Which One Is the Best for Living Donation: A Multiple-Artery Left Kidney Nephrectomy or a Right Kidney Nephrectomy?

INTRODUCTION: The current approach in living-donor kidney transplant is to preserve the best kidney for the donor and harvest the contralateral one. Due to a shorter renal vein and a greater incidence of venous thrombosis, left kidneys are more frequently elected. Notwithstanding, arterial anatomy may be complex and thus render the transplantation procedure more difficult and prone to complications. OBJECTIVES: To analyze the outcomes after multiple-artery left kidney nephrectomy (MALKN) and right kidney nephrectomy (RKN). RESULTS: Seventy-three cases were performed from 1999 to 2017 in our institution: 34 MALKN and 39 RKN. The mean operative time was significantly longer in MALKN. Warm ischemia time, donor and receptor hospital stay, and postoperative complications did not differ between groups. There was a positive correlation between renal arteries' ostia distance in MALKN and the duration of warm ischemia period. There was no significant difference in the incidence of acute tubular necrosis, first-year variations in serum creatinine, and glomerular filtration rate between groups. Long-term graft survival did not significantly differ between groups. Three cases of vein thrombosis after RKN were reported with graft loss. CONCLUSION: The safety and efficacy of MALKN does not differ from RKN, although there appears to be a higher incidence of vein thrombosis after right kidney transplantation. Despite being technically more demanding, particularly in cases with distant artery ostia, MALKN could be a better option than RKN for living donation, expanding the available donor pool, although more studies are needed to affirm this conclusion.

Role of de novo donor-specific anti-HLA antibodies in kidney graft failure: A case-control study.

The role of de novo donor-specific anti-human leukocyte antigen (anti-HLA) antibodies (dnDSA) within the pathways leading to graft failure remains not fully understood. We investigated 56 patients who were transplanted between 2002 and 2014 with kidney graft failure (cases), for a possible association of development of dnDSA with graft failure. The 56 patients with failed transplants were matched with 56 patients with a functioning graft at present for the variables deceased or living donor, transplant number, transplant year, recipient age and gender, donor age and gender, dialysis vintage time, transplant induction therapy. All patients had at least one serum collected 1 year before failure (in cases) or end of follow-up (in controls). Cases and controls were very well-matched in several baseline characteristics. Post-transplant anti-HLA antibodies were found in 84% of cases and only 36% of controls (P < .001), with 54% of cases and 16% of controls (P < .001) having dnDSA at time of detection. Chronic active antibody-mediated rejection was significantly more common (P < .001) in patients with dnDSA (61% vs 12%), in 53 (47%) patients that had at least one graft biopsy performed during follow-up. dnDSA was a significant risk factor (odds ratio [OR] = 6.06; P = .003) for graft failure in a multivariable conditional logistic regression model. dnDSA as a time-dependent variable, was also an independent predictor [hazard ratio (HR) = 2.46; P = .002] of graft failure in a multivariable Cox regression analysis. In both statistical approaches, only dnDSA-II (OR = 11.90; P = .006) (HR = 2.30; P = .014) was significantly associated with graft failure. Post-transplant dnDSA was clearly associated with graft loss, particularly if against HLA class II antigens. dnDSA detection should be a tool for post-transplant monitoring of kidney graft recipients, allowing for the identification of those with a higher risk of graft failure.

Increase of allosensitization after a kidney graft failure: Predictors and effect on retransplantation outcomes / Aumento de la alosensibilización después de un fallo del injerto renal: predictores y efecto en los resultados del retrasplante

Patients who are candidates for a second kidney transplant (SKT) frequently have a higher level of panel reactive antibodies (PRA). We assessed the allosensitisation change after a first graft failure (GF), its predictors and impact on retransplantat outcomes. We retrospectively selected 140 adult patients who received a SKT. Recipient and donor characteristics were analyzed. We defined the delta PRA (dPRA) as the difference between peak PRA before the SKT and first one (cohort median value=+10%). Logistic regression analysis was used to determine risk factors for dPRA≥10% and acute rejection (AR) in the SKT. Univariable and multivariable Cox analysis was applied to assess independent predictors of second GF. Risk factors for dPRA≥10% at SKT were AR (OR=2.57; P=0.022), first graft survival <1 year (OR=2.47; P=0.030) and ABDR HLA mismatch (OR=1.38 per each mismatch; P=0.038). AR in the SKT was associated with dPRA≥10% (OR=2.79; P=0.047). Induction with a lymphocyte-depleting agent had a protective effect (OR=0.23; P=0.010). SKT survival was lower (P=0.008) in patients with a dPRA≥10% (75.6%, 60.5% in dPRA≥10%; 88.6%, 88.6% in dPRA<10% patients at 5 and 10 years, post-transplant respectively). Multivariable Cox regression showed that dPRA≥10% (HR=2.38, P=0.042), delayed graft function (HR=2.82, P=0.006) and AR (HR=3.30, P=0.001) in the SKT were independent predictors of retransplant failure. This study shows that an increased allosensitisation at retransplant was associated with the degree of HLA mismatch and led to poorer outcomes. De-emphasis of HLA matching in current allocation policies may be undesirable, particularly in patients with a higher chance of needing a SKT (AU)

Los pacientes candidatos a un segundo trasplante de riñón (STR) tienen a menudo un nivel superior de panel reactivo de anticuerpos (PRA). Evaluamos el cambio de alosensibilización después de un primer fracaso del injerto, sus predictores y repercusión en los resultados del retrasplante. Elegimos retrospectivamente a 140 pacientes adultos que recibieron un STR. Analizamos las características de los receptores y de los donantes. Definimos el delta PRA (dPRA) como la diferencia entre el pico de PRA antes del STR y el primero (cohorte mediana=+10%). Se aplicó análisis de regresión logística para determinar los factores de riesgo para dPRA≥10% y rechazo agudo (RA) en STR y análisis univariado y multivariado de Cox para evaluar predictores independientes de fallo del retrasplante. Los factores de riesgo para dPRA≥10% fueron: RA (OR=2,57; p=0,022), supervivencia del primero injerto menor a un año (OR=2,47; p=0,030) e incompatibilidad HLA ABDR (OR=1,38 por cada mismatch; p=0,038). El RA en el STR fue asociado con dPRA≥10% (OR=2,79; p=0,047). La inducción con un agente depletor de linfocitos tuvo un efecto protector (OR=0,23; p=0,010). La supervivencia del STR fue menor en pacientes con dPRA≥10% (75,6; 60,5% en dPRA≥10%; y 88,6; 88,6% en dPRA<10%; a los 5 y 10 años). La regresión multivariada de Cox mostró que dPRA≥10% (HR=2,38; p=0,042), función retardada de injerto(HR=2,82; p=0.006) y RA (HR=3,30; p=0,001) en STR fueron factores predictores independientes de fracaso en el retrasplante. Este estudio muestra que un incremento en la alosensibilización de retrasplante se ha asociado con el grado de incompatibilidad HLA y puede conducir a resultados más pobres en STR. La falta de énfasis en la compatibilidad de HLA en las políticas actuales de asignación puede no ser deseable, especialmente en pacientes con una mayor probabilidad de necesitar un STR (AU)

Ureteral Stenosis After Renal Transplantation-A Single-Center 10-Year Experience.

BACKGROUND: Kidney transplantation (KT) is the definitive treatment for ESRD. Ureteral stenosis (US) is one of the most common urologic complications and has been reported in 2.6%-15% of KTs. METHODS: We reviewed data for 973 consecutive KT procedures performed at our center from January 2004 to September 2014, with evaluation of US management and recurrence rate. RESULTS: The 973 KTs were performed with the use of the direct ureterovesical (UV) implantation Paquin technique, and the mean follow-up time was 44.3 ± 30.2 [range, 3-111] months. During this period, 33 cases of US (3.39%) were reported. The interval from KT to US diagnosis was 10.6 ± 23.0 (range, 0.5-98.0) months. The majority of the US cases were located in the distal ureter and UV junction (83.9%), with only 2 cases of middle ureter stenosis and 2 cases of ureteropelvic junction. Mean US length was 2.5 ± 1.9 (range, 1.0-10.0) cm. Surgical management and global and treatment-specific recurrence rates were reviewed. Primary surgical treatment recurrence rate was higher for the endoscopic approach, with a mean global time from treatment to US recurrence of 6.9 ± 16.3 (range, 0-65) months and a median of 2.0 months. Open surgical approach was the main recurrence treatment option (74%). There were 2 cases of graft loss. Success rate evaluation of overall and treatment-specific primary surgical management did not reveal significant differences (P > .05) according to stenosis length (<1.5, 1.5-3.0, or >3.0 cm), time between transplant and stenosis (≤3, 3-12, or >12 mo), or stenosis location (distal, middle, or upper ureter). However, there was clearly a trend to higher success rate in smaller stenosis (<1.5 cm) and early management (≤3 mo), particularly with the use of balloon dilation. CONCLUSIONS: US management should be decided on a case-by-case basis according to clinical characteristics, treatment-specific recurrence rate, and previous surgical options.

Low transplantability of 0 blood group and highly sensitized candidates in the Portuguese kidney allocation algorithm: quantifying an old problem in search of new solutions.

The impact of patient's biological differences in waiting time for kidney transplantation is well known and has been a subject of extensive debate and struggle in transplantation community. Our purpose was to evaluate patient's access to kidney transplantation in Portugal, regarding their degree of allosensitization and blood type. A retrospective cohort study including 1020 candidates for kidney transplantation between 01 January 2010 and 31 December 2011 in transplant unit Centro Hospitalar do Porto was performed. The deceased donor organ offer by blood type decreased with the calculated panel reactive antibody (cPRA) increase for A and B blood groups candidates, while in 0 blood group candidates, a significant reduction in organ offer was only observable in hypersensitized (HS) ones. As a consequence, the median waiting time was also significantly higher in 0 blood group patients, when compared to the remaining groups. However, waiting time increased extensively with cPRA regardless blood type, especially HS patients with increases of 368%, 632%, 486%, and 140% for blood groups A, B, AB, and 0, respectively, when compared to each blood group global median waiting time. Our study shows that important measures need to be undertaken in order to mitigate the huge disadvantage that HS and 0 blood type patients naturally have.

Effect of Different Sensitization Events on HLA Alloimmunization in Kidney Transplantation Candidates.

BACKGROUND: HLA alloimmunization is caused by sensitization events (SEs), such as transfusion, pregnancy, or previous organ transplantation, and the effects of particular SEs have not been thoroughly studied. Our aim was to evaluate how each SE affected HLA alloimmunization by considering Luminex assays. METHODS: Sera from 722 kidney transplantation candidates were screened per protocol by means of Luminex assays to determine the presence of anti-HLA class I/II antibodies; positive sera underwent single-antigen assay to determine the presence of specific antibodies against HLA A, B, C, DR, DQ, DP loci (positivity if median fluorescence intensity values were >1,000). The effect of each SE was analyzed considering only patients exposed to 1 kind of sensitization. RESULTS: In the 453 candidates with ≥1 SE, anti-HLA class I positivity rates were significantly higher in patients with previous transfusion (18.9%; P = .014), pregnancy (38.3%; P < .001) or transplant (75%; P < .001) compared with those with no SE (similar results for class II). The strength (median fluorescence intensity) of specific antibodies was significantly higher in patients with previous transplantation than in those with previous transfusion for HLA-A (8,017 vs 2,302; P = .02), HLA-B (7,765 vs 2,901; P = .018), and HLA-DR (9,835 vs 2,060; P = .003). Other anti-HLA antibody strengths were similar between patients with previous pregnancy or transplantation. CONCLUSIONS: Presence of any SE analyzed was associated with a higher prevalence of anti-HLA antibodies for class I ± II compared with nonsensitized patients. Transplantation had the strongest immunization effect on both classes, followed by pregnancy and then transfusion.

From Open to Laparoscopic Living-donor Nephrectomy: Changing the Paradigm in a High-volume Transplant Center.

In 1995, Ratner et al reported the first laparoscopic living-donor nephrectomy, and since then this approach is gradually replacing traditional open surgery. The learning curve of the procedure is still unclear and lessons taken from initial experience series are of utmost importance. We retrospectively analyzed our initial 50 living-donor laparoscopic nephrectomies, of which 90% were performed on the left side. Renal vascular variation occurred in 28% of donors. The median age and body mass index of the donors were 50 years (IQR 39-55) and 24.65 kg/m(2) (IQR 22.5-27.3), respectively. The median operative time and warm ischemia time were 160 minutes (IQR 141-178) and 240 seconds (IQR 210-280), respectively. Estimated blood loss was 60 mL (IQR 60-127.5). The serum creatinine of the receptors was 97.6 µmol/L (IQR 87.5-139.6) 1 month after transplant. Overall, there were 5 complications, including 2 (4%) open conversions, 1 (2%) incisional hernia, 1 (2%) graft loss, and 1 (2%) reintervention. The body mass index and the multiple arteries did not influence the operative time and warm ischemia time or the recipient's serum creatinine level. Along the series, there was a significant reduction in the operative time (Spearman ρ = -5.2; P < .001), but no significant differences were found for warm ischemia time, blood loss, or serum creatinine of the recipients (P > .05). Laparoscopic donor nephrectomy is a safe procedure in centers experienced in laparoscopic surgery; however, the learning curve plateau was not reached after the initial 50 cases.

Allograft nephrectomy: a single-institution, 10-year experience.

INTRODUCTION: Allograft nephrectomy (AN) is associated with a high number of surgical complications. Some authors advocate that early nephrectomy (<1 year) is associated with fewer complications. Intracapsular (ICAN) and extracapsular AN (ECAN) might have a different impact on allosensitization and surgical outcomes. Our goal was to compare surgical outcomes between early and late AN in our institution and to compare ICAN and ECAN in terms of surgical outcomes and panel reactive antibodies (PRA) variation. MATERIALS AND METHODS: Between January 2000 and October 2012, we performed 104 AN at our institution (32 early and 72 late). Comparisons between early and late AN, and, within the latter, between the 2 different techniques were sought. Statistical analysis was performed for sample description, group comparison and %PRA variation. RESULTS: Among the 104 patients with a mean age of 47.9 ± 14.2 years, 54 were men. Age, gender, body mass index, and number of previous transplants were similar between early and late AN and between ICAN and ECAN patients. Late AN was associated with less blood loss (293.4 ± 229.0 vs 414.3 ± 349.5 mL; P = .03), shorter hospital stay (12.8 ± 14.5 vs 26.8 ± 26.5; P < .05), and fewer complications (22.2% vs 59.3%; P < .05). The chance of being relisted for transplantation was similar (50.0% in early vs 59.7% in late AN; P = .7). When comparing ICAN and ECAN, there was no difference in surgical outcomes. The %PRA variation between the 2 techniques was comparable (-1.2 ± 10.6 ICAN vs -0.5 ± 15.9 ECAN; P = .8), as was the chance of being relisted for transplantation (60.5% ICAN vs 58.6% ECAN; P = .8). CONCLUSIONS: Early AN was associated with a greater number of surgical complications. Nevertheless, the number of AN patients returning to the active waiting list was similar between early and late AN groups. ICAN and ECAN had similar surgical and postoperative outcomes, although a bias may be present because some conversions from ECAN to ICAN occurred owing to technical issues. As in other studies, ICAN did not seem to affect allosensitization or jeopardize the chance of being relisted for transplant when compared with ECAN.

Pediatric kidney transplantation: a single center experience with 134 procedures.

Renal transplantation confers substantial benefits on children with end-stage renal disease (ESRD), including improved growth as well as longer and better quality of life. The aim of this study was to report our experience with 134 pediatric renal transplantations. Epidemiological and clinical data of all patients transplanted who were younger than 18 years between January 1984 and May 2012 were collected from our prospective database. One hundred twenty-four patients (44% female) underwent 134 renal transplantations. Renal insufficiency was secondary to urological obstructive uropathy (46%), nephropathy (34%), and other causes (20%). Mean age at the time of the surgery was 13 years. Mean time of ESRD was 25 months. One hundred seventeen patients (95%) received cadaveric renal allografts. Mean cold ischemia time was 1302 minutes. Mean donor age was 19.7 years. Mean length of hospital stay was 17 days. Mean follow-up was 122 months. Graft survivals at 5 and 10 years were 84.1 and 71.9%, respectively. Ninety-six percent of kidney recipients were alive; 71% with functioning allografts. Mean current glomerular filtration rate among functioning kidneys is 55 mL/min. Renal transplantation in the pediatric population is a good option for ESRD patients.

Urological complications after 134 pediatric kidney transplants: a single-center study.

The incidence of surgical complications after kidney transplantation has been reported to range from 1% to 33%. The aim of this work was to report surgical urological complications among our cohort of 134 pediatric kidney transplantations. Epidemiological and clinical data of all patients younger than 18 years transplanted between January 1984 and May 2012 were collected from our prospective database. Urologic complications and management are reported herein. One hundred twenty-four patients, including 44% females underwent 134 renal transplants. Median age at the time of the surgery was 13 years. Mean time of end-stage renal disease was 25 months. We identified 10 subjects (7.5%) with urological complications: 5 ureterovesical stenoses, 2 lymphoceles, and 3 lower ureteral fistulas. All of the renal allografts were obtained from cadaveric donors. Mean age of these patients at the time of transplantation was 13 years. Mean cold ischemia time was 1613 minutes. All the patients required surgical management. All patients with ureterovesical stenoses underwent ureteral reimplantation using a Boari flap; those with lymphoceles underwent open marsupialization; 2 with ureteral fistulas underwent reimplantation of the ureter, and the other patient's case required placement of a nephrostomy tube and an antegrade ureteral catheter. All patients were treated successfully. Mean follow-up time of cases with urological complications was 9.5 years. Currently, 60% has nonfunctioning allografts; the mean current glomerular filtration rate of the functioning renal allografts is 55 mL/min. Despite requiring surgical management, all patients were treated successfully. Prompt identification and treatment of any complication are critical for graft and patient survival.

Advantages of kidney transplant precocity in graft long-term survival.

BACKGROUND: Preemptive kidney transplantation (KT) or KT after a brief period on dialysis (<6 months) has been associated with better graft survival. Our study aimed to analyze the effect of an early KT on graft survival censored for patient death with functioning graft. METHODS: A total of 1,373 kidney-only transplantations, from both living and deceased donors, performed from 1983 to 2010 were retrospectively studied. We defined 2 groups: those with early KT (preemptive or within 6 months after dialysis initiation; n = 131) and non-early KT (n = 1,242). Survival curves for each group were calculated by Kaplan-Meier analysis and compared by log-rank test. The independent effect of early KT on censored graft survival was analyzed by a multivariate-adjusted Cox proportional regression model. RESULTS: The 5-, 10-, 15-, and 20-year censored graft survival rates were, respectively, 96%, 89%, 79%, and 79% among the early KT group, and 91%, 81%, 68%, and 49% among the non-early KT group (P = .024). Multivariate analysis showed the following to be independent predictors for censored graft failure: non-early KT (hazard ratio [HR] 2.58; P = .028), recipient age (HR 0.97; P < .001), donor age (HR 1.03; P < .001), recipient negative status for cytomegalovirus IgG (HR 1.44; P = .032), delayed graft function (HR 1.48; P = .013), and acute rejection event (HR 1.68; P = .002). CONCLUSIONS: Our results show that early KT can be an approach for the improvement of long-term graft survival.

The incidence of cancer and potential role of sirolimus immunosuppression conversion on mortality among a single-center renal transplantation cohort of 1,816 patients.

INTRODUCTION: The chronic use of immunosuppressive drugs in renal transplant recipients increases the risk of developing de novo malignancies. Herein we analyze the incidence of de novo tumors and the potential role of sirolimus to improve cancer-specific survival among a cohort at a single center. METHODS: This retrospective analysis of our 1,816 patients allografted between January 1983 and December 2009 sought subjects who developed de novo tumors. Epidemiological and clinical data were examined using Mann-Whitney and Pearson's chi-square or Fisher exact tests for statistical comparisons of continuous and categorical variables, respectively. Kaplan-Meier survival curves were used to determine cancer-specific survival according to type of neoplasia and immunosuppressive regimen, namely, conversion to sirolimus. RESULTS: One hundred patients (5.5%) were diagnosed with a de novo malignancy. The 110 different cancers were diagnosed at a median interval of 73 months after kidney transplantation. The overall cancer-specific survivals at 1 and 5 years after cancer diagnosis were 87.0% and 76.9%, respectively. The 15 patients converted to sirolimus showed no difference in survival. CONCLUSION: The observed frequencies of cancer in our center are consistent with the literature. Among our cohort, sirolimus did not significantly impact survival among subjects who had de novo malignancies.

Late venous thrombosis of renal allograft: two cases with different treatment and outcome

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Bone mineral density after simultaneous kidney-pancreas transplantation: four years follow-up of 57 recipients.

Bone disease and an high risk of fractures are major problems in transplantation. Among diabetic patients undergoing simultaneous kidney-pancreas (SKP) transplantation, there are few studies assessing long-term effects on bone mass. The aim of this study was to evaluate bone mineral density (BMD) over 4 years follow-up after SKP transplantation. Fifty-seven patients had 22.8 +/- 5.3 years of prior diabetes, 65% were female, and the overall mean age was 24.3 +/- 5.93 years. At the time of transplantation, the lumbar spine and femoral neck T-scores were -1.75 +/- 1.05 and -1.95 +/- 0.73, respectively; 28% of subjects had evidence of osteoporosis. One year after transplantation, 77.6% of patients displayed improved lumbar T-scores to -1.33 +/- 0.94 (P = .044) with stable femoral neck T-scores. Bone densitometry enhanced gradually through the 4 years follow-up: lumbar T-score to -1.04 +/- 0.67 (P = .004) and femoral neck T-score to -1.69 +/- 0.49 (P = .12). At year 4, no osteoporosis cases were detected but 86.7% of patients did not receive steroids in the immunosuppressive regimen. The graft function remained stable (serum creatinine, 1.2 mg/dL; fasting glucose, 87.7 mg/dL). During the follow-up, BMD improved more significantly at cortical sites. Our study reports a reduced prevalence of fractures (8.7%) compared with the literature, which could be related to a steroid-sparing protocol and/or aggressively treatment of osteoporosis.

Early sirolimus use with cyclosporine elimination does not induce progressive proteinuria.

Proteinuria has been reported in several papers after conversion from calcineurin inhibitors to Sirolimus (SRL), but this complication has not been analyzed in randomized clinical trials using de novo SRL. It is not known whether de novo use of SRL is a risk factor for proteinuria. We analyzed a series of patients included in a big multicenter randomized trial (RMR trial) corresponding to all patients in Spain and Portugal with respect to this issue. We retrospectively evaluated 24-hour proteinuria in all the patients during the study period (5 years postransplant) for comparison between treatment arms group A, continuous cyclosporine (CyA) + SRL and group B SRL with CyA elimination at 3 months postransplant. The elimination of CyA after the third month was not followed by significant changes in proteinuria. Nevertheless, during the last year of follow-up (between 48 and 60 months postransplant) an impressive increase in proteinuria was observed in group A. This surprising finding seemed to be a consequence of a protocol amendment that recommended CyA elimination in patients of group A, due to poorer results in the intermediate analysis of the trial. This fact suggests that the hemodynamic changes induced by elimination of the vasoconstrictor CyA might be responsible for the proteinuria but only in the long term probably when significant pathological lesions are already present. This finding argues for earlier conversion.