- Email: [email protected]
LAPAROENDOSCOPIC SINGLE SITE (LESS) DONOR NEPHRECTOMY: FEASIBILITY AND TECHNIQUE
THE JOURNAL OF UROLOGY®
Vol. 181, No. 4, Supplement, Wednesday, April 29, 2009
741
2046
2047
TRANSURETHRAL INJECTION THERAPY WITH CARBONCOATED BEADS (DURASPHERE®) FOR TREATMENT OF RECURRENT PYELONEFRITIS IN KIDNEY TRANSPLANT PATIENTS WITH VESICO-URETERAL REFLUX TO THE ALLOGRAFT
HEPATOCYTE GROWTH FACTOR PROLONGS ALLOGRAFT SURVIVAL WITH MAINTENANCE OF TREG POPULATION IN MHCINBRED CLAWN MINIATURE SWINE
Ioannis M Antonopoulos*, Affonso C Piovesan, Renato Falci, Jr, Hideki Kanashiro, Miguel Srougi, William C Nahas, Sao Paulo, Brazil INTRODUCTION AND OBJECTIVE: Recurrent pyelonefritis (RP) due to vesico-ureteral reflux (VUR) to the transplant kidney (KTx) impacts significantly on patient and graft outcomes. Many bulking agents have been tried to correct VUR. Our goal was to study for the first time the safety and efficacy of carbon-coated beads (Durasphere®, Boston Scientific Corporation, USA) subureteral injection to treat VUR in KTx with RP. METHODS: A prospective protocol was established between June 2004 and July 2008 to treat 8 patients (26 episodes of RP). The bladder was partialy filled to visualize the ureter. The needle was placed at the 6 o’clock position and Durasphere® was injected in the submucosa to coapt the ureteral orifice. A mean of 1.6±0.7 ml (1-3ml) was used. VCUG was performed to verify VUR absence and 40mg furosemide was given to discard obstruction. Patients were discharged the next day. The follow-up consisted of physical examination, urinary cultures and VCUG. RESULTS: Demographics are depicted in table I.The mean number of RP was 3.25±1.6 (1 to 6). The procedure was well tolerated without complications or KTx function deterioration. The mean age was 38.8±13.8 years (23-65). The mean follow-up was 18.2±15.7 months (352). Six patients (75%) were free of RP. Two of them had no VUR and 4 cases developed G II VUR (preop. G IV 3 cases; G III, 1 case). In one case, recurrent cystitis made a second treatment necessary. One of the remaining patients had 6 RP before treatment in a period of 3 years and only 2 RP after treatment in 2 years of follow-up. The other patient presented with a new infection after 5 months. One case had a duplex KTx with VUR to both renal units and was treated in the same manner. The clinical success rate (patients free of RP during follow-up) was 75%. The overall success rate (patients free RP plus the case in which the frequency of RP was considerably reduced) was 87.5%. CONCLUSIONS: Durasphere® is a safe and effective to treat patients with RP secondary to VUR to the KTx with an overall success rate of 87.5%. Endoscopic injection should be considered first line treatment for this situation. A second treatment may be necessary. Table I. Treatment details and outcomes PATIENT
1
2
5
6
7
8
AGE
31
23 65 44 26
43
50
42
DONOR
3
4
Hiroaki Nishimura*, Manei Oku, Masayoshi Okumi, Hisashi Sahara, Kentaro Setoyama, Wunimenghe Oriyanhan, Akira Shimizu, Kazuhiko Yamada, Kagoshima, Japan INTRODUCTION AND OBJECTIVE: We have previously reported that 12 days of FK506 facilitates the induction of tolerance to fully allogeneic kidneys in MGH miniature swine. The aims of this study are (1) to determine whether the same regimen facilitates the induction of tolerance to fully allogeneic kidneys in DNA-typed MHC-inbred CLAWN miniature swine; and, if not, (2) whether hepatocyte growth factor (HGF) has beneficial effects on graft functions. METHODS: 9 CLAWN miniature swine received fully MHC mismatched kidneys with 12 days (days 0-11) of FK506 with blood levels (35-45ng/ml) sufficient to induce tolerance in the MGH miniature swine kidney model. 5 recipients received FK506 alone (Group 1) and four received FK506 with either 7 days (0.03mg/kg/day) or 14 days (0.015mg/ kg/day) of HGF starting at day 11 (Group 2) infused through a catheter placed in the renal graft artery. RESULTS: In contrast to our previous report in MGH miniature swine, no animal treated with FK506 alone (Group 1) became tolerant despite using an identical protocol. These recipients developed either a severe acute rejection crisis (Cre >9mg/dl) or complete rejection within 3 weeks post KTx. In contrast, all four recipients that received HGF (Group 2) maintained stable renal function in the first 2 months, although grafts were eventually rejected beyond day 80. Although creatinine levels were similar between the groups immediately after discontinuing FK506 (1.9 mg/dl Group 1 vs. 1.8 mg/dl Group 2 at day 13), there was a significant difference in the creatinine levels 7 days after cessation of FK506 (8.2 mg/dl Group 1 vs. 1.9 Group 2 at day 18, p=0.008). Notably, a marked decrease in the percentage of CD4+CD25+Foxp3+ cells in the peripheral blood during the induction period was seen in Group 1, while HGF treated recipients maintained this population. CONCLUSIONS: This study demonstrates: (1) 12 days of highdose FK506 failed to induce tolerance across full MHC mismatched barriers in CLAWN miniature swine; (2) a short-course of HGF inhibited acute rejection and was associated with higher levels of CD4+CD25+Foxp3+ Tregs. These data suggest that CLAWN miniature swine may be a more stringent large animal model to test pre-clinical tolerance protocols and that a short-course of HGF prolongs renal allograft function and may either augment or maintain Treg cells. This is the first demonstration of the immunoprotective effect of HGF in a large animal model and suggests that HGF may be useful as an adjunct to induce tolerance by regulatory mechanisms.
LRD CD CD CD CD LRD LNRD LRD
interval KTx/Treat.
77
88 106 31 37
RACE
W
B
A
W
B
SEX
F
M
F
M
F
preop VUR grade
3
3
4
4
INFEC. NUMER
3
4
4
TREATMENTS
1
1
1
INJECTED VOLUME
1
1
postop VUR grade
1
INFECT. POST TREATMENT FOLLOW-UP
10
Source of Funding: Japanese Society for the Promotion of Science, Grant-in-Aid for Scientific Research (A-19209043 and B-19390422)
19
238
W
W
M
F
F
2048
2
3
3
4
LAPAROENDOSCOPIC SINGLE SITE (LESS) DONOR NEPHRECTOMY: FEASIBILITY AND TECHNIQUE
2
6
2
1
4
1
1
1
1
2
2
3
1
2
2
1
2
2
2
0
0
0
0
1
0
0
0
2
0
0
0
5
13 13 13 28
15
3
52
KTx, kidney transplant; VUR, reflux; CD, cadaveric; LR, living related; LNR, living non related
Source of Funding: None
Mohamed A Atalla*, Soroush Rais-Bahrami, Sero Andonian, Amin S Herati, Sylvia Montag, Lee Richstone, Louis R Kavoussi, New Hyde Park, NY INTRODUCTION AND OBJECTIVE: As laparoscopy becomes a standard approach in many urologic procedures, research strives to make minimally invasive surgery less invasive. This is particularly pertinent when live organ donation for transplantation is concerned. A primal goal for such procedures is to offer the least morbidity and time away from work while offer the best functional and cosmetic result for live organ donors. The widespread acceptance for laparoscopic donor nephrectomy could be at least partially attributed to these benefits. In an attempt at further improving these benefits, we developed a technique for and investigated the feasibility of true LaparoEndoscopic Single Site
742
THE JOURNAL OF UROLOGY®
(LESS) donor nephrectomy. METHODS: Four healthy patients were electively scheduled for kidney donation. Preoperative screening and preparation was completed as per our Transplant Center protocol. The operative technique utilized a modified flank position. Pneumoinsufflation was obtained using a Veress needle. A single 5cm transverse Pfannensteil incision was made. Two 5mm Anchorports (Surgiquest; Orange, CT) and one 12mm trocar were placed through separate fascial punctures within the single incision site. A flexible-tip laparoscope (LTF Series, Olympus Surgical; Orangeburg, NY) and flexible instruments (Realhand, Novare; Cupertino, CA) were used in addition to standard laparoscopic instruments. Laparoscopic donor nephrectomy technique was duplicated via a single operative site. The fascial puncture sites were joined and the kidney was extracted in a large Endocatch bag through the same incision for immediate transplantation. RESULTS: The patients’ mean age was 42. Mean operative time was 171 minutes. Mean warm ischemia time was 4.75 minutes. Estimated blood loss was 100 ml in each case and no transfusion were needed. Mean serum Creatinine was 1.025 preoperatively and 1.575 postoperatively. Mean hospital stay was 2.5 days (mode of 2 days). There were no intraoperative or postoperative complications. CONCLUSIONS: LESS donor nephrectomy is feasible by replicating laparoscopic donor nephrectomy techniques with the advent of flexible-tip laparoscopes and flexible instruments. Our technique describes the exclusive use of a single site for introduction of the instruments and extraction of the harvested kidney, without the needed for any other ports. A prospective randomized trial is needed to evaluate if the technique offers equivalent functional results, and superior recovery and cosmesis when compared to laparoscopic donor nephrectomy. Source of Funding: None
2049 EVALUATION OF TRANSPLANT KIDNEY RENAL FUNCTION WITH NEW ULTRASOUND MODALITY Shuo-Meng Wang*, Taipei, Taiwan INTRODUCTION AND OBJECTIVE: The power Doppler (PD) ultrasound can be applied to examine the blood flow of graft kidney noninvasively. A novel renal vascular perfusion index (RVPI), defined as PDVI max /PDVI min , was used to analyze the renal perfusion. METHODS: Between Aug 2007 and Aug 2008, fifty nine kidney transplants with stable renal function were enrolled in this study. Philip HDI 5000 was used to evaluate renal cortex with power Doppler where vascular tree image including interlobar,arcuate and interlobular vessels among different site of kidney with at least 3 cardiac cycles were recorded. (Figure 1) Data also included several resistance index at different kidney location. Clinical parameters include serum creatinine, age, sex and body weight. Power Doppler vascular index (PDVI) is defined as the percentage of color pixel in the region of interest (ROI). Analysis uses ‘Renal Vascularity Index Quantification software’, designed by Angiogenesis Research Center, National Taiwan University. RESULTS: The RVPI mean and medium values have significant correlation with estimated creatinine clearance including Cockcroft-Gault formula and Modification of Diet in Renal Disease (MDRD). (Table1) However, resistance index don’t. And creatinine CONCLUSIONS: This new index has proved its application for renal function examination among renal allograft patients. This is the first model developed in clinics which can examine renal perfusion and correlate with renal function by using non-invasive ultrasonography.
Vol. 181, No. 4, Supplement, Wednesday, April 29, 2009
In 59 cases with stable renal function, RVPI correlates well with eCCR ( Cockcroft-Gault and MDRD) RImean N=59 RVPImean Cre 0.40 0.14 P-value 0.00 0.37 Cockcroft-Gault -0.35 -0.30 P-value 0.00* 0.05 MDRD -0.34 -0.30 P-value 0.00* 0.06 *P<0.05 is considered significant difference
Source of Funding: None
2050 IDENTIFICATION OF SPECIFIC PROTEIN PATTERN IN URINE FOR EARLY DETECTION OF REJECTION AFTER KIDNEY TRANSPLANTATION Beatrice Stubendorff, Rico Pilchowski, Thomas Steiner, Undine Ott, Joerg Schubert, Olaf Reichelt, Gunther Wolf, Kerstin Junker*, Jena, Germany INTRODUCTION AND OBJECTIVE: The diagnosis of acute rejection can only be made by renal biopsy, which is costly, invasive, inconvenient, and carries a small risk of complications. Furthermore, it may not detect early changes because renal function does not always correlate with the histologic alterations. In order to define specific proteomic patterns for early detection of rejection we investigated urine samples from patients after transplantation with and without rejection by ProteinChip technology. METHODS: Thirty-two urine samples from patients with or without rejection after kidney transplantation were analyzed by SurfaceEnhanced Laser desorption/Ionization Time-of-Flight Mass Spectrometry (SELDI-TOF-MS) using 2 different chip arrays (Q10, IMAC C30). Bioinformatic data analysis was performed using the Fuzzy c-means method for clustering and the relevance index according to Kiendl. In a second step, results were evaluated by analyzing a second test set (32 samples with or without rejection). Furthermore, 16 samples obtained during the first 10 days after transplantation were analyzed. RESULTS: Bioinformatic analysis resulted in a rule base which allowed for differentiation between samples with or without rejection with sensitivity of 94% and specificity of 75%. Sensitivity and specificity after evaluation of the test set were 94% and 88%, respectively. The defined protein pattern of rejection was already found immediately after transplantation in 6 out of 8 patients. Specificity was 88%. CONCLUSIONS: The ProteinChip technology allows for the differentiation between patients with and without rejection with high sensitivity and specificity. It was possible to define specific protein pattern in urine from patients with confirmed rejection. Results were highly reproducible in a second test set. Diagnosis of rejection seems possible very early after transplantation based on the defined protein patterns. Source of Funding: None
Vol. 181, No. 4, Supplement, Wednesday, April 29, 2009
741
2046
2047
TRANSURETHRAL INJECTION THERAPY WITH CARBONCOATED BEADS (DURASPHERE®) FOR TREATMENT OF RECURRENT PYELONEFRITIS IN KIDNEY TRANSPLANT PATIENTS WITH VESICO-URETERAL REFLUX TO THE ALLOGRAFT
HEPATOCYTE GROWTH FACTOR PROLONGS ALLOGRAFT SURVIVAL WITH MAINTENANCE OF TREG POPULATION IN MHCINBRED CLAWN MINIATURE SWINE
Ioannis M Antonopoulos*, Affonso C Piovesan, Renato Falci, Jr, Hideki Kanashiro, Miguel Srougi, William C Nahas, Sao Paulo, Brazil INTRODUCTION AND OBJECTIVE: Recurrent pyelonefritis (RP) due to vesico-ureteral reflux (VUR) to the transplant kidney (KTx) impacts significantly on patient and graft outcomes. Many bulking agents have been tried to correct VUR. Our goal was to study for the first time the safety and efficacy of carbon-coated beads (Durasphere®, Boston Scientific Corporation, USA) subureteral injection to treat VUR in KTx with RP. METHODS: A prospective protocol was established between June 2004 and July 2008 to treat 8 patients (26 episodes of RP). The bladder was partialy filled to visualize the ureter. The needle was placed at the 6 o’clock position and Durasphere® was injected in the submucosa to coapt the ureteral orifice. A mean of 1.6±0.7 ml (1-3ml) was used. VCUG was performed to verify VUR absence and 40mg furosemide was given to discard obstruction. Patients were discharged the next day. The follow-up consisted of physical examination, urinary cultures and VCUG. RESULTS: Demographics are depicted in table I.The mean number of RP was 3.25±1.6 (1 to 6). The procedure was well tolerated without complications or KTx function deterioration. The mean age was 38.8±13.8 years (23-65). The mean follow-up was 18.2±15.7 months (352). Six patients (75%) were free of RP. Two of them had no VUR and 4 cases developed G II VUR (preop. G IV 3 cases; G III, 1 case). In one case, recurrent cystitis made a second treatment necessary. One of the remaining patients had 6 RP before treatment in a period of 3 years and only 2 RP after treatment in 2 years of follow-up. The other patient presented with a new infection after 5 months. One case had a duplex KTx with VUR to both renal units and was treated in the same manner. The clinical success rate (patients free of RP during follow-up) was 75%. The overall success rate (patients free RP plus the case in which the frequency of RP was considerably reduced) was 87.5%. CONCLUSIONS: Durasphere® is a safe and effective to treat patients with RP secondary to VUR to the KTx with an overall success rate of 87.5%. Endoscopic injection should be considered first line treatment for this situation. A second treatment may be necessary. Table I. Treatment details and outcomes PATIENT
1
2
5
6
7
8
AGE
31
23 65 44 26
43
50
42
DONOR
3
4
Hiroaki Nishimura*, Manei Oku, Masayoshi Okumi, Hisashi Sahara, Kentaro Setoyama, Wunimenghe Oriyanhan, Akira Shimizu, Kazuhiko Yamada, Kagoshima, Japan INTRODUCTION AND OBJECTIVE: We have previously reported that 12 days of FK506 facilitates the induction of tolerance to fully allogeneic kidneys in MGH miniature swine. The aims of this study are (1) to determine whether the same regimen facilitates the induction of tolerance to fully allogeneic kidneys in DNA-typed MHC-inbred CLAWN miniature swine; and, if not, (2) whether hepatocyte growth factor (HGF) has beneficial effects on graft functions. METHODS: 9 CLAWN miniature swine received fully MHC mismatched kidneys with 12 days (days 0-11) of FK506 with blood levels (35-45ng/ml) sufficient to induce tolerance in the MGH miniature swine kidney model. 5 recipients received FK506 alone (Group 1) and four received FK506 with either 7 days (0.03mg/kg/day) or 14 days (0.015mg/ kg/day) of HGF starting at day 11 (Group 2) infused through a catheter placed in the renal graft artery. RESULTS: In contrast to our previous report in MGH miniature swine, no animal treated with FK506 alone (Group 1) became tolerant despite using an identical protocol. These recipients developed either a severe acute rejection crisis (Cre >9mg/dl) or complete rejection within 3 weeks post KTx. In contrast, all four recipients that received HGF (Group 2) maintained stable renal function in the first 2 months, although grafts were eventually rejected beyond day 80. Although creatinine levels were similar between the groups immediately after discontinuing FK506 (1.9 mg/dl Group 1 vs. 1.8 mg/dl Group 2 at day 13), there was a significant difference in the creatinine levels 7 days after cessation of FK506 (8.2 mg/dl Group 1 vs. 1.9 Group 2 at day 18, p=0.008). Notably, a marked decrease in the percentage of CD4+CD25+Foxp3+ cells in the peripheral blood during the induction period was seen in Group 1, while HGF treated recipients maintained this population. CONCLUSIONS: This study demonstrates: (1) 12 days of highdose FK506 failed to induce tolerance across full MHC mismatched barriers in CLAWN miniature swine; (2) a short-course of HGF inhibited acute rejection and was associated with higher levels of CD4+CD25+Foxp3+ Tregs. These data suggest that CLAWN miniature swine may be a more stringent large animal model to test pre-clinical tolerance protocols and that a short-course of HGF prolongs renal allograft function and may either augment or maintain Treg cells. This is the first demonstration of the immunoprotective effect of HGF in a large animal model and suggests that HGF may be useful as an adjunct to induce tolerance by regulatory mechanisms.
LRD CD CD CD CD LRD LNRD LRD
interval KTx/Treat.
77
88 106 31 37
RACE
W
B
A
W
B
SEX
F
M
F
M
F
preop VUR grade
3
3
4
4
INFEC. NUMER
3
4
4
TREATMENTS
1
1
1
INJECTED VOLUME
1
1
postop VUR grade
1
INFECT. POST TREATMENT FOLLOW-UP
10
Source of Funding: Japanese Society for the Promotion of Science, Grant-in-Aid for Scientific Research (A-19209043 and B-19390422)
19
238
W
W
M
F
F
2048
2
3
3
4
LAPAROENDOSCOPIC SINGLE SITE (LESS) DONOR NEPHRECTOMY: FEASIBILITY AND TECHNIQUE
2
6
2
1
4
1
1
1
1
2
2
3
1
2
2
1
2
2
2
0
0
0
0
1
0
0
0
2
0
0
0
5
13 13 13 28
15
3
52
KTx, kidney transplant; VUR, reflux; CD, cadaveric; LR, living related; LNR, living non related
Source of Funding: None
Mohamed A Atalla*, Soroush Rais-Bahrami, Sero Andonian, Amin S Herati, Sylvia Montag, Lee Richstone, Louis R Kavoussi, New Hyde Park, NY INTRODUCTION AND OBJECTIVE: As laparoscopy becomes a standard approach in many urologic procedures, research strives to make minimally invasive surgery less invasive. This is particularly pertinent when live organ donation for transplantation is concerned. A primal goal for such procedures is to offer the least morbidity and time away from work while offer the best functional and cosmetic result for live organ donors. The widespread acceptance for laparoscopic donor nephrectomy could be at least partially attributed to these benefits. In an attempt at further improving these benefits, we developed a technique for and investigated the feasibility of true LaparoEndoscopic Single Site
742
THE JOURNAL OF UROLOGY®
(LESS) donor nephrectomy. METHODS: Four healthy patients were electively scheduled for kidney donation. Preoperative screening and preparation was completed as per our Transplant Center protocol. The operative technique utilized a modified flank position. Pneumoinsufflation was obtained using a Veress needle. A single 5cm transverse Pfannensteil incision was made. Two 5mm Anchorports (Surgiquest; Orange, CT) and one 12mm trocar were placed through separate fascial punctures within the single incision site. A flexible-tip laparoscope (LTF Series, Olympus Surgical; Orangeburg, NY) and flexible instruments (Realhand, Novare; Cupertino, CA) were used in addition to standard laparoscopic instruments. Laparoscopic donor nephrectomy technique was duplicated via a single operative site. The fascial puncture sites were joined and the kidney was extracted in a large Endocatch bag through the same incision for immediate transplantation. RESULTS: The patients’ mean age was 42. Mean operative time was 171 minutes. Mean warm ischemia time was 4.75 minutes. Estimated blood loss was 100 ml in each case and no transfusion were needed. Mean serum Creatinine was 1.025 preoperatively and 1.575 postoperatively. Mean hospital stay was 2.5 days (mode of 2 days). There were no intraoperative or postoperative complications. CONCLUSIONS: LESS donor nephrectomy is feasible by replicating laparoscopic donor nephrectomy techniques with the advent of flexible-tip laparoscopes and flexible instruments. Our technique describes the exclusive use of a single site for introduction of the instruments and extraction of the harvested kidney, without the needed for any other ports. A prospective randomized trial is needed to evaluate if the technique offers equivalent functional results, and superior recovery and cosmesis when compared to laparoscopic donor nephrectomy. Source of Funding: None
2049 EVALUATION OF TRANSPLANT KIDNEY RENAL FUNCTION WITH NEW ULTRASOUND MODALITY Shuo-Meng Wang*, Taipei, Taiwan INTRODUCTION AND OBJECTIVE: The power Doppler (PD) ultrasound can be applied to examine the blood flow of graft kidney noninvasively. A novel renal vascular perfusion index (RVPI), defined as PDVI max /PDVI min , was used to analyze the renal perfusion. METHODS: Between Aug 2007 and Aug 2008, fifty nine kidney transplants with stable renal function were enrolled in this study. Philip HDI 5000 was used to evaluate renal cortex with power Doppler where vascular tree image including interlobar,arcuate and interlobular vessels among different site of kidney with at least 3 cardiac cycles were recorded. (Figure 1) Data also included several resistance index at different kidney location. Clinical parameters include serum creatinine, age, sex and body weight. Power Doppler vascular index (PDVI) is defined as the percentage of color pixel in the region of interest (ROI). Analysis uses ‘Renal Vascularity Index Quantification software’, designed by Angiogenesis Research Center, National Taiwan University. RESULTS: The RVPI mean and medium values have significant correlation with estimated creatinine clearance including Cockcroft-Gault formula and Modification of Diet in Renal Disease (MDRD). (Table1) However, resistance index don’t. And creatinine CONCLUSIONS: This new index has proved its application for renal function examination among renal allograft patients. This is the first model developed in clinics which can examine renal perfusion and correlate with renal function by using non-invasive ultrasonography.
Vol. 181, No. 4, Supplement, Wednesday, April 29, 2009
In 59 cases with stable renal function, RVPI correlates well with eCCR ( Cockcroft-Gault and MDRD) RImean N=59 RVPImean Cre 0.40 0.14 P-value 0.00 0.37 Cockcroft-Gault -0.35 -0.30 P-value 0.00* 0.05 MDRD -0.34 -0.30 P-value 0.00* 0.06 *P<0.05 is considered significant difference
Source of Funding: None
2050 IDENTIFICATION OF SPECIFIC PROTEIN PATTERN IN URINE FOR EARLY DETECTION OF REJECTION AFTER KIDNEY TRANSPLANTATION Beatrice Stubendorff, Rico Pilchowski, Thomas Steiner, Undine Ott, Joerg Schubert, Olaf Reichelt, Gunther Wolf, Kerstin Junker*, Jena, Germany INTRODUCTION AND OBJECTIVE: The diagnosis of acute rejection can only be made by renal biopsy, which is costly, invasive, inconvenient, and carries a small risk of complications. Furthermore, it may not detect early changes because renal function does not always correlate with the histologic alterations. In order to define specific proteomic patterns for early detection of rejection we investigated urine samples from patients after transplantation with and without rejection by ProteinChip technology. METHODS: Thirty-two urine samples from patients with or without rejection after kidney transplantation were analyzed by SurfaceEnhanced Laser desorption/Ionization Time-of-Flight Mass Spectrometry (SELDI-TOF-MS) using 2 different chip arrays (Q10, IMAC C30). Bioinformatic data analysis was performed using the Fuzzy c-means method for clustering and the relevance index according to Kiendl. In a second step, results were evaluated by analyzing a second test set (32 samples with or without rejection). Furthermore, 16 samples obtained during the first 10 days after transplantation were analyzed. RESULTS: Bioinformatic analysis resulted in a rule base which allowed for differentiation between samples with or without rejection with sensitivity of 94% and specificity of 75%. Sensitivity and specificity after evaluation of the test set were 94% and 88%, respectively. The defined protein pattern of rejection was already found immediately after transplantation in 6 out of 8 patients. Specificity was 88%. CONCLUSIONS: The ProteinChip technology allows for the differentiation between patients with and without rejection with high sensitivity and specificity. It was possible to define specific protein pattern in urine from patients with confirmed rejection. Results were highly reproducible in a second test set. Diagnosis of rejection seems possible very early after transplantation based on the defined protein patterns. Source of Funding: None