996 resultados para liver membrane
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Introduction. The use of arterial grafts (AG) in pediatric orthotopic liver transplantation (OLT) is an alternative in cases of poor hepatic arterial inflow, small or anomalous recipient hepatic arteries, and retransplantations (re-OLT) due to hepatic artery thrombosis (HAT). AG have been crucial to the success of the procedure among younger children. Herein we have reported our experience with AG. Methods. We retrospectively reviewed data from June 1989 to June 2010 among OLT in which we used AG, analyzing indications, short-term complications, and long-term outcomes. Results. Among 437 pediatric OLT, 58 children required an AG. A common iliac artery interposition graft was used in 57 cases and a donor carotid artery in 1 case. In 38 children the graft was used primarily, including 94% (36/38) in which it was due to poor hepatic arterial inflow. Ductopenia syndromes (n = 14), biliary atresia (BA; n = 11), and fulminant hepatitis (n = 8) were the main preoperative diagnoses among these children. Their mean weight was 18.4 kg and mean age was 68 months. At the mean follow-up of 27 months, multiple-organ failure and primary graft nonfunction (PNF) were the short-term causes of death in 9 children (26.5%). Among the remaining 29 patients, 2 (6,8%) developed early graft thrombosis requiring re-OLT; 5 (17%) developed biliary complications, and 1 (3.4%) had asymptomatic arterial stenosis. In 20 children, a graft was used during retransplantation. The main indication was HAT (75%). BA (n = 15), ductopenia syndromes (n = 2), and primary sclerosing cholangitis (n = 2) were the main diagnoses. Their mean weight was 16.7 kg and age was 65 months. At a mean follow-up of 53 months, 7 children died due to multiple-organ failure or PNF. Among the remaining 13 patients, 3 developed biliary complications and 1 had arterial stenosis. No thrombosis was observed. Conclusion. The data suggested that use of an AG is useful alternative in pediatric OLT. The technique is safe with a low risk of thrombosis.
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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.
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Background/Purpose. Posttransplantation portal vein thrombosis (PVT) can have severe health consequences, and portal hypertension and other consequences of the long-term privation of portal inflow to the graft may be hazardous, especially in young children. The Rex shunt has been used successfully to treat PVT patients since 1998. In 2007, we started to perform this surgery in patients with idiopathic PVT and late posttransplantation PVT. Herein we have reported our experience with this technique in acute posttransplantation PVT. Methods. Three patients of ages 12, 15, and 18 months underwent cadaveric (n = 1) or living donor (n = 2) orthotopic liver transplantation (OLT). All patients had biliary atresia with portal vein hypoplasia; they developed acute PVT on the first postoperative day. They underwent a mesenteric-portal surgical shunt (Rex shunt) using a left internal jugular vein autograft (n = 2) or cadaveric iliac vein graft (n = 1) on the first postoperative day. Results. The 8-month follow-up has confirmed shunt patency by postoperative Doppler ultrasound. There have been no biliary complications to date. Conclusions. The mesenteric-portal shunt (Rex shunt) using an autograft of the left internal jugular or a cadaveric vein graft should be considered for children with acute PVT after OLT. These children usually have small portal veins; reanastomosis is often unsuccessful. In addition, this technique has the advantage to avoid manipulation of the hepatic hilum and biliary anastomosis. Although this study was based on a limited experience, we concluded that this technique is feasible, with great benefits to and low risks for these patients.
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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-naive 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.
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Background: Liver resection is considered the best treatment for metastatic colorectal cancer. Several prognostic factors have been investigated, and many studies have shown that hepatic hilum lymph nodes involvement has a negative impact on prognosis. The present study evaluated the frequency of microscopic involvement of hilar lymph nodes, through systematic lymphadenectomy and analysis of micrometastases in patients undergoing hepatectomy due to colorectal metastasis. Methods: A total of 28 patients underwent hepatic resection with hilar lymphadenectomy. Lymph nodes considered negative by conventional hematoxylin and eosin (H&E) staining were analyzed by serial sectioning with 100-mu m intervals and immunohistochemistry (IHC) with antihuman pancytokeratin antibody AE1/AE3. Results: In average, 6.18 lymph nodes were dissected per patient. No morbidity or mortality was associated to lymphadenectomy. In two patients, conventional H&E analysis showed presence of microscopic lymph node metastasis. H&E analysis allowed the identification of three other patients with lymph node micrometastases. The overall frequency of microscopic metastases, including micrometastasis, was 18%. Conclusions: Systematic lymphadenectomy allowed the detection of microscopic lymph node metastases, resulting in more accurate staging of extrahepatic disease. The inclusion of IHC increased the detection of lymph node micrometastasis. J. Surg. Oncol. 2009;100:534-537. (C) 2009 Wiley-Liss, Inc.
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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. Published by Elsevier Inc.
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Background Recent advances in laparoscopic techniques have resulted in growing indications for laparoscopic hepatectomy. However, this procedure has not been widely developed, and anatomic segmental liver resection is not Currently performed due to difficulty controlling the segmental Glissonian pedicles laparoscopically. This study aimed to report a novel technique for laparoscopic anatomic resection of left liver segments using the intrahepatic Glissonian approach based on small incisions according to anatomic landmarks such as Arantius` and round ligaments. Methods Nine consecutive patients underwent laparoscopic liver resection using the intrahepatic Glissonian technique from April 2007 to June 2008. Five patients underwent laparoscopic bisegmentectomy 2-3, one laparoscopic left hemihepatectomy, two resections of segment 3, and one resection of segment 4. Results One patient required a blood transfusion. The mean operation time was 180 min (range, 120-300 min), and the median hospital stay was 3 days (range, 1-5 days). No patient had postoperative signs of liver failure or bile leakage. No postoperative mortality was observed. Conclusion The main advantage of the intrahepatic Glissonian procedure over other techniques is the possibility of gaining a rapid and precise access to the left Glissonian sheaths facilitating left hemihepatectomy, bisegmentectomy 2-3, and individual resections of segments 2, 3, and 4. The authors believe that the intrahepatic Glissonian technique facilitates laparoscopic liver resection and may increase the development of segment-based laparoscopic liver resection.
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As a consequence of selective pressure exerted by the immune response during hepatitis C virus (HCV) infection, a high rate of nucleotide mutations in the viral genome is observed which leads to the emergence of viral escape mutants. The aim of this study was to evaluate the evolution of the amino acid (aa) sequence of the HCV nonstructural protein 3 (NS3) in viral isolates after liver transplantation. Six patients with HCV-induced liver disease undergoing liver transplantation (LT) were followed up for sequence analysis. Hepatitis C recurrence was observed in all patients after LT. The rate of synonymous (dS) nucleotide substitutions was much higher than that of nonsynonymous (dN) ones in the NS3 encoding region. The high values of the dS/dN ratios suggest no sustained adaptive evolution selection pressure and, therefore, absence of specific NS3 viral populations. Clinical genotype assignments were supported by phylogenetic analysis. Serial samples from each patient showed lower mean nucleotide genetic distance when compared with samples of the same HCV genotype and subtype. The NS3 samples studied had an N-terminal aa sequence with several differences as compared with reference ones, mainly in genotype 1b-infected patients. After LT, as compared with the sequences before, a few reverted aa substitutions and several established aa substitutions were observed at the N-terminal of NS3. Sites described to be involved in important functions of NS3, notably those of the catalytic triad and zinc binding, remained unaltered in terms of aa sequence. Rare or frequent aa substitutions occurred indiscriminately in different positions. Several cytotoxic T lymphocyte epitopes described for HCV were present in our 1b samples. Nevertheless, the deduced secondary structure of the NS3 protease showed a few alterations in samples from genotype 3a patients, but none were seen in 1b cases. Our data, obtained from patients under important selective pressure during LT, show that the NS3 protease remains well conserved, mainly in HCV 3a patients. It reinforces its potential use as an antigenic candidate for further studies aiming at the development of a protective immune response.
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A flow cytometry-adapted fluorescent antibody to membrane antigen (FAMA) assay to detect IgG antibodies against varicella-zoster virus (VZV) was developed and tested in 62 serum samples, showing 90.32% accuracy obtained from a receiver operating characteristic (ROC) curve with a 0.9125 (95% confidence interval [CI], 0.829 to 1.00) area below the curve compared to the result with standard FAMA.
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The majority of severe hypersensitivity reactions in hemodialysis patients have occurred due to sensitization to ethylene oxide or to nonbiocompatible membrane dialyzers. The use of polysulfone dialyzers rarely causes hypersensitivity reactions. In the present study, we describe a case of severe life-threatening reactions induced by polysulfone dialyzers (from different manufacturers subjected to a variety of sterilization methods), which occurred after 9 sessions of hemodialysis with the same prescription, exemplifying the complexity of such reactions.
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Background and Aims. Liver transplantation (OLT) in children has seen significant improvements in recent years. Long-term immunosuppressive strategies have focused on avoiding the risks of long-term immunosuppression, particularly nephrotoxicity, de novo malignancy and late infections. Since its introduction in renal transplantation in 1999, sirolimus (SRL) has been used by an increasing number of liver transplant centers. The aim of this study was to review the experience using SRL in pediatric liver transplant recipients at a single center. Methods. Between 1989 and 2006, 318 children underwent OLT including 13 who were converted to SRL therapy because of tacrolimus-related side effects. The indications were posttransplant lymphoproliferative disease (PTLD; n = 11), nephrotoxicity (n = 1), and de novo autoimmune hepatitis (n = 1). One patient with PTLD previously concurrently displayed chronic rejection. SRL dosages ranged between 0.4 and 5 mg/d. The median duration of follow-up was 18 months. Results. PTLD recurred in 1 patient. There were no episodes of acute rejection. One child developed hyperlipidemia that resolved with diet and medication. Conclusions. Conversion from tacrolimus to SRL in selected pediatric liver transplant recipients is safe. Children with PTLD may benefit from immunosuppression with SRL after liver transplantation.
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Background and Purpose. Late portal vein thrombosis (PVT) can be extremely well tolerated, although portal hypertension and other consequences of the long-term deprivation of portal inflow to the graft may be hazardous, especially in young children. Recently, the ""Rex shunt"" has been used successfully to treat these patients. We now report the initial experience with this novel technique. Methods. A 3-year-old girl with PVT at 7 months after whole organ cadaveric liver transplant displayed portal hypertension with an episode of gastrointestinal bleeding, requiring a mesenteric-portal surgical shunt (""Rex shunt"") using a left internal jugular vein autograft. Results. Upon current follow-up of 6 months, postoperative Doppler ultrasound confirmed shunt patency. Endoscopic status was significantly improved after surgery with resolution of portal hypertension. There was no recurrence of bleeding. Conclusions. The mesenteric-portal shunt (""Rex shunt""), using a left internal jugular vein autograft, should be considered for children with late PVT after liver transplantation. Although this is an initial experience, we may conclude that this technique is feasible, with great potential benefits and low risks for these patients.
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Background: Enucleation of small lesions located near the hepatic surface can be achieved with low morbidity and mortality. This article describes a simple laparoscopic technique for enucleation of liver tumors. Methods: After inspection and intraoperative ultrasonography, Glisson`s capsule is marked with eletrocautery 2 cm away from the tumor margin. Ultrasonography is used to ascertain surgical margin right before liver transection. Hemihepatic ischemia is applied and marked area is anchored by stitches. The suture is held together by metallic clips and upward traction is performed, facilitating the transection of the parenchyma and correct identification of vascular and biliary structures. Results: This technique has been successfully employed in six consecutive patients. There were four men and two women, mean age 50.3 years. Four patients underwent liver resection for malignant disease and two for benign liver neoplasm. Pathologic surgical margins were free in all cases and mean hospital stay was 2 days. No postoperative mortality was observed. Conclusion: This technique may facilitate laparoscopic nonanatomical liver resection and reduce risk of positive surgical margins. It is also useful in combination with anatomical laparoscopic liver resections such as right or left hemihepatectomies in patients with bilateral liver tumors as occurred in one of our patients.
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Experience with laparoscopic liver resections has increased in recent years, and so have the number of patients operated on by minimally invasive techniques. Specimen extraction is an important step of laparoscopic liver resection. The size of the specimen, is Usually a limitation for the use Of laparoscopy. The aim of this paper is to describe a new technique combining Pfannenstiel suprapubic incision and obstetric forceps to remove a large specimen from laparoscopic liver resections. The present technique allows an expeditious extraction of intact specimens, even huge ones, through a standard suprapubic Pfannenstiel incision. This technique has additional functional and cosmetic advantages over other techniques of specimen retrieval. We believe that the described technique is feasible, can be easily and rapidly performed, and facilitates laparoscopic liver resection by reducing the technical difficulties for specimen removal and may also be used in other abdominal laparoscopic interventions that deal with large surgical specimens.