Book Part | 2011 | Urinary Tract Stone Disease , pp.383 - 390
The incidence of stone disease has been rising in recent years and calcium-containing stones (calcium oxalate) are the most prevalent stone types of all. In an attempt to mimic the stone formation process in humans and to understand the mechanisms involved, a number of theoretical, chemical, and animal models have been developed. In these experimental models, formation of calcium oxalate deposits in the kidney can be demonstrated in a short period of time by enabling the physicians to study the processes involved in stone maturation, as well as for examining the role of inhibitors and promoters of crystal growth. Although rabbits an . . .d dogs have also been used, rats are the most commonly used animals for the study of nephrolithiasis. An accurate and reliable animal model may allow us to develop newer treatment algorithms and medications that may help to better understand the pathogenesis of stone formation and direct improved methods of stone prevention. There are many similarities between experimental nephrolithiasis-induced rat model and human kidney stone formation where oxalate metabolism is considered to be almost identical between rats and humans. The accumulated data so far have clearly shown that rat models of nephrolithiasis may help us to evaluate the various phases of stone formation including nucleation, aggregation, and retention of crystals. Last but not least, although the pathogenesis of stone formation can be studied in animal models, the limitations of these models should always be kept in mind. © 2011 Springer-Verlag London Limited Daha fazlası Daha az
Erturhan, S. | Bayrak, O. | Sarica, K.
Letter | 2013 | Urology81 ( 6 ) , pp.1381 - 1382
[No abstract available]
Gürbüz, C. | Öztürk, M.I. | Koca, O. | Yildirim, A. | Ateş, F. | Eryildirim, B. | Sarica, K.
Article | 2011 | Turk Uroloji Dergisi37 ( 3 ) , pp.252 - 256
Objective: In this study, the adequacy of technical equipment used in the treatment of renal stone along with treatment approaches was evaluated. Materials and methods: Between January 2010 and June 2010, 106 urology residents and specialists practicing in 10 different urology departments of training hospitals in İstanbul were asked to fill a questionnaire to evaluate the adequacy of necessary equipment and the treatment approaches for the treatment of renal stone. Results: Eighty percent of the physicians who participated in the study treated at least 8 patients with renal stone per month. While all participating clinics had rigid . . .nephro-scope, flexible ureterorenoscopy and electroshock wave lithotriptor were available in 41% and 49% of the clinics, respectively. The preferred radiologic evaluation before percutaneous nephrolithotomy (PNL) was intravenous pyelography, and abdominopelvic computed tomography in 72% and 69%, respectively. Tubeless PNL was not preferred by 71% of the participants. The first choice of treatment for coraliform stone was PNL and open surgery in 71% and 26% of participants, respectively. Fifty-four percent of the participants stated that PNL was applied for patients older than 12 years old. Retrograde intrarenal surgery was suggested by 26% of the participants for the treatment of symptomatic lower calix stone. Conclusion: It is encouraging that PNL application is performed in all clinics involved in this study, however, training hospitals should be more equipped Daha fazlası Daha az
Sarica, K. | Berber, M.
Book Part | 2011 | Urinary Tract Stone Disease , pp.421 - 430
When compared with the adult population, with an overall 1-2% incidence, urinary stone disease in children is relatively rare but often associated with metabolic abnormalities that can lead to recurrent stone episodes, emphasizing the necessity of full metabolic evaluation after the first stone episode. As a recurrent pathology, which may reveal functional as well and morphologic changes in the urinary tract, each child should be evaluated thoroughly on an individual basis. The pathology is associated with considerable morbidity, with recurrence rates of 6.5-44%. Without close follow-up and medical management, stone recurrence rates . . . have been reported to be as high as 50% within 5 or 6 years. In children, stone recurrence rates range widely from 3.6% to 67% and appears to be highest in children with metabolic abnormalities. The rate of stone recurrence in our previous report was 4% during a 5-year follow-up period. Given the high risk of subsequent calculus formation, it could be argued that all children should undergo some form of evaluation to determine the cause of their kidney stone and to help plan proper management strategies. It is well-known that certain groups of children should undergo a full metabolic workup due to the high risk of recurrence. Through these efforts future stone formation and/or growth may be controlled in the pediatric population, limiting the morbidity of this disease. © 2011 Springer-Verlag London Limited Daha fazlası Daha az
Tanriverdi, O. | Yencilek, F. | Koyuncu, H. | Yencilek, E. | Sarica, K.
Article | 2011 | Urology77 ( 2 ) , pp.305 - 308
Objectives To evaluate the causes of emergent stent placement during the postoperative early period after uncomplicated ureteroscopy in 23 patients. Methods Of 276 uncomplicated ureteroscopy procedures performed for the management of ureteral calculi, double-J stent placement was necessary on an emergent basis in 23 patients because of intolerable colic pain and extreme patient discomfort. All stents were inserted within 24 hours after the procedure. Results Of the 23 patients requiring emergent stent placement, 14 were men and 9 were women. The stones had been located in the lower ureter in 11, mid-ureter in 6, and upper ureter in . . .6 patients. All patients had undergone an uncomplicated procedure with no complication evident either during or immediately after ureteroscopic stone management. The intraoperative findings for the 23 patients revealed extensive edema formation, unrecognized small stones embedded in the edematous ureteral wall, unpassed small fragments gathered at the orifice, obstructing blood clots, and kinking of the ureter. A retrospective evaluation of the operative CD recordings and radiographic findings clearly showed that a longer operative time, repeated access, management of a large stone, impacted calculi with ureteral wall edema, a mildly narrowed ureteral segment, ignored caliceal small calculi, and a recent history of urinary tract infection contributed to the need for postoperative intervention. Conclusions Ureteral catheterization, at least in the form of overnight stent placement, might prevent the formation of transient ureteral obstruction, with resultant postoperative patient discomfort and colic pain evident in selected cases. © 2011 Elsevier Inc Daha fazlası Daha az
Sarica, K. | Tanriverdi, O. | Aydin, M. | Koyuncu, H. | Miroglu, C.
Article | 2011 | Urology78 ( 3 ) , pp.516 - 520
Objective: To comparatively evaluate the efficacy of ureteroscopic stone treatment immediately after the first colic attack and in an electively planned manner. Methods: A total of 145 patients underwent semirigid ureteroscopic removal of obstructive ureteral calculi using 2 different approaches (group 1, 69 patients, and group 2, 76 patients). The 69 patients in group 1 were treated with appropriate medical therapy for a period of
Papatsoris, A. | Sarica, K.
Review | 2012 | Urological Research40 ( 6 ) , pp.639 - 646
The last decade flexible ureteroscopy has progressed from an awkward diagnostic procedure with limited visualization to a precise surgical intervention allowing access to the entire collecting system. In this review, we present the current status and future perspectives of the ureterorenoscopic management of urolithiasis and nonstone- related upper tract pathologies. © Springer-Verlag 2012.
Sarica, K. | Eryildirim, B. | Yencilek, F. | Kuyumcuoglu, U.
Article | 2009 | Urology73 ( 5 ) , pp.1003 - 1007
Objectives: To evaluate the possible role of being overweight on stone-forming risk factors in children. Methods: A total of 94 children (43 boys and 51 girls, male/female ratio 1:1.8) who were taking no medication or dietary modifications before treatment were included in the study. After a detailed stone disease history, the systolic and diastolic blood pressures were precisely measured and recorded for all patients. The body mass index, 24-hour urine values, and serum stone-forming risk parameters were evaluated in 44 overweight (17 boys and 27 girls; group 1) and 50 normal (26 boys and 24 girls; group 2) children. The results of . . . each group were compared using the Wilcoxon rank sum test. Results: The evaluation of the stone-forming risk factors in both groups revealed that the overweight status might be responsible for the increased excretion of these substances in such children. Most of the children in group 1 demonstrated hypocitraturia and hyperoxaluria (9/44, 20.5%) compared with the patients in group 2. Although the mean urinary oxalate level was 0.74 ± 0.81 mg/kg/24 h for boys and 0.69 ± 0.72 mg/kg/24 h for girls in group 1, relatively lower values were noted in group 2 (0.42 ± 0.52 and 0.45 ± 0.57 mg/kg/24 h for the boys and girls, respectively). Similarly, the children in group 1 had elevated mean urinary calcium and lower citrate excretion compared with the group 2 patients. Conclusions: Overweight status in children might be associated with an elevated risk of stone formation in both sexes owing to the alterations in urine composition. Obese children could be more prone to stone formation, and they should be evaluated and followed up for this aspect. Crown Copyright © 2009 Daha fazlası Daha az
Yencilek, F. | Erturhan, S. | Cangüven, Ö. | Erol, B. | Koyuncu, H. | Göktaş, C. | Sarica, K.
Article | 2009 | Turk Uroloji Dergisi35 ( 4 ) , pp.298 - 303
Objective: The aim of this study was to determine the effect of indomethacin, an anti-inflammatory agent, on apoptosis and crystal deposition developing as a consequence of tubular cell injury induced by hyperoxaluria in an animal model. Materials and methods: Fifty New Zealand rabbits were divided into 3 groups. The first 2 groups were fed with hyperoxaluric diet and Group 3 was the control group with no supplementary procedure or treatment. While the animals in Group 1 were given only hyperoxaluric diet, Group 2 animals was applied indomethacin in addition to the hyperoxaluric diet. Animals were sacrificed at the early (7th day) a . . .nd late (28th day) periods and renal tis-sue specimens were sent for the pathological analysis of crystal deposition and apoptosis. Results: The presence and degree of crystal deposition were significantly less in the specimens obtained from indomethacin-treated group during both the early and late periods ( Daha fazlası Daha az
Öztürk, M.I. | Gürbüz, C. | Koca, O. | Sarica, K. | Şenkul, T. | Yildirim, A. | Eryildirim, B.
Article | 2010 | Turk Uroloji Dergisi36 ( 2 ) , pp.125 - 131
Objective: The prevalence of urinary system stone disease is 1-13% worldwide with a steady increase parallel to the increasing modern life style. Turkey is among the countries where the disease is endemic. In this study adequacy of technical equipment used in diagnosis and treatment of ureteral stone along with treatment approaches were evaluated. Materials and methods: A total of 106 urology residents and specialists practicing in 10 different urology departments of training hospitals in Istanbul were asked to fill a questionnaire to evaluate the adequacy of necessary equipment and the treatment approaches in terms of diagnosis and . . . treatment of ureteral calculi. Results: More than 6 patients per month have been evaluated by the 78% of physicians participated to the study. All physicians had rigid ureterorenoscope and pneumatic lithotriptor in their clinics. While plain radiography of urinary system was the inital imaging choice for 63% of these physicians for patients with renal colic; 14% of them stated that they have to use a different imaging technique other than they aimed due to technical availability. For medical expulsive treatment 90% of the doctors were using alpha-blockers among which tamsulosin was the most commonly preferred one. Conclusion: Technical systems necessary for an efficient ureteral stone management seems to be adequate in clinics of physicians involved in this study. Answers given to questions regarding the diagnosis and treatment of ureteral stones were generally compatible with the existing literature data Daha fazlası Daha az
Sarica, K. | Yencilek, F.
Review | 2008 | Archivio Italiano di Urologia e Andrologia80 ( 1 ) , pp.27 - 33
Experimental as well as clinical findings reported in the literature suggest that treatment with shock wave lithotripsy (SWL) causes renal parenchymal damage mainly by generating free radicals through ischaemia /reperfusion injury mechanism. Although SWL-induced renal damage is well tolerated in the majority of healthy cases with no permanent functional and/or morphologic side effects, a subset of patients with certain risk factors requires close attention on this aspect among which the ones with pre-existing renal disorders, urinary tract infection, previous lithotripsy history and solitary kidneys could be mentioned. It is clear t . . .hat in such patients lowering the number of shock waves (per session) could be beneficial and has been applied by the physicians as the first practical step of diminishing SWL induced parenchymal damage. On the other hand, taking the injurious effects of high energy shock wave (HESW) induced free radical formation on renal parenchyma and subsequent histopathologic alterations into account, physicians searched for some protective agents in an attempt to prevent or at least to limit the extent of the functional as well as the morphologic alterations. Among these agents calcium channel blocking agents (verapamil and nifedipine), antioxidant agents (allopurinol, vitamin E and selenium) and potassium citrate have been used to minimize these unestimated adverse effects. Additionally, therapeutic application of these agents on reducing stone recurrence particularly after SWL will gain more importance in the future in order to limit new stone formation in these cases. Lastly, as experimental and clinical studies have demonstrated, combination of anti-oxidants with free radical scavengers may provide superior renal protection against shock wave induced trauma. However, we believe that further investigations are certainly needed to determine the dose-response relationship between the damaging effects of SWL application and the protective role of these agents Daha fazlası Daha az
Erturhan, S. | Bayrak, O. | Sarica, K. | Seckiner, I. | Baturu, M. | Sen, H.
Article | 2013 | Urology81 ( 3 ) , pp.640 - 643
Objective: To evaluate the possible efficacy of an ?1 blocker (doxazosin) therapy on the management and disease course in pediatric patients with distal ureteral stones. Materials and Methods: A total of 45 patients (24 boys and 21 girls) with a single lower ureteral stone were included in the study program. Their age range was 3-15 years (mean 6.65 ± 3.78). The children were randomized into 2 main groups: group 1 (n = 21), who received only ibuprofen 20 mg/kg/d divided into 2 equal doses for pain control during follow-up; and group 2 (n = 24), who received, in addition to ibuprofen, 0.03 mg/kg/d doxazosin once daily, before bed. Re . . .sults: The stone expulsion rate was 28.5% (6 of 21) in group 1 and 70.8% (17 of 24) in group 2 (P = .001). The number of daily colic attacks and stone expulsion time clearly demonstrated the advantage of doxazosin, with a statistically significant diminished number of pain attacks (P = .04) and shorter stone expulsion period (P =.001). Stones <5 mm were expulsed at greater rates than stones 5-10 mm in group 2 (P =.046). Also children aged <6 years passed the stones with significantly greater rates than children aged ?7 years (P =.008). Conclusion: The use of ?-adrenergic blocker agents could have certain advantages in attempts to render children stone free within a shorter period, which would inevitably diminish the number of colic attacks and the need for analgesic usage. © 2013 Elsevier Inc. All Rights Reserved Daha fazlası Daha az