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Dive into the research topics where Nigel Heaton is active.

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Featured researches published by Nigel Heaton.


American Journal of Transplantation | 2004

Efficacy and safety of valganciclovir vs. oral ganciclovir for prevention of cytomegalovirus disease in solid organ transplant recipients.

Carlos V. Paya; Atul Humar; Ed Dominguez; Kenneth Washburn; Emily A. Blumberg; Barbara D. Alexander; Richard B. Freeman; Nigel Heaton; Mark D. Pescovitz

We compared the efficacy and safety of valganciclovir with those of oral ganciclovir in preventing cytomegalovirus (CMV) disease in high‐risk seronegative solid organ transplant (SOT) recipients of organs from seropositive donors (D+/R‐). In this randomised, prospective, double‐blind, double‐dummy study, 364 CMV D+/R‐ patients received valganciclovir 900 mg once daily or oral ganciclovir 1000 mg three times a day (tid) within 10 days of transplant and continued through 100 days. CMV disease, plasma viremia, acute graft rejection, graft loss and safety were analyzed up to 6 and 12 months post‐transplant. Endpoint committee‐defined CMV disease developed in 12.1% and 15.2% of valganciclovir and ganciclovir patients, respectively, by 6 months, though with a difference in the relative efficacy of valganciclovir and ganciclovir between organs (i.e. an organ type‐treatment interaction). By 12 months, respective incidences were 17.2% and 18.4%, and the incidence of investigator‐treated CMV disease events was comparable in the valganciclovir (30.5%) and ganciclovir (28.0%) arms. CMV viremia during prophylaxis was significantly lower with valganciclovir (2.9% vs. 10.4%; p = 0.001), but was comparable by 12 months (48.5% valganciclovir vs 48.8% ganciclovir). Time‐to‐onset of CMV disease and to viremia were delayed with valganciclovir; rates of acute allograft rejection were generally lower with valganciclovir. Except for a higher incidence of neutropenia with valganciclovir (8.2%, vs 3.2% ganciclovir) the safety profile was similar for both drugs. Overall, once‐daily oral valganciclovir was as clinically effective and well‐tolerated as oral ganciclovir tid for CMV prevention in high‐risk SOT recipients.


The Lancet | 1998

De-novo autoimmune hepatitis after liver transplantation.

Nanda Kerkar; Nedim Hadzic; E T Davies; Bernard Portmann; Peter T. Donaldson; Mohamed Rela; Nigel Heaton; Diego Vergani; Giorgina Mieli-Vergani

Summary 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), Alagilles syndrome (one), drug-induced acute liver failure (one), and α1-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.


Gut | 2012

Guidelines for the diagnosis and treatment of cholangiocarcinoma: an update.

Shahid A. Khan; Brian R. Davidson; Robert Goldin; Nigel Heaton; John Karani; Stephen P. Pereira; William Rosenberg; Paul Tait; Simon D. Taylor-Robinson; Andrew V. Thillainayagam; Howard C. Thomas; Harpreet Wasan

The British Society of Gastroenterology guidelines on the management of cholangiocarcinoma were originally published in 2002. This is the first update since then and is based on a comprehensive review of the recent literature, including data from randomised controlled trials, systematic reviews, meta-analyses, cohort, prospective and retrospective studies.


Transplantation | 2004

Hepatocyte transplantation for inherited factor VII deficiency.

Anil Dhawan; Ragai R. Mitry; Robin D. Hughes; Sharon C. Lehec; Claire Terry; Sanjay Bansal; Rupen Arya; Jim Wade; Anita Verma; Nigel Heaton; Mohamed Rela; Giorgina Mieli-Vergani

Hepatocyte transplantation has been investigated in patients with liver-based metabolic disorders and acute liver failure. We report the first use of hepatocyte transplantation in two brothers with severe inherited coagulation factor VII deficiency. Patient 1 received a total of 1.09x10(9) cryopreserved hepatocytes, and patient received 2.18x10(9) fresh and cryopreserved hepatocytes through a Hickman line inserted in the inferior mesenteric vein. Infusion of isolated human hepatocytes improved the coagulation defect and markedly decreased the requirement for exogenous recombinant factor VII (rFVIIa) to approximately 20% of that before cell transplantation. In both patients, episodes of line sepsis were associated with an increase in rFVIIa requirement. Six months posthepatocyte transplantation, higher rFVIIa doses were required, suggesting loss of transplanted hepatocyte function. Because of increasing problems with venous access and long-term uncertainty of the efficacy of hepatocyte transplantation, orthotopic liver transplantation was performed successfully in both cases.


Transplantation | 1998

Progressive cardiac amyloidosis following liver transplantation for familial amyloid polyneuropathy - Implications for amyloid fibrillogenesis

A. J. Stangou; Philip N. Hawkins; Nigel Heaton; M. Rela; Mark Monaghan; Petros Nihoyannopoulos; J. O'Grady; Mark B. Pepys; Roger Williams

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.


Transplantation | 2002

The role of mitochondria in ischemia/reperfusion injury

Wayel Jassem; Susan V. Fuggle; Mohamed Rela; Dicken D.H. Koo; Nigel Heaton

In organ transplantation, ischemia/reperfusion injury is a multifactorial process that leads to organ damage and primary graft dysfunction. Injury to the organ is mediated by a complex chain of events that involves depletion of energy substrates, alteration of ionic homeostasis, production of reactive oxygen species, and cell death by apoptosis and necrosis. There is increasing evidence that mitochondria play a role in this process because of the profound changes experienced during ischemia and reperfusion. Understanding the mechanisms that lead to mitochondrial damage may be important for developing strategies aimed at improving graft outcome. In this review, we examine the role of mitochondria in ischemia/reperfusion injury and the possible mechanisms that may contribute to organ dysfunction.


Annals of Surgery | 1998

Split liver transplantation: King's College Hospital experience.

Mohamed Rela; V. Vougas; Paolo Muiesan; Hector Vilca-Melendez; Vassilis Smyrniotis; Paul Gibbs; John Karani; Roger Williams; Nigel Heaton

BACKGROUND The purpose of split liver transplantation is to increase the source of pediatric grafts without compromising the adult donor pool. Early results have been discouraging because of technical complications and selection of poor risk patients. METHODS The results of a single center experience of 41 split liver transplantations were analyzed. Patient and graft survival and complications related to the technique were analyzed. RESULTS Patient and graft survival for the whole group was 90% and 88% respectively at a median follow up of 12 months (range 6-70 months). Patient and graft survival for the right lobe graft was 95% and the left lateral segment 86% and 82% respectively. Four patients died, of which two of the patients were first two splits following technical complications. Two others died, one from cerebral lymphoma and the other of multiorgan failure secondary to sepsis. One patient has been retransplanted for chronic biliary sepsis. CONCLUSION Split liver transplantation has now become an acceptable treatment option for both adult and pediatric recipients with end stage liver disease. Right lobe recipients are not disadvantaged by the procedure. Good results can be achieved with better patient selection and by the use of good quality organs.


The Journal of Infectious Diseases | 2004

Absence of Cytomegalovirus-Resistance Mutations after Valganciclovir Prophylaxis, in a Prospective Multicenter Study of Solid-Organ Transplant Recipients

Guy Boivin; Nathalie Goyette; Christian Gilbert; Noel Allan Roberts; Katherine Macey; Carlos V. Paya; Mark D. Pescovitz; Atul Humar; Ed Dominguez; Kenneth Washburn; Emily A. Blumberg; Barbara D. Alexander; Richard B. Freeman; Nigel Heaton; Emma Covington

We investigated the emergence of cytomegalovirus (CMV) ganciclovir-resistance mutations in 301 high-risk solid-organ transplant (SOT) recipients after oral prophylaxis, for 100 days, with either valganciclovir or ganciclovir. For patients treated with ganciclovir, the incidence of CMV UL97 mutations was 1.9% (2/103) at the end of prophylaxis and 6.1% (2/33) for patients with suspected CMV disease up to 1 year after transplantation. No resistance mutations were detected in samples from valganciclovir-treated patients. Dual polymerase (UL54) and UL97 resistance mutations were not seen. Valganciclovir was associated with negligible risk of resistance and thus constitutes a useful alternative to ganciclovir prophylaxis for CMV in high-risk SOT recipients.


Annals of Surgery | 2005

Single-center experience with liver transplantation from controlled non-heartbeating donors: a viable source of grafts.

Paolo Muiesan; Raffaele Girlanda; Wayel Jassem; Hector Vilca Melendez; John O'Grady; Matthew Bowles; Mohamed Rela; Nigel Heaton

Background:To increase the number of livers available for transplantation a non-heartbeating donor (NHBD) liver transplant program was started after obtaining hospital ethical committee approval. Methods:Controlled donors with a warm ischemia of <30 minutes were considered. A 5-minute stand-off period was observed from asystole to skin incision. A super-rapid technique was used for the retrieval. Methods used to assess the suitability for transplantation included liver function tests, morphologic and histologic assessment, and hepatocyte viability testing. Results:Sixty livers were retrieved from NHBDs. Of these, 33 were judged suitable for transplantation. Of these one was exported and transplanted, and one could not be matched to a suitable recipient. A further 27 were not used because of liver appearance in 21, prolonged hypoxia and hypotension in 4, poor perfusion in 1, and donor malignancy in 1. Mean donor age was 39.4 years (range, 0.75–67 years). Causes of death were head trauma in 10 donors, intracranial bleed in 24, and anoxic/ischemic brain injury in 26. Mean warm ischemia time was 14.7 minutes (range, 7–40 minutes). Thirty-two patients were transplanted (one split liver), and the mean age of the recipients was 38.4 years (range, 0.7–72 years). All grafts had good early function except one right lobe split. There were 4 deaths resulting from ischemic brain injury, chronic rejection, biliary sepsis, and multiorgan failure following retransplantation for primary nonfunction. Overall patient and graft survival is 87% and 84%, respectively, at a median follow-up of 15 months. Conclusions:Early results suggest that controlled NHBDs are a significant new source of grafts, but careful donor selection and short cold ischemia are mandatory.


Journal of Hepatology | 2013

Lessons from look-back in acute liver failure? A single centre experience of 3300 patients.

William Bernal; Anna Hyyrylainen; Amit Gera; Vinod K. Audimoolam; Mark McPhail; Georg Auzinger; Mohammed Rela; Nigel Heaton; John O’Grady; Julia Wendon; Roger Williams

BACKGROUND & AIMS Acute liver failure (ALF) is a rapidly progressive critical illness with high mortality. Complex intensive care unit (ICU) protocols and emergency liver transplantation (ELT) are now often available, but rarity and severity of illness have limited its study and evidence-base for care. We reviewed patients treated over a 35-year period at a specialist high-volume ICU, quantifying changes in disease aetiology, severity and evolution of ICU support and ELT use and outcome. METHODS Review of adult patients admitted during the period 1973-2008, with acute liver dysfunction and coagulopathy with overt hepatic encephalopathy (ALF) and those without (acute liver injury; ALI). RESULTS 3305 patients fulfilled inclusion criteria, 2095 with ALF. Overall hospital survival increased from 30% in 1973-78 to 76% in 2004-08; in ALF from 17% to 62% (both p<0.0001). In ALF patients treated without ELT, survival rose from 17% to 48% (p<0.0001); in those undergoing ELT (n=387) from 56% in 1984-88 to 86% in 2004-08 (p<0.01). Coincident with drug sales-restriction, paracetamol-related admissions fell significantly. Viral admissions fell from 56% to 17% of non-paracetamol cases (p<0.0001). Admission markers of liver injury severity fell significantly and the proportion of patients with intracranial hypertension (ICH) fell from 76% in 1984-88 to 20% in 2004-08 (p<0.0001). In those with ICH, mortality fell from 95% to 55% (p<0.0001). CONCLUSIONS The nature and outcome of ALF have transformed over 35 years, with major improvements in survival and a fall in prevalence of cerebral oedema and ICH, likely consequent upon earlier illness recognition, improved ICU care, and use of ELT.

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Mohamed Rela

University of Cambridge

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John O'Grady

University of Cambridge

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Anil Dhawan

University of Cambridge

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Paolo Muiesan

Queen Elizabeth Hospital Birmingham

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M. Rela

University of Cambridge

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Julia Wendon

University of Cambridge

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Wayel Jassem

University of Cambridge

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