological surgeons and anesthetists to ensure that the open operation is performed as safely as possible (assuming that fully convincing evidence shows that robotic cystectomy is superior to open cystectomy in all domains). Furthermore, we recently studied preoperative cardiopulmonary exercise testing predicting postoperative outcomes (currently being prepared for publication), and found that there is no difference between open and laparoscopic cystectomy in terms of postoperative recovery and hospital stay. 1. Noblett SE, Snowden CP, Shenton BK et al: Randomized clinical trial assessing the effect of Doppler-optimized fluid management on outcome after elective colorectal resection. Br J Surg 2006; 93: 1069.
Re: Increased Risk of Diabetes in Patients With Urinary Calculi: A 5-Year Followup Study S.-D. Chung, Y.-K. Chen and H.-C. Lin J Urol 2011; 186: 1888 –1893.
To the Editor: This large, population based, case-control study demonstrates that patients diagnosed with urinary calculi are at increased risk for diabetes mellitus at 5-year followup, suggesting a role of insulin resistance in the pathogenesis of urolithiasis. Does this also mean that patients with diabetes are at increased risk for urinary calculi formation? It is known that diabetes can lead to lower urinary tract dysfunction. For example Teber et al recently demonstrated that patients with type 2 diabetes mellitus need a longer time to recover continence after laparoscopic radical prostatectomy compared to those without diabetes.1 Cells morphologically resembling interstitial cells (ICs) of Cajal of the gastrointestinal system have also recently been detected in the entire urinary tract, including ureters, in humans.2 ICs form a network in the urinary tract and make close contact with the nerves. In the bladder ICs are suggested to function as pacemaker cells responding to stretch or chemicals and modulating detrusor contractions.2,3 In the urethra ICs are suggested to modulate frequency and tone of urethral smooth muscle.4 However, their role in the ureter is not well known.
2279
2280
LETTERS TO THE EDITOR/ERRATA
We recently demonstrated that interstitial cells and neural tissue are significantly decreased in the bladder of rabbits with diabetes compared to controls,5 and suggested that diabetes might adversely affect expression and function of ICs in the bladder and urethra.6 Therefore, diabetes might also affect ureteral peristalsis and ureteral IC function, and lead to upper urinary tract dysfunction and thus urinary calculi formation. This issue needs further investigation. If ureteral IC function is adversely affected in diabetes, drugs might be developed that stimulate IC function to prevent urinary calculi, particularly in patients with diabetes. Respectfully, Abdullah Erdem Canda and Abidin Egemen Isgoren 1st Urology Clinic Ankara Ataturk Training and Research Hospital Ankara, Turkey 1. Teber D, Sofikerim M, Ates M et al: Is type 2 diabetes mellitus a predictive factor for incontinence after laparoscopic radical prostatectomy? A matched pair and multivariate analysis. J Urol 2010; 183: 1087. 2. van der Aa F, Roskams T, Blyweert W et al: Identification of kit positive cells in the human urinary tract. J Urol 2004; 171: 2492. 3. Wiseman OJ, Fowler CJ and Landon DN: The role of the human bladder lamina propria myofibroblast. BJU Int 2003; 91: 89.
4. Sergeant GP, Hollywood MA, McCloskey KD et al: Specialised pacemaking cells in the rabbit urethra. J Physiol 2000; 526: 359. 5. Canda AE, Aktas S, Turna B et al: Does diabetes affect the distribution of interstitial cells and neuronal tissue in the bladder, prostate and urethra of rabbits? Cent Eur J Med 2010; 5: 108. 6. Canda AE: Diabetes might adversely affect expression and function of interstitial cells in the urinary bladder and urethra in humans: a new mechanism in the development of diabetic lower urinary dysfunction? Med Hypotheses 2011; 76: 632.
Re: Implications of Pacemakers and Implantable Cardioverter Defibrillators in Urological Practice S. S. Ubee, V. S. Kasi, D. Bello and R. Manikandan J Urol 2011; 186: 1198 –1205.
To the Editor: I read with great interest this article regarding the safety of urological surgery in patients with implantable pacemakers and defibrillators. Our patients are aging, and the presence of these lifesaving devices is ever more common. More and more, procedures are now being performed at doctor offices. This shift is due to many different causes, including technology, patient comfort, economics and time. One omission in the article was any discussion of these devices with current microwave technology, as well as other heat treatments for prostatic enlargement. There has been little published about this issue. We are told that the Targis® device has been tested with pacemakers but it is contraindicated in patients with defibrillators. However, it is known that patients with defibrillators have been treated safely. Many other technologies have not been cleared by the Food and Drug Administration for use in patients with pacemakers. It would have been helpful if these devices, which are used in outpatient office procedures, were discussed. Respectfully, David H. Kauder 220 Humphrey St., Unit 203 Marblehead, Massachusetts 01945-1668 e-mail: [email protected]
Reply by Authors: We are thankful to Kauder for his interest in our article and appreciate his valuable comments. One of the objectives while writing this review article was to keep a universal appeal and deal with devices and procedures that are common to urologists across the continents. Targis and other devices based on microwave technology have been shown to have promising results in management of benign prostatic obstruction, although they are still being used only at selected centers. Also, the amount of information and the number of devices discussed were limited by the permitted word length of the article, hence our decision to be selective about the devices covered.
Reply by Authors: We thank Ghani et al for their interest in our study. They have raised a couple of pertinent issues. First, we only studied patients with ASA grades 1 and 2 physical status because at the inception of our study the wholesale use of the transesophageal Doppler probe had not been nationally recognized by the National Institute for Health and Clinical Excellence. Therefore, we based our ethics submission on the series published by Noblett et al (also from our institution), which dealt with fluid optimization in patients with ASA grades 1 and 2 physical status undergoing elective colorectal surgery.1 Our ethics committee agreed that this was the best way forward at the time. We now routinely use the probe for patients with ASA grades 1, 2 and 3 physical status undergoing radical cystectomy. At our institution patients with ASA grade 4 muscle invasive bladder cancer are not routinely offered cystectomy but, through our multidisciplinary team, referred for radical radiotherapy. The calculations for sample size, power, etc were also partly based on the study by Noblett et al,1 and this issue was, in fact, addressed in our correspondence with the editor. As Ghani et al indicate, the results of our study showed that control cystectomy times were significantly longer than in the trial group. There were 3 surgeons contributing to this study, and since it was fully randomized these were the absolute results. Therefore, this point needs no further discussion. Finally, we would agree that prolonged bowel manipulation increases postoperative ileus but, as our results convincingly demonstrated, the maximal interleukin-6 release was, in fact, during the bladder removal stage of the operation, not during the conduit/neobladder formation stage. Hence, we conclude that maximum tissue damage actually occurs during the extirpative phase of the operation, and postoperative ileus, wound infection, etc are more likely to be affected during this phase than during the reconstructive phase. We agree that one of the major potentials for robotic cystectomy may be decreased bowel manipulation, although Ghani et al may be unaware that in the United Kingdom there currently are only 28 robots installed at various institutions, and not all are used to perform cystectomy. Until this service is rolled out throughout the United Kingdom it is the duty of all urological surgeons and anesthetists to ensure that the open operation is performed as safely as possible (assuming that fully convincing evidence shows that robotic cystectomy is superior to open cystectomy in all domains). Furthermore, we recently studied preoperative cardiopulmonary exercise testing predicting postoperative outcomes (currently being prepared for publication), and found that there is no difference between open and laparoscopic cystectomy in terms of postoperative recovery and hospital stay. 1. Noblett SE, Snowden CP, Shenton BK et al: Randomized clinical trial assessing the effect of Doppler-optimized fluid management on outcome after elective colorectal resection. Br J Surg 2006; 93: 1069.
Re: Increased Risk of Diabetes in Patients With Urinary Calculi: A 5-Year Followup Study S.-D. Chung, Y.-K. Chen and H.-C. Lin J Urol 2011; 186: 1888 –1893.
To the Editor: This large, population based, case-control study demonstrates that patients diagnosed with urinary calculi are at increased risk for diabetes mellitus at 5-year followup, suggesting a role of insulin resistance in the pathogenesis of urolithiasis. Does this also mean that patients with diabetes are at increased risk for urinary calculi formation? It is known that diabetes can lead to lower urinary tract dysfunction. For example Teber et al recently demonstrated that patients with type 2 diabetes mellitus need a longer time to recover continence after laparoscopic radical prostatectomy compared to those without diabetes.1 Cells morphologically resembling interstitial cells (ICs) of Cajal of the gastrointestinal system have also recently been detected in the entire urinary tract, including ureters, in humans.2 ICs form a network in the urinary tract and make close contact with the nerves. In the bladder ICs are suggested to function as pacemaker cells responding to stretch or chemicals and modulating detrusor contractions.2,3 In the urethra ICs are suggested to modulate frequency and tone of urethral smooth muscle.4 However, their role in the ureter is not well known.
2279
2280
LETTERS TO THE EDITOR/ERRATA
We recently demonstrated that interstitial cells and neural tissue are significantly decreased in the bladder of rabbits with diabetes compared to controls,5 and suggested that diabetes might adversely affect expression and function of ICs in the bladder and urethra.6 Therefore, diabetes might also affect ureteral peristalsis and ureteral IC function, and lead to upper urinary tract dysfunction and thus urinary calculi formation. This issue needs further investigation. If ureteral IC function is adversely affected in diabetes, drugs might be developed that stimulate IC function to prevent urinary calculi, particularly in patients with diabetes. Respectfully, Abdullah Erdem Canda and Abidin Egemen Isgoren 1st Urology Clinic Ankara Ataturk Training and Research Hospital Ankara, Turkey 1. Teber D, Sofikerim M, Ates M et al: Is type 2 diabetes mellitus a predictive factor for incontinence after laparoscopic radical prostatectomy? A matched pair and multivariate analysis. J Urol 2010; 183: 1087. 2. van der Aa F, Roskams T, Blyweert W et al: Identification of kit positive cells in the human urinary tract. J Urol 2004; 171: 2492. 3. Wiseman OJ, Fowler CJ and Landon DN: The role of the human bladder lamina propria myofibroblast. BJU Int 2003; 91: 89.
4. Sergeant GP, Hollywood MA, McCloskey KD et al: Specialised pacemaking cells in the rabbit urethra. J Physiol 2000; 526: 359. 5. Canda AE, Aktas S, Turna B et al: Does diabetes affect the distribution of interstitial cells and neuronal tissue in the bladder, prostate and urethra of rabbits? Cent Eur J Med 2010; 5: 108. 6. Canda AE: Diabetes might adversely affect expression and function of interstitial cells in the urinary bladder and urethra in humans: a new mechanism in the development of diabetic lower urinary dysfunction? Med Hypotheses 2011; 76: 632.
Re: Implications of Pacemakers and Implantable Cardioverter Defibrillators in Urological Practice S. S. Ubee, V. S. Kasi, D. Bello and R. Manikandan J Urol 2011; 186: 1198 –1205.
To the Editor: I read with great interest this article regarding the safety of urological surgery in patients with implantable pacemakers and defibrillators. Our patients are aging, and the presence of these lifesaving devices is ever more common. More and more, procedures are now being performed at doctor offices. This shift is due to many different causes, including technology, patient comfort, economics and time. One omission in the article was any discussion of these devices with current microwave technology, as well as other heat treatments for prostatic enlargement. There has been little published about this issue. We are told that the Targis® device has been tested with pacemakers but it is contraindicated in patients with defibrillators. However, it is known that patients with defibrillators have been treated safely. Many other technologies have not been cleared by the Food and Drug Administration for use in patients with pacemakers. It would have been helpful if these devices, which are used in outpatient office procedures, were discussed. Respectfully, David H. Kauder 220 Humphrey St., Unit 203 Marblehead, Massachusetts 01945-1668 e-mail: [email protected]
Reply by Authors: We are thankful to Kauder for his interest in our article and appreciate his valuable comments. One of the objectives while writing this review article was to keep a universal appeal and deal with devices and procedures that are common to urologists across the continents. Targis and other devices based on microwave technology have been shown to have promising results in management of benign prostatic obstruction, although they are still being used only at selected centers. Also, the amount of information and the number of devices discussed were limited by the permitted word length of the article, hence our decision to be selective about the devices covered.