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Featured researches published by P. Nunes.


Transplantation Proceedings | 2011

Surgical complications in 2000 renal transplants

P. Eufrásio; B. Parada; P. Moreira; P. Nunes; S. Bollini; A. Figueiredo; A. Mota

INTRODUCTIONnRenal transplantation is the best treatment for end-stage renal disease. In the last years, we have seen improvements in immunosuppressive treatment, which have allowed patients to experience a better quality of life and graft survival. Nevertheless, surgical complications remain important problems that increase morbidity, mortality, costs, and hospitalization. Our purpose was to evaluate surgical complications among a large series of 2000 renal transplantations.nnnPATIENTS AND METHODSnWe retrospectively analyzed all surgical complications among 2000 renal transplants performed between June 1980 and March 2010 in our department.nnnRESULTSnAmong 318 (15.9%) surgical complications, 4.8% of patients had urologic problems. Ureteral stenosis and fistula, stent obstruction, and ureteral necrosis occurred in 2.7%, 1.8%, 0.1%, and 0.2% of patients, respectively. Vascular complications reported in 2.7% of patients included arterial or venous thrombosis (1.0% or 0.4%), both arterial and venous thrombosis (0.1%), renal infarction (0.1%), renal artery aneurysm (0.1%) as well as arterial stenosis (0.5%), kinking (0.4%), or dissection (0.1%). Other complications, not specifically related with transplantation surgery, occurred in 4.4% of patients.nnnCONCLUSIONnRenal transplantation is a safe surgery by experienced teams. Our rates of surgical complications were within those reported by other series. A meticulous surgical technique is mandatory to prevent them. Prompt diagnosis and management are required to prevent graft damage and patient morbidity.


Transplantation Proceedings | 2014

Kidney Retransplantation: Removal or Persistence of the Previous Failed Allograft?

P. Dinis; P. Nunes; L. Marconi; F. Furriel; B. Parada; P. Moreira; A. Figueiredo; C. Bastos; A. Roseiro; V. Dias; F. Rolo; F. Macário; A. Mota

A significant percentage of patients with failed renal graft are candidates for retransplantation. The outcomes of retransplantation are poorer than those of primary transplantation and sensitization is documented to be a major reason. The management of a failed allograft that is not immediately symptomatic is still very controversial. The aim of this study was to determine the impact of the failed allograft nephrectomy on a subsequent transplantation and its importance in the sensitization. We performed a retrospective analysis of the local prospective transplantation registry of the outcome of 126 second kidney transplantations among 2438 transplantations performed in our unit between June 1980 and March 2013, comparing those who underwent allograft nephrectomy prior to retransplantation with those who retained the failed graft. Primary endpoints were graft and patient survival. The levels of panel-reactive antibodies (PRA) and rate of acute rejections on retransplantation outcomes were also studied. Among the 126 patients who underwent a second renal transplantation, 76 (60.3%) had a prior graft nephrectomy (Group A), whereas 50 (39.7%) kept their failed graft (Group B). Group A showed significantly more positive PRA levels when compared with the other group (38% vs 10%; Pxa0< .001), as measured before the most recent transplantation, and a higher rate of acute rejection (19% vs 5.6%; Pxa0= .016). There were 28 (36%) renal allograft losses for Group A and 18 (36%) for those who had not had transplantectomy (Pxa0= not significant [NS]). One-, 3-, and 5-year graft survival rates were 96.6%, 90.7%, and 83.4%, respectively, in Group A and 95%, 82%, and 68.4%, respectively, in Group B, with no statistical differences (Pxa0= .19). Five-year actuarial patient survival rates in the 2 groups was 89.3% and 82.8%, respectively (Pxa0= .55). Multivariate analysis showed that PRA level and delayed graft function (DGF) had a statistically significant influence on graft survival (Pxa0= .028; odds ratio [OR]xa0= 1.029; and Pxa0= .024; ORxa0= 8.6), irrespective of whether the patient had graft nephrectomy or not. The allosensitization indicated by PRA increases after transplantectomy and leads to a higher incidence of acute rejection after retransplantation. Nephrectomy of failed allograft does not seem to significantly influence the survival of a subsequent graft. The decision to remove or retain a failed graft in the context of retransplantation should thus be based on known clinical indications for the procedure.


Transplantation proceedings | 2013

Renal transplantation with donors older than 70 years: does age matter?

L. Marconi; A. Figueiredo; L. Campos; P. Nunes; A. Roseiro; B. Parada; A. Mota

PURPOSEnThe need for organs for renal transplantation has encouraged the use of grafts from increasingly older donors. Studies of transplantation results with donors older than 70 years are sparse. The main purpose of this study is to compare the results of transplantation with donors older and younger than 70 years old.nnnMETHODSnThis retrospective study included 1233 consecutive deceased-donor renal transplantations performed between January 1, 2001, and December 31, 2011. We compared outcomes of grafts from donors older than 70 years (group ≥ 70; n = 82) versus donors younger than 70 years (group < 70; n = 1151).nnnRESULTSnUnivariate analysis of pretransplantation data showed statistically significant differences (P < .05) among the following variables for the group < 70 and group ≥ 70, respectively: recipient age (46 ± 13 versus 61 ± 5 years), donor age (44 ± 16 versus 73 ± 3 years), donor male gender (69.4% versus 47.6%), use of antibody induction immunosuppression (51.7% versus 70.7%), and HLA compatibilities (2.4 versus 2). The group ≥ 70 showed increased postoperative minor complications: bleeding (8.5% versus 3.4%; P = .017), lymphocele formation (3.7% versus 0.5%; P = .011), and incisional hernia (2.4% versus 0.2%; P < .001). Regarding transplantation results, we observed that mean serum creatinine was significantly lower among group < 70, at 1, 3, 6, 12, 24, and 60 months after transplantation (P < .05). Cumulative graft survival at 1, 3, and 4 years was 90%, 85%, and 83% in the group < 70 versus 87%, 79%, and 72% in the group ≥ 70. In the subgroup of recipients younger than 60 years, we did not verify statistically significant differences in allograft survival between group ≥ 70 and group < 70. Using Cox regression for survival analysis, we verified that donor age was not an independent risk factor for graft failure.nnnCONCLUSIONSnThe group of patients who received kidneys from donors younger than 70 years achieved better transplantation outcomes. Nevertheless, kidneys from older donors represent an excellent alternative for older recipients.


Transplantation proceedings | 2013

Ureteric Stent in Renal Transplantation

G. Gomes; P. Nunes; D. Castelo; B. Parada; R. Patrão; C Bastos; A. Roseiro; A. Mota

INTRODUCTIONnSeveral techniques can be used to accomplish the ureteroneocystostomy in kidney transplantation. A ureteral catheter is a prophylactic measure to avoid urological complications (UC) of stenosis and/or fistula. In this study we evaluate the influence of using a ureteral stent upon the rate of UC in renal transplantation.nnnPATIENTS AND METHODSnRetrospective review of 2061 kidney transplants (75 living and 1986 cadaveric donors) for 1360 male and 684 female recipients, from July 14, 1991, to January 13, 2012, with a minimum follow-up of 6 months A double J stent (JJ) was used in 1890 an external tumor (ET) catheter in 52 and no catheter (NC) in 119 cases.nnnRESULTSnMean recipient age was 44.66 ± 13.66 years. UC occurred in 5.9% among which ET showed 17.3%, 8.4% for NC, and 5.4% for JJ (P < .0005). Urological complications were more frequent when surgery duration exceeded 3 hours (8.8% vs 5.3% ≤ 3 hours; P = .003), using older donors organs (P = .048) and with higher donor weight (P = .009). No differences were observed related to recipient age, gender, or weight; donor gender; pretransplant dialysis time; cold ischemia time; type of donor (living vs cadaveric); number of HLA matches; or initial immunosuppression (mammalian target of rapamycin inhibitor vs other). On multivariate analysis, donor weight (odds ratio [OR]: 1.023; P = .015), use of a JJ vs ET (OR: 0.280; P = .005), and surgery time exceeding 3 hours (OR: 3.270; P < .0005) were independently associated with UC.nnnCONCLUSIONSnCatheterization of the urinary anastomosis with a JJ was associated with fewer UC. This is especially important for grafts from heavier donors. The use of an external catheter which was associated with an high rate of UC, should be avoided.


Transplantation Proceedings | 2017

Prostate Cancer in Renal Transplant Recipients: Diagnosis and Treatment

J. Carvalho; P. Nunes; P. Dinis; H. Antunes; B. Parada; L. Marconi; P. Moreira; A. Roseiro; C. Bastos; F. Rolo; V. Dias; A. Figueiredo

BACKGROUNDnWe currently know that prostate cancer (Pca) risk is reduced in patients undergoing kidney transplantation. However, its impact and treatment are not widely studied.nnnMETHODSnThis was a retrospective study of male patients submitted to kidney transplantation in our center from 1980 to 2016 evaluating incidence, treatment, and follow-up of Pca in our population.nnnRESULTSnIn 1805 patients undergoing kidney transplantation, 20 men were diagnosed with Pca, leading to an incidence of 1.1%. Median age at renal transplantation was 53.4 years with a median age at diagnosis of Pca of 61.2 years. Initial median prostate-specific antigen (PSA) was 6 ng/mL and Gleason score was 7 (3xa0+ 4) in about 50% of cases. Bone metastasis developed in 10% and no visceral metastases were diagnosed. The majority of patients were submitted to radical prostatectomy and bilateral pelvic lymph node dissection. Some other cancers occurred in these patients such as skin and pulmonary cancers. In 35% of the cases, the graft was lost. The main cause of patient death was cardiovascular. The mean graft survival was about 14 years. The majority of patients are alive with functioning grafts (65%).nnnCONCLUSIONnIn our center the clinical incidence of Pca in patients undergoing kidney transplantation is 1.1% and surgical treatment seems to be a good initial option.


Transplantation Proceedings | 2011

Renal Transplantation in Recipients over 65 Years Old

P. Eufrásio; P. Moreira; B. Parada; P. Nunes; A. Figueiredo; Rui Alves; F. Macário; A. Mota

BACKGROUND AND PURPOSEnOlder patients on hemodialysis have become candidates for renal transplantation, particularly in the period of increasing numbers of marginal donors. The purpose of this study was to evaluate short-term and long-term results of renal transplantation among recipients ≥65 years old for comparison with these in younger patients.nnnPATIENTS AND METHODSnWe retrospectively studied 1,796 renal transplantations performed between June 1991 and May 2010, dividing the sample into 2 groups: ≥65 years old (n = 89) versus <65 years old (n = 1,707).nnnRESULTSnThe mean ages were 42.17 and 67.45 years for the younger and older groups, respectively. Time of pretransplantation dialysis was significantly greater among the older group (52.76 vs 47.69 mo). There were no differences between the 2 groups regarding donor age, donor renal function, or cold ischemia times. After a mean follow-up of 73.37 versus 39.73 months for the younger versus older groups, respectively, we observed differences in initial graft function, with a greater rate of delayed graft function in the ≥65 group (28.1% vs 17.8%), and in acute rejection rate, which was higher among the younger group (19.4% vs 10.1%). Initial creatinine was better for the older group (1.71 vs 2.10 mg/dL), but similar between the groups at 10 years. Graft and patient survivals at 1, 5, and 10 years were lower among the older group. When analyzing graft survival censored for death with a functioning kidney, there were no differences between the younger and older groups: It was at 1, 5, and 10 years, namely 93.6% versus 90.6%, 87% versus 80.8%, and 76.7% versus 70.1%, respectively.nnnCONCLUSIONSnSelected recipients ≥65 years of age show good outcomes of transplantation.


Transplantation Proceedings | 2013

Does Multiorgan Versus Kidney-Only Cadaveric Organ Procurement Affect Graft Outcomes?

D. Castelo; L. Campos; P. Moreira; F. Furriel; B. Parada; P. Nunes; A. Figueiredo; A. Mota

INTRODUCTIONnThe majority of kidney grafts in most European countries still come from deceased donors who provide other organs. We analyzed whether multiorgan procurement portends a worse functional outcome compared with kidney-only harvesting.nnnMETHODSnWe performed a retrospective analysis of 1043 consecutive brain-dead donor kidney transplantations performed at a single academic institution from September 2002 to June 2011. The graft outcomes using kidney-only donors (n = 243) were compared with multiorgan donor grafts (n = 800) analyzing donor age, gender, cause of death, duration of mechanical ventilation, renal function, and cold ischemic interval. We compared delayed graft function and serum creatinine values at 1, 3, 6, and 12 months posttransplantation as well as graft survivals. This methodology was also applied to the subset of expanded criteria donors: 179 kidney-only versus 474 multiorgan. The influence of donor variables on graft survival was also analyzed in a Cox regression model. Immunosuppressive regimens and preservation solutions were similar in both groups.nnnRESULTSnKidney-only donors were older than their multiorgan counterparts (53.1 versus 44.8, P < .0005) and predominantly male (76.5% versus 62.6% male donors, P < .0005). Other donor variables were comparable. Kidney-only donor grafts showed a slightly higher incidence of delayed function (27.2 versus 21.1%, P = .049), but the mean serum creatinine values were similar at all intervals. No differences were observed in 7-year graft survival: 80.7% versus 79.9%. Expanded criteria donor grafts showed overlapping results, except for a higher rate of donor oligoanuria and a lower 1-month mean creatinine among kidney-only donors. Multivariate analysis revealed that the number of harvested organs did not influence graft survival.nnnDISCUSSIONnImmediate and long-term outcomes of kidney grafts did not correlate with the number of organs harvested from the donor. The longer explantation time associated with multiorgan procurement did not seem to affect graft function.


Transplantation Proceedings | 2009

Kidney Transplantation With Corticosteroid-Free Maintenance Immunosuppression: A Single Center Analysis of Graft and Patient Survivals

R. Filipe; A. Mota; Rui Alves; C. Bastos; F. Macário; A. Figueiredo; A. Roseiro; B. Parada; H. Sá; P. Nunes; M. Bastos

The purpose of this study was to assess the impact of a corticosteroid-free maintenance immunosuppression on graft survival in kidney transplantation. We analyzed 79 patients who were transplanted between June 1, 2006 and May 31, 2007. We excluded hyperimmunized patients, second transplantations, living donors, and black recipients. Patients underwent induction with thymoglobulin or basiliximab, followed by treatment with mycophenolate mofetil (MMF), tacrolimus, and methylprednisolone. On the 5th day, the patients were divided into 2 groups: group A (n = 45) discontinued steroid therapy; group B (n = 34) continued prednisone therapy. We performed a comparative analysis of incidence of delayed graft function (DGF), acute rejection episodes (ARE), renal function at 6 and 12 months, graft and patient survivals, causes of graft loss, and mortality. The 2 groups were similar for donor, recipient, and graft characteristics. The incidences of DGF were 8.9% in group A and 14.7% in group B; those for ARE were 2.3% in group A and 13.8% in group B (P = .077). The mean serum creatinine levels at 6 and 12 months were similar. There were 8 graft losses: 3 in group A (3 deaths with functioning grafts) and 5 in group B (1 death, 3 vascular causes, 1 kidney nonfunction). The 4 deaths were due to infection (n = 3) or neoplasia (n = 1). Graft survivals at 1 year were 98% in group A and 85% in group B, and patient survivals were 98% and 97%, respectively. An immunosuppressive regimen using antibody induction and steroid-free treatment proved to be effective in low-risk patients.


Transplantation Proceedings | 2018

Pediatric Renal Transplantation: Evaluation of Long-Term Outcomes and Comparison to Adult Population

H. Antunes; B. Parada; E. Tavares-da-Silva; J. Carvalho; C. Bastos; A. Roseiro; P. Nunes; A. Figueiredo

BACKGROUNDnIn Europe, pediatric transplantation accounts for only about 4% of all kidney transplantations performed. The aim of our work is to evaluate the evolution of pediatric renal transplantation in our department over time, but also to compare this special population with the adult one.nnnMETHODSnWe evaluated all pediatric renal transplantations performed in our department between January 1981 and December 2016. We performed the analysis of clinical, analytical, and surgical factors to look for predictive factors of graft loss or decrease of survival. In addition, we performed a comparative study of pediatric and adult populations and an evaluation of the evolution of pediatric renal transplantation in our department over time.nnnRESULTSnWe evaluated 101 renal transplantations performed in patients younger than 18 years. Pediatric transplantations corresponded to 3.4% of all renal transplantations performed in our department. The rate of living donors was 12%. Donors of grafts for the pediatric population were significantly younger than in the adult population. The increase in donor age was associated with lower renal graft survival rates. Acute rejections were more frequent in the pediatric population. Eleven pediatric recipients (10.9%) died in the follow-up period. Renal graft survival in the pediatric population was 94.8%, 77.4%, and 66.5% at 1, 5, and 10 years, respectively. There was no significant difference in graft survival in the pediatric and adult population. The pediatric overall survival rate at 1, 5 and 10 years was 97.9%, 96.8%, and 91.9%, respectively.nnnCONCLUSIONnPediatric renal transplantation presents results identical to those identified in adults.


Transplantation Proceedings | 2015

Small Kidneys for Large Recipients: Does Size Matter in Renal Transplantation?

P. Dinis; P. Nunes; L. Marconi; F. Furriel; B. Parada; P. Moreira; A. Figueiredo; C. Bastos; A. Roseiro; V. Dias; F. Rolo; Rui Alves; A. Mota

BACKGROUNDnImbalance between transplanted renal mass and the metabolic demands of the recipient has been identified as a predictor of renal graft function. Multiple factors have been used to test this influence, but none of them is consensually accepted. The aim of this study is to evaluate the influence of the imbalance between transplanted renal mass and the metabolic needs of the recipient by analyzing the relationship between the ratio of the weight of the renal graft and the body weight of the recipient (Kw/Rw) on transplantation outcomes.nnnMETHODSnProspective observational study of 236 first and single cadaveric renal transplants in non-hyperimmunized recipients was conducted. Grafts were orthogonally measured and weighed immediately before implantation, and these measures were correlated with donor and recipient data. According to the Kw/Rw ratio, patients were divided into three groups: Kw/Rw < 2.8 (P25), Kw/Rw = 2.8-4.2, and Kw/Rw > 4.2 (P75). After a mean follow-up of 5.2 years, transplant outcomes (delayed graft function; acute rejections; and estimated 1-, 6-, 12-, 36-, and 60-month renal function, graft, and patient survivals) were evaluated and correlated in uni- and multivariate analyses with the Kw/Rw ratio.nnnRESULTSnMean values for graft dimensions were 109.47 × 61.77 × 40.07 mm and the mean weight was 234.63 g. Mean calculated volume was 145.64 mL. The mean Kw/Rw ratio was 3.65 g/kg. These values were significantly lower for female grafts (3.91 vs 3.24, P < .001). According to the Kw/Rw ratio groups, there were no differences on delayed graft function, acute rejection episodes, and estimated graft function at the defined times. The increase in estimated glomerular filtration rate by a mean of 3.6 mL/min between 1 and 6 months for patients with Kw/Rw < 2.8 was not statistically relevant when compared to the higher ratio group with a mean variation of -0.91 mL/min (P = .222). Graft survival rate at 5 years after transplantation was 79% in the Kw/Rw < 2.8 group and 82% in the Kw/Rw > 4.2 group (P = .538). Patient survival rate at 5 years after transplantation was 85% in the Kw/Rw < 2.8 group and 92% in the high ratio group (P = .381). Kw/Rw ratio was not an independent risk factor for transplant failure at 5.2 years in a multivariate logistic regression analysis. Irrespective of recipient weight, graft survival was significantly higher for grafts with volume or weight above the 50 percentile (vol > 134 mL, P = .011 or weight > 226 g, P = .016).nnnCONCLUSIONnThe imbalance between implanted renal mass and recipient metabolic demands does not seem to influence the functional outcomes and graft survival up to 60 months post-transplantation. Nevertheless, irrespective of recipient weight, graft survival is significantly higher for grafts with volume or weight above the 50 percentile.

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B. Parada

University of Coimbra

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A. Mota

University of Coimbra

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C. Bastos

University of Coimbra

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F. Rolo

University of Coimbra

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V. Dias

University of Coimbra

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