Long-term follow-up after recurrence of primary biliary cirrhosis after liver transplantation in 100 patients

Liver transplantation for primary biliary cirrhosis in a hepatitis endemic region: a single-center Asian experience

From March 1984 to November 2008, we performed 539 primary liver transplantations (LTs). Nineteen (19, 3.5%) were transplanted for end-stage liver disease secondary to primary biliary cirrhosis (PBC). There were 17 (89%) female and 2 (11%) male recipients. The overall mean age was 50.3 ± 6.3 yr. The mean model for end-stage liver disease, and Child-Turcotte-Pugh scores were 20.7 ± 2.1, and 11.0 ± 0.5, respectively. There were 2 (11%) United Network for Organ Sharing status 3, 16 (84%) 2B, and 1 (5%) 2A patients. Fourteen patients (14, 73.7%) underwent living donor LT, and five patients (26.3%) received deceased donor LT. The primary immunosuppression consisted of cyclosporine (n = 5) and tacrolimus (n = 14). Liver function returned to normal one month after transplantation. The overall mean follow-up was 5.8 ± 0.8 yr (range, four months to 15.7 yr). The overall one-, three-, and five-yr survival rates were 94.7%, 89.2%, and 89.2%, respectively. Without hepatitis B virus (HBV) prophylaxis, one patient acquired de novo HBV infection after receiving a graft from an anti-HBc(+) donor. Another patient developed recurrent hepatitis C infection and expired 25 months after transplantation. Our results showed that HBV prophylaxis was effective not only against de novo infection, but it also worked on pre-transplant HBV carrier with PBC and helped in virus clearance.

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.

Recurrent primary biliary cirrhosis after liver transplantation

Recurrent primary biliary cirrhosis (PBC) is an important clinical outcome after liver transplantation (LT) in selected patients. Prevalence rates for recurrent PBC (rPBC) reported by individual LT programs range between 9% and 35%. The diagnostic hallmark of rPBC is histologic identification of granulomatous changes. Clinical and biochemical features are frequently absent with rPBC and cannot be used alone for diagnostic purposes. Some of the risk factors of rPBC may include recipient factors such as age, gender, HLA status and immunosuppression, as well as donor factors such as age, gender and ischemic time, although controversy exists. Most patients have early stage disease at the time of diagnosis, and there may be a role for therapy with ursodeoxycholic acid. While short- and medium-term outcomes remain favorable, especially if compared to patients transplanted for other indications, continued follow-up may identify reduced long-term graft and patient survival.

Cyclosporine A protects against primary biliary cirrhosis recurrence after liver transplantation

Primary biliary cirrhosis (PBC) reoccurs in a proportion of patients following liver transplantation (LT). The aims of our study were to evaluate the risk factors associated with PBC recurrence and determine whether recurrent disease constitutes a negative predictor for survival. One hundred and eight patients receiving LT for end-stage PBC were studied. Recurrent disease was diagnosed in 28 patients (26%). Probability of recurrent PBC at 5 years was 13% and 29% at 10 years with an overall incidence of 3.97 cases per 100 patient years. By univariate Cox analysis use of tacrolimus (HR 6.28, 95% CI, 2.44-16.11, p < 0.001) and mycophenolate mofetil (HR 5.21, 95% CI, 1.89-14.33, p = 0.001) were associated with higher risk of recurrence; whereas use of cyclosporine A (CsA) and azathioprine were associated with reduced risk of recurrence (HR 0.13, 95% CI 0.05-0.35, p < 0.001 and HR 0.27, 95% CI 0.11-0.64, p = 0.003, respectively). In the multivariate Cox analysis, only CsA was independently associated with protection against recurrence (HR 0.17, 95% CI 0.06-0.71, p = 0.02). Five-year probability of survival was 83% and 96%, in patients without and with recurrence (log-rank test, p = 0.3). Although PBC transplant recipients receiving CsA have a lower risk of disease recurrence, the development of recurrent PBC did not impact on long-term patient survival.

Primary biliary cirrhosis after liver transplantation: influence of immunosuppression and human leukocyte antigen locus disparity

Patients with primary biliary cirrhosis (PBC), despite excellent outcomes after liver transplantation (LT), may develop recurrent primary biliary cirrhosis (rPBC). The impact of immunosuppression and HLA mismatches on rPBC is unclear. We evaluated 103 consecutive PBC patients who underwent transplantation (follow-up > or = 10 months) with serial protocol biopsies. Cox regression was used to evaluate factors associated with rPBC: the Model for End-Stage Liver Disease score pre-LT, year of transplantation, age and gender of the recipient and donor, cold and warm ischemic times, HLA mismatches, rejection, infections, and immunosuppression (initial/maintenance). The mean follow-up was 108 months (10-239 months), rPBC occurred in 36, and the mean was 44 months (10-200 months). Immunosuppression was cyclosporine-based in 38 (10 initially on monotherapy) and tacrolimus-based in 62 (19 initially on monotherapy). Steroids were discontinued in all but 7. Azathioprine was part of the initial immunosuppression in 70, 26 discontinued it, and 33 were never exposed to it. rPBC was associated independently with nonuse/discontinuation of azathioprine (P = 0.015, hazard ratio = 0.046, 95% confidence interval = 0.008-0.261). The mean time to rPBC was 74 months with azathioprine, 43 months when AZA was discontinued, and 31 months if no azathioprine was used. Cyclosporine or tacrolimus alone had no impact on rPBC, but cyclosporine with azathioprine was protective for rPBC in comparison with tacrolimus/azathioprine (0/18 versus 7/25, respectively; P < 0.001). rPBC was not affected by HLA mismatches. Azathioprine use in PBC patients who underwent transplantation was associated with less disease recurrence and a longer time to rPBC. Tacrolimus or cyclosporine individually had no effect, but cyclosporine and azathioprine in combination resulted in the least rPBC.

Recurrent disease following liver transplantation for nonalcoholic steatohepatitis cirrhosis

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.

Recurrence of autoimmune disease, primary sclerosing cholangitis, primary biliary cirrhosis, and autoimmune hepatitis after liver transplantation

1. Recurrence of primary sclerosing cholangitis. a Five percent of liver transplants are performed because of end-stage liver disease secondary to primary sclerosing cholangitis. b Recurrent disease affects 10% to 27% of recipients. c Diagnostic criteria of recurrence include the following: A confirmed diagnosis of primary sclerosing cholangitis before liver transplantation. A cholangiogram showing nonanastomotic biliary strictures with beading and irregularity occurring 90 days after transplantation. Liver biopsy revealing fibrous cholangitis and/or fibro-obliterative lesions of large bile ducts. d The data argue for an association between recurrent primary sclerosing cholangitis and rejection and steroid therapy. 2. Recurrence of primary biliary cirrhosis. a Overall recurrence rates can reach 50%. b The gold standard for diagnosis is histological, with bile duct destruction by granulomas indicated by a florid lesion. c Anti-mitochondrial antibody is not a reliable marker of recurrence. d Recurrence does not affect long-term patient or graft survival. 3. Recurrence of autoimmune hepatitis. a Recurrence affects approximately 25% of liver allografts during the first 5 years after liver transplantation and more than 50% after 10 years of follow-up. b Diagnostic criteria of recurrence must include a combination of biochemical changes, (elevated serum aminotransferases levels and hypergammaglobulinemia), histological features of autoimmune hepatitis, and steroid dependency. c Immunosuppressive therapy should be pursued even if liver test results are normal.

Liver transplantation

Liver transplantation has become a lifesaving procedure for patients who have chronic end-stage liver disease and acute liver failure. The satisfactory outcome of liver transplantation has led to insufficient supplies of deceased donor organs, particularly in East Asia. Hence, East Asian surgeons are concentrating on developing and performing living-donor liver transplantation (LDLT). This review article describes an update on the present status of liver transplantation, mainly in adults, and highlights some recent developments on indications for transplantation, patient selection, donor and recipient operation between LDLT and deceased-donor liver transplantation (DDLT), immunosuppression, and long-term management of liver transplant recipients. Currently, the same indication criteria that exist for DDLT are applied to LDLT, with technical refinements for LDLT. In highly experienced centers, LDLT for high-scoring (>30 points) Model of End-Stage Liver Disease (MELD) patients and acute-on-chronic liver-failure patients yields comparably good outcomes to DDLT, because timely liver transplantation with good-quality grafting is possible. With increasing numbers of liver transplantations and long-term survivors, specialized attention should be paid to complications that develop in the long term, such as chronic renal failure, hypertension, diabetes mellitus, dyslipidemia, obesity, bone or neurological complications, and development of de novo tumors, which are highly related to the immunosuppressive treatment.

Recurrence of primary biliary cirrhosis and development of autoimmune hepatitis after liver transplant: A blind histologic study

AIM

This long-term study aimed to evaluate recurrence and evolution of primary biliary cirrhosis (PBC) after orthotopic liver transplantation (OLT).

METHODS

We reviewed "blindly" allograft biopsy specimens of women who underwent transplantation for PBC (n = 84), and women who received a transplant for chronic hepatitis C virus infection (CHCV ) (n = 108). All needle liver biopsy specimens obtained more than 6 months post-OLT were examined, including 83 specimens from 44 PBC patients and 152 specimens from 58 CHCV patients.

RESULTS

Granulomatous destructive cholangitis was found in five biopsies from four PBC patients (P = 0.0048). Non-necrotizing epithelioid cell granulomas were present in four biopsies from four PBC patients, and in two biopsies from one CHCV patient. Piecemeal necrosis (P = 0.0002), lobular necroinflammatory activity (P < 0.0001), steatosis (P < 0.0001) and fibrosis (P < 0.0001) were more prevalent in CHCV patients than PBC patients. Four PBC patients developed histologic evidence of autoimmune hepatitis (AIH), at a mean time of 3.66 years post-OLT. One of these patients had histologic features of AIH/PBC overlap syndrome. All four patients developed bridging fibrosis (n = 2) or cirrhosis (n = 2). No other PBC patient had evidence of cirrhosis after OLT.

CONCLUSIONS

Histologic findings indicative of recurrent PBC were present in 15.9% of the PBC patients undergoing biopsy in this series. However, this group of patients did not suffer significant bile duct loss or fibrosis, as compared to the control group, suggesting that recurrent PBC is a mild or slowly progressive disease. Histologic evidence of AIH was observed in allograft biopsies of some PBC patients.

Protocol liver allograft biopsies

Protocol liver allograft biopsies are liver biopsies carried out at specific time points according to predetermined guidelines, rather than in response to specific indications such as change in the patient's clinical status or biochemical tests. Use of protocol liver allograft biopsy has been declining over the last decade: an informal survey of 35 transplant units showed that whereas 65% of units undertake protocol biopsies for those grafted for Hepatitis C virus infection, only 25% do so for patients grafted for other indications. In this overview, we consider the arguments against and those in favor of liver biopsies in adult liver allograft recipients. Arguments against the use of protocol liver biopsies are that they biopsies put the patient are associated with a small risk of morbidity and mortality, are expensive, do not provide useful information and do not alter clinical practice. The estimated rate of major complications is 0.6% and the estimated mortality rate 0.02%. However, the argument in favor of protocol biopsies is that even when standard liver tests are normal, there is on-going inflammation in the graft which, if immunosuppression is not altered, will lead to progressive fibrosis, cirrhosis and even graft loss. Conversely, normal liver histology may allow for reduction in the immunosuppression and so lower the risk of the complications associated with immunosuppression. Currently available diagnostic techniques are not yet sufficiently sensitive or specific to provide an accurate reflection of the state of the graft and the presence or absence of graft damage. We conclude that, while there are no clear data showing that protocol liver allograft biopsies are cost effective and lead to improved patient and graft outcome, such biopsies still have a role in the management of the liver transplant recipient.

Recurrent acute liver failure and mitochondriopathy in a case of Wolcott-Rallison syndrome

A 10-year-old Arabic boy of consanguineous parents has suffered eight episodes of acute liver failure with haemolysis triggered by intercurrent febrile illnesses. The first crisis occurred at 9 months of age, after which diabetes mellitus developed. By the age of 6 years, short stature, mild myopathy and later skeletal epiphyseal dysplasia also became evident. His psychosocial development and educational achievements have remained within normal limits. While there were no clear biochemical indicators of a mitochondrial disorder, an almost complete deficiency of complex I of the respiratory chain was demonstrated in liver but not in fibroblast or muscle samples. Molecular analysis of the eukaryotic translation initiation factor 2alpha kinase gene (EIF2AK3) demonstrated a homozygous mutation, compatible with a diagnosis of Wolcott-Rallison syndrome (WRS). This patient's course adds a new perspective to the presentation of WRS caused by mutations in the EIF2AK3 gene linking it to mitochondrial disorders: recoverable and recurrent acute liver failure. The findings also illustrate the diagnostic difficulty of mitochondrial disease as it cannot be excluded by muscle or skin biopsy in patients presenting with liver disease. The case also further complicates the decision-making process for liver transplantation in cases of acute liver failure in the context of a possible mitochondrial disorder. Such patients may be more likely to recover spontaneously if a mitochondrial disorder underlies the liver failure, yet without neurological features liver transplantation remains an option.

Histologic abnormalities are common in protocol liver allograft biopsies from patients with normal liver function tests

The utility of protocol liver allograft biopsies remains controversial, particularly in patients with normal liver function tests (LFTs). However, histologic evaluation of these biopsies provides an opportunity to examine the types and severity of liver diseases that can occur in livers with normal clinical and biochemical function. We studied 165 protocol allograft biopsies taken from 100 liver transplant patients at the time of normal LFTs and normal clinical function at 3 to 8 months (n=36), 1 year (n=52), 2 to 3 years (n=54), and 4 to 5 years (n=23). Biopsies were classified as normal, minimal changes (eg, nonaggressive portal or lobular mononuclear inflammation, steatosis <10%), fatty liver disease, recurrent primary liver disease, and transplant-related disease (portal-based rejection or central venulitis, an inflammatory pattern that encompasses perivenular hepatocyte dropout, mononuclear inflammation, pigment-laden macrophages, and variable zone 3 fibrosis). Among these 100 patients, a total of 394 protocol biopsies were performed, and 165 (42%) were taken at the time of normal LFTs and normal clinical function. One hundred twenty-one (73%) were normal or showed minimal/nonspecific changes. Forty-four (27%) showed histologic abnormalities that included fatty liver disease (n=19, nonalcoholic in 18 cases; 13 with mild steatosis, 6 with moderate steatosis, 7 with grade 1/3 steatohepatitic activity, and 2 with stage 1/4 steatohepatitic fibrosis), recurrent primary biliary cirrhosis (n=9; all stage 1/4), recurrent hepatitis C infection (n=6; grade 0/4 in 1, grade 1/4 in 5, stage 0/4 in 4, stage 1/4 in 1, and stage 2/4 in 1), recurrent sarcoidosis (n=1), Ito cell hyperplasia (n=4; marked in 2 and mild in 2), central venulitis (n=10; 5 with mild zone 3 fibrosis or central vein obliteration and 1 with central-portal bridging fibrosis), and mild acute portal rejection (n=2). We judged the histologic changes to be of clinical significance in 19 (11.5%) cases. These results indicate that even at the time of normal clinical and laboratory function, a significant fraction of protocol allograft biopsies harbor histologic (27%) and clinically significant (11.5%) abnormalities. These most commonly include fatty liver disease, low-grade/low-stage recurrent hepatitis C and primary biliary cirrhosis, and central venulitis (including some cases with subsequent fibrosis progression). The data support performance of protocol biopsies to assess allograft status, and provide insight into the types and severity of liver diseases that can smolder in transplanted (and by extension, probably also in native) livers with apparent normal function.

Transplantation in autoimmune liver diseases

Liver transplantation remains an effective treatment for those with end-stage disease and with intractable liver-related symptoms. The shortage of organs for transplantation has resulted in the need for rationing. A variety of approaches to selection and allocation have been developed and vary from country to country. The shortage of donors has meant that new approaches have to be adopted to make maximal use of the available organs; these include splitting grafts, use of extended criteria livers, livers from non-heart-beating donors and from living donors. Post transplantation, most patients will need life-long immunosuppression, although a small proportion can have immunosuppression successfully withdrawn. Newer immunosuppressive drugs and different strategies may allow a more targeted approach with a reduction in side-effects and so improve the patient and graft survival. For autoimmune diseases, transplantation is associated with significant improvement in the quality and length of life. Disease may recur after transplantation and may affect patient and graft survival.

Liver transplantation in primary biliary cirrhosis

The proportion of patients who undergo liver transplantation for primary biliary cirrhosis (PBC) is steadily declining. This decline is partly from the increasing number of patients undergoing transplantation for other indications, but also perhaps because of the effect of ursodeoxycholic acid (UDCA) on the natural history of this condition. Nevertheless, patients who have PBC still constitute approximately 11% of all patients undergoing transplantation for cirrhosis. The prognosis after transplantation is excellent, with an approximately 80% 5-year survival reported by most large centres. Liver transplantation also significantly improves quality of life in survivors. The disease may recur after surgery in up to one third of patients, but recurrence has not been shown to have a significant effect on patients' survival in the medium term.

Intrahepatic cholestasis after liver transplantation

Biochemical cholestasis after liver transplantation is common and often has no clinical significance if biliary anastomosis strictures and leaks have been excluded. There is no agreed upon definition for severe cholestasis, but it is associated with a worse mortality. There has been little evaluation on risk factors, but these include cryoprecipitate and platelet transfusion intraoperatively, nonidentical blood group, suboptimal graft appearance, inpatient status before transplant, and bacteremia within the first month. Associated causes considered as early (<6 months) include ischemia-reperfusion injury, primary nonfunction, small-for-size graft syndrome, infection, drugs and acute cellular rejection. Late causes include hepatic artery thrombosis, chronic rejection, biliary complications, recurrent viral and cholestatic disease, and posttransplant lymphoproliferative disorder.

Long-term clinical outcome of living-donor liver transplantation for primary biliary cirrhosis

AIM

We described the recurrence of primary biliary cirrhosis (PBC) after living donor liver transplantation (LDLT) (Liver Transplantation, 7, 2001: 588). However, since the follow-up period in that study was insufficiently long (median 35.5 months), we performed a long-term study to further characterize recurrence of PBC after LDLT.

PATIENTS

From 1991 to 2006, 15 patients with end-stage PBC underwent LDLT at Tokyo Women's Medical University. Of these patients, we studied 8 PBC patients (age 29 to 51 years, all females) who survived LDLT for more than 5 years. The follow-up period for these patients ranged form 68 to 120 months. Immunosuppression was maintained with tacrolimus and prednisone. Laboratory examinations performed in every patient and donor before LDLT included routine biochemical studies, antimitochondrial antibody (AMA) by immunofluorescence (IF), anti-M2 by enzyme-linked immunosorbent assay as well as antinuclear antibody (ANA) by IF, and immunoglobulin. After LDLT, the same laboratory examinations were performed in patients every 6 months. Liver biopsy was performed when patients exhibited clinical or biochemical signs of graft dysfunction. In addition, protocol biopsy was performed every 1 to 2 years after LDLT.

RESULTS

At the time of LDLT, all patients had end-stage cholestatic liver failure. Seven patients were positive for AMAand anti-M2 while 1 patient was negative for these markers but strongly positive for ANA. Donors were blood relatives in 6 cases, and 2 donors who were not blood relatives still exhibited multiple HLA matches with the recipients. At the end of the study in May 2006, all patients were doing well. On laboratory examination, mild abnormal liver function test results were found in 4 patients: 3 were probably due to recurrence of PBC, 1 resulted from nonalcoholic steatohepatitis. Comparison of the AMA titer between before LDLT and the most recent follow-up visit showed an increase in three patients, a decrease in two patients and no change in three patients. In contrast, the ANA titer increased in five patients. Histologically, strong evidence of recurrent PBC was found in 4 patients, and findings compatible with PBC were present in 2 additional patients.

CONCLUSIONS

Although the number of our patients is small, our findings confirm that PBC can recur at high frequency after LDLT. However, this complication has not developed to advanced stages and has not caused appreciable symptoms in our patients, all of whom have a good quality of life.

Long-term survival and impact of ursodeoxycholic acid treatment for recurrent primary biliary cirrhosis after liver transplantation

The recurrence of primary biliary cirrhosis (PBC) in the hepatic allograft may impact patient and graft survival with long-term follow-up. The efficacy of ursodeoxycholic acid (UDCA) for treatment of recurrent PBC after liver transplantation (LT) remains less well known. The aims of this study were as follows: 1) to determine the significance of recurrent PBC on overall survival among PBC patients who underwent LT, and 2) to determine the efficacy of UDCA treatment after LT in patients with recurrent PBC. A retrospective cohort study was conducted of 154 PBC patients who underwent LT with at least 1 yr of follow-up after transplantation from 1985 through 2005. A total of 52 patients with recurrent PBC were identified. After adjusting for age and gender, recurrent PBC was not associated with death or liver retransplantation (hazard ratio, 0.97, 95% confidence interval, 0.41-2.31; P = 0.9). A total of 38 patients with recurrent PBC received UDCA at an average dose of 12 mg/kg/day for a mean duration of 55 months. Over a 36-month period, an estimated 52% of UDCA-treated patients experienced normalization of serum alkaline phosphatase and alanine aminotransferase compared to 22% of untreated patients. There was no significant difference in the rate of histological progression between subgroups. UDCA did not influence patient and graft survival. In conclusion, the development of recurrent PBC has little impact on long-term survival or need for retransplantation. While UDCA therapy is associated with biochemical improvement, its role in delaying histologic progression remains unknown. In this short period of treatment, UDCA was not associated with improved patient and graft survival compared to untreated patients.

Cholestasis and cholestatic syndromes

PURPOSE OF REVIEW

This review focuses on the recent advances in cholestatic liver diseases. While there is an emphasis placed on translational and treatment-focused studies, basic science studies with the greatest impact on the field are also covered.

RECENT FINDINGS

Highlights include new discoveries for the role of the farsenoid X receptor and sodium-dependent taurocholate cotransporting polypeptide; new insights into the pathogenesis of progressive familial intrahepatic cholestasis type 1, biliary atresia, intrahepatic cholestasis of pregnancy, and primary biliary cirrhosis; new information for assessing prognosis in biliary atresia and primary biliary cirrhosis; and important clinical trials in intrahepatic cholestasis of pregnancy, primary biliary cirrhosis and primary sclerosing cholangitis.

SUMMARY

The studies of 2006 have furthered our understanding of cholestasis and cholestatic syndromes. While we continue to add to our knowledge of pathogenesis and treatment for many of these diseases, much work remains.