Ioannis M. Antonopoulos
University of São Paulo
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Urology | 2002
William Carlos Nahas; Eduardo Mazzucchi; Marco A. Arap; Ioannis M. Antonopoulos; Elias David Neto; Luiz Estevam Ianhez; Sami Arap
OBJECTIVES To assess the surgical and long-term results of renal transplantation in 25 patients with bladder dysfunction and augmentation cystoplasty. METHODS We retrospectively reviewed the evolution and surgical outcome of 25 renal transplants in 24 recipients with augmentation cystoplasty. The mean patient age at transplantation was 27.6 years. The etiology of bladder dysfunction was neurogenic bladder with detrusor hyperreflexia (11 patients), tuberculosis (5 patients), vesicoureteral reflux (4 patients), posterior urethral valves (3 patients), and interstitial cystitis (1 patient). Seventeen transplants were from living donors. Augmentation cystoplasty was performed before transplantation in 21 patients. The bowel segments used in the augmentation cystoplasty included ileum in 16, ileocecal segments in 2, and sigmoid in 5 patients. The donor ureter was anastomosed to the native bladder in 16 patients, to the bowel segment in 6, and to the native ureter in 3. RESULTS Twenty kidneys (80%) were functioning at a mean follow-up of 53.2 months (range 6 to 118). The mean serum creatinine was 1.56 mg/dL (range 0.7 to 2.6). Three patients died of unrelated causes and 1 of adenocarcinoma that originated at the vesicointestinal anastomosis. The actuarial graft survival at 1, 2, and 5 years was 96%, 92%, and 78%, respectively. Complications included symptomatic urinary infection, ureteral stenosis, and lymphocele. CONCLUSIONS Augmentation cystoplasty is a safe and effective method to restore function in noncompliant bladders. Renal transplantation can be performed safely after augmentation cystoplasty.
The Journal of Urology | 2001
Eduardo Mazzucchi; William Carlos Nahas; Ioannis M. Antonopoulos; Luis Estevam Ianhez; Sami Arap
PURPOSE We evaluate the incidence of incisional hernia after kidney transplantation, predisposing factors and the results of surgical repair with polypropylene mesh. MATERIALS AND METHODS We reviewed the records of 371 consecutive kidney transplants performed between April 1995 and February 2000. Patients with clinical signs of hernia at the transplant incision site were included in the study. Predisposing factors for incisional hernia were also reviewed. A prospective protocol of surgical correction was established using polypropylene mesh and patient outcome was studied. RESULTS We identified 14 patients (3.8%) with an incisional hernia at the transplant incision site. Hernias developed 3 to 840 days after transplant surgery and were significantly more common in white (p = 0.019) and cadaveric graft (p = 0.02) recipients. Predisposing factors in 11 cases included complications of transplant surgery in 7, bladder obstruction in 2, large polycystic kidneys in 1 and chronic pulmonary disease in 1. Surgical repair was performed by primary fascial approximation and polypropylene mesh reinforcement in 13 cases and by pre-peritoneal mesh placement in 1. Minor subcutaneous wound infection developed in 1 patient. No relapses were noted at a mean followup of 17.8 months. CONCLUSIONS In the majority of cases incisional hernia develops in the first 3 months after transplant surgery. The incidence is significantly higher in white patients and after cadaveric donor transplantation. Surgical complications of transplant surgery are important predisposing factors for incisional hernia after kidney transplantation. Surgical repair using polypropylene mesh is safe and effective in this group of patients.
Transplantation | 2006
Eduardo Mazzucchi; Alexandre Danilovic; Ioannis M. Antonopoulos; Afonso C. Piovesan; William Carlos Nahas; Antonio Marmo Lucon; Miguel Srougi
Background. We reviewed our experience with third, fourth, and fifth renal transplants performed by the extraperitoneal access. Methods. The charts of 21 third and subsequent transplants performed extraperitoneally were reviewed. Surgical aspects, the occurrence of rejection episodes, delayed graft function (DGF), graft and patient survival were evaluated and compared with 1560 first transplants in adults with nonmanipulated fossa performed in the same period. Results. Transfusion was necessary in 52% of the retransplants and in 5.7% of the first transplants (P<0.0001). Mean operative time was 327 min for retransplants and 212 min for first transplants (P<0.0001). Surgical complications occurred in 4 patients (19%): two arterial thrombosis and two ureteral obstructions. DGF occurred in 11 patients (52%) among retransplants and in 453 (29%) among first transplants (P=0.028). Acute rejection occurred in 7 (33.3%) retransplants and in 530 first transplant patients (33.9%). The mean serum creatinine among retransplant patients 30 days and one year after transplantation was 2.5 mg/dl and 1.8 mg/dl. One-year graft survival was 57.1% (75% for live and 46% for cadaver donors) for retransplants and 86% for first transplant patients (P<0.0001). Conclusion. Third and subsequent transplants performed extraperitoneally are more time-consuming and require more transfusions in the perioperative period. A higher but acceptable incidence of arterial thrombosis and urinary obstruction were observed. One-year graft survival was better with live donor grafts, but was still lower when compared with first transplants using the same surgical technique.
Urology | 2008
Ioannis M. Antonopoulos; William Carlos Nahas; Affonso C. Piovesan; Renato Falci; Hideki Kanashiro; Gilberto A. Alvarez; Miguel Srougi
OBJECTIVE To investigate the feasibility of radical retropubic prostatectomy (RRP) in renal transplant recipients with clinically localized prostate cancer. METHODS A prospective protocol was established between August 2004 and November 2007. In that period, 8 patients diagnosed with localized prostate cancer were submitted to RRP, and their clinicopathologic data were reviewed. RESULTS The mean age (+/- standard deviation) at surgery was 59.6 +/- 6.7 years (range, 49-67 years). All patients had T1C tumors, except for 1 with a T2A tumor. The mean preoperative prostate-specific antigen value was 4.5 +/- 1.8 ng/mL (range, 1.6-7.0 ng/mL). The mean interval between renal transplantation and RRP was 89.9 +/- 65.1 months (range, 40-209 months). The procedure was well tolerated without major complications, and all patients were discharged on the fifth postoperative day. There was no impairment to bladder descent caused by the presence of the allograft or the ureteroneocystostomy. Urethrovesical anastomosis was easily performed in all cases in the standard manner. Blood transfusion was needed in 2 patients (1 received 2 U and another 5 U of blood). The mean operative duration was 183 +/- 29.7 minutes (range, 150-240 minutes), the mean estimated blood loss was 656 +/- 576 mL (range, 100-2000 mL), and no deterioration of graft function was observed. All patients were followed, and the mean follow-up was 10.5 months (range, 2-30 months). Prostate-specific antigen was undetectable in all cases during this time frame. CONCLUSIONS Radical retropubic prostatectomy in renal transplant patients is safe, effective, and can be easily performed in the same manner as described by Walsh, regardless of the presence of the allograft. The only necessary technical modification is the avoidance of ipsilateral lymphadenectomy to prevent damage to the transplanted organ.
International Braz J Urol | 2006
Eduardo Mazzucchi; Guilherme L. Souza; Marcelo Hisano; Ioannis M. Antonopoulos; Affonso C. Piovesan; William Carlos Nahas; Antonio Marmo Lucon; Miguel Srougi
OBJECTIVES urinary fistula is a morbid complication after renal transplantation leading to graft losses and patient death. We review and update our data on urinary fistula after renal transplantation and the outcome after surgical and conservative management. MATERIALS AND METHODS the charts of 1046 renal transplants were reviewed. Transplants were performed through an extended inguinotomy; vascular anastomoses to the iliac vessels and urinary reconstruction accomplished through the Gregoir technique. Fistulae were diagnosed by urinary leaks through the incision or by the occurrence of a collection in the iliac fossa. Patient was treated surgically or conservatively according to the characteristics of the fistula and patient clinical status. RESULTS Thirty one fistulae were diagnosed (2.9%). Twenty nine leaks due to ureteral necrosis and 2 due to reimplantation fault. The incidence of leaks among cadaver and live donor transplants was 3.22% and 2.63%, respectively (p = 0.73). Among diabetic and non diabetic patients the incidence of urinary leaks was 6.4% and 2.6%, respectively (p = 0.049). Treatment consisted in anastomosis of the graft ureter or pelvis with the ureter of the recipient in 17 cases with success in 13 (76.5%). Prolonged bladder drainage was employed in 7 cases and the fistula healed in 4 (57%). Ureteral reimplantation was performed in 3 cases and did not work in any of them. Ureteral ligature plus nephrostomy was employed in two cases and worked in one (50%). Percutaneous nephrostomy and ureteral stenting with double J catheter were employed in one case each and worked in both. CONCLUSIONS The anastomosis of the graft ureter with the ureter of the recipient is a good method for treating urinary fistulae after renal transplantation when local and systemic conditions are good. Ureteral ligature associated to nephrostomy should be applied in cases of unfavorable local conditions or clinically unstable patients.
The Journal of Urology | 2000
William Carlos Nahas; Eduardo Mazzucchi; Ariel Gustavo Scafuri; Ioannis M. Antonopoulos; Elias David Neto; Luis Estevan Ianhez; Sami Arap
PURPOSE We present our experience with kidney transplantation in children weighing 20 kg. or less. Surgery was done via extraperitoneal access while preserving the peritoneal cavity intact with special attention given to technical feasibility and the complication rate. MATERIALS AND METHODS Included in our study were 46 children with a median age of 7 years weighing 20 kg. or less (mean 16.6), of whom 16 weighed less than 15 kg. (median 13.2). The 25 boys and 21 girls underwent a total of 49 kidney transplants, including 2 in 3 during the study. Donors were living related in 44 cases and cadaveric in 5. Surgical access was obtained by making a J-shaped pararectal incision in a curvilinear fashion from the symphysis pubis to near the costal border. RESULTS Mean hospital stay was 22.9 days (range 6 to 83) and mean followup was 55.8 months (range 12 to 131). All patients received water on day 1 and food on day 2 postoperatively. In 6 patients 7 surgical complications developed, including urinary fistula in 2, superficial wound infection in 2 and vascular complications in 3 (renal vein thrombosis, stenosis and renal artery kinking in 1 each). Only 1 graft was lost due to a surgical complication. CONCLUSIONS There are many advantages to using extraperitoneal access without an increase in surgical complications or technical difficulty. Absent gastrointestinal complications, an easier way to perform percutaneous biopsy, treatment of any surgical complication with no need for repeat laparotomy and the possibility of using the peritoneal cavity when dialysis is needed postoperatively are attractive justifications for extraperitoneal access.
International Braz J Urol | 2005
Alexandre Danilovic; Ioannis M. Antonopoulos; Jose Luis Borges Mesquita; Antonio Marmo Lucon
OBJECTIVES To evaluate the likelihood of retrograde double-J stenting in urgent ureteral drainage according to obstructing pathology. MATERIALS AND METHODS From July 2002 to January 2003, 43 consecutive patients with ureteral obstruction who needed urgent decompression were evaluated at our institution, where we performed a total of 47 procedures. Emergency was defined as ureteral obstruction associated with infection, obstructive acute renal failure, or refractory pain. Ureteral obstruction was defined as intrinsic and extrinsic based on etiology and evaluated by ultrasound. Patients submitted to previous double-J stenting were excluded. Failures in retrograde ureteral stenting were treated with percutaneous nephrostomy. Results were analyzed with Fishers exact test and regression analysis. RESULTS Failure in retrograde ureteral stenting occurred in 9% (2/22) and 52% (13/25) of the attempts in patients with intrinsic and extrinsic obstruction respectively (p < 0.001). Failures in stenting extrinsic obstructions occurred due to lack of identification of the ureteral meatus in 77% and impossibility of catheter progression in 23% (p < 0.05). All attempts of retrograde catheter insertion failed in obstructions caused by prostate or bladder pathologies (6/6). Inability to identify the ureteral meatus was the cause of all failures. CONCLUSION Retrograde double-J stenting has a low probability of success in extrinsic ureteral obstruction caused by prostate or bladder disease. Such cases might be best managed with percutaneous nephrostomy.
Nephrology Dialysis Transplantation | 2011
Elias David-Neto; Daisa Silva Ribeiro David; Giordano F. Ginani; Helcio Rodrigues; Patricia Soares Souza; Maria Cristina Ribeiro de Castro; Hideki Kanashiro; Fernando Saito; Renato Falci; Ioannis M. Antonopoulos; Afonso C. Piovesan; William Carlos Nahas
BACKGROUND Sensitized patients (pts) may develop acute antibody-mediated rejection (AMR) due to preformed donor-specific antibodies, undetected by pre-transplant complement-dependent cytotoxicity (CDC) crossmatch (XM). We hypothesized that C4d staining in 1-h post-reperfusion biopsies (1-h Bx) could detect early complement activation in the renal allograft due to preformed donor-specific antibodies. METHODS To test this hypothesis, renal transplants (n = 229) performed between June 2005 and December 2007 were entered into a prospective study of 1-h Bx and stained for C4d by immunofluorescence. Transplants were performed against a negative T-cell CDC-XM with the exception of three cases with a positive B-cell XM. RESULTS All 229 1-h Bx stained negative for C4d. Fourteen pts (6%) developed AMR. None of the 14 protocol 1-h Bx stained positive for C4d in peritubular capillaries (PTC). However, all indication biopsies-that diagnosed AMR-performed at a median of 8 days after transplantation stained for C4d in PTC. CONCLUSIONS These data show that C4d staining in 1-h Bx is, in general, not useful for the early detection of AMR when CDC-XM is negative.
Clinical Transplantation | 2001
Ioannis M. Antonopoulos; William Carlos Nahas; Eduardo Mazzucchi; Luiz Estevam Ianhez; Luiz Balthazar Saldanha; Sami Arap
Biopsy is the gold standard for the diagnosis of conditions affecting the function of renal allografts. Obtaining representative tissue in biopsies is critical but these procedures are associated with up to 9% of complications and 20% of inadequate material. Although ultrasound guidance allows perfect control of depth and location of the graft, there is controversy regarding the cost–benefit of its use and reports of unsuitable material in ultrasound‐guided biopsies are still high. Purpose: To compare ultrasound with the palpation method to guide biopsies in order to see if there is any difference between both methods and which one is better. Patients and methods: The casuistic consisted of 82 renal transplant patients (32 female and 50 male patients, age ranging between 5 and 64 yr; m=31.2 yr) randomized into two groups: GI, palpation‐guided; GII, ultrasound‐guided. Fifty‐six biopsies were performed in GI and 66 in GII. Results: Number of glomeruli, arcuate, and interlobar arteries and arterioles were compared in the two groups and were 503 (m=10) vs. 801 (m=12.9), 24 (m=0.5) vs. 38 (m=0.6), 104 (m=2.1) vs. 154 (m=2.5), and 174 (m=3.5) vs. 264 (4.3), respectively (p<0.05). Inadequate material for analysis in GI and GII was 7.1 and 7.6%, respectively (p=0.72). Conclusions: Although ultrasound guidance improves the number of glomeruli, arcuate, and interlobar arteries, as well as arterioles, compared with palpation‐guided biopsies, there is no difference in the rate of adequate material between the two methods.
Transplantation Proceedings | 2008
Afonso C. Piovesan; Antonio Marmo Lucon; Daisa Silva Ribeiro David; Willian Nahas; Ioannis M. Antonopoulos; Miguel Srougi
OBJECTIVE There are no data to support the suggestion that samples removed from one segment of the transplanted kidney are representative of the whole graft. The aim of this study was to compare the histological differences between biopsies obtained from different portions of the renal allograft and their impact on treatment recommendations. PATIENTS AND METHODS Two hundred percutaneous biopsies were performed on kidney allografts and samples were collected from the upper and lower poles (100 kidneys). All samples were randomized and blindly reviewed. We obtained the discordance rates between the poles for the grading of acute rejection and for the diagnosis of nephrotoxicity due to immunosuppression. We also checked if the differences found were sufficient to call for different clinical recommendations. These values were compared with the intrapathologist variation rates. RESULTS In 70 kidneys adequate sampling was obtained from both poles. The diagnosis of acute rejection were made in 17. The discordance rate between the upper and lower poles was 82.3% (kappa = 0.34), higher than the intrapathologist variation (P = .002). Nephrotoxicity was found in 14 kidneys. The discordance rate between the upper and lower poles was 28.6% (kappa = 0.88), with no difference compared with the intrapathologist variation. In 14 of the 70 kidneys (25.7%), discordances between poles had impact on clinical recommendations, most of these cases due to different gradings of acute rejection (78%). This number was higher than the intrapathologist variation (P = .04). CONCLUSIONS The histopathological changes in the kidney allograft are not always homogeneous. This heterogeneity may affect the therapeutic recommendations.