Short-term intensive treatment for donors with hepatic steatosis in living-donor liver transplantation

BACKGROUND: The use of steatotic livers is associated with increased primary nonfunction in liver transplantation. To reduce the risk of liver injury, we applied a short-term combination therapy of diet, exercise and drugs for 11 living-donor liver transplantation (LDLT) candidates with steatosis. METHODS: Subjects were treated with a protein-rich (1000 kcal/day) diet, exercise (600 kcal/day), and bezafibrate (400 mg/day) for 2-8 weeks. RESULTS: The treatment significantly improved macrovesicular steatosis (30+/-4% vs. 12+/-2% [mean +/- SEM], P = 0.0028). Body weight and BMI were significantly reduced (73.7 +/- 3.2 kg vs. 66.9 +/- 2.9 kg, P = 0.0033, 26.4 +/- 0.7 kg/m vs. 24.1 +/- 0.8 kg/m, P = 0.0033). The treatment completely normalized liver function tests and lipid metabolism. Seven treated liver grafts (left lobe) were transplanted to the recipients. We compared transplanted graft function and resected liver function of donors using parameters such as peak total bilirubin, prothrombin time at postoperative day 3, and peak alanine aminotransferase between treated liver (n = 7) and donor liver without hepatic steotosis (n = 37). The transplanted grafts showed good liver functions, and there was no difference between them with respect to functional parameters. The treated donors also showed good liver functions, and no significant differences in functional parameters. CONCLUSIONS: The results of this study indicate that our short-term treatment effectively reduced steatosis and contributed to safer LDLT. Our findings also suggest that even severely steatotic livers can be used for LDLT grafting subsequent to our short-term treatment regimen.     

Resolution of severe graft steatosis following dual-graft living donor liver transplantation.

Although severely steatotic liver grafts are not suitable for transplantation, they have been used when other, more optimal donors were not available, especially for living donor liver transplantation (LDLT) using two liver grafts. Here we present two cases of dual-graft LDLT in which the recipients showed rapid and complete clearing of fat from livers with previously severe steatosis. In the first case, two left lateral segment grafts were used, one of which was 70% steatotic. Preoperative and posttransplant two-week liver-to-spleen computed tomography-value (L/S) ratios were 0.48 and 1.25, respectively. A liver biopsy taken two weeks after transplantation showed that the fatty changes had almost disappeared. The second case used one left lobe and one left lateral segment graft, the latter of which was 80% steatotic. Preoperative and two-week L/S ratio were 0.58 and 1.34, respectively, and a liver biopsy taken two weeks after transplantation showed less than 3% steatosis. The two donors of the severely steatotic liver grafts recovered uneventfully. These findings show that the fat content of the liver grafts was rapidly removed after transplantation. This observation is helpful in understanding the recovery sequences following transplantation of steatotic liver grafts, as well as expanding the acceptability of steatotic liver grafts.     

The hepatic regeneration power of mild steatotic grafts is not impaired in living-donor liver transplantation.

The aim of this study was to assess histologic changes in steatotic grafts, regenerative capacity, and the outcome of steatotic grafts in living-donor liver transplantation (LDLT). Between September 2002 and February 2004, 55 cases of LDLT with a liver biopsy performed on the 10th postoperative day were enrolled. Patients were grouped according to the intraoperative histologic degree of macrovesicular steatosis (MaS) as follows: Group 1, <5% (n = 24); Group 2, 5 to 15% (n = 24); and Group 3, 15 to 30% (n = 7). The intraoperative microscopic findings and the findings on the 10th postoperative day were compared. Immunohistochemistry was performed using antibody of proliferating cell nuclear antigen (PCNA) and Ki-67 to assess the regeneration power of grafts on the 10th postoperative day. The histologic degree of MaS on postoperative day 10 decreased from 5.22 +/- 1.04% (mean +/- standard deviation) to 2.17 +/- 1.90 in Group 2 (P < .001) and from 21.4 +/- 8.02 to 4.43 +/- 2.70 in Group 3 (P = .003). The number of positively stained hepatocytes in 10 high power fields was 48.0 +/- 17.1, 53.8 +/- 14.4, and 51.5 +/- 4.1 in each group by PCNA (P = .681), and 24.0 +/- 14.0, 25.5 +/- 11.8, and 21.6 +/- 6.8 by Ki-67 (P = .825), respectively. No primary graft nonfunction (PNF) or delayed graft function (DGF) occurred. Major complications were comparable among groups. In conclusion, in LDLT, steatosis disappeared immediately after transplantation and hepatic regeneration power was not impaired in grafts with less than 30% of MaS. Furthermore, a mildly steatotic graft did not increase the risk of graft dysfunction or morbidity in LDLT.     

Hepatic steatosis is associated with intrahepatic cholestasis and transient hyperbilirubinemia during regeneration after living donor liver transplantation

A clear understanding of the mechanisms in steatotic livers that trigger cholestasis or hyperbilirubinemia after living donor liver transplantation (LDLT) remains elusive. We hypothesized that microarchitectural disturbance might occur within regenerating steatotic livers without impairment of hepatic proliferative activity. Liver biopsy specimens from 67 LDLT recipients taken at the 10th postoperative day were scored for the numbers of portal tracts per area (nPT/A) of liver tissue and for intrahepatic cholestasis, and immunostained by proliferating cell nuclear antigen (PCNA) and Ki-67. The preoperative degree of macrovesicular steatosis (MaS) was independently associated with cholestasis after LDLT (P < 0.001). Serum total bilirubin results on the 1st, 3rd, and 7th days post-LDLT in MaS+ (5-30% of MaS; n = 37) patients were significantly higher than those in MaS- (<5% of MaS; n = 30) patients (P = 0.030, 0.042, and 0.019, respectively). Mean numbers of positively stained hepatocytes were 53.1 +/- 12.0 in patients with MaS and 48.0 +/- 17.1 in those without MaS by PCNA (P = 0.390), and 24.4 +/- 10.5 and 24.0 +/- 14.0 by Ki-67 (P = 0.940). However, a significant negative correlation was found between the degree of MaS and nPT/A (P = 0.013), and nPT/A was correlated with the grade of histological cholestasis (r = 0.350, P = 0.039). Intrahepatic cholestasis and hyperbilirubinemia after LDLT could be caused by scanty morphologic change of portal tract during steatotic liver regeneration.     

Using elderly donors in liver transplantation

AIM: Elderly donors are half of the grafts available in our center for liver transplantation. We retrospectively investigated their characteristics, outcomes, and variables related to graft failure. MATERIAL AND METHODS: From 1996 to 2003, 540 (46.4%) of 1163 donors were older than 60 years of age and 236 grafts (43.4%) were transplanted, whereas the others were refused. The clinical investigated variables were examined among this cohort. RESULTS: The median age of donors increased from 37 to 62 years. Donors older than 60 years of age were more often refused than younger ones (66% vs 44%); HCV-positive (9.9% vs 5.4%); HbcAb-positive (18.6% vs 12.6%), and steatotic (35.7% vs 13.9%; P < .01). Among donors older than 60 years, the main parameter to refuse the graft was the grade of steatosis. The variables related to the graft loss from donors older than 60 years were as follows: model for end stage liver disease (MELD) recipient >15 (65% vs 39%), cold ischemia time >10 hours (25% vs 13%), high blood losses (3987 +/- 4764 vs 2664 +/- 2043 mL), and year of liver transplantation after 2000 (26% vs 46%; P < .01). The 1-, 3-, and 5-year graft survival rates were significantly lower among donors older than 60 years than other donors: 75%, 65%, and 62% versus 85%, 83%, and 78%, respectively (P < .001). CONCLUSION: Donors older than 60 years of age provided liver transplants to half of our recipients. The graft survival rate of these organs was lower than that of younger donors and to improve it the other risk variables for poor outcome should be reduced, including MELD score of the recipient and prolonged cold ischemia time.     

Surgery-related morbidity in living donors of right-lobe liver graft: lessons from the first 200 cases

BACKGROUND: Living-donor liver transplantation (LDLT) using the left lateral segment or left-lobe graft has been widely accepted, but currently, right-lobe grafts are more commonly used in many LDLT programs with yet unknown risks for donors. METHODS: We investigated our initial 200 donors of righ-lobe grafts to focus on the incidence and variety of surgery-related morbidity. Changes in liver function tests were also analyzed to clarify the relation with donor age, steatosis of the liver, and residual liver volume (RLV). Complications were surveyed for a median period of 28.7 months. RESULTS: In all the donors, liver enzymes and bilirubin were normalized within 1 month. Enzymes on day 1 were significantly higher in donors with older age, macrovesicular steatosis, and larger RLV. Bilirubin on day 1 was significantly higher in donors with smaller RLV. Biliary enzyme was not normalized in the majority at 1 month after donation. Seventy-five complications occurred in 69 donors. Biliary complications were most common, which consisted of 26 bile leakages (13%) and 3 biliary strictures (1.5%) in 27 donors. No significant dependence of the incidence was observed either for donor age (>or=50 years), body mass index (BMI) (>or=25 kg/m2), estimated RLV (<40%), or medical history. None of the complications led either to mortality or to long-term sequelae. CONCLUSIONS: Complications occurred in a significant proportion of right-lobe donors irrespective of donor age, BMI, estimated RLV, and medical history. Living-liver donor surgery requires more care in right-lobe transplants.     

Clinical experience gained from the use of 120 steatotic donor livers for orthotopic liver transplantation

Steatosis of the donor liver is known to impact on patient and allograft outcome after orthotopic liver transplantation (OLT). The aim of this study is to evaluate the effect of increasing grades of cadaveric donor liver steatosis on recipient outcome. Between January, 1986 and December, 2000, 120 OLTs were performed with 72 mild, 25 moderate, and 23 severe steatotic donor livers. Donors of steatotic livers were more likely to be older (P = .001) and have died of intracerebral haemorrhage than donors of nonsteatotic livers. Initial poor graft function (IPF) was more common in donor livers with either moderate or severe steatosis than in donor livers with mild steatosis (P = .03). Primary graft nonfunction (PNF) occurred in only 1 donor liver with severe steatosis. PGE1 (PGE1) usage was higher in recipients of donor livers with moderate or severe steatosis versus donor livers with mild steatosis (P = .001). Allograft loss was greater at 1 year both in the moderate and severe (P = .03) steatotic liver groups. Patient survival at 3 months and overall allograft survival both were impacted negatively by increasing grades of donor liver steatosis (P = .02, P = .03). Three-month allograft survival was reduced in the steatotic donor livers if the donor was 50+ years old (P = .033). Recipient status at OLT (P = .001) and donor steatosis (P = .046) impacted on 30 day allograft survival (multivariate analysis). In conclusion, increasing grades of donor liver steatosis were associated with worse IPF and increased PGE1 usage. There was a negative impact of steatosis on both recipient and early allograft survival.(Liver Transpl 2003;9:500-505.)     

Steatotic liver transplantation in the mouse: a model of primary nonfunction

BACKGROUND: The number of potential donor organs deemed suboptimal for transplantation because of hepatic steatosis is rising as the obesity rate increases. However, no mouse transplant model has been described within the framework of hepatic steatosis. We describe the development of and our initial experience with a steatotic mouse orthotopic liver transplant model using the ob/ob mouse. This model is technically achievable and functionally mimics primary nonfunction. MATERIALS AND METHODS: Adapting techniques of a nonarterialized murine transplant model, C57BL6 ob/ob mice aged 5-7 weeks (26-35 g) and lean controls served as liver donors and recipients. Orthotopic liver transplantation (OLT) was performed using a two-cuff technique at the infrahepatic cava and portal vein. The suprahepatic cava was anastomosed end to end, and the bile duct was stented. The hepatic artery was not reconstructed. RESULTS: Lean-to-lean OLT was performed with 70% (n = 10) long-term survival. ob/ob-to-age-matched lean recipients had 0% (n = 10) survival because of size discrepancy. ob/ob livers were transplanted to size-matched lean recipients (>3 months old) with short-term survival of 30% (n = 10). These mice survived the operation, awakened, but expired within 24 h. Serum transaminases revealed a significantly higher injury profile in the recipients of the steatotic livers, and histology showed massive centrilobular coagulative necrosis with hemorrhage, the overall picture being that of primary nonfunction. CONCLUSIONS: This novel use of the ob/ob mouse for OLT provides us with a model for steatotic transplantation with primary nonfunction as the end point and may help to better understand the response of the steatotic liver to the insult of transplantation.     

Beneficial effect of pentoxifylline on microvesicular steatotic livers submitted to a prolonged cold ischemia

BACKGROUND: The deleterious effect of steatosis on transplanted livers is mainly related to a microcirculation impairment. We investigated the effect of preservation duration on the recovery of isolated perfused rat steatotic livers and tested the effect of pentoxifylline (PTX), known to have a beneficial effect on hepatic microcirculation. MATERIALS AND METHODS: Fatty rat livers were obtained using a diet able to induce an 80% to 100% microvesicular steatosis within 7 days. We studied the effect of the duration of preservation (12 hr, 18 hr, and 24 hr) on fatty and normal isolated perfused rat liver. PTX was added to University of Wisconsin solution during cold storage (30 mM/kg of weight) and at reperfusion (3 mM) (n=5 livers in each group). Lactate dehydrogenase, aspartate aminotransferase, alanine aminotransferase, bile production, and vascular resistance were evaluated. The liver injury at the end of perfusion was assessed by optical and electron microscopy. RESULTS: For a 24-hr preservation period, fatty livers demonstrated increased enzymatic release (aspartate aminotransferase: 42+/-16 vs. 17+/-5 IU/L/g of liver, P<0.005; alanine aminotransferase: 32+/-13 vs. 13+/-3 IU/L/g of liver, P<0.005; lactate dehydrogenase: 1,207+/-497 vs. 291+/-195 IU/L/g of liver, P<0.001). Vascular resistance (0.32 vs. 0.15 cm H(2)O/min/mL, P<0.0005) and bile output (67+/-24 vs. 141+/-61 mg/g of liver, P<0.05) were decreased. Peliosis appeared after an 18-hr preservation period for fatty livers compared with a 24-hr preservation period for controls. All these negative effects were suppressed by PTX. CONCLUSION: Diffuse microvesicular steatosis became deleterious only after long preservation times (24 hr). PTX prevented this effect.     

Expansion of hepatic progenitor cell in fatty liver graft after living donor liver transplantation

Although it is known that steatotic livers have a reduced ability to regenerate, most individuals with steatosis show generally benign prognosis. We hypothesized that a proliferative blockade in steatotic hepatocytes results in the compensatory expansion of hepatic progenitor cells (HPC) during fatty liver regeneration. Fifty‐four cases of living donor liver transplantation (LDLT) with a liver biopsy performed at the postoperative 10th day were examined. HPC were counted by immunofluorescence histochemical dual‐staining technique using cytokeratin 7 and Ki‐67, and the replicative arrest of hepatocytes was assessed by p21 immunohistochemistry. The degree of ductular proliferation during regeneration 10 days after LDLT correlated both with the degree of steatosis and the number of HPC (P < 0.001). There was no difference in the average number of HPC and the replicative arrest index between donors with or without steatosis before LDLT (P = 0.111 and P = 0.062). However, degree of steatosis correlated with both the expansion of HPC and the replicative arrest index during liver regeneration 10 days after LDLT (P < 0.001 and P < 0.001, respectively). Moreover, increased replicative arrest was strongly associated with HPC expansion (P < 0.001). In conclusion, the compensatory expansion of HPC as a result of impaired hepatocyte replication occurred during steatotic liver regeneration after LDLT.     

Impact of polysol, a newly developed preservation solution, on cold storage of steatotic rat livers.

Chronic shortage of donor organs has led to acceptance of steatotic livers as grafts, although there is a higher risk of primary graft dysfunction. We herein report the beneficial impact of Polysol, a newly developed preservation solution, on cold storage of steatotic rat livers. Dietary hepatic steatosis was induced in Wistar rats by 2-day fasting and subsequent 3-day re-feeding with a fat-free, carbohydrate-rich diet. Fatty livers were retrieved, flushed and then stored at 4 degrees C for 24 hours with either HTK or Polysol. Functional integrity of the grafts was evaluated by isolated reperfusion with oxygenated Krebs-Henseleit buffer at 37 degrees C for 45 minutes in both groups. Polysol preservation resulted in significant reductions of not only parenchymal (AST (IU/L); 6728+/-824 in HTK vs. 3107+/-718 in Polysol; P < 0.001) but also mitochondrial (GLDH (IU/L); 3189+/-773 vs. 1282+/-365; P < 0.01) enzyme release throughout reperfusion. Moreover, PVP (16.9+/-2.7 vs. 7.8+/-1.5 mmHg; P < 0.05), hepatic O2 consumption (0.291+/-0.047 vs. 1.056+/-0.053 micromol/g liver/min; P < 0.001), tissue ATP content (0.695+/-0.086 vs. 1.340+/-0.157 micromol/g dry-liver; P < 0.005), bile production (0.79+/-0.11 vs. 4.08+/-0.66 microL/g liver/45-min; P < 0.001), malondialdehyde into the perfusate (1.922+/-0.198 vs. 0.573+/-0.094 nmol/L; P < 0.0001) and wet/dry-weight ratio of the liver tissues (5.20+/-0.31 vs. 3.85+/-0.15; P < 0.005) were all better preserved by Polysol. In line with these benefits, electron microscopy revealed that Polysol preservation substantially suppressed deleterious mitochondrial alterations in steatotic livers. In conclusion, cold storage using Polysol resulted in significantly better integrity and function of steatotic livers. Polysol, therefore, may be a new alternative especially for "marginal" organs.     

Micro- and macrovesicular steatotic liver model for transplantation induced by ethanol and protein-deficient diet

Steatotic liver grafts are associated with a high incidence of primary nonfunction and initial poor function. Due to the increasing number of liver transplant candidates, centers are inclined to accept marginal donors more frequently. For a lack of a reliable fatty liver model, preservation concepts for fatty livers have hardly been evaluated. Moreover, there is an ongoing debate on the relevance and impact of micro- versus macrovesicular steatotic organs. We therefore intended to establish a steatotic liver model in pigs comprising both micro- and macrovesicular steatotic livers. Five groups of pigs received daily 1 to 6 g ethanol/kg body weight and/or a protein-deficient diet for up to 72 days. Liver biopsy was carried out at days 24, 48, and 72. With an increasing amount and duration of ethanol intake, higher levels of microvesicular steatosis were induced. Ethanol and protein deficient diet resulted in more than 60% microvesicular steatosis after 72 days. Exclusively protein-deficient diet without ethanol induced macrovesicular steatosis of more than 70% after 72 days. For the first time, we established a porcine model of hepatic steatosis that comprises both histologic types of fatty liver: micro- and macrovesicular steatosis induced by ethanol and a protein-deficient diet. We would like to conclude that our model is particularly qualified to study new concepts of preservation for steatotic livers to improve on the posttransplant outcome.     

Use of steatotic graft in living-donor liver transplantation

BACKGROUND: The degree of fatty infiltration in hepatic grafts is known to be an important risk factor for primary graft nonfunction in cadaveric liver transplantation. However, the effect of hepatic steatosis in living-donor liver transplantation (LDLT) has not yet been well defined. In this study, we evaluated the impact that the degree of hepatic graft steatosis has on the outcome of LDLT. METHODS: Sixty consecutive donors and recipients who underwent LDLT between October 1996 and August 2001 at Kyushu University Hospital were the subjects of this study. The pathologic findings of the prereperfusion biopsy of the graft were classified into the following three groups according to the degree of macrovesicular steatosis: None (n=23), 0% steatosis; Mild (n=23), 0% to 20% steatosis; and Moderate (n=6), 20% to 50% steatosis. Liver function tests including total bilirubin (at postoperative day [POD] 7), the peak alanine aminotransferase (ALT) and prothrombin time (at POD 3), and both patient and graft survival were compared among the groups. Furthermore, we also compared the donor parameters including the peak ALT and total bilirubin (at POD 3) and the operative time, blood loss, and length of hospital stay after surgery. RESULTS: The 1-year patient and graft survival were comparable among the groups. The peak ALT was significantly higher in the Moderate group (606+/-641 IU/L) than in the None (290+/-190 IU/L) and Mild (376+/-296 IU/L) groups. Total bilirubin (POD 7) and prothrombin time (POD 3) were comparable among the groups. The donor parameters were comparable among the groups except for the fact that the donor body weight of the Mild and Moderate groups were significantly heavier (P<0.0001) than that of the None group. CONCLUSIONS: In conclusion, the use of a fatty liver graft up to the moderate level can be justified in LDLT, even though ischemia-reperfusion injury tends to be severe in such grafts.     

Use of severely steatotic grafts in liver transplantation: a matched case-control study

BACKGROUND: Although there is a worldwide need to expand the pool of available liver grafts, cadaveric livers with severe steatosis (>60%) are discarded for orthotopic liver transplantation (OLT) by most centers. METHODS: We analyzed patients receiving liver grafts with severe steatosis between January 2002 and September 2006. These patients were matched 1:2 with control patients without severe steatosis according to status the waiting list, recipient age, recipient body mass index (BMI), and model for end-stage liver disease (MELD) score. Primary end points were the incidence of primary graft nonfunction (PNF), and graft and patient survival. Secondary end points included primary graft dysfunction (PDF), the incidence of postoperative complications, and histologic assessment of steatosis in follow-up biopsies. We also conducted a survey on the use of grafts with severe steatosis among leading European liver transplant centers. RESULTS: During the study period, 62 patients dropped out of the waiting list and 45 of them died due to progression of disease. Of 118 patients who received transplants 20 (17%) received a graft with severe steatosis during this period. The median degree of total liver steatosis was 90% (R = 65%-100%) for the steatotic group. The steatotic (n = 20) and matched control group (n = 40) were comparable in terms of recipient age, BMI, MELD score, and cold ischemia time. The steatotic group had a significantly higher rate of PDF and/or renal failure. Although the median intensive care unit (ICU) and hospital stay were not significantly different between both groups, the proportion of patients with long-term ICU (> or =21 days) and hospital (> or =40 days) stay was significantly higher for patients with a severely steatotic graft. Sixty-day mortality (5% vs. 5%) and 3-year patient survival rate (83% vs. 84%) were comparable between the control and severe steatosis group. Postoperative histologic assessment demonstrated that the median total amount of liver steatosis decreased significantly (median: 90% to 15%, P < 0.001). Our survey showed that all but one of the European centers currently reject liver grafts with severe steatosis for any recipient. CONCLUSION: Due to the urgent need of liver grafts, severely steatotic grafts should be no longer discarded for OLT. Maximal effort must be spent when dealing with these high-risk organs but the use of severely steatotic grafts may save the lives of many patients who would die on the waiting list.     

Normal hepatic hemodynamics during early postoperative period in recipients with adult live donor liver transplantation

To recognize "normal" hepatic hemodynamics after live donor liver transplantation (LDLT), we analyzed Doppler parameters on recipients with a right liver graft and donors after extended left hepatectomy. Theoretically these values should be the same. From April 2000 to October 2004, 20 LDLTs were performed using a right liver graft. The 10 recipients without postoperative complications and their donors were included in this study. Portal venous velocity (PVV; cm/s), hepatic arterial peak systolic velocity (cm/s), and hepatic venous peak velocity (HVPV; cm/s) were measured during the first 2 weeks. In donors PVV and HVPV after LDLT were significantly higher after than before left hepatectomy: 19.2 +/- 4.2 vs. 31.5 +/- 13.0 cm/s (P = .013) and 23.0 +/- 7.2 vs. 41.8 +/- 10.3 cm/s respectively (P = .010). However, there were mild degrees of increased PVV and HVPV. In recipients, a markedly increased PVV (106.3 +/- 45.2 cm/s on day 1) was significantly higher than that in donors on each postoperative day. The hepatic arterial resistive index in recipients was also significantly higher than that in donors on each postoperative day, for example, 0.72 +/- 0.11 vs 0.62 +/- 0.04 on day 1 (P = .0326). In conclusion, we have shown "abnormal" hepatic hemodynamics in even those recipients without complications during the early postoperative period after LDLT.     

Significant role of middle hepatic vein in remnant liver regeneration of right-lobe living donors

For adult patients with end-stage liver disease, living-donor liver transplantation (LDLT) of right-lobe grafts with or without the middle hepatic vein (MHV) has been increasingly used in recent years. We investigated the role of the MHV in donor remnant liver regeneration after right-lobe LDLT, which has not been described in previous studies. A total of eight living donors were included in this study of right-lobe LDLT. Four donors underwent right lobectomy (without MHV), and the remaining four underwent extended right lobectomy (with MHV). Regeneration of the donor remnant liver was assessed by volumetric computed tomography studies before and 90 days after LDLT. Comparison between the right-lobe and extended right-lobe donors did not show a clear-cut difference in the net increase of remnant liver volume at 3 months. However, the mean volume increase of the medial segment at the 90th postoperative day was 7% in the extended right-lobe donors and 61% in the right-lobe donors, showing a lower value in the remnant livers without MHV. The MHV plays a specific role in remnant liver regeneration of right-lobe living donors. We expect that this knowledge will contribute to securing a margin of safety in right-lobe LDLT.     

Assignment of steatotic livers by the Mayo model for end-stage liver disease

Prognosis after liver transplantation depends on a combination of recipient and donor variables. The purpose of this study is to define an allocation system of steatotic donor livers relative to recipient model for end-stage liver disease (MELD) score. We reviewed 500 consecutive OLT, computing the MELD score for each recipient. Fatty infiltration in grafts was categorized in no steatosis, 10-30%, 30-60% and > or = 60% steatosis. MELD score did not affect preservation injury and graft dysfunction, which were increased with fat content. Recipient and graft survivals lowered when increasing MELD score. Outcome in low-risk recipients (MELD < or = 9) was not altered with steatosis, except those with > or = 60%. Survival functions in moderate-risk recipients (MELD 10-19) were moderately affected with 10-30% steatosis and severely with those with >30. Exactly 30-60% steatotic grafts work poorly in high-risk recipients (MELD > or = 20), and very poorly with > or = 60% steatosis. Prognosis of candidates is optimally influenced when divergence of recipient-donor risks is presented.     

中度脂肪变性供肝肝移植的早期疗效与安全性研究

目的研究总结浙江大学医学院附属第一医院肝移植中心在脂肪变性供肝肝移植方面的经验并对其临床价值进行评估。方法分析2003年5月至2005年6月采用中度脂肪变性供肝（大泡性脂肪变性肝细胞占30％-60％）的24例成人肝移植受者（观察组）相关临床和随访数据,根据年龄、性别、终末期肝病模型评分和冷缺血时间进行匹配后,将24例采用无或轻度脂肪变性（大泡性脂肪变性肝细胞〈30％）供肝的肝移植受者作为对照组,将两组受者资料和移植肝相关数据进行分析比较。结果移植后1周内两组间肝肾功能变化差异无统计学意义（P〉0．05）,两组间早期移植物功能不全和早期急性肾损伤的发生率以及术后3个月、6个月及1年受者存活率差异均无统计学意义（均P〉0．05）。结论中度脂肪变性供肝在移植后早期可以发挥足够的功能,在排除其他危险因素的前提下可以安全地作为供肝系统的一部分。     

Donor BMI >30 Is Not a Contraindication for Live Liver Donation

The increased prevalence of obesity worldwide threatens the pool of living liver donors. Although the negative effects of graft steatosis on liver donation and transplantation are well known, the impact of obesity in the absence of hepatic steatosis on outcome of living donor liver transplantation (LDLT) is unknown. Consequently, we compared the outcome of LDLT using donors with BMI <30 versus donors with BMI ≥30. Between April 2000 and May 2014, 105 patients received a right‐lobe liver graft from donors with BMI ≥30, whereas 364 recipients were transplanted with grafts from donors with BMI <30. Liver steatosis >10% was excluded in all donors with BMI >30 by imaging and liver biopsies. None of the donors had any other comorbidity. Donors with BMI <30 versus ≥30 had similar postoperative complication rates (Dindo‐Clavien ≥3b: 2% vs. 3%; p = 0.71) and lengths of hospital stay (6 vs. 6 days; p = 0.13). Recipient graft function, assessed by posttransplant peak serum bilirubin and international normalized ratio was identical. Furthermore, no difference was observed in recipient complication rates (Dindo‐Clavien ≥3b: 25% vs. 20%; p = 0.3) or lengths of hospital stay between groups. We concluded that donors with BMI ≥30, in the absence of graft steatosis, are not contraindicated for LDLT.     

Contribution of marginal donors to liver transplantation for hepatitis C virus infection

The use of marginal liver donors can affect the outcomes of liver transplantation in patients with hepatitis C virus (HCV) infection. There are no firm conclusions about which donor criteria are important for allocation of high-risk grafts to recipients with HCV cirrhosis. We performed 120 consecutive liver transplantations for HCV infection between 1995 and 2005. Marginal donor criteria were considered to be: age >70 years, macrovesicular steatosis >30%, moderate-to-severe liver preservation injury, high inotropic drug dose (dopamine >15 microg/kg/min; epinephrine, norepinephrine, or dobutamine at any doses), peak serum sodium >155 mEq/L, any hypotensive episode <60 mm Hg and >1 hour, cold ischemia time >12 hours, ICU hospitalization >4 days, bilirubin >2 mg/dL, AST and/or ALT >200 UI/dL. Graft survival with donors showing these marginal criteria was compared with optimal donors using Kaplan-Meier analysis and the log-rank test. Independent predictors of survival were computed with the Cox proportional hazards model. Fifty-six grafts (46%) were lost during follow-up irrespective of the Model for End-Stage Liver Disease (MELD) scores of the recipients in each category. Upon univariate analysis, grafts with moderate-to-severe steatosis (P = .012), those with severe liver preservation injury (P = .007) and prolonged cold ischemia time (P = .0001) showed a dismal prognosis at 1, 3, and 5 years. Upon multivariate analysis, fat content (P = .0076; OR = 4.2) and cold ischemia time >12 hours (P = .034; OR = 7.001) were independent predictors of graft survival. Among HCV recipients, marginal liver donors worked similar to those from "good" donors, except for those with fatty livers >30%, especially when combined with a prolonged cold ischemia time.