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Recurrent disease following liver transplantation for nonalcoholic steatohepatitis cirrhosis
Article first published online: 24 NOV 2009
Copyright © 2009 American Association for the Study of Liver Diseases
Volume 15, Issue 12, pages 1843–1851, December 2009
How to Cite
Malik, S. M., deVera, M. E., Fontes, P., Shaikh, O., Sasatomi, E. and Ahmad, J. (2009), Recurrent disease following liver transplantation for nonalcoholic steatohepatitis cirrhosis. Liver Transpl, 15: 1843–1851. doi: 10.1002/lt.21943
- Issue published online: 24 NOV 2009
- Article first published online: 24 NOV 2009
- Manuscript Accepted: 17 AUG 2009
- Manuscript Received: 7 JUN 2009
Recurrence of the original disease following liver transplantation is not uncommon and can lead to graft failure. There are limited data on recurrent fatty liver disease following liver transplantation. The aim of this study was to determine the incidence of recurrent fatty liver disease in patients with biopsy-proven nonalcoholic steatohepatitis, its effect on survival, and whether there are any predictive factors for recurrence. We analyzed patients undergoing liver transplantation for nonalcoholic steatohepatitis cirrhosis from 1997 to 2008 at a single center. Patients undergoing transplantation for cholestatic disease, alcohol, hepatitis C, or cryptogenic cirrhosis were controls. Ninety-eight patients underwent transplantation for nonalcoholic steatohepatitis cirrhosis. Recurrent fatty liver disease was seen in 70%, 25% had recurrent nonalcoholic steatohepatitis, and 18% had stage II/IV or greater fibrosis at a mean of 18 months. No patients with recurrent nonalcoholic steatohepatitis developed graft failure or required retransplantation at a follow-up of 3 years. No recipient or donor factors were associated with disease recurrence, although patients with recurrent nonalcoholic steatohepatitis had a higher incidence of diabetes, weight gain, and dyslipidemia at the time of diagnosis of recurrence. One-third of patients with recurrent nonalcoholic steatohepatitis had normal liver enzymes at the time of diagnosis post-transplantation. In conclusion, recurrent fatty liver disease is common following liver transplantation for nonalcoholic steatohepatitis cirrhosis but does not lead to early allograft failure. Recurrent nonalcoholic steatohepatitis can occur despite normal liver enzymes, and features of metabolic syndrome are associated with disease recurrence. Liver Transpl 15:1843–1851, 2009. © 2009 AASLD.
Nonalcoholic fatty liver disease (NAFLD) has become the most common cause of chronic liver disease in the developing world, affecting nearly 1 in every 3 individuals.1–3 Nonalcoholic steatohepatitis (NASH) is considered the progressive form of NAFLD and can eventually lead to cirrhosis and end-stage liver disease.
Recurrent disease post–liver transplantation (LT) is an important problem. Depending on the etiology, recurrent disease can be a common cause of allograft loss. For instance, recurrent hepatitis C virus (HCV) infection after LT is universal and can lead to advanced fibrosis and cirrhosis in 41% of patients within 6 to 10 years, with graft failure accounting for up to 45% of deaths.4
The first reported case of recurrent fatty liver disease was documented in 1992,5 and since that time, there have been several case reports and studies examining the recurrence of NASH post-LT.6–14 However, NASH is a pathological diagnosis, and most of these studies were small and examined patients with cryptogenic cirrhosis (CC) who were assumed to have “burnt-out” NASH.15
Recent data suggest that approximately 3% of individuals from developed countries have NASH.16 Nine to 20% of patients who have NASH progress to cirrhosis, and up to one-third of these patients will die from complications from liver failure or require LT.1 It is not surprising then that NASH cirrhosis is projected to surpass HCV as the leading indication for LT in the next 10 years.17 With no foreseeable change in the number of deceased donor organs available for transplantation, maximizing the life of each allograft is critical.
The aims of the present study were 3-fold: first, to determine the incidence of recurrent NASH in patients transplanted for NASH cirrhosis; second, to determine if recurrent NASH affects graft or patient survival; and third, to determine what factors are predictive of recurrent disease.
PATIENTS AND METHODS
We retrospectively reviewed the records of all adult patients undergoing LT for a diagnosis of NASH cirrhosis with a prospectively collected database at a single center.
Patients were considered to have a diagnosis of NASH cirrhosis on the basis of histopathology and if they fulfilled the following clinical criteria: the absence of a history of alcohol and the exclusion of all other forms of chronic liver disease based on a combination of history, laboratory testing, histology, and an absence of potential exposures to hepatotoxins or medications associated with hepatic steatosis.
All patients underwent extensive serological testing prior to LT, including testing for hepatitis B virus (HBV; hepatitis B surface antibody, surface antigen, and core antibody), HCV (hepatitis C second-generation enzyme-linked immunosorbent assay, EIA-2, and HCV RNA), hemochromatosis (serum iron, saturation percentage, total iron binding capacity, ferritin, and HFE genetic testing if indicated), Wilson disease (ceruloplasmin levels), alpha 1-antitrypsin deficiency (alpha 1-antitrypsin levels and phenotype), autoimmune hepatitis (antinuclear antibody titers, anti–smooth muscle antibody titers, anti–liver-kidney microsomal antibody titers, and quantitative immunoglobulin levels: immunoglobulin G, immunoglobulin M, and immunoglobulin A), and primary biliary cirrhosis (PBC; antimitochondrial antibody titers).
All explant biopsy reports and available biopsy reports pre-transplant were reviewed to ensure findings consistent with NASH or NASH cirrhosis. Histological criteria for NASH included macrovesicular hepatic steatosis, Mallory's hyaline, ballooning degeneration, scattered predominantly neutrophilic inflammation, and pericentral, perisinusoidal fibrosis.18 Patients who did not undergo liver biopsy pre-transplantation or who did not have explant features diagnostic of NASH were excluded.
The collected demographic data included recipient characteristics [age, sex, race, body mass index (BMI), history of alcohol or illicit drug use, past medical history, laboratory data, Model for End-Stage Liver Disease (MELD) score, Child-Turcotte-Pugh (CTP) score, and dialysis or intubation pre-transplant], patient survival in days, retransplantation, and cause of death. Donor characteristics included age, sex, race, BMI, cause of death, and steatosis percentage on biopsy (when available). Surgical cold ischemia times and warm ischemia times were also noted. Immunosuppression was tacrolimus-based with or without the use of corticosteroids.
The length of stay post-transplant was defined as the number of hospital days (intensive care unit or otherwise) for patients who were eventually discharged from the hospital to home, rehabilitation, or a nursing facility. Patient survival was defined as short-term (24 hours and 30 days) and long-term (1, 3, and 5 years) from the time of LT.
A majority of the patients in our NASH cohort were biopsied because of clinical and biochemical concerns based on abnormal liver function studies or imaging. Since 2007, 1-year protocol biopsy has been implemented for patients transplanted for NASH cirrhosis. Acute cellular rejection (ACR) episodes (diagnosed by histopathology) and treatment with high-dose steroids were also noted.
Recurrent fatty liver disease was defined as the presence of macrovesicular or mixed macrovesicular/microvesicular steatosis with or without inflammation. Macrovesicular and mixed macro/microvesicular steatosis was graded on a scale of 0 to IV (0, no steatosis; I, <10%; II, 10%-33%; III, 33%-66%; and IV, >66% of hepatocytes with fat accumulation).
The diagnostic criteria for post-LT steatohepatitis were the same as those used to diagnose NASH pre-LT and are documented above.
Fibrosis was scored as follows: stage 0, none; stage I, expanded portal tracts, stage II, periportal fibrosis; stage III, bridging fibrosis; and stage IV, cirrhosis.
Patients with NASH cirrhosis were compared to patients in 4 control groups: in a 1:1 ratio with patients transplanted for CC and in a 1:2 ratio with patients transplanted for cholestatic liver disease [PBC and primary sclerosing cholangitis (PSC)], alcoholic liver disease (ALD), or HCV (total of 686 patients). The control groups were matched (in order of priority) for age, sex, Model for End-Stage Liver Disease score, and year of transplantation.
The most recent post-LT biopsy specimens in all 4 groups were used for comparison.
Continuous variables were compared with the Student t test. Categorical variables were compared with the chi-square test. Survival after LT was calculated with the Kaplan-Meier method and compared with the log-rank test. Data are expressed as means. All analysis was performed with Stata 8.0 (Statacorp, College Station, TX).
This study was approved by the institutional review board of the University of Pittsburgh.
Among the 2012 adult patients who underwent LT at our center from July 6, 1997 to June 28, 2008, we identified 143 patients with a diagnosis of NASH cirrhosis. After a thorough review and with the defined diagnostic criteria, 45 patients were eliminated for the following reasons: CC (n = 12), evidence of alpha 1-antitrypsin deficiency (n = 7), autoimmune hepatitis (n = 5), alcohol use (n = 5), hemochromatosis (n = 4), HCV (n = 3), HCV/ALD (n = 2), Wilson disease (n = 2), methotrexate-induced liver injury (n = 2), possible acetaminophen toxicity (n = 1), fulminant hepatic failure (n = 1), and HBV/ALD (n = 1); this left 98 patients (4.9% of the 2012 adults who underwent LT) transplanted with a primary diagnosis of NASH cirrhosis.
The baseline recipient and donor characteristics for all study patients (NASH and controls) have been described elsewhere.19
Seventy-one of 98 patients had pretransplant biopsy specimens consistent with a diagnosis of NASH. The remaining 27 patients included in the cohort had explant biopsy findings diagnostic for NASH. Of the 71 patients that had pre-LT biopsy specimens diagnosing NASH, 49 had explant findings consistent with NASH, whereas 32 (45%) had developed significant fibrosis or complete cirrhosis with few remaining diagnostic features of NASH.
Thirteen of the 98 NASH cirrhosis patients received live donor transplants. All patients post-LT (in both the NASH and control cohorts) were initially placed on tacrolimus-and prednisone-based immunosuppression.
Of the 98 patients, 79 (81%) underwent biopsy at a mean of 65 weeks post-LT. Twenty-one patients in the NASH cohort underwent yearly protocol biopsy. Fifty-five (69.6%) had evidence of fatty liver disease. Of the patients who underwent biopsy post-LT, 36 (45.6%) had bland steatosis, 19 (24.1%) had evidence of NASH (Fig. 1), and 14 (17.7%) had stage II/IV fibrosis or greater. No patients had histological evidence of cirrhosis. The earliest histological evidence of NASH was 4 weeks post-LT. The mean time frame from LT to the diagnosis of NASH was 73.4 ± 62.7 weeks (range: 4-234 weeks).
Of the 21 patients who underwent protocol biopsy, 16 had histological evidence of steatosis, and 6 had NASH. Seventeen of the 21 patients (80.9%) undergoing protocol biopsy had normal liver function tests, and the remainder had only minor elevations. Baseline recipient characteristics comparing patients with no histological evidence of steatosis (n = 24) to those with NASH (n = 19) are outlined in Table 1. Patients with no evidence of fatty liver post-LT were older and heavier pre-LT than those with NASH, but the pretransplant rates of diabetes mellitus (DM) and hypertension (HTN) were similar. Baseline donor characteristics between the 2 groups are compared in Table 2. Patients with recurrent NASH had a tendency to have younger donors. There was no difference in the donor steatosis percentage between the 2 groups.
|Nonsteatosis (n = 24)||NASH (n = 19)||P Value|
|Age (years)||62.1 ± 6.8 (range: 49-75; median: 63)||56.5 ± 6.4 (range: 40-67; median: 58)||<0.01|
|Sex (female)||18 (75.0%)||10 (55.5%)||NS|
|Race (white)||24 (100.0%)||18 (100.0%)||NS|
|BMI (kg/m2)||34.9 ± 7.1||30.9 ± 5.9||<0.05|
|BMI > 30 kg/m2||18 (75.0%)||11 (61.1%)||NS|
|DM||15 (62.5%)||12 (66.7%)||NS|
|HTN||14 (58.3%)||7 (38.9%)||NS|
|DM + HTN||11 (45.8%)||6 (33.3%)||NS|
|Albumin (g/dL)||2.9 ± 0.5||3.1 ± 0.6||NS|
|Creatinine (mg/dL)||1.4 ± 0.9||1.5 ± 1.1||NS|
|CTP score||8.7 ± 1.4||8.3 ± 1.7||NS|
|MELD||16.4 ± 6.5||15.7 ± 6.5||NS|
|Intubated||1 (4.2%)||1 (5.6%)||NS|
|Dialysis||2 (8.3%)||1 (5.6%)||NS|
|Nonsteatosis (n = 24)||NASH (n = 19)||P Value|
|Age (years)||52 ± 19.6||41.9 ± 13.0||0.07|
|Sex (female)||12 (50.0%)||7 (38.9%)||NS|
|Race (white)||22 (91.7%)||15 (83.3%)||NS|
|BMI (kg/m2)||29.7 ± 9.2||28.2 ± 5.6||NS|
|BMI > 30 (kg/m2)||10 (41.7%)||5 (27.8%)||NS|
|Live donor||3 (12.5%)||4 (22.2%)||NS|
|Steatosis (assuming no biopsy = 0%)||2.2% ± 4.1%||5.0% ± 7.2%||NS|
|Steatosis ≥ 20%||4 (16.7%)||1 (5.6%)||NS|
|CIT (minutes)||574.9 ± 230.1||573.3 ± 252.2||NS|
|WIT (minutes)||35.8 ± 19.6||29.3 ± 6.9||NS|
Of the 19 patients who had recurrent NASH post-LT, 6 (31.6%) had normal enzymes at the time of biopsy. The mean liver enzyme levels of the 19 patients with recurrent NASH were as follows: total bilirubin, 1.0 ± 0.7 (normal: 0.2-1.3 mg/dL); aspartate aminotransferase, 66 ± 59 (normal: 15-41 IU/L); alanine aminotransferase, 96 ± 86 (normal: 15-63 IU/L); alkaline phosphatase, 145 ± 94 (normal: 38-126 IU/L); and gamma glutamyl transferase, 216 ± 251 (normal: 0-41 IU/L).
With a mean follow-up of just over 3 years, no patient in the recurrent NASH cohort developed cirrhosis or graft failure. One-year mortality was significantly lower among patients with recurrent NASH (Table 3). Five-year survival was 83%. However, Kaplan-Meier 5-year survival curves illustrated no significant difference in survival between the 2 groups (Fig. 2). There was no difference in the length of stay post-LT.
|Nonsteatosis (n = 24)||NASH (n = 19)||P Value|
|Immediate (24 hours)||0||0||NS|
|30 days||1 (4.2%)||0||NS|
|1 year||7 (29.2%)||0||0.01|
|3 years||9 (33.3%)||2 (11.1%)||0.06|
|5 years||9 (33.3%)||3 (16.7%)||NS|
|LOS (days)||34.4 ± 30.2||22.2 ± 21.7||NS|
|Retransplant||2 (8.3%)||1 (5.6%)||NS|
At the time of postoperative biopsy, patients with NASH had a higher incidence of DM, dyslipidemia, and metabolic syndrome in comparison with those without histological evidence of steatosis (Table 3). Of the 19 patients who developed post-LT NASH, 12 gained weight from the time of transplant to the time of diagnosis of recurrent NASH (the mean weight gain was 4.0 kg), 2 developed de novo DM and HTN, and 4 developed new-onset hypertriglyceridemia (defined as serum triglycerides > 150 mg/dL). There was no difference in the number of episodes of ACR between patients with post-LT NASH and those without evidence of steatosis (Table 4). There was also no difference in the quantity or duration of steroid therapy between the 2 groups.
|Nonsteatosis (n = 24)||NASH (n = 19)||P Value|
|Δ BMI (kg/m2)||−1.4||+ 1.2||NS|
|Episodes of ACR||7||8||NS|
|Episodes of ACR treated with high-dose steroids||29||25||NS|
Of the 686 control patients, 569 (82.9%) underwent biopsy at a mean of 81 weeks post-LT. A comparison of the postoperative specimens with all 4 control groups showed that patients transplanted for NASH had a higher incidence of mild (grade I and II) steatosis (Table 5). The incidence of severe steatosis (grade IV) was higher in comparison with patients with PBC/PSC or HCV. The incidence of recurrent steatohepatitis was highest in the NASH group. The number of donors with greater than 20% steatosis was also highest in the NASH cohort. Of the 7 patients with high donor steatosis, 3 developed recurrent NAFLD, but only 1 developed recurrent NASH. There were more patients diagnosed with ACR in the PBC/PSC, ALD, and HCV groups in comparison with NASH (Table 5). The development of severe fibrosis/cirrhosis was highest in the HCV group. The rate of death from graft failure was higher in patients with ALD and HCV.
|Macro/mixed steatosis||NASH (n = 79)||PBC/PSC (n = 158)||ALD (n = 164)||HCV (n = 171)||CC (n = 76)|
|Donor steatosis ≥ 20%||8.9%||3.2% P = 0.04||4.3% NS||4.1% NS||1.3% P = 0.04|
|Steatosis 0||24.5%||62.7% P < 0.01||62.2% P < 0.01||51.5% P < 0.01||44.7% P = 0.05|
|Steatosis I||28.6%||29.7% NS||28.7% NS||40.9% NS||44.7% NS|
|Steatosis II||17.3%||3.2% P < 0.01||3.0% P < 0.01||1.8% P < 0.01||0.0% P < 0.01|
|Steatosis III||4.1%||3.2% NS||3.0% NS||4.7% NS||6.6% NS|
|Steatosis IV||6.1%||1.3% P = 0.01||3.0% NS||1.2% P = 0.01||3.9% NS|
|Steatohepatitis||24.1%||1.9% P < 0.01||4.9% P < 0.01||2.3% P < 0.01||5.3% P < 0.01|
|Fibrosis 0||31.6%||45.6% P = 0.03||45.1% P = 0.03||20.5% P = 0.04||47.4% P = 0.03|
|Fibrosis I||50.6%||34.8% P = 0.01||36.6% P = 0.03||32.7% P < 0.01||39.5% NS|
|Fibrosis II||10.1%||9.5% NS||7.9% NS||15.2% NS||9.2% NS|
|Fibrosis III||7.6%||8.3% NS||6.7% NS||16.4% P = 0.04||3.9% NS|
|Fibrosis IV||0||1.9% P = 0.29||3.7% P = 0.09||15.2% P < 0.0001||0 NS|
|Patients with at least 1 episode of ACR||26.6%||44.3% P < 0.01||38.4% P = 0.05||38.4% P < 0.05||36.8% NS|
|Death from graft failure||0.0%||4.2% P = 0.07||5.5% P = 0.03||8.9% P < 0.01||0.0%|
|Retransplantation as a result of disease recurrence||0.0%||3.0% NS||0.61% NS||2.2% NS||0.0% NS|
|Mean follow-up from transplantation to the most recent biopsy (days)||461.3 ± 446.7||603.8 ± 656.0 P = 0.07||586.4 ± 800.8 NS||583.0 ± 552.4 P = 0.07||501.8 ± 602.6 NS|
The present study demonstrates that recurrent disease is very common after LT for NASH cirrhosis. The incidence of recurrent steatosis at a mean follow-up of almost 18 months post-LT was 70%. Recurrent NASH is also not uncommon, with an incidence of approximately 25%, but recurrent disease in patients transplanted for NASH cirrhosis does not seem to lead to early patient death or graft failure. However, a significant number of patients developed stage II or greater fibrosis despite the relatively short follow-up period.
The only significant pre-LT factors associated with recurrent NASH were younger recipients and a lower BMI (Table 1), with a tendency for younger donors (Table 2). This would appear to be counterintuitive as NASH in a native liver is associated with a higher BMI and typically presents in older people. In addition, pretransplant DM and HTN were not more common in the recurrent NASH cohort, although overall these are very prevalent in NASH patients. However, at the time of posttransplant biopsy, patients with recurrent NASH were more likely to have developed DM, dyslipidemia, weight gain, and metabolic syndrome since the transplant (Table 4), and this suggests that the development of recurrent NASH after LT is associated with factors similar to those for NASH occurring in the native liver.1, 3
Nearly one-third of the patients with recurrent NASH had normal liver function tests at the time of diagnosis post-transplant. Fourteen of the 19 patients (73.7%) with recurrent NASH had aspartate aminotransferase/alanine aminotransferase ratios less than 1 (mean ratio: 0.69), which is similar to that seen in patients with NASH pre-LT.20 The poor correlation of liver enzymes with the diagnosis of NASH has been well documented in the pre-LT population,21, 22 and the current study suggests that the same is true post-LT. Because of the lack of reliability of blood work for the diagnosis of recurrence, we have adopted yearly protocol biopsy for patients transplanted for NASH in order to better monitor patients with more progressive disease.
Despite the frequency of recurrent disease, short-term mortality was not affected. There was a higher 1-year mortality rate in the recipients without steatosis (Table 3 and Fig. 2). We suspect that this is likely a reflection of a higher number of patients in the nonsteatosis group meeting criteria for what we previously concluded was high-risk NASH (a combination of older age and a higher BMI with pre-LT DM and HTN) and that this is independent of recurrent disease in the allograft.19 Inherently, patients with recurrent disease after LT have to live long enough for the recurrence to occur. The older donor age for the nonsteatosis recipients may also have been a factor in the higher early mortality seen in this cohort. With longer follow-up, there was no difference in mortality, and this suggests that deaths occurring in the recurrent NASH cohort occurred after 1 year (Table 3).
Not surprisingly, NASH patients were much more likely to develop recurrent steatosis and recurrent NASH than controls. Cryptogenic patients showed some similarities in steatosis and fibrosis rates, and this perhaps suggests that many of these patients actually had NASH as an underlying etiology. The highest fibrosis rates were seen in HCV patients, even after only 18 months of follow-up. This is not surprising given the universal incidence of recurrent disease in patients transplanted for HCV and, to a lesser extent, may be a reflection of aggressive diseases such as fibrosing cholestatic hepatitis. The progression of severe fibrosis post-LT in our HCV cohort was higher than that in previously published reports4 and may be a result of advanced age because the mean age of the patients in the current study was 60 years.
Despite an increased incidence of donor steatosis in the NASH cohort, this was not associated with recurrent NASH. The reasons for the higher donor steatosis in the NASH cohort compared to the controls are unclear, but because NASH is a more recent diagnosis, the higher donor steatosis may be a reflection of the general acceptance of more marginal allografts in the transplant community over the last few years.
ACR seems to be less of a problem in NASH recipients compared to controls (Table 4). All patients were on tacrolimus-and steroid-based immunosuppression, but three-quarters of NASH patients did not have a single episode of acute rejection. Although the incidence of ACR is highly variable and seems to be center-dependent, the overall incidence of ACR in our study population was consistent with previously published data.23 Besides lower levels of immunosuppression, several factors have been implicated in the development of ACR, including lower recipient age, fewer human leukocyte antigen donor matches, longer cold ischemia times, and cytomegalovirus status.24 Traditionally, ALD has been associated with a lower incidence of ACR, and conversely, autoimmune diseases such as PBC have been associated with a higher incidence.25 We could not relate any of the aforementioned recipient or donor factors to the lower incidence of ACR in our NASH cohort. Future studies may be warranted to further investigate this. Unlike previously published data,9 in our study, the use of steroids did not seem to be a risk factor for recurrent disease in patients transplanted for NASH (Table 3).
Recurrent disease post-LT is variable and is largely dependent on the etiology of the underlying liver disease. It is nearly universal in patients transplanted for HCV and is a significant cause of death, graft failure, and retransplantation,26 although there is evidence of improved outcomes with treatment.27 In contrast, recurrent disease has largely been reduced in patients with HBV with prophylactic regimens.28 In autoimmune liver diseases, recurrence can occur but rarely affects allograft survival,29–31 except for PSC, for which retransplantation rates of 15% can be seen, although it is unclear what percentage is a result of recurrent disease.32, 33 Alcohol recidivism post-LT for ALD rarely leads to early allograft failure, although it may increase the risk of long-term death from malignancy.34, 35 Hepatocellular carcinoma is a special case for which recurrence is largely dependent on tumor staging and genetic analysis pre-LT, with most recurrent cancers appearing within 3 years of LT.36–40
NASH cirrhosis is projected to become a leading indication for LT, and so it is imperative to better understand the incidence and impact of recurrent disease in this patient population. There have been at least 6 studies and case series looking at fatty liver post-LT,5, 8, 10–13 but a majority of these patients were transplanted with a diagnosis of CC (184 patients: 158 with CC and 28 with NASH). The incidence of the development of post-LT steatosis in these studies ranged anywhere from 25% to 100%, and the incidence of NASH ranged from as low as 10% to as high as 37.5%. Recurrent NASH occurred as quickly as 6 weeks in 1 patient,6 but most developed recurrence within 1 to 2 years post-LT. A handful of patients developed histological evidence of bridging fibrosis and cirrhosis, but only 1 patient with CC was retransplanted as the result of decompensation attributed to the development of severe NASH in the allograft.14
The current study demonstrates that mild steatosis (less than 10% steatosis) is very common post-LT, regardless of the etiology of the underlying disease, with an overall incidence of 34.9%. This corresponds to estimates of fatty liver disease in the general population.1–3
NASH patients who developed recurrent disease were initially treated with a combination of vitamin C, vitamin E, and ursodiol41 without obvious improvement, and 2 patients were started on pioglitazone after the recent study demonstrating its effectiveness in patients with NASH with or without insulin resistance.42, 43 It remains to be seen if this is effective therapy post-LT.
There are several limitations to the current study. We have only recently begun to perform protocol biopsy at our institution for patients transplanted for NASH. A majority of the patients biopsied in the study cohort were biopsied when there was concern about allograft disease, which was typically identified by abnormal liver enzymes. Nineteen patients were not biopsied post-transplant. We chose not to include nonbiopsied patients with normal liver function tests within the nonsteatosis subgroup. The current study and previous studies in which protocol biopsy was performed have demonstrated that normal biochemical profiles do not necessarily correspond to a lack of disease activity.5, 8 Thus, the current study likely underestimates the incidence of recurrent disease in patients with NASH. Another limitation of the study is the relatively short follow-up; the mean follow-up from the time of transplantation to the time of the most recent biopsy in patients with post-LT NAFLD was around 18 months, and the mean patient follow-up was only 3 years. It may be that allograft function deteriorates in NASH patients with recurrent disease after longer follow-up, particularly in patients who had already developed bridging fibrosis. Despite the short follow-up, 18% of the NASH patients developed stage II/IV or greater fibrosis, and this suggests that allograft cirrhosis is a real risk with longer follow-up. We have previously commented on the advanced age of patients transplanted for NASH cirrhosis versus other etiologies of chronic liver disease.19 With longer follow-up and older recipients, the histological progression of fatty liver disease post-transplant has to be a concern.
In conclusion, recurrent disease is relatively common post-LT for NASH cirrhosis at a mean follow-up of over 3 years, but this does not seem to lead to allograft failure or an increase in mortality. Nearly 1 of every 3 patients with recurrent NASH had normal enzymes at the time of diagnosis, and this argues for yearly protocol biopsy in this cohort to better monitor disease progression. New-onset diabetes, weight gain, and dyslipidemia after LT were associated with NASH recurrence. The development of stage II/IV or greater fibrosis in 18% of NASH patients after LT in the short follow-up period suggests that longer follow-up may lead to significant rates of allograft failure or the need for retransplantation.
- 21Nonalcoholic fatty liver disease in severely obese subjects. Am J Gastroenterol 2007; 102: 399–408., , , , .Direct Link:
- 23Acute cellular rejection after liver transplantation: variability, morbidity and mortality. Liver Transpl 2005; 15: 10–15., , .
- 33Long-term outcome of liver transplantation in patients with PSC: a comparative analysis with PBC. Am J Gastroenterol 2004; 99: 538–542., , .Direct Link:
- 39Predictors of long-term survival after liver transplantation for hepatocellular carcinoma. Am J Gastroenterol 2005; 100: 2708–2716., , , , , , et al.Direct Link: