Helena T. Miyatani
University of São Paulo
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Pediatric Transplantation | 2005
Uenis Tannuri; Evandro Sobroza de Mello; Francisco Cesar Carnevale; Maria M. Santos; Nelson Elias Mendes Gibelli; Ali A. Ayoub; João Gilberto Maksoud-Filho; Manoel Carlos Prieto Velhote; Marcos Silva; Maria L. Pinho; Helena T. Miyatani; João Gilberto Maksoud
Abstract: In pediatric patients submitted to living related liver transplantation, hepatic venous reconstruction is critical because of the diameter of the hepatic veins and the potential risk of twisting of the graft over the line of the anastomosis. The aim of the present study is to present our experience in hepatic venous reconstruction performed in pediatric living related donor liver transplantation. Fifty‐four consecutive transplants were performed and two methods were utilized for the reconstruction of the hepatic vein: direct anastomosis of the orifice of the donor left or left and middle hepatic veins and the common orifice of the recipient left and middle hepatic veins (group 1–26 cases), and wide triangular anastomosis after creating a wide triangular orifice in the recipient inferior vena cava at the confluence of all the hepatic veins with an additional longitudinal incision in the inferior angle of the orifice (group 2–28 cases). In group 1, eight patients were excluded because of graft problems in the early postoperative period and five among the remaining 18 patients (27.7%) presented stricture at the site of the hepatic vein anastomosis. All these patients had to be submitted to two or three sessions of balloon dilatations of the anastomoses and in four of them a metal stent had to be placed. The liver histopathological changes were completely reversed by the placement of the stent. Among the 28 patients of the group 2, none of them presented hepatic vein stenosis (p = 0.01). The results of the present series lead to the conclusion that hepatic venous reconstruction in pediatric living donor liver transplantation must be preferentially performed by using a wide triangulation on the recipient inferior vena cava, including the orifices of the three hepatic veins. In cases of stenosis, the endovascular dilatation is the treatment of choice followed by stent placement in cases of recurrence.
Transplantation Proceedings | 2011
Ana Cristina Aoun Tannuri; Nelson Elias Mendes Gibelli; Luiz Roberto Schlaich Ricardi; Maria Mercês Santos; João Gilberto Maksoud-Filho; M.L. Pinho-Apezzato; M. M. Silva; Manoel Carlos Prieto Velhote; Ali A. Ayoub; Wagner de Castro Andrade; Antonio José Gonçalves Leal; Helena T. Miyatani; Uenis Tannuri
OBJECTIVE The objective of this study was to report our experience with pediatric orthotopic liver transplantation (OLT) with living related donors. METHODS We performed a retrospective chart analysis of 121 living related donor liver transplantations (LRDLT) from June 1998 to June 2010. RESULTS Indications were biliary atresia (BA; n = 81), primary sclerosing cholangitis (n = 5), α-1 antitrypsin deficiency (n = 4); cholestasis (n = 9), fulminant hepatic failure (n = 8), autoimmune hepatitis (n = 2), Alagille syndrome (n = 4), hepatoblastoma (n = 3), tyrosinemia (n = 2), and congenital hepatic fibrosis (n = 3). The age of the recipients ranged from 7-174 months (median, 22) and the weights ranged from 6-58 kg (median, 10). Forty-nine children (40.5%) weighed ≤10 kg. The grafts included the left lateral segment (n = 108), the left lobe (n = 12), and the right lobe (n = 1). The donors included 71 mothers, 45 fathers, 2 uncles, 1 grandmother, 1 grandfather, and 1 sister with a median age of 29 years (range, 16-53 ys) and a median weight of 68 kg (range, 47-106). Sixteen patients (12.9%) required retransplantation, most commonly due to hepatic artery thrombosis (HAT; n = 13; 10.7%). The other complications were biliary stenosis (n = 25; 20.6%), portal vein thrombosis (PVT; n = 11; 9.1%), portal vein stenosis (n = 5; 4.1%), hepatic vein stenosis (n = 6; 4.9%), and lymphoproliferative disorders (n = 8; 6.6%). The ultimate survival rate of recipients was 90.3% after 1 year and 75.8% after 3 years. Causes of early death within 1 month were HAT (n = 6), PVT (n = 2), severe graft dysfunction (n = 1), sepsis (n = 1), and intraoperative death in children with acute liver failure (n = 2). Causes of late deaths included lymphoproliferative disease (n = 3), chronic rejection (n = 2), biliary complications (n = 3), and recurrent disease (n = 3; hepatoblastoma and primary sclerosing cholangitis). CONCLUSIONS Despite the heightened possibility of complications (mainly vascular), LRDLT represented a good alternative to transplantation from cadaveric donors in pediatric populations. It was associated with a high survival ratio.
Transplantation Proceedings | 2010
M.L. Pinho-Apezzato; Uenis Tannuri; Ana Cristina Aoun Tannuri; Evandro Sobroza de Mello; F. Lima; Nelson Elias Mendes Gibelli; Maria Mercês Santos; Ali A. Ayoub; João Gilberto Maksoud-Filho; Manoel Carlos Prieto Velhote; M. M. Silva; Wagner de Castro Andrade; Helena T. Miyatani
Posttransplantation lymphoproliferative disorder (PTLD) is a serious complication following solid organ transplantation that has been linked to Epstein-Barr virus (EBV) infection. The aim of this article was to describe a single-center experience with the multiplicity of clinical presentations of PTLD. Among 350 liver transplantations performed in 303 children, 13 survivor children displayed a histological diagnosis of PTLD (13/242 survivors; 5.4%). The age at diagnosis ranged from 12 to 258 months (median, 47), and the time from transplantation ranged from 1 to 84 months (median, 13). Ten of these children (76.9%) were EBV-naïve prior to transplantation. Fever was present in all cases. The clinical signs at presentation were anemia (92.3%), diarrhea and vomiting (69.2%), recurrent upper airway infections (38.4%), Waldeyer ring lymphoid tissue hypertrophy (23.0%), abdominal mass lesions (30.7%), massive cervical and mediastinal adenopathy (15.3%), or gastrointestinal and respiratory symptoms (30.7%). One child developed fulminant hepatic allograft failure secondary to graft involvement by PTLD. Polymorphic PTLD was diagnosed in 6 patients; 7 had the diagnosis of lymphoma. Treatment consisted of stopping immunosuppression as well as starting intravenous gancyclovir and anti-CD20 monoclonal antibody therapy. The mortality rate was 53.8%. The clinical presentation of PTLD varied from fever of unknown origin to fulminant hepatic failure. The other symptoms that may be linked to the diagnosis of PTLD are pancytopenia, tonsil and adenoid hypertrophy, cervical or mediastinal lymph node enlargement, as well as abdominal masses. Despite numerous advances, the optimal treatment approach for PTLD is not completely known and the mortality rate is still high.
Pediatric Transplantation | 2010
Maria M. Santos; Ana Cristina Aoun Tannuri; Nelson Elias Mendes Gibelli; Ali A. Ayoub; João Gilberto Maksoud-Filho; Wagner de Castro Andrade; Manoel Carlos Prieto Velhote; Marcos Silva; Maria L. Pinho; Helena T. Miyatani; Liza Susuki; Uenis Tannuri
Santos MM, Tannuri ACA, Gibelli NE, Ayoub AA, Maksoud‐Filho JG, Andrade WC, Velhote MCP, Silva MM, Pinho ML, Miyatani HT, Suzuki L, Tannuri U. Posterior reversible encephalopathy syndrome after liver transplantation in children: A rare complication related to calcineurin inhibitor effects. Pediatr Transplantation 2011: 15:157–160.
Journal of Pediatric Surgery | 2011
Uenis Tannuri; Maria M. Santos; Ana Cristina Aoun Tannuri; Nelson Elias Mendes Gibelli; Airton Mota Moreira; Francisco Cesar Carnevale; Ali A. Ayoub; João Gilberto Maksoud-Filho; Wagner de Castro Andrade; Manoel Carlos Prieto Velhote; Marcos Silva; M.L. Pinho-Apezzato; Helena T. Miyatani; Raimundo Renato Nunes Guimarães
BACKGROUND/PURPOSE The introduction of the piggyback technique for reconstruction of the liver outflow in reduced-size liver transplants for pediatric patients has increased the incidence of hepatic venous outflow block (HVOB). Here, we proposed a new technique for hepatic venous reconstruction in pediatric living-donor liver transplantation. METHODS Three techniques were used: direct anastomosis of the orifice of the donor hepatic veins and the orifice of the recipient hepatic veins (group 1); triangular anastomosis after creating a wide triangular orifice in the recipient inferior vena cava at the confluence of all the hepatic veins (group 2); and a new technique, which is a wide longitudinal anastomosis performed at the anterior wall of the inferior vena cava (group 3). RESULTS In groups 1 and 2, the incidences of HVOB were 27.7% and 5.7%, respectively. In group 3, no patient presented HVOB (P = .001). No difference was noted between groups 2 and 3. CONCLUSIONS Hepatic venous reconstruction in pediatric living-donor liver transplantation must be preferentially performed by using a wide longitudinal incision at the anterior wall of the recipient inferior vena cava. As an alternative technique, triangulation of the recipient inferior vena cava, including the orifices of the 3 hepatic veins, may be used.
Transplantation Proceedings | 2011
Ana Cristina Aoun Tannuri; Nelson Elias Mendes Gibelli; Luiz Roberto Schlaich Ricardi; M. M. Silva; Maria Mercês Santos; M.L. Pinho-Apezzato; João Gilberto Maksoud-Filho; Manoel Carlos Prieto Velhote; Ali A. Ayoub; Wagner de Castro Andrade; A.N. Backes; Helena T. Miyatani; Uenis Tannuri
INTRODUCTION Biliary atresia (BA) is the leading indication for orthotopic liver transplantation (OLT) among children. However, there are technical difficulties, including the limited dimensions of anatomical structures, hypoplasia and/or thrombosis of the portal vein and previous portoenterostomy procedures. OBJECTIVE The objective of this study was to present our experience of 239 children with BA who underwent OLT between September 1989 and June 2010 compared with OLT performed for other causes. METHODS We performed a retrospective analysis of patient charts and analysis of complications and survival. RESULTS BA was the most common indication for OLT (207/409; 50.6%). The median age of subjects was 26 months (range, 7-192). Their median weight was 11 kg (range, 5-63) with 110 children (53.1%) weighing ≤10 kg. We performed 126 transplantations from cadaveric donors (60.8%) and 81 from living-related donors (LRD) (39.2%). Retransplantation was required for 31 recipients (14.9%), primarily due to hepatic artery thrombosis (HAT; 64.5%). Other complications included the following: portal vein thrombosis (PVT; 13.0%), biliary stenosis and/or fistula (22.2%), bowel perforation (7.0%), and posttransplantation lymphoproliferative disorder (PTLD; 5.3%). Among the cases of OLT for other causes, the median age of recipients was 81 months (range, 11-17 years), which was higher than that for children with BA. Retransplantation was required in 3.5% of these patients (P < .05), mostly due to HAT. The incidences of PVT, bowel perforation, and PTLD were significantly lower (P < .05). There was no significant difference between biliary complications in the 2 groups. The overall survival rates at 1 versus 5 years were 79.7% versus 68.1% for BA, and 81.2% versus 75.7% for other causes, respectively. CONCLUSIONS Children who undergo OLT for BA are younger than those engrafted for other causes, displaying a higher risk of complications and retransplantations.
Pediatric Transplantation | 2015
Uenis Tannuri; Ana Cristina Aoun Tannuri; Maria M. Santos; Helena T. Miyatani
HVOO represents a serious critical complication of pediatric living‐donor liver transplantation because open surgical repair is virtually impossible. Currently, despite several technical innovations and the introduction of triangulated anastomosis for hepatic vein reconstruction, the reported incidence of HVOO is still considerable. The aim of this study was to propose a new technique for hepatic venous reconstruction that avoids the original orifice of the recipient hepatic veins. Instead, anastomosis is performed in a newly created wide longitudinal orifice in the anterior wall of the recipient inferior vena cava. A total of 210 living related‐donor liver transplantations were performed using two methods for reconstruction of the hepatic vein. Group 1 included 69 patients subjected to direct anastomosis of the orifice of the graft hepatic vein and a wide orifice created in the recipient inferior vena cava by the confluence of the orifices of the right, left, and middle hepatic veins. Group 2 included 141 patients in whom the original orifices of the recipient hepatic veins were closed, the inferior vena cava was widely opened, and a long longitudinal anastomosis was performed using two lines of continuous sutures. Diagnosis of HVOO was suspected based on clinical findings and ultrasound studies and then confirmed by liver biopsy and interventional radiology examinations. Among the 69 recipients in group 1, 16 patients died due to graft problems during the postoperative period and eight of the survivors (15.1%) presented with HVOO. In group 2 (141 patients), 21 patients died, and there were no cases of HVOO. A comparison of the incidence of HVOO between groups revealed a significant difference (p = 0.01). Hepatic venous reconstruction during pediatric living‐donor liver transplantation should be performed using a wide longitudinal incision in the anterior wall of the recipient inferior vena cava because this technique eliminated anastomosis complications.
Journal of Pediatric Surgery | 2014
Ana Cristina Aoun Tannuri; Roberta Figueiredo Monteiro; Maria Mercês Santos; Helena T. Miyatani; Uenis Tannuri
BACKGROUND/AIM Hepatic artery anastomosis (HAA) is the most important aspect of living donor liver transplantation (LDLT), and it is currently performed by a specialized microsurgeon using micro surgical techniques, with interrupted sutures and the aid of an operative microscope. To simplify the procedure, we studied a new, simpler technique performed by pediatric transplant surgeons with continuous sutures and the same 3.5× magnification loupe used during other transplant procedures. The aim of this study was to compare these two hepatic artery reconstruction techniques in two pediatric LDLT series. METHODS This study was initiated in January 2010 and finished in June 2013. In the first period, the arterial reconstruction was performed with an operating microscope and the classical technique of 9-0 separate sutures. In the second period, the arterial reconstruction was performed using a simpler technique, with surgical loupe and continuous 8-0 Prolene sutures. The incidences and outcomes of complications within the two periods were analyzed and compared. RESULTS A total of 82 LDLTs were performed, 38 in the first period and 44 in the second period. There were no differences between the periods, except for the arterial ischemia time, which was lower in the second period. CONCLUSION Hepatic artery anastomosis can be safely performed with low complication rates by a pediatric transplant surgeon using continuous sutures with a 3.5× magnifying loupe. This technique is simpler, less time consuming and simplifies the complex pediatric LDLT procedure.
Liver Transplantation | 2016
Ana Cristina Aoun Tannuri; Gilda Porta; Irene Miura; Maria Mercês Santos; Daniel Moreira; Nathássia Mancebo Ávila de Rezende; Helena T. Miyatani; Uenis Tannuri
Acute liver failure (ALF) in children is a life‐threatening condition that often leads to urgent liver transplantation (LT). The aim of the present investigation was to describe the experience in Brazil in treating pediatric ALF, with an emphasis on the role of living donor liver transplantation (LDLT) in treating this condition. All children with ALF who fulfilled the criteria for an urgent LT were admitted to the intensive care unit. Patients were divided into 2 groups based on the moment of admission: before and after June 2007, when the LDLT program for ALF was started. Statistical analyses were performed to identify prognostic factors of patients with ALF. For the study, 115 children with ALF were admitted. All patients had some degree of encephalopathy. Among the patients, 26% of them required intracranial pressure monitoring (IPM), 12.8% of the patients required hemodialysis, and 79 patients underwent transplantation (50 deceased donors and 29 living donors) corresponding to 12.4% of all pediatric LTs. Only 9 children recovered without LT. The need for IPM and nonperformance of LT were related to a higher mortality. The mortality rate of patients who underwent LT was significantly lower than that of children with ALF who did not undergo a LT (48.1% versus 75%; P = 0.02). The incidences of primary nonfunction and mortality were statistically higher among deceased donor liver transplantations than LDLTs. Finally, it was verified that the overall survival rate of transplanted patients was increased after the introduction of LDLT (P = 0.02). In conclusion, ALF in children continues to be a severe and devastating condition, and a LT should be performed promptly. The introduction of LDLT could increase the survival rate of patients in Brazil. Liver Transplantation 22 1006–1013 2016 AASLD
Journal of Pediatric Surgery | 2014
Wagner de Castro Andrade; Manoel Carlos Prieto Velhote; Ali Ahman Ayoub; M. M. Silva; Nelson Elias Mendes Gibelli; Ana Cristina Aoun Tannuri; Maria Mercês Santos; M.L. Pinho-Apezzato; Fabio de Barros; Daniel Moreira; Helena T. Miyatani; Raimundo Renato Pereira; Uenis Tannuri
BACKGROUND/PURPOSE Living donor liver transplantation has become a cornerstone for the treatment of children with end-stage hepatic dysfunction, especially within populations or countries with low rates of organ utilization from deceased donors. The objective is to report our experience with 185 living donors operated on by a team pediatric surgeons in a tertiary center for pediatric liver transplantation. METHODS Retrospective analysis of medical records of donors of hepatic grafts for transplant undergoing surgery between June 1998 and March 2013. RESULTS Over the last 14 years, 185 liver transplants were performed in pediatric recipients of grafts from living donors. Among the donors, 166 left lateral segments (89.7%), 18 left lobes without the caudate lobe (9.7%) and 1 right lobe (0.5%) were harvested. The donor age ranged from 16 to 53 years, and the weight ranged from 47 to 106 kg. In 10 donors, an additional graft of the donor inferior mesenteric vein was harvested to substitute for a hypoplastic recipient portal vein. The transfusion of blood products was required in 15 donors (8.1%). The mean hospital stay was 5 days. No deaths occurred, but complications were identified in 23 patients (12.4%): 9 patients experienced abdominal pain and severe gastrointestinal symptoms and 3 patients required reoperations. Eight donors presented with minor bile leaks that were treated conservatively, and 3 patients developed extra-peritoneal infections (1 wound collection, 1 phlebitis and 1 pneumonia). Eight grafts (4.3%) showed primary dysfunction resulting in recipient death (3 cases of fulminant hepatitis, 1 patient with metabolic disease, 1 patient with Alagille syndrome and 3 cases of biliary atresia in infants under 1 year old). There was no relation between donor complications and primary graft dysfunction (P=0.6). CONCLUSIONS Living donor transplantation is safe for the donor and presents a low morbidity. The donor surgery may be performed by a team of trained pediatric surgeons.