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T Yandza

Publications and source records attributed to T Yandza.

At least 19 recordsLinked to original sources
PubMed2002

Hepatic insufficiency and liver transplantation in a patient with COACH syndrome.

An 8-yr-old-patient was diagnosed with COACH syndrome at the moment of her first bleeding episode from esophageal varices. Investigations revealed biliary cirrhosis as the cause of portal hypertension, no visible kidney cyst or impairment of renal function, cerebellar dysplasia with non-disabling ataxia, and minimal mental retardation. By the age of 12 yr she had developed liver insufficiency and, after a challenging discussion, underwent a liver transplantation. She subsequently developed an abdominal aspergillosis, which required several abdominal explorations and splenectomy as well as 6 months of therapy with liposomal amphotericin B, but survived and in long-term follow-up is in good health, with completed puberty, and has finished school.

Abnormalities, Multiple↗
PubMed1999

N-acetylcysteine in pig liver transplantation from non-heart-beating donors.

Lipid peroxidation due to oxygen free radicals (OFR) seems to play a major role in loss of liver graft viability after warm ischemia, preservation, and transplantation. N-acetylcysteine (NAC) is an antioxidant that has a direct effect on OFR, and is also a glutathione precursor, another antioxidant. This study was designed to evaluate the efficacy of NAC in preventing ischemia-reperfusion damage of liver grafts harvested from non-heart-beating donors. Liver transplantation was performed on pigs divided into five groups: group 1 (control group; n=5) received livers from heart-beating donors; livers were subjected to 30 min of warm ischemia in groups 2 (n=3, no NAC) and group 3 (n=3; NAC treatment); warm ischemia time lasted 60 min in groups 4 (n=4; no NAC) and 5 (n=5; NAC treatment). Studied parameters included graft survival for more than 3 days, aspartate aminotransferase plasma levels, liver histology, and hepatic total glutathione concentrations. Graft survival was 100% in groups 1, 2, and 3, 0% in group 4, and 20% in group 5. NAC treatment did not influence initial mean aspartate aminotransferase release which was greater in warm ischemic livers than in controls. NAC treatment had no effect on liver hepatic total glutathione after reperfusion of animals receiving warm ischemic grants. Finally, no effect on liver histology was observed with NAC treatment. Our study suggests that in liver transplantation from non-heart-beating donors, NAC has no effect in both graft viability and lipid peroxidation. The role of OFR in primary dysfunction of transplanted warm ischemic livers remains controversial.

Acetylcysteine↗
PubMed1999

[Congenital absence of portal vein in a girl with biliary atresia treated with liver transplant].

The congenital absence of the portal vein is a rare malformation, which has been generally discovered in association with another anomalies like a cardiac, gastrointestinal or genitourinary defects. With portal hypertension and hepatic cirrhosis, this anomaly is similar to spontaneous porto-systemic derivation, and for that not collateral venous drainage is present. In these patients, total interruption of mesentaric venous drainage during procurement of liver transplant produce a very important bowel and mesenteric edema, which can promote an injert fatal evolution. The authors present the first paediatric liver transplant, in a patient with portal venous agenesia, with de piggy-back technique was done and this complication was obviated, and a review of the literature about this issue is done.

Biliary Atresia↗
PubMed1998

Markers of cellular dysoxia during orthotopic liver transplantation in pigs.

OBJECTIVE: To characterize global, regional, and end-organ markers of cellular dysoxia during orthotopic liver transplantation and early reperfusion in pigs. DESIGN: Descriptive study. SETTING: University hospital research laboratory. ANIMALS AND INTERVENTIONS: 7 fasted, anesthetized, and mechanically ventilated Yorkshire pigs underwent orthotopic liver transplantation. Oxygen consumption (VO2) and oxygen delivery (DO2) were both calculated using standard formulae. Gastric interstitial pH and the gastroarterial partial pressure of carbon dioxide (PCO2) gradient were measured with a gastric tonometer. The following were determined from arterial blood samples: serum lactate to pyruvate ratio, serum 3-hydroxybutyrate to acetoacetate ratio, plasma free fatty acids, and plasma free and total carnitine levels. MEASUREMENTS AND RESULTS: Data were collected 1 h after induction of anesthesia (I), at the end of the anhepatic phase (A), and 1 h after reperfusion (R), Median (range) VO2 values obtained at the specified time points were: I 318 (206-1860), A 210 (152-408), R 330 (214-424) ml/kg per min, respectively (NS); DO2 values were: I 1828 (1382-3259), A 1219 (452-2492), R 1741 (1345-12,071) ml/kg per min, respectively (NS). The lactate to pyruvate ratio, reflecting the redox potential of the cytosol, progressively increased: I 22 (9-46), A 29 (16-68), R 43 (23-55), (p < 0.05). Gastric interstitial pH, as well as the gastroarterial PCO2 gradient values at the specified time points did not reach statistical significance. Levels of ketone bodies (3-hydroxybutyrate+acetoacetate) remained lower than 0.120 mmol/l. The ketone body ratio did not significantly vary over time (NS). Plasma esterified and free carnitine concentrations and free fatty acid values remained within normal limits (NS). Among these markers, the ketone body ratio presented the largest area under the receiver operating characteristic curve as a marker of postoperative mortality, with an inflexion point at 0.9. CONCLUSION: In this study, orthotopic liver transplantation was associated with significant variations over time in the redox potential of the cytosol. Postoperative mortality was, however, related to the redox state of the liver mitochondria. Our data suggest the occurrence of abnormal tissue oxygenation during liver transplantation.

3-Hydroxybutyric Acid↗
PubMed1998

Spleno-caval shunt in children using internal jugular vein graft: a case report.

Several techniques for decompression of portal hypertension have been described. The spleno-caval shunt is an easy and safe technique described in adult patients. However, the procedures described in adults are not adapted to children. We report an adaptation of this technique in a child, using the internal jugular vein as an interposition graft for relief of portal hypertension.

Child, Preschool↗
PubMed1997

Intrahepatic biliary-enteric bypass for complete extrahepatic biliary obstruction in children.

Intrahepatic biliary-enteric anastomosis is rarely practiced in pediatric surgery. The authors report on two children who have been successfully treated using this method. First described by Longmire and Sandford in 1948, intrahepatic biliary-enteric anastomosis is possible in children. This procedure is only indicated as a last recourse for circumstances in which the extrahepatic biliary tree is completely obstructed.

Anastomosis, Roux-en-Y↗
PubMed1997

[Intrahepatic glutathione and oxidative stress in liver transplantation in the pig].

OBJECT: To determine the loss of endogenous GSH from livers cold-stored and reperfused, using a model of liver transplantation in the pig. MATERIAL AND METHODS: Four female Yorkshire pigs weighing 19 to 40 kg received a liver allograft. Donor livers were cold-stored in the UW solution. Mean cold ischemic time was 6.5 hours. Malondialdehyde (MDA) levels were used as an index of oxidative stress. MDA plasma levels were measured following recipient laparotomy (H0), immediately (H1), and 90 minutes after liver reperfusion (H2). MDA and GSH levels in liver were measured following donor laparotomy (T0), at the end of cold ischemic period (T1), and at 90 minutes following liver reperfusion (T2). RESULTS: Three animals survived. MDA liver levels decreased of 44% between T0 and T1, then increased to 92% at T2. In contrast, in plasma, graft reperfusion was associated with an increase of MDA to 140% of the baseline values which reached 188% at H2. Intrahepatic GSH levels decreased of 49% at T1, then to 72% at T2. CONCLUSION: our study suggests that in liver transplantation: (1) Hepatic GSH is depleted to 49% during cold-storage, and an additional 23% is lost after reperfusion; (2) GSH contained in the UW solution does not prevent the loss of hepatocellular glutathione during preservation and reperfusion; (3) after short periods of cold ichemia, endogenous hepatic GSH may protect against oxydative stress in the transplanted liver.

Animals↗
PubMed1995

Liver retransplantation in children.

Between January 1988 and December 1993, 132 children received 154 orthotopic liver transplantation (OLT) at Bicêtre Hospital (France). Among them, 18 children underwent two and 2 children underwent three transplants (retransplant rate; 15.2%). Retransplantations were classified into three groups according to the interval between both OLTs: 1 (< 7 days, n = 8), 2 (8 days to 6 months, n = 10) and 3 (> 6 months, n = 4). Each group was compared with a control group whose grafts survived more than 1 week. There were no significant differences regarding age (35 +/- 49, 23 +/- 13, and 33 +/- 15 versus 49 +/- 41 months), cold ischemic time (566 +/- 105, 470 +/- 144, and 476 +/- 58 versus 455 +/- 110 minutes) and reduced size graft ratio (62.5%, 60%, and 75%, versus 58.3%). The causes of graft failure included primary nonfunctioning liver (PNF, n = 8) all in group 1 cases, biliary complications associated with hepatic artery thrombosis (HAT, n = 10; group 2, 6; group 3, 4), chronic rejection (n = 3; group 2, 1; group 3, 2) and three others (uncontrollable acute rejection, fulminant hepatitis, and secondary dysfunction, all in the group 2). The authors were unable to detect the cause of PNF. The overall survival rate after retransplantation was 62.5%, 60.0% and 75%, respectively. To reduce the rate of retransplants and improve the prognosis after OLT, further investigation into the cause of PNF, refinements in the anastomotic technique of the hepatic artery, and also early treatment of HAT are some of the goals to be achieved.

Adolescent↗
PubMed1994

Outcome of ABO-incompatible liver transplantation in children with no specific alloantibodies at the time of transplantation.

The shortage of suitable liver donors for children has motivated the use of ABO-incompatible (ABO-I) grafts for transplantation in urgent situations. However, survival after ABO-I liver grafts has been reported at about 30% as compared with 80% in cases of ABO-identical or -compatible liver grafts. This difference has been attributed to antibody-mediated, hyperacute or chronic liver rejection, due to preformed ABO antibodies (alloantibodies). In this study, we report our results with ABO-I livers in children without alloantibodies at the time of transplantation. From January 1988 to June 1993, 143 OLT were performed in 122 children. Eight children received 8 ABO-I liver grafts. Of these, 7 patients were included in the study. All 7 were alloantibody free before OLT. Five children were spontaneously alloantibody free, while in 2 children, the plasma alloantibodies were eliminated before and after transplantation using intravenous infusion of specific blood group antigens of the donor blood group (soluble antigens). Immunosuppression consisted of a triple-drug treatment combining CsA, AZA, and steroids. The follow-up period was between 10 and 48 months. One child died from a surgical complication. Six children survived, but 1 died 10 months later from intestinal obstruction. There were no graft losses and no episodes of hyperacute or chronic rejection. The graft and patient survival rate was 71%. There was a 28% incidence of rejection, but all were mild (requiring steroid boluses only). Our results suggest that the absence of ABO alloantibodies at the time of and after transplantation can protect ABO-I liver grafts against antibody-mediated rejection, whether hyperacute or chronic, and that soluble antigens are effective in eliminating alloantibodies in children.

ABO Blood-Group System↗
PubMed1994

Lessons from the first 100 liver transplantations in children at Bicêtre Hospital.

The authors report their experience with 100 liver transplantations at Bicêtre Hospital. From 1988 to 1991, 85 children received a total of 100 liver grafts (mean age, 44.4 months; two thirds were under 3 years of age). Fifty-four percent of the grafts were reduced-size. Cyclosporine, steroids, and azathioprine were used for immunosuppression. The actuarial survival rate at 4 years is 86%. Retransplantation was performed in 14 children (16%). Forty-four patients (49%) had another operation. Biliary complications (17%), hepatic artery thrombosis (HAT) (14%), and hemoperitoneum (14%) were the most frequent surgical complications. Retransplantation was avoided in 50% of the patients who underwent urgent artery revision for thrombotic complications. It appeared that ABO-incompatible were better tolerated in children without ABO alloantibodies at the time of transplantation. The survival rates of ABO-identical, -compatible, and -incompatible liver grafts did not differ (61%, 50%, and 57% respectively). The results suggest that an aggressive policy of reintervention, including retransplantation, is necessary to achieve a satisfactory survival rate and quality of life. Children lacking ABO alloantibodies at the time of transplantation might tolerate ABO-incompatible liver grafts better.

ABO Blood-Group System↗
PubMed1994

[Vascular complications of liver transplantation: surgical treatment].

Vascular complications constitute a major cause of morbidity and mortality after liver transplantation. They are dominated by arterial complications, the most frequent being hepatic artery thrombosis. Venous complications essentially consist of portal vein thrombosis. The preventive treatment of vascular complications is based on a better understanding of the risk factors. Close cooperation between surgeon, and radiologist is essential for effective surgical correction, which requires a rapid diagnosis and is designed to save not only the patient's life, but also, whenever possible, the liver transplant.

Aneurysm, False↗
PubMed1993

[Transplantation of reduced-size livers in children].

Nowadays, liver reduction techniques make it possible to use livers obtained from adults or adolescents for implantation in children. These techniques have been evaluated by analysis of 100 liver transplantations performed between January 1988 and October 1991 in 85 children. Forty-six full-size grafts implanted in 38 children (group 1) were compared with 54 reduced-size grafts implanted in 47 children (group 2). The overall actuarial survival at 4 years was 86 percent. There was no statistical significant difference between the two groups as regards the rates of death (8 versus 19 percent), reoperation (54 versus 64 percent), retransplantation (15 versus 16 percent), hepatic artery thrombosis (13 versus 15 percent) and graft survival (82 versus 70 percent) respectively. Haemorrhage was significantly more frequent in group 1 than in group 2 (P = 0.04), irrespective of whether transplantation was performed urgently or electively. Using reduced-size livers considerably increases the number of liver grafts available to children. Apart from a greater risk of haemorrhage, the results obtained with reduced-size livers were identical with those obtained with full-size livers.

Adolescent↗
PubMed1993

Pediatric liver transplantation for primary hepatocellular carcinoma associated with hepatitis virus infection.

We report two cases of early primary hepatocellular carcinoma (PHC) in children, after probable maternal transmission of hepatitis B, that were treated with orthotopic liver transplantation (OLT). Both children were 8.5 years old and had elevated levels of serum alpha-feto-protein. The diagnosis of PHC was made at 8 years and confirmed histologically. Serum hepatitis B surface antigen (HBs Ag) was detected in the mothers and suggested vertical transmission. An attempt at complete liver tumor resection failed, leading to OLT. In order to prevent recurrence of the hepatitis B virus (HBV) infection, hepatitis B immunoprophylaxis was used. Two years after OLT, one child presented with recurrent HBV infection. No tumor recurrence was observed at follow-up in either of the patients. From these two cases we conclude that (1) HBV infection may play an important causal role in PHC in children, with an even shorter incubation period than that in adults; (2) close follow-up is needed for children who are HBs Ag-positive carriers; and (3) liver transplantation should be proposed early after the diagnosis of PHC, when tumor resection is not feasible.

Carcinoma, Hepatocellular↗
PubMed1993

[Surgery of liver transplantation in children].

From 1988 until 1992, 94 children with end-stage liver disease were put forward for orthotopic liver transplantation (OLT) by the surgical and anesthesic teams of the Bicetre Hospital. Due to a majority of adult donors, and to the young age of the recipients (mean = 3 years 3 months), a reduced-size graft was prepared in 64 out of the 111 transplants performed (58%). A number of children (42) had to be reoperated on due to complications: hepatic artery thrombosis, one of the most severe complications following pediatric OLT, occurred in 14 cases, and was an indication for seven out of the 17 retransplantations in this series. The eight deaths which occurred in the early postoperative period were the toll of this particularly challenging surgery.

Adolescent↗