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P J Gow

Publications and source records attributed to P J Gow.

At least 19 recordsLinked to original sources
PubMed2004

Revealing the cause of cryptogenic cirrhosis by posttransplant liver biopsy.

INTRODUCTION: Because of the tendency for preexisting diseases to recur following liver transplantation, studying the course of patients who were transplanted for their cryptogenic cirrhosis may reveal features of the original cause. We examined the clinicopathological posttransplant progression of patients transplanted due to cryptogenic cirrhosis with emphasis on the detection of posttransplant steatosis and steatohepatitis. METHODS: The data on all patients transplanted for cryptogenic cirrhosis and their routine 1-year posttransplant liver biopsies were compared to a control group of a randomized sample of patients transplanted for other indications matched for length of follow-up. The posttransplant histological diagnosis was based on the latest available biopsy. RESULTS: Among 1710 patients, 39 present with cryptogenic etiology survived at least 1 year after transplantation. The control group consisted of 78 patients. The mean ages of the two groups were 50.7 and 49.3 years and the mean follow-up periods 6.2 and 5.7 years, both of which were similar. There was a significantly greater prevalence of posttransplant steatosis and steatohepatitis among the cryptogenic group (37.5 vs 16.7%, P = .048). The difference in patients with at least moderate steatosis was more pronounced (18.8 vs 3.3%, P = .035). Half of these cases progressed to fibrosis and cirrhosis after 48 months. CONCLUSIONS: This study found a greater incidence of allograft steatosis and steatohepatitis among patients transplanted for cryptogenic cirrhosis compared with a control group. A significant proportion of these patients developed a picture resembling nonalcoholic steatohepatitis, which progressed to fibrosis and cirrhosis.

Adult↗
PubMed2002

Advancing donor liver age and rapid fibrosis progression following transplantation for hepatitis C.

BACKGROUND AND AIM: Cirrhosis with liver failure due to hepatitis C virus (HCV) infection is the most common indication for liver transplantation (LT). Reinfection of the transplanted liver by HCV is inevitable, and aggressive hepatitis with accelerated progression to graft cirrhosis may be observed. Of concern, recent reports suggest that the outcome of LT for HCV may have deteriorated in recent years. Determinants of rate of progression to cirrhosis in the immunocompetent non-transplant patient are well defined, and the most powerful determinant is patient age at the time of infection. Following LT for HCV, recipient age does not affect outcome of HCV reinfection. However, the impact of donor age on graft fibrosis progression rate following LT has not been examined. METHODS: We have examined post-transplant biopsies to assess histological activity, including fibrosis stage (scored 0-6 units, 6 representing established cirrhosis), and to calculate fibrosis progression rates in 101 post-transplant specimens from 56 HCV infected LT patients. Univariate and multivariate analyses examined the impact of parameters including recipient and donor age and sex on fibrosis progression rate, and on predicted time to cirrhosis. RESULTS: For the cohort, median fibrosis progression rate was 0.78 units/year, and median interval from transplantation to development of cirrhosis was 7.7 years. In multivariate analysis, donor age (not recipient age) was a powerful determinant (p=0.02) of fibrosis progression rate. When the liver donor was younger than 40 years, median progression rate was 0.6 units/year and interval to cirrhosis was 10 years. When the donor was aged 50 years or more, median progression rate was 2.7 units/year and interval to cirrhosis only 2.2 years. During the observation period there has been a significant increase in donor age (p=0.01) but date of transplantation per se is not a determinant of progression rate when included in multivariate analyses. CONCLUSIONS: Donor age has a major influence on graft outcome following transplantation for HCV. The changing organ donor profile will affect the long term results of LT for HCV. These observations have important implications for donor liver allocation.

Adult↗
PubMed2001

Primary sclerosing cholangitis associated with rheumatoid arthritis and HLA DR4: is the association a marker of patients with progressive liver disease?

In four cases we describe the unique association of primary sclerosing cholangitis (PSC) and rheumatoid arthritis (RA). In three of the cases the liver disease was unusually progressive, proceeding to cirrhosis in 14, 18 and 48 months from diagnosis. The three cases with progressive liver disease and ulcerative colitis were all HLA type DR4. The fourth patient also suffered from coeliac disease in addition to PSC and RA and has remained asymptomatic over 7 years of follow-up. RA in association with PSC may serve as a clinical marker of patients at high risk of progression to cirrhosis who need to be kept under particularly close observation. In addition, PSC needs to be considered in the differential diagnosis of all patients with RA and cholestatic liver function tests. This is especially important given the link between PSC and an increased risk of colonic carcinoma, and thus the need for surveillance colonoscopy.

Adult↗
PubMed2001

Neonatal hepatic drug elimination.

After the transition from in utero to newborn life, the neonate becomes solely reliant upon its own drug clearance processes to metabolise xenobiotics. Whilst most studies of neonatal hepatic drug elimination have focussed upon in vitro expression and activities of drug-metabolising enzymes, the rapid physiological changes in the early neonatal period of life also need to be considered. There are dramatic changes in neonatal liver blood flow and hepatic oxygenation due to the loss of the umbilical blood supply, the increasing portal vein blood flow, and the gradual closure of the ductus venosus shunt during the first week of life. These changes which may well affect the capacity of neonatal hepatic drug metabolism. The hepatic expression of cytochromes P450 1A2, 2C, 2D6, 2E1 and 3A4 develop at different rates in the postnatal period, whilst 3A7 expression diminishes. Hepatic glucuronidation in the human neonate is relatively immature at birth, which contrasts with the considerably more mature neonatal hepatic sulfation activity. Limited in vivo studies show that the human neonate can significantly metabolise xenobiotics but clearance is considerably less compared with the older infant and adult. The neonatal population included in pharmacological studies is highly heterogeneous with respect to age, body weight, ductus venosus closure and disease processes, making it difficult to interpret data arising from human neonatal studies. Studies in the perfused foetal and neonatal sheep liver have demonstrated how the oxidative and conjugative hepatic elimination of drugs by the intact organ is significantly increased during the first week of life, highlighting that future studies will need to consider the profound physiological changes that may influence neonatal hepatic drug elimination shortly after birth.

Animals↗
PubMed2001

Wilson's disease presenting with rapidly progressive visual loss: another neurologic manifestation of Wilson's disease?

Wilson's disease (WD) is a rare autosomal recessive disorder of copper metabolism resulting in copper-induced tissue damage that primarily involves the liver and central nervous system. The neurologic manifestations of WD almost universally involve a derangement of basal ganglia function or psychiatric disturbance. We report the case of a 46-year-old man presenting with end-stage liver disease caused by WD who had associated rapidly progressive optic neuropathy. We also discuss the possible association between the two conditions.

Hepatolenticular Degeneration↗
PubMed2001

De novo hepatitis B infection acquired during liver transplantation.

Although the use of donor organs from patients negative for hepatitis B surface antigen (HBsAg) but positive for hepatitis B core antibody (HBcAb) is well known to have the potential to transmit hepatitis B to the recipient, routine screening of organ donors for HBcAb is not yet implemented in the UK. We investigated whether current organ donor screening for hepatitis B infection is effective in preventing de novo hepatitis B infection after liver transplantation. The database of the liver transplant unit at the Queen Elizabeth Hospital, Birmingham, was searched for all cases of de novo hepatitis B after liver transplantation between January 1982 and July 2000. Four cases were identified from a population of 1354 (0.3%) adult liver transplant recipients. In all cases, the likely source of hepatitis B in the recipient was the donated organ. De novo acquisition of hepatitis B after liver transplantation occurs within the UK. This problem is likely to be resolved by the institution of HBcAb testing in all liver donors. Continuing the current practice in the UK of incomplete donor hepatitis B testing (HBsAg serology only) can no longer be justified. De novo acquired infection has potentially life-threatening implications to the liver recipient and their contacts.

Adult↗
PubMed2001

Modern management of oesophageal varices.

Haemorrhage from oesophageal varices is a life threatening emergency with a mortality rate in the order of 30%-50%. In the last three decades there have been many advances in the treatment and prevention of variceal bleeding. Over recent years the introduction of new pharmaceutical agents that reduce portal pressure, endoscopic variceal ligation, transjugular intrahepatic portosystemic shunt, and the availability of liver transplantation have further increased the therapeutic options available to the physician treating this disorder. This article reviews the literature regarding therapies available in the treatment of haemorrhage from oesophageal varices and provides guidelines to aid the physicians in clinical decision making.

Algorithms↗
PubMed2000

Conjugation of para-nitrophenol by the isolated perfused neonatal sheep liver.

We examined the metabolism of para-nitrophenol (PNP) in the isolated perfused neonatal sheep liver (n = 8, 0.25-11 days) and compared the findings with our previous data from the perfused near-term fetal sheep liver (Ring, J. A., et al. Drug Metab Dispos 1996, 24, 1378). A three-step dosage regimen was used (72, 144, and 288 micromol of PNP). At the end of each dosage phase, PNP had fallen below detectable levels, and 101 +/- 16% of the dose was accounted for as PNP conjugates. Elimination of PNP from perfusate varied with dose. Elimination was first order with the 72-micromol dose; with the 144-micromol dose, elimination was first order in four livers but Michaelis-Menten kinetics in the remaining four. With all the 288-micromol doses, elimination was Michaelis-Menten and gave the following biochemical parameters: K(m) = 255 +/- 138 microM (fetal = 14.7 microM, P < 0.01), V(max) = 515 +/- 285 nmol/min/g liver (fetal = 34.3 nmol/min/g liver, P < 0.01), and intrinsic hepatic clearance = 2.36 +/- 1.21 mL/min/g liver (fetal = 4.74 mL/min/g liver, P > 0. 05). The mean shunt-corrected hepatic extraction ratio of PNP was 0. 82 (range, 0.40-1.0) and strongly correlated with neonatal age (r = 0.90, P < 0.05). We conclude that PNP is highly extracted by the isolated perfused neonatal sheep liver at much higher efficiency than in the near-term fetal sheep, reflecting a maturation of conjugation that progresses further in the early neonatal period.

Animals↗
PubMed2000

Neonatal hepatic propranolol elimination: studies in the isolated perfused neonatal sheep liver.

Using the isolated perfused neonatal sheep liver model, we examined the disposition of propranolol (n = 8, age 0.25-10 days) and compared our findings with our previous study from the perfused near-term fetal sheep liver (Ring JA, et al. 1995. Drug Metab Dispos 23:190-196). Within 45 min of dosage, perfusate propranolol levels had fallen by three orders of magnitude to be less than the limit of detection. Perfusate disappearance curves were monoexponential in six experiments and biexponential in two experiments. The mean shunt-corrected hepatic extraction ratio was 0.92 +/- 0.09, much greater than that seen in the fetal sheep liver (0.26 +/- 0.13, P < 0.0001) but still less than values in the adult sheep (0.97). At the conclusion of the perfusion, 4-hydroxypropranolol was the major metabolite present and 5-hydroxypropranolol and N-desisopropylpropranolol were minor metabolites. We conclude that the isolated perfused neonatal sheep liver is a useful model with which to study the maturation of neonatal hepatic drug oxidation. Our study shows that propranolol is rapidly eliminated by the neonatal liver to form several metabolites at rates far greater than in the fetal liver, but rates of elimination have not yet reached that reported in the adult sheep liver.

Adrenergic beta-Antagonists↗
PubMed2000

Liver transplantation for primary sclerosing cholangitis.

Primary sclerosing cholangitis (PSC) is a chronic cholestatic liver disease of unknown aetiology that is progressive in most symptomatic patients, advancing toward cirrhosis and liver failure. Liver transplantation is the only therapeutic option for patients with end stage liver disease resulting from this disorder. The results of transplantation for PSC are excellent with one-year survival rates of 90-97% and five-year survival rates of 80-85%, but are closely related to pre-transplant Child-Pugh stage. Recurrence of PSC after liver transplantation is common, occurring in up to 20% of patients, but it appears to have little effect on patient survival, as survival of patients with recurrent PSC is similar to that of those without evidence of recurrence. Cholangiocarcinoma is a catastrophic complication of PSC and as yet no reliable screening method exists. The results of liver transplantation for patients with clinically apparent cholangiocarcinoma are extremely poor, however in patients in whom a microscopic tumour is detected in the explanted liver, survival is similar to those transplanted with PSC without cholangiocarcinoma. Activity of inflammatory bowel disease (IBD) appears to be more severe after transplantation, especially in units where steroid immunosuppression is withdrawn early. Colon cancer appears within the first few years after transplantation in approximately 7% of patients with IBD who are transplanted for PSC. Annual colonoscopy in this population seems prudent.

Bile Duct Neoplasms↗
PubMed2000

Simultaneous occurrence of focal nodular hyperplasia and primary sclerosing cholangitis in a young female.

We report the case of a 22-year-old female with primary sclerosing cholangitis who was found, during hepatic imaging, to have a large liver mass. Imaging techniques and histological examination confirmed the mass to be focal nodular hyperplasia. A review of the literature indicates that the simultaneous occurrence of these two hepatic pathologies is unique. The differential diagnosis of hepatic masses in primary sclerosing cholangitis is discussed. Focal nodular hyperplasia needs to be included in the differential diagnosis of hepatic lesions in primary sclerosing cholangitis.

Adult↗
PubMed2000

Diagnosis of Wilson's disease: an experience over three decades.

BACKGROUND: Wilson's disease is a rare but treatable condition that often presents diagnostic dilemmas. These dilemmas have for the most part not been resolved by the identification and cloning of the Wilson's disease gene. AIMS: To report our experience over three decades with patients with Wilson's disease in order to illustrate the diverse patterns of presentation and thereby broaden the approach to diagnosis. METHODS: Clinical and laboratory findings of 30 patients with Wilson's disease were reviewed. RESULTS: Twenty two patients presented with liver manifestations (eight with fulminant hepatic failure and 14 with chronic liver disease), three with neurological disease, and one with haemolysis; four were asymptomatic siblings of patients with Wilson's disease. Seventy per cent were diagnosed within six months of the onset of symptoms, but diagnosis was delayed for up to nine years. Age range at diagnosis was wide (7-58 years) and five patients were over 40. In patients presenting with non-fulminant disease, 18% had neither Kayser-Fleischer rings nor low caeruloplasmin concentrations. Increased liver copper concentrations were found in all but one patient who had undergone six years of penicillamine treatment. In fulminant hepatic failure (n=8) additional features helpful in the diagnosis included evidence of haemolysis, increased urinary copper (range 844-9375 microg/24 h), and a high non-caeruloplasmin copper (range 325-1743 microg/l). CONCLUSIONS: The diagnosis of Wilson's disease still depends primarily on the evaluation of clinical and laboratory evidence of abnormal copper metabolism. No one feature is reliable, but the diagnosis can usually be made provided that it is suspected. Wilson's disease should be considered in patients of any age with obscure hepatic or neurological abnormalities.

Adolescent↗
PubMed1999

Uptake and excretion of sodium taurocholate by the isolated perfused neonatal sheep liver.

We present a model for perfusion of the isolated perfused neonatal sheep liver which allows examination of drug disposition by the intact organ. We studied the disposition of sodium taurocholate (TC) in seven neonatal lambs (ages 2-11 days) and compared the results with earlier data from the perfused fetal sheep liver (Ring, J. A. et al. Biochem. Pharmacol. 1994, 48, 667-674). Measurements of perfusion pressure, oxygen consumption, lactate:pyruvate ratio, bile flow, and liver histology indicated that the preparation was both viable and stable over a 2 h period. [14C]-labeled TC was added to the reservoir by constant infusion (30 micromol/h) and the ductus venosus shunt quantitated by injection of [153Gd]-labeled microspheres. Shunt-corrected hepatic extraction ratio of TC was 0. 56 +/- 0.14 (fetal 0.23 +/- 0.16, p < 0.005) and clearance of TC was 0.92 +/- 0.35 mL/min/g liver (fetal 0.44 +/- 0.23 mL/min/g, p < 0. 01). We conclude that the isolated perfused neonatal sheep liver is a useful experimental model which will facilitate the study of the developmental physiology and pharmacology of the liver. There is considerable maturation of the biliary excretion of TC between the late fetal and early neonatal periods in the lamb.

Aging↗
PubMed1999

Paracetamol overdose in a liver transplantation centre: an 8-year experience.

BACKGROUND: Paracetamol is a readily available, widely used analgesic that can cause serious hepatic injury when taken in overdose. The aims of this study were to assess the frequency of attendance at the Austin and Repatriation Medical Centre for paracetamol overdose, the frequency of referral to the Victorian liver transplant unit after serious overdoses, the morbidity and mortality rates in all patients treated and the appropriateness of treatment. METHODS: A review of the Austin and Repatriation Medical Centre medical records and of the Victorian liver transplant unit database of all patients attending because of paracetamol overdose from 1988-1995 was undertaken. One hundred and fifty-two patients (103 females, 49 males) files were reviewed. RESULTS: One hundred and thirty-one patients presented directly from the community and 21 were referred specifically for consideration for possible transplantation. The most important predictor of liver injury was time between overdose and arrival at hospital (P< 0.01). Thirteen patients developed fulminant hepatic failure, one of whom received a liver transplant; this patient died post-transplantation and was the only death in the series. CONCLUSIONS: We found that serious liver injury following overdose was uncommon, liver transplantation was rarely needed and death was rare. Although inappropriate delay in instituting N-acetylcysteine treatment after admission to hospital or failure to treat still occurred in a number of cases, delay in presentation to hospital was the main predictor of liver damage.

Acetaminophen↗