Bridget K. Gunson

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

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.

Chronic Renal Failure Following Liver Transplantation: A Retrospective Analysis

BACKGROUND Liver transplant recipients are at risk of chronic renal disease, principally as a result of nephrotoxicity of the commonly used immunosuppressive agents cyclosporine and tacrolimus. We have investigated the incidence of chronic renal failure and its risk factors in our transplant population, which was treated predominantly with cyclosporine. METHODS A single-center retrospective study was done of 883 consecutive adult patients receiving a first liver transplant between 1982 and 1996. Potential risk factors for the development of chronic renal failure were recorded, including serial measurements of cyclosporine therapy and renal function. RESULTS Severe chronic renal failure (serum creatinine level >250 microM/L for at least 6 months) developed in 25 patients, representing 4% of patients surviving 1 year or more. Twelve of these patients developed end-stage renal failure and mortality was 44%. The predominant cause of renal failure was cyclosporine nephrotoxicity. Serum creatinine as early as 3 months after surgery was strongly associated with the eventual development of severe chronic renal failure (P=0.001), and this group could be further subdivided into two groups with differing risk factors. The first group had early (<1 year) renal dysfunction, with older age (P=0.03), cytomegalovirus infection (P=0.03), need for perioperative renal replacement therapy (P=0.06), and regrafting (P=0.06) as risk factors for eventual renal failure; the second group had late-onset (>1 year) renal dysfunction, with cyclosporine levels at 1 month after surgery (P=0.007) and daily and cumulative cyclosporine dosage at 5 years (P=0.01 for both) as risk factors. CONCLUSIONS With improved survival of liver transplant recipients, chronic renal failure has become an important cause of morbidity and is associated with a high mortality. Many patients at risk of severe chronic renal failure may be identified at an early stage. Treatment regimens that avoid or prevent cyclosporine-induced nephrotoxicity are urgently required for this population.

Cardiovascular morbidity and mortality after orthotopic liver transplantation

BACKGROUND Hyperlipidemia and hypertension have been reported in liver allograft recipients and contribute to an increased risk of ischemic heart disease (IHD) after orthotopic liver transplantation (OLT). The aims of the study were (1) to determine the prevalence of risk factors for IHD in these patients and (2) to compare the observed incidence of cardiovascular events and related mortality in allograft recipients with a matched population. METHODS One hundred ten consecutive adults (50 male) who attended for review after OLT (median follow-up 3.9 years; range 0.1-17.9) were assessed for cardiovascular risk factors using current blood pressure, diabetic status, and smoking history and measurements of total cholesterol, high-density lipoprotein cholesterol, and triglyceride concentrations. Cardiovascular events and cardiovascular mortality data were collected from the prospective database of all adult liver allograft recipients and compared to matched data from myocardial infarction registries and Office for National Statistics data, respectively. RESULTS Raised serum cholesterol (>5.0 mmol/L) was found in 48 (44%) patients (18 male), and systolic hypertension (>140 mmHg) was found in 69 (63%) patients (27 male). The relative risk of ischemic cardiac events was 3.07 (95% [confidence interval] CI, 1.98-4.53) and the relative risk for cardiovascular deaths was 2.56 (95% CI, 1.52-4.05) in allograft recipients compared to an age-matched population without transplants. CONCLUSIONS Liver allograft recipients have a greater risk of cardiovascular deaths and ischemic events than an age- and sex-matched population. The prevalence of raised cholesterol concentrations in patients after OLT is similar to those in previous reports. Moderate hypertension and hyperlipidemia may be more detrimental in patients after OLT compared to non-transplant patients without these risk factors.

NEUROLOGICAL COMPLICATIONS FOLLOWING LIVER TRANSPLANTATION

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.

Hepatic artery thrombosis following orthotopic liver transplantation: a 10-year experience from a single centre in the United Kingdom.

Hepatic artery thrombosis (HAT) occurs in 3–9% of all liver transplants and acute graft loss is a possible sequelae. We present our experience in the management of HAT over a 10‐year period. Prospectively collected data from April 1994 to April 2004 were analyzed. There were 1,257 liver transplants, 669 males, median age 51 (16–73) years. There were 61 (4.9%) cases of HAT. Early HAT occurred in 21 (1.8%). Thirty six had graft dysfunction, 11 required a regraft, and 14 died. Positive CMV serology in the donor, cold ischemia time, duration of operation, transfusions of more than 6 units of blood, and 15 units of plasma, an aortic conduit for arterial reconstruction, Roux‐en‐Y biliary reconstructions, regrafts and relaparotomy were associated with HAT. At multivariate analysis, type of biliary anastomosis was the only significant factor associated with HAT. Split or reduced liver graft were not risk factors for HAT. Number of hepatic arteries requiring multiple arterial anastomosis was not a risk for HAT. HAT resulted in a reduction in overall survival post liver transplantation. The incidence of HAT was 4.9%; with 1.8% early HAT and HAT impacted on survival. Surgical technique was not an aetiological factor for HAT. In conclusion, while a Roux‐en‐Y biliary reconstruction was an independent risk factor for HAT, cold ischemia and operative times, the use of blood and plasma and the use of aortic conduits in arterial reconstruction were associated with HAT. Regrafts and reoperation were also identified risk factors. Liver Transpl 12:146–151, 2006.

A re‐evaluation of the risk factors for the recurrence of primary sclerosing cholangitis in liver allografts

Previously, we have found that the absence of the colon after liver transplantation (LT) protects the patient from recurrent primary sclerosing cholangitis (rPSC). As our previous observation has not been confirmed in other series, we have reviewed our cohort of patients grafted for primary sclerosing cholangitis (PSC) with greater numbers and longer follow‐up to reassess the rate, consequences, and risk factors for rPSC. We collected data on patients who underwent LT for PSC between January 1986 and April 2006. Data were collected for cytomegalovirus status, inflammatory bowel disease status, time of colectomy, type of colectomy, donor‐recipient gender mismatch, recipient sex, extended donor criteria (EDC), and donor risk index. Accepted criteria were used to diagnose rPSC. Of a total of 230 consecutive adult patients, 61 (27%) underwent colectomy pre‐/peri‐LT, and 54 (23.5%) developed rPSC at a median of 4.6 (range, 0.5–12.9) years post‐LT. A total of 263 deceased donor grafts were used, and 73 were EDC grafts. A diagnosis of rPSC was made in 61 of the 263 grafts (23%). The recurrence‐free patient survival was significantly better (P < 0.05) in patients who underwent pre‐/peri‐LT colectomy and in those with non‐EDC grafts. In conclusion, in this larger cohort of 230 patients and with longer follow‐up of 82.5 (range, 0.0–238.6) months [in comparison with the previous report of 152 recipients with a follow‐up of 52.8 (range, 1–146) months], we have shown that colectomy remains a significant risk factor for rPSC and that colectomy before and during initial LT for PSC confers a protective effect against rPSC in subsequent graft(s). Moreover, we have shown that EDC grafts are also a significant risk factor for rPSC. Liver Transpl 15:330–340, 2009.

Risk factors for recurrence of primary sclerosing cholangitis of liver allograft

Primary sclerosing cholangitis (PSC) is a disease of unknown cause that effects the biliary tree and is closely associated with inflammatory bowel disease. We did a retrospective analysis of the risk factors associated with recurrence of PSC in an allograft after liver transplantation. Recurrence of disease, assessed by liver histology or imaging the biliary tree, occurred in 56 of 152 patients (37%) at a median of 36 months (range 1.4-120 months). Multivariate analysis showed that being male (relative risk 1.2, 95% CI 0.73-2.15) and an intact colon before transplantation (8.7, 1.19-64.48) were associated with recurrence. These observations could help elucidate the pathogenesis of the disease.

Colorectal cancer in patients with inflammatory Bowel disease after liver transplantation for primary sclerosing cholangitis

Background. Patients with primary sclerosing cholangitis (PSC) and inflammatory bowel disease (IBD) may have an increased risk of developing colorectal cancer (CRC) after liver transplantation (LT). We evaluated our patients with PSC after LT to identify risk factors for CRC and its impact on survival. Patients and Methods. A total of 152 patients (108 men, 100 with IBD) with PSC who underwent 173 LTs between 1986 and May 2000 were analyzed in three groups: (1) PSC without IBD (n=52); (2) PSC with colectomy (pre-LT and at LT) (n=17, colectomy pre-LT in 13 and simultaneous colectomy at LT in four); and (3) PSC with IBD and an intact colon (n=83). The following factors were studied: age, gender, liver, and renal biochemistry, international normalized ratio, Child-Pugh stage, operative time, blood use, hospital stay, immunosuppression, risk of CRC, retransplantation rate, and mortality. Results. The incidence of CRC after LT was 5.3% (8/152) compared with 0.6% (7/1,184) in non-PSC cases (P <0.001). All CRCs in the PSC group were in patients with IBD and an intact colon. The cumulative risk of developing CRC in the 83 patients with an intact colon and IBD was 14% and 17% after 5 and 10 years, respectively (PSC non-IBD group 0% risk after 10 years, P <0.06). The multivariate analysis showed three significant variables related to the risk of developing CRC: colonic dysplasia after LT (P <0.0003), duration of colitis more than 10 years (P <0.002), and pancolitis (P <0.004). The cause of death in patients with CRC was cancer related in 75% of cases with a reduced 5-year survival of 55% versus 75% without CRC (not significant). Conclusion. Patients with PSC undergoing LT with a long history of ulcerative colitis and pancolitis have an increased risk of developing CRC with reduced survival. We advocate long-term aggressive colonic surveillance and colectomy in selected high-risk patients with longstanding severe colitis.

Impact of donor age and year of transplantation on graft and patient survival following liver transplantation for hepatitis C virus

Background. Hepatitis C virus (HCV) infection has become the most common indication for liver transplantation (LT). Graft and patient survival are adversely affected by recurrent infection of the graft. Recent publications have described an inferior outcome for recently transplanted HCV patients and have highlighted the impact of advancing donor age on severity of recurrent HCV. The donor age at which a measurable impact on graft and patient outcome can be observed has not clearly been defined. In addition, the impact of donor age on graft and patient survival for non-HCV patients needs to be examined. Methods. We have examined a large European liver transplant database to define the impact of transplantation date and donor age on graft and patient survival for HCV patients (n=4,736) and the impact for a comparison group of transplanted alcoholic liver disease patients (ALD, n=5,406). Results. For the entire cohorts, graft and patient survival of HCV patients was inferior to ALD patients. Since 1987, there has been a steady and ongoing improvement in the outcome of transplanted ALD patients, an improvement not observed for HCV patients. Every year since 1989, there has been an increase in liver donor age. Graft and patient survival for both ALD and HCV cohorts was adversely affected by advancing donor age. Comparison of graft and patient survival for HCV and ALD cohorts was made according to donor age (donor age subgrouped <20, 20–30, 30–40, 40–50, 50–60 and >60 years of age). For donors younger than 40 years of age, HCV and ALD recipient graft and patient survival are not significantly different. For donors older than 40, HCV recipient graft survival is inferior to ALD graft survival, an inferiority that increases for each advancing decade of donor age. For donors older than 50 years, HCV recipient patient survival is inferior to ALD patient survival, an inferiority that increases when the donor age is greater than 60 years. Conclusion. The results of liver transplantation for European HCV patients is inferior to a comparison group of ALD patients, and have not improved during the past 15 years. Liver donor age has increased significantly during that period. Advancing donor age has an adverse influence on graft and patient survival for ALD and HCV patients, but a significantly greater impact is observed for HCV patients when the donor is older than 40 years.

Weight gain and obesity after liver transplantation

Excessive weight gain is common after liver transplantation and frequently leads to obesity. This has been attributed to immunosuppression. The aim of the present study was to assess the extent of weight gain and the risk factors for weight gain after liver transplantation. Height and estimated dry weight were collected prospectively in consecutive adult liver‐transplant patients, transplanted between January 1996 and October 2001. A total of 597 patients (45% female, median age of 50 years; range 16–73) was studied. Eighty‐six percentage was transplanted for chronic liver disease. The median weight gain at 1 and 3 years was 5.1 and 9.5 kg above dry weight pretransplant. By 1 and 3 years, 24% and 31% had become obese (defined as a body mass index (BMI) >30 kg/m2). There was no significant difference in weight gain between the sexes, those who were obese before transplantation or those who received corticosteroids for >3 months. Weight gain was significantly greater (P < 0.05) in patients aged >50 years and those transplanted for chronic liver disease compared with fulminant liver failure. A pretransplant BMI >30 was a strong indicator that the patient would still have a BMI >30 at 3 years. There was no effect of the type of immunosuppression on weight gain. Obesity is common in the liver transplant population, but it seems to be unrelated to any specific immunosuppressive drug. The greatest weight gain occurs after the first 6 months and intervention with dietary advice at this point could be implemented to minimize the long‐term morbidity and mortality risks associated with obesity.