Gauging mixed climate extreme value distributions in tropical cyclone regions.

In tropical cyclone (TC) regions, tide gauge or numerical hindcast records are usually of insufficient length to have sampled sufficient cyclones to enable robust estimates of the climate of TC-induced extreme water level events. Synthetically-generated TC populations provide a means to define a broader set of plausible TC events to better define the probabilities associated with extreme water level events. The challenge is to unify the estimates of extremes from synthetically-generated TC populations with the observed records, which include mainly non-TC extremes resulting from tides and more frequently occurring atmospheric-depression weather and climate events. We find that extreme water level measurements in multiple tide gauge records in TC regions, some which span more than 100 years, exhibit a behaviour consistent with the combining of two populations, TC and non-TC. We develop an equation to model the combination of two populations of extremes in a single continuous mixed climate (MC) extreme value distribution (EVD). We then run statistical simulations to show that long term records including both historical and synthetic events can be better explained using MC than heavy-tailed generalised EVDs. This has implications for estimating extreme water levels when combining synthetic cyclone extreme sea levels with hindcast water levels to provide actionable information for coastal protection.

Projected incremental changes to extreme wind-driven wave heights for the twenty-first century.

Global climate change will alter wind sea and swell waves, modifying the severity, frequency and impact of episodic coastal flooding and morphological change. Global-scale estimates of increases to coastal impacts have been typically attributed to sea level rise and not specifically to changes to waves on their own. This study provides a reduced complexity method for applying projected extreme wave changes to local scale impact studies. We use non-stationary extreme value analysis to distil an incremental change signal in extreme wave heights and associate this with a change in the frequency of events globally. Extreme wave heights are not projected to increase everywhere. We find that the largest increases will typically be experienced at higher latitudes, and that there is high ensemble model agreement on an increase (doubling of events) for the waters south of Australia, the Arabian Sea and the Gulf of Guinea by the end of the twenty-first century.

Improving the Diagnostic Criteria for Primary Liver Graft Nonfunction in Adults Utilizing Standard and Transportable Laboratory Parameters: An Outcome-Based Analysis.

Current diagnostic criteria for primary nonfunction (PNF) of liver grafts are based on clinical experience rather than statistical methods. A retrospective, single-center study was conducted of all adults (n = 1286) who underwent primary liver transplant (LT) 2000-2008 in our center. Laboratory variables during the first post LT week were analyzed. Forty-two patients (3.7%) had 2-week graft failure. Transplant albumin, day-1 aspartate aminotransferase (AST), day-1 lactate, day-3 bilirubin, day-3 international normalized ratio (INR), and day-7 AST were independently associated with PNF on multivariate logistic regression. PNF score =(0.000280*D1AST)+ (0.361*D1 Lactate)+(0.00884*D3 Bilirubin)+(0.940*D3 INR)+(0.00153*D7 AST)-(0.0972*TxAlbumin)-4.5503. Receiver operating curve analysis showed the model area under receiver operating curve (AUROC) of 0.912 (0.889-0.932) was superior to the current United Kingdom (UK) PNF criteria of 0.669 (0.634-0.704, p < 0.0001). When applied to a validation cohort (n = 386, 34.4% patients), the model had AUROC of 0.831 (0.789-0.867) compared to the UK early graft dysfunction criteria of 0.674 (0.624-0.721). The new model performed well after exclusion of patients with marginal grafts and when modified to include variables from the first three post-LT days only (AUROC of 0.818, 0.776-0.856, p = 0.001). This model is superior to the current UK PNF criteria and is based on statistical methods. The model is also applicable to recipients of all types of grafts (marginal and nonmarginal).

Patient perception of skin-cancer prevention and risk after liver transplantation.

INTRODUCTION: Sun exposure is a major risk factor for the development of skin cancer. This is particularly relevant in immunosuppressed liver-transplant recipients (LTRs). Preventative strategies may help minimize the skin-cancer risk in this patient group. METHODS: We assessed 670 patients in our post-transplant clinic, using questionnaires. Patient data were collected, and we assessed whether patients had received education (such as formal talks or information from transplant coordinators or from hepatologists) on skin, sun exposure and skin cancer. In a subset of 280 of the LTRs who responded, we recorded their recall of sun-protection advice and assessed the level of patient adherence to such advice. RESULTS: The response rate was 57.5% (349/607), with a mean responder age of 51.1 years (range 19-84) and an average post-transplant time of 7.1 years (range 0-27). In the recall assessment, 37.2% reported that they were given advice about their skin, while 18.1% were seen by a dermatologist, and education on sun exposure and the risks of skin cancer was given to 65.6% and 47.9%, respectively. Over three-quarters (78%; 185/280) of the patients used mechanical sun protection (i.e. hats/clothing), while 66% reported using sunscreen; 31.8% of these used a sunscreen of the recommended sun protection factor (SPF) of > 30. Twelve patients had developed squamous cell carcinoma after a mean of 10.9 years (1-23) post-transplant; half of these had used either no sunscreen or one with an SPF of < 15. CONCLUSIONS: Despite the fact that LTRs are given information on sun-exposure and SC before and after transplantation, recall of such advice and use of sun-protection methods was only moderate, indicating that regular reinforcement of SC education is needed.

The advent of successful organ transplantation in the Irish HIV positive cohort.

BACKGROUND: Liver disease is an increasing cause of morbidity and mortality in Human immunodeficiency virus (HIV) positive patients. AIM: To describe the first cases of organ transplantation in HIV positive patients in Ireland. METHOD: We report the Irish patients with HIV who received liver transplantation and performed a chart review. RESULT: Two patients received liver transplantation for end stage liver disease caused by Hepatitis C, with survival at 2 years of 100%. CONCLUSION: Liver transplantation is a feasible treatment for patients with HIV and end stage liver disease. The success of transplantation in the HIV positive population should encourage the provision of other medical and surgical interventions previously not offered to patients with HIV.

Manganese-enhanced MRI predicts the histological grade of hepatocellular carcinoma in potential surgical candidates.

AIM: To evaluate the role of manganese-enhanced magnetic resonance (Mn-MRI) in predicting tumour differentiation prior to liver transplant or resection for hepatocellular carcinoma (HCC). MATERIALS AND METHODS: The inclusion criteria were patients with HCC who underwent Mn-MRI prior to transplantation or resection from 2001-2008. T1-weighted MRI images were acquired at 0 and 24h after manganese dipyridoxal diphosphate (MnDPDP) intravenous contrast medium and reviewed prospectively. Manganese retention at 24h was correlated with tumour differentiation and disease-free survival. RESULTS: Eighty-six patients underwent Mn-MRI (transplantation 60, resection 26); 114/125 lesions (91%) that were arterialised as evidenced at computed tomography (CT) and had manganese uptake on MRI were HCC. There were 11 false positives (9%) that were regenerative nodules. Ten of fourteen non-manganese-retaining HCC (71%) were poorly differentiated, compared with only 13/114 manganese-retaining HCC (11%) (p<0.0001). Sensitivity, specificity, positive and negative predictive values of non-retention of MnDPDP in predicting poorly differentiated tumours were 0.43, 0.96, 0.71 and 0.88. Median disease-free survival of patients with non-manganese-retaining HCC was less than for patients with manganese-retaining HCC (14±5 months versus 39±3 months, log rank p=0.025). CONCLUSION: Non-manganese-retaining HCCs are likely to be poorly differentiated and have a poor prognosis. Manganese-enhanced MRI appears to have a role in preoperative assessment of HCC and warrants further evaluation.

Outcomes of severe pregnancy-related liver disease: refining the role of transplantation.

Severe liver disease in pregnancy is generally considered to have a favorable prognosis. The limited data available have not yielded disease-specific prognostic criteria or guidance on who should undergo liver transplantation (LT). We retrospectively evaluated 54 admissions with pregnancy-related liver disease to (1) evaluate if any admission parameters were associated with death and/or transplantation and (2) identify maternal complications. Eighteen had acute fatty liver of pregnancy and 32 had hypertension/eclampsia related disease. Seven patients (13%) died and four (7%) underwent LT. Survival rates were 43/48 if not listed for LT and 4/6 if listed. Of the four transplanted, three survived. Patients who died and/or underwent LT were more likely to have encephalopathy (p = 0.04) and hyperlactaemia (p = 0.03). Serum lactate was the best discriminant (ROC AUC 0.84). An admission lactate greater than 2.8mg/dL had 73% sensitivity and 75% specificity for predicting death or LT. The addition of encephalopathy to this parameter increased sensitivity and specificity to 90% and 86%, respectively. The King's College criteria were not effective in predicting outcome. This study confirms the overall favorable prognosis in pregnancy-related liver failure but indicates that elevated lactate levels in the presence of encephalopathy best identify patients at greatest risk of death or LT.

Phenotypic expression of recurrent disease after liver transplantation.

Recurrence of the primary disease has become a major focus for transplant hepatologists both when investigating graft dysfunction and when tailoring immunosuppression to maximize graft survival. However, disease recurrence varies in penetrance, can be predictable or random, and does not always conform to the expected pattern of disease. The cholestatic hepatitis syndromes associated with hepatitis B and C are the most dramatic examples of phenotypic change. Being on immunosuppressive drugs may intensify the progression of infectious and malignant diseases, but this effect is not predictable. A significant minority of patients with each of the autoimmune diseases, counter-intuitively, get recurrent disease despite immunosuppression of a potency that is adequate to prevent rejection of the liver graft. Disease patterns emerge after liver transplantation for cryptogenic cirrhosis that shed light on the cause of the native liver disease, for example, nonalcohol-related fatty liver disease and autoimmune hepatitis. The phenotypic expression of disease recurrence can be modified by specific drugs used for immunosuppression and by HLA-antigen matching profiles. Understanding and modifying the phenotypic expression of recurrent disease after liver transplantation is a fertile area for research and continued refinement of clinical care.

The prevalence of the activating JAK2 tyrosine kinase mutation in chronic porto-splenomesenteric venous thrombosis.

BACKGROUND: Occult myeloproliferative disorders (MPD) are present in 25% of patients with chronic portal, splenic and mesenteric venous thrombosis (PSMVT). A somatic mutation of JAK2 (JAK2V617F) can be used to identify patients with latent MPD. AIM: We evaluated the prevalence and clinical significance of JAK2V617F in patients with chronic PSMVT. METHODS: Allele-specific polymerase chain reaction was performed to screen for JAK2V617F. RESULTS: Thirty-five patients were tested for JAK2V617F. The underlying pro-coagulant condition was MPD in seven of 35 (20.0%) patients; other aetiologies included hereditary thrombophilia (n = 5), chronic pancreatitis (n = 2), liver abscess (n = 1) and umbilical vein sepsis (n = 3). The remainder were labelled idiopathic, i.e. 17/35 (48.6%) patients. JAK2V617F was detected in 16/35 (45.7%) patients: seven of seven (100%) with MPD, two of 11 (18.1%) with non-MPD acquired conditions and seven of 17 (41.2%) with 'idiopathic' chronic PSMVT. Mean haemoglobin concentration (P = 0.04), haematocrit (P = 0.04), white cell count (P = 0.002) and platelet count (P = 0.05) were significantly higher in patients with JAK2V617F. None of the seven patients with latent MPD have progressed to overt MPD over median follow-up of 85 months. CONCLUSION: JAK2V617F occurs in 41% of patients with idiopathic chronic portal, splenic and mesenteric venous thrombosis, confirming the presence of latent myeloproliferative disorders, and should form part of the routine pro-coagulant screen.

Randomized controlled trial of tacrolimus versus microemulsified cyclosporin (TMC) in liver transplantation: poststudy surveillance to 3 years.

The 1-year results of the tacrolimus versus microemulsified cyclosporin (TMC) study found a benefit with tacrolimus immunosuppression after primary liver transplants in adults with respect to freedom from graft loss and immunological failure. The integrity of the randomization process was preserved for a further 2 years for poststudy surveillance. The data after 3 years confirms the significant difference between tacrolimus and cyclosporin with tacrolimus less likely to meet the composite primary endpoint (log rank p = 0.01; relative risk 0.75; 95% CI 0.60-0.95; p = 0.016). However, freedom from death or retransplantation no longer achieves statistical significance (relative risk 0.79; 95% CI 0.62-1.02; p = 0.065). A total of 62.1% of patients randomized to tacrolimus were alive at 3 years with their original graft and still on their allocated study medication, as compared with only 41.6% in the cyclosporin limb (p < 0.001). No difference was detected between tacrolimus and cyclosporin in hepatitis-C-positive patients with the available data. The TMC study confirms after 3 years of follow-up the benefits of tacrolimus-based immunosuppression over cyclosporin using C(0) monitoring.

Liver transplantation alcohol related liver disease: (deliberately) stirring a hornet's nest!

Outcomes after liver transplantation for alcohol related liver disease compare very favourably with those documented for other causes of cirrhosis. Despite this, 5% or less of patients with advanced alcohol related liver disease are considered for transplantation. The reasons for this are complex but include professional reluctance to refer these patients for formal assessment as well as a limited and dwindling number of organs available for transplantation. Demonstrating abstinence from alcohol consumption remains central to the assessment of candidates for transplantation. Return to alcohol consumption after transplantation can follow a pattern of abuse with consequences for health and survival but may also be controlled and of little clinical significance. A better understanding of the issues influencing these outcomes should decrease the tension that currently exists between patient expectations, professional opinion, and the attitude of the general public who gift organs for donation.

Long-term outcome of immunosuppression withdrawal after liver transplantation.

Eighteen liver transplant recipients were followed up for 10 years after a trial of immunosuppression withdrawal. Three groups were identified according to the early outcome of complete (group A, n = 5), partial (group B, n = 9), and unsuccessful (group C, n = 4) withdrawal of immunosuppression. The indications for liver transplantation (LT) (August 1983-December 1988) were as follows: primary biliary cirrhosis (n = 3), primary sclerosing cholangitis (n = 3), Budd-Chiari syndrome (n = 3), acute liver failure (n = 3), hepatitis C virus (HCV) cirrhosis (n = 1), HCV and autoimmune hepatitis (n = 1), HCV and alcohol-related cirrhosis (n = 1), HCV and hepatocellular carcinoma (HCC) (n = 1), cystic fibrosis (n = 1), and liver metastases from testicular teratoma (n = 1). Immunosuppression was based on cyclosporine. All patients experienced 1 or more complications of prolonged immunosuppression (median, 7 years; range, 5-11). Thirteen patients (72%) are alive at a median interval of 17 years (range, 16-21) after LT. Of the 5 patients in group A, 2 currently have normal graft function with no rejection episodes, and 3 have restarted immunosuppression following late low-grade acute rejection (n = 1), retransplantation for chronic rejection (n = 1), and kidney transplantation (n = 1). Of the 9 patients in group B, 5 died. The deaths were due to ruptured arterial pseudoaneurysm following retransplantation, HCC recurrence, cardiac failure, renal failure, and posttransplant lymphoma at 5, 7, 7, 14, and 17 years after LT, respectively. All 4 patients in group C are alive on a full immunosuppressive regimen. Long-term follow-up of 18 LT recipients withdrawn from immunosuppression has shown that at a median of 17 years 10% of patients remain off all immunosuppression.

Immunosuppression withdrawal after auxiliary liver transplantation for acute liver failure.

BACKGROUND: The potential for immunosuppression withdrawal is the rationale for auxiliary liver transplantation (AUX) in patients with acute liver failure (ALF). PATIENTS AND METHODS: Forty-four AUX were performed in 28 adults and 16 children with ALF secondary to seronegative hepatitis (n = 20; 45%), paracetamol hepatotoxicity (n = 14; 32%), acute viral hepatitis (hepatitis B virus [HBV] n = 3, Epstein-Barr virus n = 1; 9%), drug-induced hepatitis (n = 3; 7%), autoimmune hepatitis (n = 2; 5%), and mushroom poisoning (n = 1; 2%). All patients fulfilled the King's College Hospital transplant criteria for ALF. After partial hepatectomy, 38 patients received a segmental auxiliary graft and six, a whole auxiliary graft. Immunosuppression was based on calcineurin inhibitors and steroids. RESULTS: Thirty-four patients (77%) are alive after a median follow-up of 30 months (range 4 to 124). Eight adults and two children died of sepsis (n = 6; 14%) at a median interval of 30 days (range 2 to 66), intraoperative cardiac failure (n = 1), brain edema on postoperative day 8 (n = 1), sudden death on day 35 (n = 1), and multiple organ failure associated with HBV recurrence 4 years after transplantation (n = 1). Three patients underwent retransplantation for small-for-size graft syndrome with sepsis on postoperative day 15 (n = 1) and for ductopenic rejection 4 and 15 months after AUX (n = 2). In 10/31 (32%) survivors (6/18 adults and 4/13 children) immunosuppression was completely withdrawn after a median of 19 months. CONCLUSION: Complete immunosuppression withdrawal can be achieved in a significant proportion of patients after AUX for ALF.

Acute liver failure.

Acute liver failure is a complex multisystemic illness that evolves quickly after a catastrophic insult to the liver leading to the development of encephalopathy. The underlying aetiology and the pace of progression strongly influence the clinical course. The commonest causes are paracetamol, idiosyncratic drug reactions, hepatitis B, and seronegative hepatitis. The optimal care is multidisciplinary and up to half of the cases receive liver transplants, with survival rates around 75%-90%. Artificial liver support devices remain unproven in efficacy in acute liver failure.

Anti-interleukin 2 receptor antibodies and mycophenolate mofetil for treatment of steroid-resistant rejection in adult liver transplantation.

BACKGROUND: Steroid-resistant rejection (SRR) results in significant morbidity and mortality from the adverse effects of rescue therapy and in graft loss from chronic rejection. In our knowledge, the efficacy and safety of anti-interleukin (IL) 2r antibodies (daclizumab and basiliximab) for the treatment of SRR in adult liver transplantation has not previously been evaluated. METHODS: Twenty-five patients received either daclizumab or basiliximab as rescue therapy for SRR. Outcome and biochemical parameters were recorded before and after treatment with an anti-IL-2r antibody. RESULTS: The median time from transplantation to SRR was 25 days. Secondary immunosuppression included mycophenolate mofetil in 18 patients. Twelve patients (48%) had complete resolution of SRR. Aspartate transaminase levels normalized at a median of 37 days (range, 1-168 days). In 13 patients (52%) progressive hepatic dysfunction developed. Four of these patients received another transplant, and 6 patients had chronic rejection. Three patients died with graft failure. Of 16 patients with acute cellular rejection, 12 (75%) had resolution, 2 had chronic rejection, 1 required a repeat transplantation, and 1 died with graft failure. In contrast, all 9 patients with established chronic rejection in their pretreatment biopsy continued to have significant graft dysfunction, with 4 having persistent chronic graft dysfunction, 3 requiring repeat transplantation, and 2 dying with graft failure. CONCLUSION: Twelve (48%) of 25 patients who received an anti-IL-2r antibody because of SRR were successfully treated. All successfully treated patients had ongoing acute cellular rejection at liver biopsy (75%), whereas patients with histologic evidence of chronic rejection responded poorly.

Tacrolimus versus microemulsified ciclosporin in liver transplantation: the TMC randomised controlled trial.

BACKGROUND: Calcineurin inhibitors are the most commonly used immunosuppressive drugs in liver transplantation, but the optimum initial immunosuppression regimen is not known. The aim of our study was to compare tacrolimus with microemulsified ciclosporin, in a regimen with standardised concomitant immunosuppressive therapy. METHODS: In all liver transplant centres in the UK and Republic of Ireland, 606 patients undergoing a first orthotopic liver transplantation were randomly assigned open-label tacrolimus or microemulsified ciclosporin. Primary outcome was the combined frequency (whichever occurred first) of death, retransplantation, or treatment failure for immunological reasons, analysed by intention to treat. FINDINGS: 96% of patients received the treatment allocated to them. The primary outcome was reached in 62 (21%) of 301 patients in the tacrolimus group versus 99 (32%) of 305 allocated microemulsified ciclosporin (relative risk 0.63 [95% CI 0.48-0.84], p=0.001; time-to-event analysis log-rank test p=0.002): deaths (50 [17%] vs 72 [24%]); retransplantations (11 [4%] vs 31 [10%]) treatment failure for immunological reasons (6 [2%] vs 12 [4%]). The relative risk for the composite outcome was in favour of tacrolimus. The main causes of death in both trial groups were sepsis and multiple organ failure (31 [10%] vs 30 [10%]), and the main cause for retransplantation was hepatic artery thrombosis (6 [2%] vs 17 [6%]). Renal dysfunction and the need for antihypertensive therapy were much the same in both groups. Tacrolimus was more diabetogenic. INTERPRETATION: Clinical outcome at 1 year was better with tacrolimus-based immunosuppression than with microemulsified ciclosporin during the first year after liver transplantation. Tacrolimus should be the first choice of calcineurin inhibitor for patients receiving their first liver graft.

Graft dysfunction mimicking autoimmune hepatitis following liver transplantation in adults.

In children, a type of graft dysfunction associated with autoimmune features has been described. We have identified 7 adult liver-transplant (LT) recipients from a series of over 1,000 consecutive transplant recipients who presented between 0.3 years and 7.2 years following transplantation with characteristic symptoms, autoantibody profiles, and histologic findings of autoimmune disease. The indications for transplantation were Ecstasy overdose, alcohol-related cirrhosis, primary sclerosing cholangitis (PSC) (2), primary biliary cirrhosis (PBC), hepatitis C cirrhosis, and cryptogenic cirrhosis. Two patterns of de novo autoantibody development were noted; anti-liver-kidney-microsome (LKM) antibody development at high titer in association with an aspartate transaminase (AST) > 500 and antinuclear (ANA) and antismooth muscle (AMA) antibody development at titers >1/80 with lower AST levels. All cases had elevated IgG. Liver biopsies showed changes of an autoimmune-type hepatitis with portal and periportal hepatitis in association with a marked infiltrate of plasma cells, lymphocytes, and bridging collapse. Two patients lost their grafts because of the disease. Patients were treated with reintroduction of steroids and azathioprine in cases in which it had been withdrawn. Major histocompatibility class I and II mismatching did not incur risk. Eight of 12 liver allografts were acquired from either DRB*0301- or DRB*0401-positive donors, and 4 recipients were DRB*0301-positive. This series illustrates that both symptoms and histologic findings of graft dysfunction compatible with autoimmune hepatitis (AIH) exist in adult LT recipients. Graft loss may be a consequence. This entity may represent a specific type of rejection that should currently be classified as "graft dysfunction mimicking autoimmune hepatitis."

Randomized trial of lamivudine versus hepatitis B immunoglobulin for long-term prophylaxis of hepatitis B recurrence after liver transplantation.

BACKGROUND/AIMS: The long-term prophylaxis of hepatitis B after liver transplantation requires further optimization. In a randomized trial we investigated a regimen where the initially given hepatitis B immunoglobulin (HBIg) is replaced by long-term lamivudine treatment. METHODS: Twenty-four liver transplant recipients (all HBsAg-positive/HBV DNA-negative before transplantation), who had received HBIg for at least 6 months without HBV recurrence, were randomized to receive lamivudine (n = 12) or HBIg (n = 12) for 52 weeks. The efficacy criteria involved seronegativity for HBsAg and undetectable HBsAg/ HBcAg in the liver. RESULTS: Twenty-one of 24 patients completed the study without hepatitis B virus (HBV) recurrence (11 on HBIg, ten on lamivudine), while three patients became HBsAg-positive. Amongst those without HBV recurrence HBV DNA was detectable only by polymerase chain reaction, intermittently in serum and lymphocytes, and in liver specimens from six of eight patients receiving HBIg and five of seven receiving lamivudine. YMDD variant was found in four cases with no viral antigen expression. Eight patients continued lamivudine after the study and during an additional 6-22 months remained HBsAg-negative with normal graft function. CONCLUSIONS: Substitution of HBIg with lamivudine is effective for prevention of HBV recurrence in low-risk liver transplant recipients and offers a convenient and cost-effective alternative for long-term HBV prophylaxis.