Werviston DeFaria
University of Miami
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Featured researches published by Werviston DeFaria.
Annals of Surgery | 2005
Andreas G. Tzakis; Tomoaki Kato; David Levi; Werviston DeFaria; Gennaro Selvaggi; Debbie Weppler; Seigo Nishida; Jang Moon; Juan Madariaga; Andre Ibrahim David; Jeffrey J. Gaynor; John F. Thompson; E. Hernandez; Enrique J. Martinez; G. Patricia Cantwell; Jeffrey S. Augenstein; Anthony Gyamfi; Ernesto A. Pretto; Lorraine A. Dowdy; Panagiotis Tryphonopoulos; Phillip Ruiz; Goran B. Klintmalm; Thomas E. Starzl; Kareem Abu-Elmagd; David F. Grant; John S. Najarian; Donald D. Trunkey
Objective:The objective of this study was to summarize the evolution of multivisceral transplantation over a decade of experience and evaluate its current status. Summary Background Data:Multivisceral transplantation can be valuable for the treatment of patients with massive abdominal catastrophes. Its major limitations have been technical and rejection of the intestinal graft. Methods:This study consisted of an outcome analysis of 98 consecutive patients who received multivisceral transplantation at our institution. This represents the largest single center experience to date. Results:The most common diseases in our population before transplant were intestinal gastroschisis and intestinal dysmotility syndromes in children, and mesenteric thrombosis and trauma in adults. Kaplan Meier estimated patient and graft survivals for all cases were 65% and 63% at 1 year, 49% and 47% at 3 years, and 49% and 47% at 5 years. Factors that adversely influenced patient survival included transplant before 1998 (P = 0.01), being hospitalized at the time of transplant (P = 0.05), and being a child who received Campath-1H induction (P = 0.03). Among 37 patients who had none of these 3 factors (15 adults and 22 children), estimated 1- and 3-year survivals were 89% and 71%, respectively. Patients transplanted since 2001 had significantly less moderate and severe rejections (31.6% vs 67.6%, P = 0.0005) with almost half of these patients never developing rejection. Conclusions:Multivisceral transplantation is now an effective treatment of patients with complex abdominal pathology. The incidences of serious acute rejection and patient survival have improved in the most recent experience. Our results show that the multivisceral graft seems to facilitate engraftment of transplanted organs and raises the possibility that there is a degree of immunologic protection afforded by this procedure.
Annals of Surgery | 2006
Tomoaki Kato; Andreas G. Tzakis; Gennaro Selvaggi; Jeffrey J. Gaynor; Andre Ibrahim David; Alessandro Bussotti; Jang I. Moon; Takehisa Ueno; Werviston DeFaria; S. Santiago; David Levi; Seigo Nishida; Gwen McLaughlin; E. Hernandez; John F. Thompson; Patricia Cantwell; Norman Holliday; Alan S. Livingstone; Phillip Ruiz
Objective:To describe a single-center experience of pediatric intestinal transplantation (Itx) and to provide an overview of the children who underwent this procedure along with their outcomes. Summary Background Data:Pediatric Itx presents multiple challenges because of the very young ages at which patients require transplantation and their higher susceptibility to infectious complications. Methods:We have performed 141 Itx in 123 children with a median age of 1.37 years. Primary grafts included isolated intestine (n = 28), liver and intestine (n = 27), multivisceral (n = 61), and multivisceral without the liver (n = 7). Two protocol modifications were introduced in 1998: daclizumab induction and frequent rejection surveillance. In 2001, indications for multivisceral transplantation were expanded, and induction with Campath-1H was introduced. Results:Actuarial patient survival at 1 and 3 years for group 1 (January 1994 to December 1997, n = 25), group 2 (January 1998 to March 2001, n = 29), group 3a (April 2001 to present, daclizumab, n = 51), and group 3b (April 2001 to present, Campath-1H, n = 18) was 44%/32%, 52%/38%, 83%/60%, and 44%/44%, respectively (P = 0.0003 in favor of group 3a). Severe rejection implied a dismal prognosis (65% mortality at 6 months). Observed incidence of severe rejection in groups 1, 2, 3a, and 3b was 32%, 24%, 14%, and 11%, respectively. In multivariable analysis, use of a multivisceral (with or without liver) transplant (P = 0.002), induction with daclizumab (P = 0.005), patient at home prior to transplant (P = 0.007), and age at transplant ≥1 year (P = 0.02) favorably influenced patient survival. Multivisceral transplant was protective with respect to the mortality rate due to rejection, while an older age at transplant was associated with both a lower incidence rate of developing respiratory infection and lower risk of mortality following the respiratory infection. Survivors are off parenteral nutrition and have demonstrated significant growth catch-up. Conclusions:Itx in children still is a high-risk procedure but has now become a viable option for children who otherwise have no hope for survival. Control of respiratory infection is of particular importance in the younger children.
Transplantation | 2009
Donna L. Avison; Werviston DeFaria; Panagiotis Tryphonopoulos; Akin Tekin; George R. Attia; Hidenori Takahashi; Yide Jin; Emmanouil Palaios; Nikolaos Pararas; Manuel Carreno; S. Santiago; Fuller W. Bazer; Phillip Ruiz; Andreas G. Tzakis
Background. The aim of our study was to examine the feasibility of allogeneic uterine transplantation in a large animal model. Methods. We performed heterotopic uterine transplants in genetically defined mini-pigs. Immunosuppression was tacrolimus administered intravenously for the first 12 days posttransplantation followed by oral cyclosporine maintenance immunosuppression. The graft was transplanted heterotopically in the lower abdominal cavity of the recipient. The vaginal vault was exteriorized as a stoma in the lower right abdominal wall. The uterine grafts were followed with endoscopies and biopsies. Results. Ten transplants were performed. Follow-up was until July 2008. At the end of the follow-up period, 5 animals were alive and healthy, 0.5 to 12 months posttransplantation. There were 5 deaths due to pneumonia (n=1), intussusception of the graft (n=1), cardiorespiratory arrest during anesthesia (n=1), and complications of the stoma (n=2). Acute rejections of the graft presented during the 2nd and 3rd month posttransplantation were treated successfully with increase of the maintenance immunosuppression and steroids. Other complications included prolapse and infections of the graft stoma. Pathological changes seen in the endometrial biopsies included acute rejection and acute endometritis. Conclusion. These findings demonstrate that successful uterus transplantation in a large animal model (miniature swine) is feasible using this heterotopic model, and it can be useful for the study of these transplants.
Transplantation | 1999
M. Masetti; Maria M. Rodriguez; John F. Thompson; Antonio Daniele Pinna; Tomoaki Kato; Rita L. Romaguera; Jose Nery; Werviston DeFaria; M.F. Khan; Roberto Verzaro; Phillip Ruiz; Andreas G. Tzakis
BACKGROUND Megacystis microcolon intestinal hypoperistalsis syndrome (MMIHS) is a rare autosomal recessive disorder causing a functional neonatal bowel obstruction. Its etiopathogenesis is not fully understood. The prognosis is poor in the majority of cases; most patients die before the age of 6 months. In this report, we describe our experience with three patients with MMIHS in whom multivisceral transplantation was performed. METHODS Three patients with MMIHS underwent multivisceral transplantation. All patients were females with a history of long-term total parenteral nutrition (TPN) with TPN-related cholestatic liver disease. RESULTS Patient 1 died 17 months after transplantation because of aspiration after revision of her feeding gastrostomy. At the time of death, the graft was functioning and the patient was completely off TPN. Patient 2 is alive 17 months after transplant. She is a fully functional, active 2-year-old and has also recently begun oral feeding after intensive rehabilitation. Patient 3 died on day 44 of multisystem failure. CONCLUSIONS This is the first report in the literature of multivisceral transplantation for MMIHS. Although one of the three patients died 44 days after surgery from multiorgan system failure, the other two patients had long-term survival after transplant and both grew well on enteral feeding alone. One patient died 17 months from a non-transplant-related complication, while the other is living at home off of TPN, with almost complete dietary rehabilitation 17 months after transplant. Our case reports suggest that multivisceral transplantation is a valuable therapeutic option for patients affected by MMIHS with TPN-induced liver failure.
Pediatric Transplantation | 1999
Antonio Daniele Pinna; D. Weppler; Mariana Berho; M. Masetti; Werviston DeFaria; Tomoaki Kato; John F. Thompson; Camillo Ricordi; Andreas G. Tzakis
Graft‐versus‐host disease (GvHD) is a multi‐organ disease caused by mature donor T cells that are activated by alloantigens expressed by the host antigen‐presenting cells. GvHD has been reported after solid organ transplantation with two principal presentations: humoral and cellular. In the cellular type of GvHD after liver transplantation the symptoms are identical to the GvHD after bone marrow transplant, except that the liver is spared because it lacks host antigens. We have described three cases of intestinal GvHD after pediatric liver transplant with an unusual recurrent late presentation in two patients. Two patients were female, and their age at the time of transplant was 8 and 9 months, respectively, and one was an 8‐month‐old male. They all received reduced liver allografts of identical blood type from three different donors. One patient received two doses of donor bone marrow cell infusion. Two patients received double immunosuppressive therapy constituted by tacrolimus at a dose of 0.05 mg/kg p.o. b.i.d. and steroids 10 mg p.o. daily. One patient received a triple drug immunosuppression with tacrolimus (0.05 mg/kg p.o. b.i.d.), steroids (10 mg p.o. daily) and mycophenolate mofetil (125 mg p.o. b.i.d.). Diagnosis of intestinal GvHD was confirmed histologically on intestinal biopsies performed at the time of presentation of the clinical symptoms or at autopsy.
Transplantation | 2009
Edip Akpinar; Gennaro Selvaggi; David Levi; Jang Moon; Seigo Nishida; E. Island; Werviston DeFaria; Ernesto A. Pretto; Philip Ruiz; Andreas G. Tzakis
Background. Transplantation of more than two livers for recurring graft failure has not been specifically addressed in the literature. Methods. A retrospective analysis was conducted from a total of 2527 overall liver transplants at our institution. Main indications for multiple retransplant included primary nonfunction, chronic rejection, hepatic artery thrombosis, and recurrent disease. Results. We identified 39 patients who received more than two grafts (32 received 3 grafts, 5 received 4 grafts, and 2 received 5 grafts). All patients required interposition arterial grafts from the aorta and hepatojejunostomy for the biliary reconstruction. Seventeen patients are still alive at last follow-up. Perioperative mortality rates after 3rd, 4th, and 5th liver graft were 25%, 14%, and 50%, respectively. Patient and graft survival rates were 72% and 56% at 1 year, respectively. Median length of stay was 27 days and median graft survival was 2.9 years. Conclusions. Selection of patients and a significant use of available resources are some of the important factors that clinicians need to take into account when dealing with multiple retransplantations. With such conditions, however, liver retransplantation of more than two grafts can be a life-saving procedure.
Transplantation | 2001
David Levi; Athela Pefkarou; John A. Fort; Werviston DeFaria; Andreas G. Tzakis
Factor VII deficiency is a serious, potentially lethal disorder of blood coagulation caused by a defect in hepatic factor VII synthesis. We report two children, sisters, both with severe, recurrent hemorrhagic complications from factor VII deficiency, successfully treated with orthotopic liver transplantation. Postoperatively, they remain symptom free with normal coagulation profiles.
Transplantation | 2015
James M. Mathew; Panagiotis Tryphonopoulos; Werviston DeFaria; Phillip Ruiz; Joshua Miller; Terrence A. Barrett; Andreas G. Tzakis; Tomoaki Kato
Background Long-term outcomes of intestinal transplantation are limited by infection and rejection. To understand the underlying immune mechanisms, graft infiltrating and peripheral blood cells were analyzed using multiple ex vivo assays in intestinal transplantation recipients. Methods Infiltrating cells from rejected (graft enterectomy for rejection) and accepted or quiescent (stoma closure in stable transplant recipients) grafts were isolated and phenotypically characterized as to subsets and Toll-like receptor expressions as well as functionally tested for antimicrobial and antidonor immune responses. Multiparameter antidonor immunity was also assessed serially in the peripheral blood. Results The graft infiltrating lymphocytes were mostly of recipient origin in all patients tested. In rejecting grafts, the predominant populations were TcR&agr;&bgr;+CD3+CD8+ T cells, and CD14+ monocytes that coexpressed Toll-like receptor-2, receptor-3, receptor-4, receptor-5, and receptor-9, suggesting innate immune activation. In quiescent allografts the major cell subsets were CD13+CD14− monocytes and CD4+CD25+ T cells with possible regulatory functions. Infiltrating cells from rejected but not quiescent grafts proliferated in response to enteric bacterial and donor antigens as well as killed donor targets. Serial follow-up of peripheral blood indicated donor-specific posttransplant unresponsiveness in micro-cell–mediated lympholysis (m-CML) and mixed lymphocyte reaction (MLR) in recipients with quiescent grafts, but not in recipients with multiple rejection episodes. Enzyme-Linked ImmunoSpot assays yielded parallel results: granzyme-B with micro-cell–mediated lympholysis and interferon-&ggr; with MLR tests. Conclusion These results were consistent with the notion that rejection was associated with innate and acquired antimicrobial and antidonor immune reactivity and that patients with stable grafts were free from these deleterious effects.
Transplantation Proceedings | 2000
Alexandre Bakonyi Neto; Werviston DeFaria; M Berho; Manuel Carreno; Evangelos P. Misiakos; Phillip Ruiz; Luca Inverardi; F Ricart; Kalliopi K. Tsinari; Joshua Miller; C. Ricordi; Andreas G. Tzakis
THE SUCCESSFUL induction of graft-specific tolerance continues to be a challenge in solid organ transplantations. Methods to enhance the natural microchimerism occuring after transplant were evaluated in a rat small bowel transplantation (SBT) model by using donorspecific bone marrow (BM) cells combined with irradiation of the recipient before transplant. The major limitation to this approach is the toxicity of lethal whole-body irradiation, which is used to inactivate host alloimmune responses and permit BM engraftment. In a previous work, we demonstrated that preconditioning regimens based on low doses of irradiation associated with whole or T-cell–depleted BM can successfully decrease the severity of graft rejection; however, an excessive mortality due to graftversus-host disease (GVHD) was observed after transplant. In this study, we evaluated the effect of donor and recipient preconditioning by either low doses of irradiation and/or anti-lymphocyte serum (ALS) on the incidence of GVHD and rejection after SBT.
Biological Research | 2006
P. B. Carroll; Werviston DeFaria; C. Gandia; Mariana Berho; Evangelos P. Misiakos; Andreas G. Tzakis
The creation of successful vascular anastomoses is of primary importance in many surgical fields. Numerous attempts to automate this process have been made. These techniques have slowly gained acceptance, but their use is still limited. This report details feasibility testing of a new prototype stapler that automates the rollover sleeve technique for venous vascular anastomoses. Male and female mongrel dogs (n=7) (25-32 kg) were used. A segment of the right (n=5) or left (n=2) iliac vein was harvested for interposition grafts after the contra lateral side was transected. In each dog, two end-to-end venous anastomoses at the interposition grafts were performed. The standard anastomosis employed continuous mattress sutures. The experimental anastomosis was performed with a new prototype surgical stapler. The stapled anastomosis was proximal and the sutured was distal. In all experiments, it was possible to perform the experimental anastomosis with the stapler. Complications included two small leaks, one due to misfiring of a single pin in one experimental site. These leaks required suture reinforcement. One dog died of hemorrhage due to a slipped suture at the vein harvest site. One vein had thrombus seen at the sutured site although no technical abnormalities at either of the anastomoses could be found. After two weeks, grafts were inspected grossly and histologically. Healing appeared normal. There was a trend for less inflammatory cells infiltrating stapled sites; however, this was not statistically significant. The experiments demonstrate that this device can automate the rollover sleeve technique for venous anastomoses.