- Email: [email protected]
MP40-01 IS TAMSULOSIN EFFECTIVE AFTER SHOCKWAVE LITHOTRIPSY FOR PEDIATRIC RENAL STONES? A RANDOMIZED CONTROLLED STUDY
THE JOURNAL OF UROLOGYâ
Vol. 193, No. 4S, Supplement, Sunday, May 17, 2015
Pediatrics: Testis & Varicoceles, Stones Moderated Poster 40 Sunday, May 17, 2015
8:00 AM-10:00 AM
MP40-01 IS TAMSULOSIN EFFECTIVE AFTER SHOCKWAVE LITHOTRIPSY FOR PEDIATRIC RENAL STONES? A RANDOMIZED CONTROLLED STUDY Ahmed Shahat, Ahmad Elderwy, Ahmed Safwat*, Ahmed Badawy, Yasser Abdelsalam, Mohamed Sayed, Hisham Hammouda, Assiut, Egypt INTRODUCTION AND OBJECTIVES: To identify factors affecting renal stone clearance after shockwave lithotripsy (SWL) in children and to assess the effect of tamsulosin as an adjunctive therapy after SWL in children. METHODS: One-hundred and twenty children below the age of 14 years with unilateral single renal pelvic stone were included in prospective randomized controlled study. Children with branched stone, solitary kidney, previous ipsilateral renal surgery, ureteral stent, or marked hydronephrosis were excluded. All children were randomized into two equal groups and all underwent SWL for their stones. Tamsulosin (in a dose of 0.01 mg/kg once daily) was prescribed for group (A) children as adjunctive therapy after SWL in addition to non-steroidal anti-inflammatory drug. Children in group (B) received non-steroidal anti-inflammatory drug only. Renal ultrasonography was performed 3 and 6 weeks after SWL. Stone clearance was defined as no renal stone fragments or <3mm and no pelvicalyceal system dilation. Children underwent a second session of SWL if there were residual stone fragment(s). Multivariate analysis was used to identify factors affecting single session stone clearance. Stone clearance rates in both groups were compared. RESULTS: Our study included 69 boys and 51 girls with median age 3.5 years and median stone size 1.2 cm. Stones were located in the right kidney in 72 children and in the left kidney in 48. KUB film showed that stones were radio-opaque in 82 (64 faint) and radiolucent in 38. Median stone density was 426 HU on non-contrast CT scan. There was no statistically significant difference between group (A) and group (B) regarding stone and children criteria. Ninety-nine (82.5%) children achieved stone clearance after the first session (50 in group A and 49 in group B). All children in both groups were cleared of stones after the second session. There was no statistically significant difference between single session stone clearance rates in either groups (p¼0.81). On multivariate analysis using logistic regression, tamsulosin intake as an adjunctive therapy after SWL had no statistically significant relation to single session clearance rate (p¼0.65). Smaller stone size (p¼0.016) and radio-opaque stones (p¼0.019) were the only significant factors. CONCLUSIONS: Stone size and radio-opacity are the main factors affecting renal stone clearance after SWL in children. Tamsulosin as an adjunctive therapy after SWL does not seem to improve renal stone clearance in children. Source of Funding: none
MP40-02 IDENTIFICATION OF NATURALLY OCCURRING CALCIUMOXALATE BINDING PROTEINS IN HUMAN URINE THAT PREVENT CRYSTAL ADHESION IN AN IN VITRO MODEL OF KIDNEY STONE FORMATION Joel Koenig*, Scott Manson, Qiusha Guo, Katelynn Moore, Paul Austin, Saint Louis, MO INTRODUCTION AND OBJECTIVES: Approximately one-half of patients with renal calculi experience at least one recurrence. Most
e463
stones are composed of calcium oxalate and develop from a combination of urinary supersaturation, crystal adhesion to epithelial cells, and subsequent growth. Existing treatment protocols focus on altering urine concentrations, which presents challenges due to the idiopathic nature of many stones and the variety of underlying factors. In this study, we examine the hypothesis that there are naturally occurring urinary proteins capable of binding calcium oxalate crystals, promoting their clearance, and preventing stone formation. Elucidating these interactions may provide novel therapies. METHODS: Calcium oxalate monohydrate (COM) crystals and fluorescently-labeled derivatives (COM-FITC) were synthesized in vitro. Stone formation was modeled in vitro by assessing the adhesion of COM-FITC crystals to confluent monolayers of inner medullary collecting duct (IMCD) epithelial cells. Affinity chromatography was used to isolate calcium oxalate-binding proteins from human urine. RESULTS: COM and COM-FITC crystals synthesized in vitro exhibited the typical prismoidal morphology of urinary crystals. Incubation of IMCD cells with COM-FITC crystals resulted in rapid binding to the cell surface with high affinity. The addition of urinary proteins purified from human urine inhibited COM-FITC binding by 76.2%. Furthermore, urinary proteins inhibited the growth of COM crystals in a free solution approximating urine composition by 53.5%. In using affinity chromatography to isolate calcium oxalate-binding proteins, we found that this technique was highly specific as only 16.6% of urinary proteins exhibited calcium oxalate-binding activity. The bound fraction was eluted, purified by electrophoresis, and four prominent proteins were identified (97 kD, 69 kD, 56 kD, 45 kD). CONCLUSIONS: This study demonstrates that naturally occurring urinary proteins bind to calcium oxalate crystals and inhibit their adhesion to the renal epithelium. We have isolated four calcium oxalate-binding proteins that are highly expressed in human urine. By characterizing the oxalate-binding domains in these proteins, it may be possible to design peptide-based therapies for preventing crystal adhesion and promoting oxalate clearance. Additionally, measuring the levels of these protective urinary proteins in patients may provide a means of stratifying patients and guiding treatment decisions. Source of Funding: This research was supported by grants from the NIH/NIDDK (5R01DK096177) and Midwest Stone Institute to PA and from the National Kidney Foundation to SM.
MP40-03 TRANS-SCROTAL NEAR INFRARED SPECTROSCOPY IN THE EMERGENCY DEPARTMENT TO DIAGNOSE TESTICULAR TORSION IN PEDIATRIC PATIENTS PRESENTING WITH ACUTE SCROTUM Bruce Schlomer*, Dallas, TX; Melise Keays, Ottowa, Canada; Gwen Grimsby, Dallas, TX; Candace Granberg, Rochester, MN; Daniel DaJusta, Columbus, OH; Berk Bergu, Ankar, Turkey; Lauren Ostrov, Kunj Sheth, Martinez Hill, Emma Sanchez, Rong Huang, Clanton Harrison, Micah Jacobs, Helim Hennes, Linda Baker, Dallas, TX INTRODUCTION AND OBJECTIVES: A rapid and reliable means to discern testis torsion from other causes of acute scrotum in children would aid emergency department (ED) care and may obviate the need for testicular ultrasound (TUS). In this study the testicular tissue saturation of oxygen (StO2) measured by trans-scrotal nearinfrared spectroscopy (NIRS) was assessed as a diagnostic test for pediatric testicular torsion. METHODS: From 2013-2014, males with acute scrotum >2 months and <18 years old were prospectively enrolled in this NIH clinical trial. ED NIRS StO2 readings were obtained for affected and contralateral control normal testes and did not impact clinical care. Testis torsion was diagnosed by history, physical exam and TUS and confirmed at surgery. The utility of NIRS to diagnose testis torsion in pediatric patients in the ED was described using receiver operating
Vol. 193, No. 4S, Supplement, Sunday, May 17, 2015
Pediatrics: Testis & Varicoceles, Stones Moderated Poster 40 Sunday, May 17, 2015
8:00 AM-10:00 AM
MP40-01 IS TAMSULOSIN EFFECTIVE AFTER SHOCKWAVE LITHOTRIPSY FOR PEDIATRIC RENAL STONES? A RANDOMIZED CONTROLLED STUDY Ahmed Shahat, Ahmad Elderwy, Ahmed Safwat*, Ahmed Badawy, Yasser Abdelsalam, Mohamed Sayed, Hisham Hammouda, Assiut, Egypt INTRODUCTION AND OBJECTIVES: To identify factors affecting renal stone clearance after shockwave lithotripsy (SWL) in children and to assess the effect of tamsulosin as an adjunctive therapy after SWL in children. METHODS: One-hundred and twenty children below the age of 14 years with unilateral single renal pelvic stone were included in prospective randomized controlled study. Children with branched stone, solitary kidney, previous ipsilateral renal surgery, ureteral stent, or marked hydronephrosis were excluded. All children were randomized into two equal groups and all underwent SWL for their stones. Tamsulosin (in a dose of 0.01 mg/kg once daily) was prescribed for group (A) children as adjunctive therapy after SWL in addition to non-steroidal anti-inflammatory drug. Children in group (B) received non-steroidal anti-inflammatory drug only. Renal ultrasonography was performed 3 and 6 weeks after SWL. Stone clearance was defined as no renal stone fragments or <3mm and no pelvicalyceal system dilation. Children underwent a second session of SWL if there were residual stone fragment(s). Multivariate analysis was used to identify factors affecting single session stone clearance. Stone clearance rates in both groups were compared. RESULTS: Our study included 69 boys and 51 girls with median age 3.5 years and median stone size 1.2 cm. Stones were located in the right kidney in 72 children and in the left kidney in 48. KUB film showed that stones were radio-opaque in 82 (64 faint) and radiolucent in 38. Median stone density was 426 HU on non-contrast CT scan. There was no statistically significant difference between group (A) and group (B) regarding stone and children criteria. Ninety-nine (82.5%) children achieved stone clearance after the first session (50 in group A and 49 in group B). All children in both groups were cleared of stones after the second session. There was no statistically significant difference between single session stone clearance rates in either groups (p¼0.81). On multivariate analysis using logistic regression, tamsulosin intake as an adjunctive therapy after SWL had no statistically significant relation to single session clearance rate (p¼0.65). Smaller stone size (p¼0.016) and radio-opaque stones (p¼0.019) were the only significant factors. CONCLUSIONS: Stone size and radio-opacity are the main factors affecting renal stone clearance after SWL in children. Tamsulosin as an adjunctive therapy after SWL does not seem to improve renal stone clearance in children. Source of Funding: none
MP40-02 IDENTIFICATION OF NATURALLY OCCURRING CALCIUMOXALATE BINDING PROTEINS IN HUMAN URINE THAT PREVENT CRYSTAL ADHESION IN AN IN VITRO MODEL OF KIDNEY STONE FORMATION Joel Koenig*, Scott Manson, Qiusha Guo, Katelynn Moore, Paul Austin, Saint Louis, MO INTRODUCTION AND OBJECTIVES: Approximately one-half of patients with renal calculi experience at least one recurrence. Most
e463
stones are composed of calcium oxalate and develop from a combination of urinary supersaturation, crystal adhesion to epithelial cells, and subsequent growth. Existing treatment protocols focus on altering urine concentrations, which presents challenges due to the idiopathic nature of many stones and the variety of underlying factors. In this study, we examine the hypothesis that there are naturally occurring urinary proteins capable of binding calcium oxalate crystals, promoting their clearance, and preventing stone formation. Elucidating these interactions may provide novel therapies. METHODS: Calcium oxalate monohydrate (COM) crystals and fluorescently-labeled derivatives (COM-FITC) were synthesized in vitro. Stone formation was modeled in vitro by assessing the adhesion of COM-FITC crystals to confluent monolayers of inner medullary collecting duct (IMCD) epithelial cells. Affinity chromatography was used to isolate calcium oxalate-binding proteins from human urine. RESULTS: COM and COM-FITC crystals synthesized in vitro exhibited the typical prismoidal morphology of urinary crystals. Incubation of IMCD cells with COM-FITC crystals resulted in rapid binding to the cell surface with high affinity. The addition of urinary proteins purified from human urine inhibited COM-FITC binding by 76.2%. Furthermore, urinary proteins inhibited the growth of COM crystals in a free solution approximating urine composition by 53.5%. In using affinity chromatography to isolate calcium oxalate-binding proteins, we found that this technique was highly specific as only 16.6% of urinary proteins exhibited calcium oxalate-binding activity. The bound fraction was eluted, purified by electrophoresis, and four prominent proteins were identified (97 kD, 69 kD, 56 kD, 45 kD). CONCLUSIONS: This study demonstrates that naturally occurring urinary proteins bind to calcium oxalate crystals and inhibit their adhesion to the renal epithelium. We have isolated four calcium oxalate-binding proteins that are highly expressed in human urine. By characterizing the oxalate-binding domains in these proteins, it may be possible to design peptide-based therapies for preventing crystal adhesion and promoting oxalate clearance. Additionally, measuring the levels of these protective urinary proteins in patients may provide a means of stratifying patients and guiding treatment decisions. Source of Funding: This research was supported by grants from the NIH/NIDDK (5R01DK096177) and Midwest Stone Institute to PA and from the National Kidney Foundation to SM.
MP40-03 TRANS-SCROTAL NEAR INFRARED SPECTROSCOPY IN THE EMERGENCY DEPARTMENT TO DIAGNOSE TESTICULAR TORSION IN PEDIATRIC PATIENTS PRESENTING WITH ACUTE SCROTUM Bruce Schlomer*, Dallas, TX; Melise Keays, Ottowa, Canada; Gwen Grimsby, Dallas, TX; Candace Granberg, Rochester, MN; Daniel DaJusta, Columbus, OH; Berk Bergu, Ankar, Turkey; Lauren Ostrov, Kunj Sheth, Martinez Hill, Emma Sanchez, Rong Huang, Clanton Harrison, Micah Jacobs, Helim Hennes, Linda Baker, Dallas, TX INTRODUCTION AND OBJECTIVES: A rapid and reliable means to discern testis torsion from other causes of acute scrotum in children would aid emergency department (ED) care and may obviate the need for testicular ultrasound (TUS). In this study the testicular tissue saturation of oxygen (StO2) measured by trans-scrotal nearinfrared spectroscopy (NIRS) was assessed as a diagnostic test for pediatric testicular torsion. METHODS: From 2013-2014, males with acute scrotum >2 months and <18 years old were prospectively enrolled in this NIH clinical trial. ED NIRS StO2 readings were obtained for affected and contralateral control normal testes and did not impact clinical care. Testis torsion was diagnosed by history, physical exam and TUS and confirmed at surgery. The utility of NIRS to diagnose testis torsion in pediatric patients in the ED was described using receiver operating