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Biomedical subjects

N D Heaton

Publications and source records attributed to N D Heaton.

At least 55 records · Page 3Linked to original sources
PubMed1999

Oral absorption of tacrolimus in children with intestinal failure due to short or absent small bowel.

We describe two children with intestinal failure due to short or absent small bowel who underwent isolated liver transplantation for liver disease related to parenteral nutrition. Both received reduced-size liver grafts whilst awaiting a suitable small bowel donor. Immunosuppressive therapy was based on oral tacrolimus and intravenous steroids. Therapeutic levels of tacrolimus were achieved at low dosage of 0.14-0.28 mg/kg per day. Median and mean blood tacrolimus levels were 9.9 and 13.7 ng/ml (range 4.9-42.3 ng/ml) in case 1 and 5.8 and 7.2 ng/ml (range 1-30 ng/ml) in case 2 before small bowel transplantation, respectively. Following small bowel transplantation, levels were 17.1 and 20.1 ng/ml (range 9.2-30 ng/ml), with oral doses of 0.54-1.35 mg/kg per day. Both children died of adenovirus pneumonia, with functioning grafts. Our experience demonstrates that effective levels of immunosuppression can be achieved by oral administration of tacrolimus in children with short or absent small bowel.

Adenoviridae Infections↗
PubMed1999

Liver transplantation with monosegments.

BACKGROUND: Shortage of size-matched pediatric donors led to the development of surgical techniques to reduce or split livers and thus increase the potential pool of donors. Despite this, neonatal transplantation remains a problem because of the small size of the recipients. Further reduction of the left lateral segment is possible to provide a single segment graft (segment III). We report our experience of transplanting 6 babies using this technique. METHODS: Of 310 children transplanted in our center between October 1989 and March 1998, 6 patients, 2 male and 4 female, median age 37.5 days (range 5 to 92 days), median weight 3.45 kg (range 2.45 to 5.46 kg) were transplanted with a monosegment. The cause of liver failure was neonatal hemochromatosis in 4, retransplantation for hepatic artery thrombosis in 1, and hepatitis B in one. The donor liver was reduced or split to a left lateral segment. Segment II was then resected and discarded before transplantation. RESULTS: Overall, graft and patient survival is 83.3%. Five patients are alive with good graft function at a mean follow-up of 30.4 months (range 8 to 82 months). One child who was transplanted for hepatic artery thrombosis died from sepsis and multiorgan failure 48 hrs after transplant. None of the survivors had vascular or biliary complications. CONCLUSIONS: Monosegment liver transplantation with segment III appears to be a satisfactory option for treating small babies with liver failure.

Female↗
PubMed1999

Auxiliary partial orthotopic liver transplantation for Crigler-Najjar syndrome type I.

OBJECTIVE: To determine if auxiliary partial orthotopic liver transplantation (APOLT) has the long-term potential to correct the underlying abnormality in Crigler-Najjar syndrome type 1 (CNS1) without the need for total liver replacement. BACKGROUND: Orthotopic liver transplantation has been used successfully to replace the defective enzyme in CNS1. Experimental studies have shown that only 1% to 2% of the normal hepatocyte mass is needed for bilirubin conjugation. If APOLT corrects the underlying metabolic abnormality, it has the advantage of preserving the native liver, which would serve as a "safety net" should the graft fail, and there is the potential for gene therapy in the future with possible withdrawal of immunosuppression. METHODS: Seven APOLT procedures were performed in six recipients with CNS1. Median age at transplantation was 10.5 years. Six transplants were performed as a left auxiliary liver transplant, and one was performed as a right auxiliary liver transplant. Median serum bilirubin level at transplantation was 320 micromol/L. All patients required 12 to 16 hours of phototherapy daily before the transplant to maintain serum bilirubin levels between 250 and 350 micromol/L. RESULTS: Median serum bilirubin level was 50 micromol/L at day 5 after the transplant and 23 micromol/L at a median follow-up of 32 months. In four children, early severe acute rejection developed, requiring conversion to tacrolimus; one underwent a second transplant for chronic rejection and graft atrophy but died from lymphoproliferative disease 6 months after the second transplant. CONCLUSIONS: This report shows that APOLT is technically feasible and provides adequate hepatocyte mass to correct the underlying metabolic abnormality in CNS1.

Adolescent↗
PubMed1998

Accessory right hepatic artery arising from the left: implications for split liver transplantation.

BACKGROUND: Variant arterial anatomy must be recognized and appropriately managed during split liver transplantation to ensure complete vascular supply to both grafts. We describe an accessory posterior right hepatic artery, arising from the left and passing behind the portal vein bifurcation. METHODS: Thirty-seven consecutive livers were examined during ex vivo liver-splitting procedures. An abnormal right accessory artery arising from the left hepatic artery was identified high in the porta hepatis. The anatomical variant is described and illustrated by methylene blue injection and arteriography. RESULTS: The anomaly was encountered in 2 of 37 split liver procedures. The two right lobes with the abnormal artery were discarded. CONCLUSION: Care should be taken during dissection behind the portal vein bifurcation to exclude an accessory segmental right hepatic artery. If present, the liver may not be suitable for splitting without compromising the right lobe, unless the left hepatic artery can be divided distal to the origin of the accessory vessel.

Hepatic Artery↗
PubMed1998

Hemophagocytosis: a potential complication in small bowel transplantation.

BACKGROUND: Acquired hemophagocytosis is a histiocytic proliferation associated with phagocytosis of the hemopoietic elements resulting in fever, profound pancytopenia, hepatosplenomegaly, lymphadenopathy, and coagulopathy. Acquired hemophagocytic syndrome is a specific entity that can be differentiated from malignant histiocytosis and familial hemophagocytosis. It has been associated with a variety of disorders, including immunodeficiency, infection, hemopathies, cancer, and autoimmune diseases, as well as with the period following solid organ and bone marrow transplantation. METHODS: We describe a case of a fatal outcome, due to hemophagocytosis, after small bowel transplantation in a patient with systemic lupus erythematosus. RESULTS: Hemophagocytosis secondary to systemic lupus erythematosus has been reported to have a better response to steroid therapy than that associated with infection. In this case, the association of an autoimmune disease, high levels of immunosuppression, and posttransplant sepsis may have triggered the onset of hemophagocytosis. CONCLUSION: It is suggested that patients with systemic lupus erythematosus may represent a high-risk group for developing hemophagocytosis after small bowel transplantation.

Fatal Outcome↗
PubMed1998

Gender matching and outcome after pediatric liver transplantation.

BACKGROUND: Gender is not a selection criterion for orthotopic liver transplantation (OLT), and reports in adults have shown a less favorable outcome for male recipients of female organs; the only pediatric study did not support this finding. The aim of the present study was to assess the impact of donor and recipient gender on graft and patient survival rates after pediatric OLT. METHODS: We have reviewed retrospectively 137 children (male=63; median age: 3.4 years; range: 14 days to 15 years) undergoing primary OLT from January 1991 to June 1996. These children were divided into donor-recipient gender match (M; n=64) and nonmatch (NM; n=73) groups and then classified into female to female (FF; n=30), female to male (FM; n=29), male to female (MF; n=44), and male to male (MM; n=34) subgroups. RESULTS: The M group had better graft and patient survival rates at both 1- and 5-year follow-up compared with the NM group (P<0.01). Graft and patient survival rates were different among gender subgroups (P<0.04). Graft and patient survival rates in the FM group were poorer than in the MM subgroup at both 1 and 5 years (P<0.03, P<0.01). The FM group had a higher incidence of early complications than the MM (P<0.01) group, with 50% and 33% of graft losses, respectively, related to the complications. To minimize the influence of hormonal factors, we have analyzed separately the patients younger than 12 and 10 years who had similar findings. CONCLUSION: Graft and patient survival rates after pediatric OLT are worse in gender mismatch groups, particularly for male recipients of female organs. Early complications play a role in the decreased survival rates.

Adolescent↗
PubMed1998

Progressive cardiac amyloidosis following liver transplantation for familial amyloid polyneuropathy: implications for amyloid fibrillogenesis.

BACKGROUND: Circulating transthyretin (TTR) is derived from the liver, and orthotopic liver transplantation (OLT) is widely performed for variant TTR-associated familial amyloid polyneuropathy (FAP). The effect of OLT on FAP-related cardiac amyloid is of particular interest because wild-type TTR can itself be deposited as senile cardiac amyloid. METHODS: Serial echocardiography was performed in 20 FAP patients, 14 of whom underwent OLT, and 10 other liver transplant patients. Follow-up included serum amyloid P component scintigraphy and measurement of plasma TTR before and after OLT. RESULTS: Cardiac amyloidosis progressed rapidly in three FAP patients (TTR Pro52 and Thr84 mutations) after OLT, even though the deposits elsewhere had stabilized or regressed. Results of echocardiography improved in three transplant patients with TTR Met30 and remained normal in seven other patients. Plasma TTR levels were altered substantially after OLT, but they did not reflect the cardiac findings. CONCLUSIONS: Although amyloid deposition in FAP is generally inhibited after OLT, cardiac amyloidosis can be exacerbated, probably due to enhanced deposition of wild-type TTR on a template of amyloid derived from variant TTR. The phenomenon may be mutation-dependent. These findings suggest that amyloid formation de novo and its subsequent accumulation can be promoted by different factors, which may be organ-specific.

Amyloid Neuropathies↗
PubMed1998

Domino hepatic transplantation using the liver from a patient with familial amyloid polyneuropathy.

BACKGROUND: In transplantation, novel methods are required to augment the supply of donor organs. We report the first domino liver transplant in which a patient with familial amyloid polyneuropathy (FAP) received an orthotopic split liver graft, and her explanted liver was donated to another patient. Three successful liver transplants were thus achieved from the one cadaver liver. PATIENTS AND METHODS: A cadaveric donor liver was split and the left lobe was grafted into a child with biliary atresia. The right lobe was transplanted into a woman with FAP associated with the transthyretin Met30 variant. Her own otherwise healthy liver was donated to a patient with cirrhosis and hepatocellular carcinoma. RESULTS: Fifteen months after transplantation, all three recipients are well with normal liver function. The domino recipient developed inferior vena cava stricturing at the level of anastomosis after surgery with resultant ascites, requiring dilatation and LeVeen shunt insertion. Serum amyloid P component scintigraphy showed amyloid regression in the domino donor and to date has not identified any amyloid deposits in the recipient, who also remains free of tumor recurrence. CONCLUSIONS: Domino transplantation using the livers from patients with FAP may be justified for patients whose disease condition precludes a long spell on the waiting list, including those with hepatic malignancies and those for whom palliation rather than long-term cure is the aim.

Adult↗
PubMed1998

De-novo autoimmune hepatitis after liver transplantation.

BACKGROUND: Late graft dysfunction that does not result from recognised causes, such as rejection, infection, or vascular or biliary complications, can occur after liver transplantation. We investigated a particular type of unexplained graft dysfunction that is associated with autoimmune features in children who underwent transplantation at our unit between 1991 and 1996. METHODS: Seven (4%) of 180 liver-transplant recipients developed an unexplained but characteristic form of graft dysfunction (five boys, two girls; median age at presentation 10.3 years, range 2.0-19.4). The median period after surgery was 24 months (6-45). The indications for transplantation had been extrahepatic biliary atresia (four patients), Alagille's syndrome (one), drug-induced acute liver failure (one), and alpha1-antitrypsin deficiency (one). Four patients were on triple immunosuppression with cyclosporin, azathioprine, and prednisolone; and three were on tacrolimus. Immunoglobulin measurements, autoantibody studies, serological studies, and HLA typing were undertaken. Liver-biopsy samples were taken. FINDINGS: Infectious and surgical complications were excluded. Liver-biopsy samples showed the histological changes of chronic hepatitis, including portal and periportal hepatitis with lymphocytes and plasma cells, bridging collapse, and perivenular-cell necrosis without changes typical of acute or chronic rejection. All patients had high concentrations of IgG (median 22 g/L [range 17.2-34.4]) and high titres of autoantibodies. All but one patient responded to prednisolone 2 mg/kg daily and an increase in or addition of azathioprine (1.5 mg/kg daily) within a median of 32 days (7-316). One responder relapsed owing to poor compliance but went into remission after treatment was restored. All six respondents remain in remission on a reduced dose of prednisolone (5-10 mg/day) and 1.5 mg/kg daily azathioprine at a median of 283 days (range 108-730) follow-up. INTERPRETATION: Our data show that symptoms of autoimmune hepatitis, which are responsive to the classical treatment for this condition, can appear in liver-transplant patients while they are on anti-rejection immunosuppression. Whether the liver damage in these patients is a form of rejection or the consequence of autoimmune attack has yet to be established.

Anti-Inflammatory Agents↗
PubMed1998

A validated technique for the analysis of biliary bile acid secretion in donor livers prior to transplantation.

Many parameters currently used for the pre-transplant assessment of liver allografts, are not reliable enough in predicting the likelihood of early graft dysfunction or non-function. It is generally accepted that bile secretion is a sign of hepatic function post-transplant and that bile flow shows a close linear relationship to the secretion of bile acids ("apparent choleretic activity"). We have studied bile flow, biliary bile acid concentrations and composition and measured apparent choleretic activity from hepatic bile collected with a new technique under controlled conditions at the time of retrieval from 18 donor livers. More than three samples were collected from each of 13 donors and a total of 65 samples of hepatic bile were analysed. Of these, ten showed typical apparent choleretic activity with a positive slope in the regression line analysis (correlation coefficient of 0.9), validating our collection technique.

Adolescent↗
PubMed1998

Diaphragmatic nerve palsy in young children following liver transplantation. Successful treatment by plication of the diaphragm.

Diaphragmatic paralysis was identified in four children after liver transplantation. All presented with persistent right upper lobe atelectasis, pleural effusion and recurrent respiratory infections and could not be weaned from mechanical ventilatory support. Fluoroscopy and real-time ultrasound confirmed paradoxical right diaphragmatic movements. Diaphragmatic plication was undertaken and enabled rapid and sustained weaning from respiratory support in all four cases. Vascular clamping of the suprahepatic vena cava seems to be the cause. Diaphragmatic plication allows optimal recruitment of the respiratory muscles with a favourable impact on lung mechanics and gas exchange.

Child, Preschool↗
PubMed1998

Bowel perforation after paediatric orthotopic liver transplantation.

Bowel perforation is a well-recognized complication following orthotopic liver transplantation. Of 194 paediatric liver transplantations performed in our hospital, 13 patients (6.7%) developed bowel perforation post-transplantation. Contributory factors included previous operation, steroid therapy and viral infection. The incidence was higher in children who underwent transplantation for biliary atresia after a previous Kasai portoenterostomy. Seven patients (53% of this group) reperforated. Diagnosis may be difficult and a high index of suspicion is needed.

Child↗
PubMed1998

Laparoscopic cholecystectomy injury: an unusual indication for liver transplantation.

The introduction of laparoscopic cholecystectomy has been associated with a rise in the number of reported bile duct injuries (0.3%-0.8%). Significant vascular injuries are rare (0.16%), but may lead to life-threatening complications. We present a case report of a patient undergoing transplantation for a laparoscopic cholecystectomy injury.

Adult↗
PubMed1998

Anti-thymocyte globulin, cyclosporin A and granulocyte colony-stimulating factor for severe aplastic anaemia complicating paediatric liver transplantation.

UNLABELLED: We describe a sustained trilineage haematopoietic response to intensified immunosuppressive therapy with anti-thymocyte globulin, cyclosporin A and recombinant human granulocyte colony-stimulating factor in a 4-year-old girl, who developed severe aplastic anaemia after orthotopic liver transplantation for fulminant liver failure induced by non A-E hepatitis. The outcome was successful and allows the following. CONCLUSION: Intense immunosuppression in combination with haemopoetic growth factors and antimicrobial prophylaxis should be considered as first line therapy in severe aplastic anaemia after orthotopic liver trans-plantation.

Anemia, Aplastic↗