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Dive into the research topics where P. McMaster is active.

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Featured researches published by P. McMaster.


The Lancet | 1996

Lamivudine prophylaxis against reinfection in liver transplantation for hepatitis B cirrhosis

Leonie Grellier; David Mutimer; Monz Ahmed; D. Brown; Andrew K. Burroughs; Keith Rolles; P. McMaster; P Beranek; F Kennedy; H Kibbler; P McPhillips; Elwyn Elias; Geoff Dusheiko

BACKGROUND Orthotopic liver transplantation in patients positive for hepatitis B virus (HBV) DNA is associated with a high reinfection rate, even with hepatitis B immunoglobulin (HBIG) prophylaxis. Nucleoside analogues that inhibit hepatitis B replication in patients with chronic hepatitis B could prevent reinfection after transplantation. The aim of this study was to analyse the efficacy and safety of prophylaxis both before and after transplantation with the nucleoside analogue lamivudine, without HBIG, in patients undergoing liver transplantation. METHODS 17 HBsAg-positive patients with decompensated cirrhosis and previous evidence of viral replication were enrolled. 12 were HBV-DNA-positive by a signal amplification assay. Patients were treated with oral lamivudine (100 mg daily) for at least 4 weeks before transplantation and followed up for 18-90 weeks after transplantation. FINDINGS HBV DNA became undetectable in serum before transplantation in all HBV-DNA-positive patients. Four died before transplantation from complications of cirrhosis; one patient was withdrawn from the study because of a cerebrovascular accident. The remaining 12 patients underwent transplantation. Two patients died after transplantation (one at 3 days and one [suicide] at 20 weeks). HBV DNA reappeared in one patient with histological evidence of recurrent hepatitis (72 weeks). By week 24 the nine remaining patients had lost HBsAg and remained negative for HBV DNA. INTERPRETATION Lamivudine treatment may prove useful in preventing recurrence of hepatitis B after liver transplantation. The effect on survival of patients after transplantation remains to be assessed.


Transplantation | 2000

Portal vein thrombosis in adults undergoing liver transplantation: risk factors, screening, management, and outcome

Ma Yerdel; Bridget K. Gunson; Darius F. Mirza; K Karayalçin; S Olliff; J Buckels; David Mayer; P. McMaster; Jacques Pirenne

BACKGROUND Portal vein thrombosis (PVT) has been seen as an obstacle to liver transplantation (LTx). Recent data suggest that favorable results may be achieved in this group of patients but only limited information from small size series is available. The present study was conducted in an effort to review the surgical options in patients with PVT and to assess the impact of PVT on LTx outcome. Risk factors for PVT and the value of screening tools are also analyzed. METHODS Adult LTx performed from 1987 through 1996 were reviewed. PVT was retrospectively graded according to the operative findings: grade 1: <50% PVT +/- minimal obstruction of the superior mesenteric vein (SMV); grade 2: grade 1 but >50% PVT; grade 3: complete PV and proximal SMV thrombosis; grade 4: complete PV and entire SMV thrombosis. RESULTS Of 779 LTx, 63 had operatively confirmed PVT (8.1%): 24 had grade 1, 23 grade 2, 6 grade 3, and 10 grade 4 PVT. Being male, treatment for portal hypertension, Child-Pugh class C, and alcoholic liver disease were associated with PVT. Sensitivity of ultrasound (US) in detecting PVT increased with PVT grade and was 100% in grades 3-4. In patients with US-diagnosed PVT, an angiogram was performed and ruled out a false positive US diagnosis in 13%. In contrast with US, angiograms differentiated grade 1 from grade 2, and grade 3 from grade 4 PVT. Grade 1 and 2 PVT were managed by low dissection and/or a thrombectomy; in grade 3 the distal SMV was directly used as an inflow vessel, usually through an interposition donor iliac vein; in grade 4 a splanchnic tributary was used or a thrombectomy was attempted. Transfusion requirements in PVT patients (10 U) were higher than in non-PVT patients (5 U) (P<0.01). In-hospital mortality for PVT patients was 30% versus 12.4% in controls (P<0.01). Patients with PVT had more postoperative complications, renal failure, primary nonfunction, and PV rethrombosis. The overall actuarial 5-year patient survival rate in PVT patients (65.6%) was lower than in controls (76.3%; P=0.04). Patients with grade 1 PVT, however, had a 5-year survival rate (86%) identical to that of controls, whereas patients with grades 2, 3, and 4 PVT had reduced survival rates. The 5-year patient survival rate improved from the 1st to the 2nd era in non-PVT patients (from 72% to 83%; P<0.01), in grade 1 PVT (from 53% to 100%; P<0.01), and in grades 2 to 4 PVT (from 38% to 62%; P=0.11). CONCLUSIONS The value of US diagnosis in patients with PVT depends on the PVT grade, and false negative diagnoses occur only in incomplete forms of PVT (grades 1-2). The degree of PVT dictates the surgical strategy to be used, thrombectomy/low dissection in grade 1-2, mesoportal jump graft in grade 3, and a splanchnic tributary in grade 4. Taken altogether, PVT patients undergo more difficult surgery, have more postoperative complications, have higher in-hospital mortality rates, and have reduced 5-year survival rates. Analysis by PVT grade, however, reveals that grade 1 PVT patients do as well as controls; only grades 2 to 4 PVT patients have poorer outcomes. With increased experience, results of LTx in PVT patients have improved and, even in severe forms of PVT, a 5-year survival rate >60% can now be achieved.


The Lancet | 2000

Normalised intrinsic mortality risk in liver transplantation: European Liver Transplant Registry study

René Adam; Valérie Cailliez; Pietro Majno; Vincent Karam; P. McMaster; Roy Calne; John O'Grady; R. Pichlmayr; P. Neuhaus; Jean-Bernard Otte; Krister Hoeckerstedt; Henri Bismuth

BACKGROUND No model exists for liver transplantation to estimate the mortality risk in a given patient, and no standard by which to assess performance in different centres. We investigated the intrinsic mortality risk in the absence of known mortality risk factors. METHODS We identified mortality risk factors and risk ratios quantified in data from the European Liver Transplant Registry (22,089 patients at 102 centres in 18 countries) registered from 1988 to 1997. To develop a model of the intrinsic risk and the risk ratios for specific factors, univariate and multivariate analyses were done separately for the overall population, for adults, and for children younger than 15 years, and the number of deaths were estimated. We validated the model by comparing mortality in patients without risk factors with the model-adjusted mortality in patients with risk factors. FINDINGS Overall 5-year and 8-year actuarial survival was 66% (95% CI 65-66) and 61% (60-62). 65% of deaths occurred within 6 months. Retransplantation, transplantation for cancer, acute liver failure, fewer than 20 split-liver grafts per year, and a centre workload of fewer than 25 transplants per year were the main risk factors of 12 identified factors. 1-year and 5-year death rates among adults with no risk factors were similar to model estimates (15 [13-16] vs 14% [13-15], and 22 (20-24) vs 23% [21-24]). Corresponding data for paediatric transplants were 9% (7-12) compared with 11% (9-12) and 13% (10-17) compared with 14% (11-16). The reduction of mortality risk in high-volume centres was even greater in patients without risk factors (48 vs 23%, p<0.001). INTERPRETATION The normalised intrinsic mortality risk can be combined with the relative risk ratios of known risk factors to better estimate the mortality risk of a given procedure in a given patient. Centres can assess performance by removing potential bias of donor and recipient selection.


The Lancet | 1987

NEUROLOGICAL COMPLICATIONS FOLLOWING LIVER TRANSPLANTATION

D.H. Adams; Bridget K. Gunson; L. Honigsberger; J. Buckels; S. Ponsford; A.P. Boon; A. Williams; Elwyn Elias; P. McMaster

17 (33%) of 52 patients who underwent 56 consecutive orthotopic liver transplants had serious neurological complications postoperatively. The commonest complication was fits, which occurred in 13 (25%) patients. 50% of patients had their onset of fits within the first week. In 3 patients the fits were associated with postoperative metabolic encephalopathy and fatal progressive neurological deterioration. In some patients the evidence implicating cyclosporin in the development of fits is strong. In others factors such as electrolyte disturbances, steroid treatment for graft rejection, and cerebral infarction may have contributed to the development of the fits. Phenytoin controlled the fits in 10 out of 13 patients. Other neurological complications included 1 case of central pontine myelinolysis, 1 of cerebral abscess, and 4 of non-encephalopathic psychosis.


The Lancet | 1995

Sex mismatch as a risk factor for chronic rejection of liver allografts

D Candinas; Bridget K. Gunson; P. McMaster; James Neuberger; Peter Nightingale; Stefan G. Hubscher

Chronic irreversible rejection is a major cause of graft loss and retransplantation after orthotopic liver allotransplantation. To identify risk factors we retrospectively analysed 423 adult consecutive primary liver allograft recipients. The endpoint of the study was graft failure due to chronic rejection leading either to retransplantation or death. Chronic rejection developed in 22 (5.2%) patients. Pretransplant diagnosis of primary biliary cirrhosis or autoimmune hepatitis, recipient age less than 30 years, 1 or more episodes of acute cellular rejection, and transplantation of an organ from cytomegalovirus (CMV). IgG positive donor to an IgG negative recipient were identified as risk factors for chronic rejection. Transplantation of a liver from a male donor into a female recipient was also associated with an increased probability of chronic rejection. By logistic regression analysis, the probability of chronic rejection was predicted by: sex and cytomegalovirus match of donor and recipient, the presence of acute rejection, recipient age, transplantation for autoimmune hepatitis or primary biliary cirrhosis, and recipients receiving no azathioprine during the third month after transplantation. Sensitisation to antigens expressed by bile-duct epithelium as in primary biliary cirrhosis or exposure to donor bile-duct minor histocompatibility antigens, such as the male sex related H-Y antigen, may provide an explanation. More selective allocation of donor organs may allow a reduction in the incidence of ductopaenic rejection and graft loss.


Transplant International | 2000

Outcome of liver resection and transplantation for fibrolamellar hepatocellular carcinoma

G. El-Gazzaz; W. Wong; M. K. El-Hadary; Bridget K. Gunson; Darius F. Mirza; A. D. Mayer; John A. C. Buckels; P. McMaster

Abstract Fibrolamellar hepatocellular carcinoma (FL HCC) is an uncommon variant of hepatocellular carcinoma occurring usually in non‐cirrhotic livers. Hepatic resection or transplantation offers the only chance of cure. We reviewed our experience of surgery for FL HCC from 1985‐1998. Twenty patients with FL HCC (13 females and 7 males) median age 27 years (range 12‐69) were treated either by hepatic resection [n = 11; extended right hepatectomy (5), extended left hepatectomy (1), right hemihepatectomy (2), left hemihepatectomy (2), left lateral segmentectomy (1)] or, if the disease was non‐resectable, by transplantation (n = 9). The median follow up was 25 months (1‐63). The prognostic factors analysed included size [less than 5 cm (3 patients), more than 5 cm (17 patients)], number [solitary (16 patients), multiple (4 patients)], capsular invasion (6 patients), vascular invasion (11 patients) and lymph node invasion (6 patients). The overall survival at 1, 3 and 5 years was 89.5, 75 and 50 %, respectively. The liver resection survival was better than liver transplantation survival at 3 years 100 vs 76 %, respectively (P < 0.025). Although all prognostic factors analysed did not show a significant difference, there is tendency that tumour stage was the most significant for prognosis. Most of the patients in this study are young and presented without specific symptoms, with normal liver function range and had no tumour marker to help in diagnosis. As a result most of our patients were diagnosed late. However the outcome of surgical intervention was favourable.


Journal of Pediatric Surgery | 1996

Unresectable hepatic tumors in childhood and the role of liver transplantation

O.A. Achilleos; Laura J Buist; Deirdre A Kelly; Faro Raafat; P. McMaster; A. D. Mayer; John A. C. Buckels

Liver transplantation has been performed in five children with unresectable hepatic tumors who did not have extrahepatic metastases at the time of surgery. Two of the children had hepatoblastomas, one had an infantile hemangioendothelioma, and two had a hepatoma. The two children who had hepatoblastoma are well (37 and 25 months posttransplant) and have no evidence of recurrence. The child with infantile hemangioendothelioma had a successful operation, with good quality of life, but died of tumor recurrence 41 months after transplantation. Both children with hepatomas died, one of graft failure owing to chronic rejection and the other of tumor recurrence 5 months posttransplant. These results suggest that liver transplantation may be successful in children with unresectable hepatic tumors without extrahepatic spread and should be considered particularly for the treatment of hepatoblastoma.


Journal of Pediatric Surgery | 1993

Liver transplantation in babies and children with extrahepatic biliary atresia.

S.V. Beath; G. Pearmain; D.A. Kelly; P. McMaster; A. D. Mayer; John A. C. Buckels

Orthotopic liver transplantation (OLT) is a life-saving procedure for end-stage liver failure. We reviewed 39 children (24 girls, 15 boys) who received OLT for biliary atresia from 1987 to 1991. Twenty had unsuccessful portoenterostomy, 6 were referred too late for a drainage operation, and the remaining 13 achieved bile drainage but developed portal hypertension. At transplant 37 had decompensated liver disease with varices (28), ascites (24), encephalopathy (17), and gastrointestinal bleeding (12). The median weight and age at transplant were 8 kg and 12.6 months, respectively. The median waiting time was 65 days. Forty-eight grafts (30 reduced and 18 whole) were performed; graft loss was 33% and 27%, respectively. Of the 30 segmental grafts, 15 were reduced conserving the left lateral segment and hepatic vein (Brisbane technique)--13 were from the left lobe and 2 from the right lobe. The overall subject survival rate is 72%. Eleven deaths occurred: primary nonfunction (3), sepsis (3), perioperative bleed (3), and other causes (2). Early complications included: hepatic artery thrombosis (5), hepatic vein thrombosis (2), bowel perforation (3), biliary leak (3), and acute rejection (8). Later complications were chronic rejection (4) and biliary stricture requiring reconstruction (3). Follow-up at 12 months confirms good quality of life for both child and family with catch up growth and normal development. Technical advances in reduction hepatectomy have allowed us to treat small babies under 1 year with an urgent requirement for OLT, with comparable results to those obtained with whole grafts. In conclusion, in the future size and age need not be a contraindication to OLT in children with biliary atresia.


Transplantation Proceedings | 1997

Three-year follow-up of the European Multicenter Tacrolimus (FK506) Liver Study

R. Pichlmayr; Michael Winkler; P. Neuhaus; P. McMaster; Roy Calne; G. Otto; Roger Williams; Carl-Gustav Groth; Henri Bismuth

Abstract TACROLIMUS was initially administered to liver transplant recipients as primary immunosuppressive therapy in conjuction with low-dose steroids at the University of Pittsburgh in 1989. Initial results indicated that tacrolimus was associated with significant improvements in patient and graft survival rates when compared with cyclosporine (CyA)-treated historical controls.1,2 Treatment with tacrolimus also resulted in marked reductions in the incidence of rejection and steroid requirements.2 Subsequently, two international, multicenter, prospectively-randomized, parallel-group trials were initiated (one in Europe and one in the United States) to evaluate and compare the efficacy and safety of tacrolimus- and CyA-based therapy. Results at 6,3–9 12,10–15 and 24 months16–18 have been published previously. This report addresses the continued follow-up of the European study with attention now focusing on 3-year data.


Transplant International | 1996

Two‐year data from the European multicentre tacrolimus (F 06) liver study

Roger Williams; Peter Neuhaus; Henri Bismuth; P. McMaster; R. Pichlmayr; Roy Calne; G. Otto; Carl G. Groth

Abstract  To provide a more definitive assessment of the efficacy and safety of tacrolimus therapy in comparison with cyclosporin, the extended follow‐up of the European multicentre study is reported. Two‐year Kaplan‐Meier estimates indicated significant reductions in acute (tacrolimus 45.4 %, cyclosporin 55.8 Yo; P= 0.006), refractory (1.2 % versus 6.4 %; P= 0.003) and chronic rejection (2.0 % versus 6.9 %; P= 0.015) despite significantly lower steroid usage in patients receiving tacrolimus therapy. Patient and graft survival rates (80.6 % versus 74.8 % and 74.5 % versus 70.0 %, respectively) were also superior, although these failed to reach statistical significance. Safety profiles were comparable for most major categories (including renal, neurological and glucose metabolic disorders) and in certain aspects were more favourable for tacrolimus. Hypertension (28.0 % versus 39.6 %, P < 0.01) and cytomegalovirus infection (14.8 % versus 22.3 %, P< 0.01), two events with important long‐term clinical consequences, were reported significantly less frequently. Hirsutism (0.0 % versus 8.7 %, P< 0.01) and gum hyperplasia (0.0 % versus 2.3 Yo, P 0.05) were absent in patients receiving tacrolimus. Tacroli‐mus appears to provide effective and safe long‐term immunosuppres‐sion.

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John A. C. Buckels

Queen Elizabeth Hospital Birmingham

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Darius F. Mirza

Queen Elizabeth Hospital Birmingham

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Jacques Pirenne

Katholieke Universiteit Leuven

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Elwyn Elias

Queen Elizabeth Hospital Birmingham

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A. D. Mayer

Queen Elizabeth Hospital Birmingham

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Roy Calne

University of Cambridge

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J Buckels

University of Birmingham

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