Objectives: Patients who have a liver transplant for primary sclerosing cholangitis may develop recurrent disease and biliary complications, organ loss necessitating revision liver transplant, or death. We evaluated long-term outcomes in patients who had liver transplant for primary sclerosing cholangitis.

Materials and Methods: In 71 patients who had a liver transplant for end-stage liver disease because of primary sclerosing cholangitis, a retrospective review was done to evaluate biliary complication-free survival, transplanted organ survival, and death. Human leukocyte antigen typing and matching were reviewed.

Results: There were 39 patients (55%) who had biliary complications, loss of the liver transplant, or death at a mean 12.1 years after transplant. The 5- and 10-year event-free survival reached 74.6% and 45% (53 patients after 5 years, and 32 patients after 10 years). Male sex of transplant recipients was a significant risk factor for biliary complications, revision liver transplant, or death. Most patients had inflammatory bowel disease, primarily ulcerative colitis. The human leukocyte antigen profile or number of mismatches had no effect on complication-free survival.

Conclusions: Biliary complications, revision liver transplant, and death are a useful combined primary endpoint for recurrent primary sclerosing cholangitis after liver transplant.

Key words : Human leukocyte antigen, Ulcerative colitis, Immunosuppression, Hepatic failure

Introduction

Among diseases leading to orthotopic liver transplant, primary sclerosing cholangitis is associated with good long-term outcome. Although, overall 10-year patient survival after orthotopic liver transplant is approximately 70% (organ survival, 60%),¹ patients who have transplant for primary sclerosing cholangitis have patient survival 79% and organ survival 68%. Yet, primary sclerosing cholangitis can recur in 2% to 40% patients.² The varied frequency of recurrence results from differences in follow-up protocols and duration in different studies. Published criteria for recurrent primary sclerosing cholangitis are frequently used.³ Disease-free survival ends with histologic proof of recurrent primary sclerosing cholangitis, with fibrous cholangitis, fibrous and stenosing lesions of the bile ducts with or without histologic proof of recurrent primary sclerosing cholangitis, with biliary fibrosis, or cirrhosis (Table 1). In addition, cholangiographic findings on endoscopic retrograde cholangiography⁴ or magnetic resonance cholangiography⁵ have been used for diagnosis of recurrent primary sclerosing cholangitis.

After orthotopic liver transplant, recurrent primary sclerosing cholangitis may develop but sometimes the diagnosis may not be easily confirmed. Other syndromes may have comparable clinical findings, including irregular strictures of the biliary tree and repeated episodes of cholangitis that require endoscopic treatment. This may occur with ischemic type biliary lesions and ischemic biliary lesions associated with hepatic artery stenosis or thrombosis.⁶ The diagnosis of ischemic type biliary lesions is based primarily on morphologic findings, but nonenhancement or hypoenhancement of the hilar bile duct walls during the arterial phase of contrast-enhanced ultrasonography may facilitate diagnosis and may have acceptable sensitivity and specificity.⁷ However, the diagnosis may be difficult, and histopathologic features in routine biopsies may show either ischemic type biliary lesions or recurrent primary sclerosing cholangitis in 24% patients, with only approximately 50% patients having biliary morphologic alterations and stenosing bile ducts.⁸ Furthermore, chronic rejection with vanishing bile ducts or ascending cholangitis after hepatico­jejunostomy may clinically resemble recurrent primary sclerosing cholangitis. All these conditions have similar clinical presentation and treatment and may cause loss of the transplanted liver with either the need for revision transplant or death of the patient.⁹

Risk factors for recurrent primary sclerosing cholangitis after orthotopic liver transplant include sex mismatch,¹⁰ male sex,¹¹ steroid-resistant acute cellular rejection,^5,12 and inflammatory bowel disease. After orthotopic liver transplant, up to 60% patients have progressive inflammatory bowel disease¹³ and some patients develop de novo ulcerative colitis. Severe or de novo ulcerative colitis after orthotopic liver transplant is a risk factor for recurrent primary sclerosing cholangitis, and colectomy before orthotopic liver transplant may be protective against recurrent primary sclerosing cholangitis.¹⁴ However, conflicting results have been reported.¹⁵

Several human leukocyte antigen (HLA) loci have been linked to primary sclerosing cholangitis.^16-20 The HLA-C locus, a risk factor for primary sclerosing cholangitis, acts as a ligand for killer cell immuno­globulinlike receptors expressed on natural killer (NK) cells and some T lymphocytes and affects cytotoxicity.¹⁸ The HLA-C alleles are grouped according to major killer cell immunoglobulinlike receptor epitopes C1 (which acts as a ligand for killer cell immunoglobulinlike receptor 2DL2/3) and C2 (which binds killer cell immunoglobulinlike receptor 2DL1).^19,20 They differ at position 80 of the α1 helix that carries asparagine (C1) or lysine (C2) at this position. Although the interaction between C1 and killer cell immunoglobulinlike receptor 2DL2/3 weakly inhibits NK cells, the interaction between C2 and killer cell immunoglobulinlike receptor 2DL1 strongly inhibits NK cells, and C2 expression is reduced in patients who have primary sclerosing cholangitis compared to control subjects.²¹

Recurrent primary sclerosing cholangitis after orthotopic liver transplant is associated with HLA-DRB1*08 (DR8) but not with DR3- and DQ2-heterozygosity or DR6.²² In contrast with the first occurrence of primary sclerosing cholangitis,²³ there is controversy about the effect of human leukocyte antigen disparity between donor and recipient on recurrence of primary sclerosing cholangitis. The risk of recurrent primary sclerosing cholangitis is increased by mismatch at the A locus and decreased by mismatch at the DR locus.^12,24,25 The effect of HLA-C on liver transplant is controversial. Although the HLA-C2 genotype of donors may positively affect chronic rejection and graft cirrhosis,²⁶ there is no effect of HLA-C2 genotype on long-term outcome.²⁷

Although patients who have liver transplant for primary sclerosing cholangitis may have good long-term survival, there is potential morbidity for biliary complications, especially in young patients who often have minor comorbidities. European and American patients who have primary sclerosing cholangitis typically are aged 47 ± 14 years and have mean Model for End-Stage Liver Disease score of 15 ± 8.²⁸ It may be difficult to determine the correct diagnosis because of clinical similarities between recurrent primary sclerosing cholangitis, ischemic type biliary lesions, ischemic biliary lesions, and chronic rejection. Therefore, we focused on biliary complications after orthotopic liver transplant as the primary endpoint for disease-free survival. Although all biliary complications may compromise patients equally, anastomotic strictures must be excluded because these strictures may be caused by technical problems during transplant and not systemic disease (Figures 1-3).

Materials and Methods

Patient cohort and perioperative features
Between December 1988, and October 2010, there were 2493 patients who had liver transplant at our institution, including 99 patients who had liver transplant for primary sclerosing cholangitis. In the present study, we retrospectively reviewed 83 patients who had liver transplant between December 1988, and December 2003, for end-stage liver disease caused by primary sclerosing cholangitis. There were 12 patients who were excluded: 6 patients who had early revision transplant (within 90 days of primary transplant); 3 patients who had known cholangiocarcinoma; and 3 patients who were lost to follow-up. The remaining 71 patients were mostly male patients who had inflammatory bowel disease (Table 2).

Demographic and clinical data were recorded for each patient including comorbidities such as inflammatory bowel disease and previous hepa­to-biliary or colorectal surgery. Preoperative autoantibodies (antimitochondrial antibody, antinuclear antibody, smooth muscle antibody, and perinuclear antineutrophil cytoplasmic antibody) were recorded. Information was recorded about donor characteristics (age, sex, and ABO blood type), sex mismatch, preservation injury (graded 1 to 3: 1 = little, 2 = moderate, 3 = severe), transplant type (deceased-donor full size, living-related split, or deceased-donor split), and type of biliary anastomosis (biliodigestive [Roux-en-Y choledochojejunostomy] or duct-to-duct). The postoperative immunosuppressive drugs used and information about graft rejection episodes, treatment of graft rejection, human leukocyte antigen profile of donor and recipient, and cause of loss of transplanted liver or death were recorded.

Patients were evaluated for biliary complication-free, liver transplant, and patient survival. Patients who had biliary complications, revision orthotopic liver transplant, or death were compared to patients who had no complications.

Postoperative treatment
All biliary interventions for causes except anastomotic strictures qualified as a biliary complication. These interventions included endoscopic retrograde cholangiography with dilation, removal of sludge, placement of a stent proximal to the anastomosis, and percutaneous transhepatic cholangiographic drainage. Patients who had intraductal cholangio-carcinoma diagnosed before orthotopic liver transplant or detected at explant were excluded from the analysis. Presence of other malignant diseases and relevant comorbidities after orthotopic liver transplant were recorded.

Protocol liver biopsies were obtained at 1, 3, 5, 7, and 10 years after transplant with patient agreement or for evaluation of suspected acute cellular rejection. Evaluation of suspected recurrent primary sclerosing cholangitis included magnetic resonance cholangio-graphy combined with liver biopsy. Laboratory studies during the first 21 days after transplant included aspartate aminotransferase, alanine transaminase, total bilirubin, gamma-glutamyl transpeptidase, and alkaline phosphatase. During follow-up, frequency of laboratory testing was decreased from twice weekly during the first 2 postoperative months to once monthly after 4 months, but more frequent testing was done in patients who had clinical problems or elevated test results.

Acute cellular rejection and immunosuppression
Rejection episodes were diagnosed by liver biopsy according to established histologic criteria.²⁹ Acute cellular rejection (Banff grade ≥ 1) was treated with methylprednisolone (1 g, intravenous, for 3 days), and steroid-resistant rejection (diagnosed after repeat biopsy) was treated with muromonab-CD3. Usually steroids were tapered within 3 months and initial immunosuppressive therapy included tacrolimus or cyclosporine, as well as mycophenolate mofetil or azathioprine in several patients.

Inflammatory bowel disease
The features of inflammatory bowel disease were recorded including diagnosis, duration of disease before orthotopic liver transplant, course after orthotopic liver transplant including number of hospital admissions, type of bowel surgery before and/or after orthotopic liver transplant, progression of disease, and the need for steroid treatment. Patients had annual surveillance with colonoscopy (and esophagogastroduodenoscopy for Crohn disease).

Human leukocyte antigen type
The human leukocyte antigen type was determined serologically with lymphotype trays (ABC 144 Italia, Bio-Rad, Munich, Germany). Lymphocytes were isolated by Ficoll gradient centrifugation, and lymphocyte suspension (1 μL) was added to the wells of the typing trays. After incubation (30 min), rabbit complement (5 μL) (Bio-Rad, Munich, Germany) was added and the trays were incubated for 70 minutes at room temperature. Cells were stained (FluoroQuench vital stain, One Lambda, Canoga Park, CA) and analyzed with a fluorescence microscope. Complete human leukocyte antigen type determination was possible for 61 recipient-donor pairs for HLA-A and HLA-B and for 57 recipient-donor pairs for HLA-DR; however, type HLA-DQ could not be determined in most donors and recipients and was not assessed for mismatching frequencies in this study. Each patient was examined for the number of mismatches at any locus (HLA-A, HLA-B, and HLA-DR), and the total numbers of mismatches per individual for all loci together (except HLA-C) were grouped as 0 to 2, 3 to 4, or 5 to 6 mismatches. Determination of HLA-C type was available for only 31 recipient-donor pairs and not available for 20 donors and 27 recipients; the HLA-C alleles were grouped according to major killer cell immunoglobulinlike receptor-epitopes C1 and C2 and results were evaluated for the effect of donor and recipient genotype on complications. The human leukocyte antigen characteristics of patients were analyzed for pretransplant primary sclerosing cholangitis and recurrent primary sclerosing cholangitis after orthotopic liver transplant.

Statistical analyses
Data analysis was performed with statistical software (SPSS, version 17.0, IBM Corporation, Armonk, NY). Data were reported as mean ± standard deviation unless noted otherwise. Frequencies of patient and graft survival were calculated with the Kaplan-Meier method. Continuous variables with gaussian distributions were compared by t test. Categorical variables were compared with chi-square test. Statistical significance was defined by P < .05.

Results

Patient and organ survival
In the 71 patients who had liver transplant for primary sclerosing cholangitis, there were 11 patients who had late revision liver transplant, mostly because of biliary complications (Table 2). Death was most frequently caused by malignancy or organ failure (Table 2).

Survival without biliary complication, revision liver transplant, and death
There were 53 patients (75%) who survived without biliary complication at 5 years after transplant, and 32 patients (45%) at 10 years after transplant. There were 39 patients (55%) who had biliary complications, revision liver transplant, or death at a mean 12.1 years after transplant. Biliary interventions included endoscopic retrograde or percutaneous transhepatic cholangiography in 27 patients for diagnosis and treatment of nonanastomotic stenoses including ischemic type biliary lesions, and 9 patients had endoscopic retrograde cholangiography for anastomotic problems that were not classified as a biliary complication. In the 27 patients who had biliary interventions for nonanastomotic stenoses, there were 20 patients who were diagnosed with recurrent primary sclerosing cholangitis, usually with a combination of methods including endoscopic retrograde or percutaneous transhepatic cholangio-graphy, magnetic resonance cholangiography, and biopsy; in the other 7 patients who had a diagnosis of cholangitis, ischemic type biliary lesions, or ischemic biliary lesions, 5 patients died during follow-up and 2 patients were alive, were diagnosed with ischemic type biliary lesions or cholangitis by endoscopic retrograde cholangiography, and did not develop recurrent primary sclerosing cholangitis. In 1 patient, the diagnosis of recurrent primary sclerosing cholangitis was made on routine biopsy without previous biliary complication. Most patients had > 1 biliary intervention (total, 57 biliary interventions). There were 13 revision liver transplants performed in 11 patients (Table 2), and 9 patients were alive at follow-up. In 6 patients, the diagnosis of recurrent primary sclerosing cholangitis was confirmed in the explanted liver graft at revision transplant. There were 16 patients who died during follow-up and 39 patients who had a biliary complication, revision liver transplant, or death (Figure 4).

Inflammatory bowel disease
Most patients had inflammatory bowel disease, primarily ulcerative colitis (Table 2). Before liver transplant, 3 patients who had ulcerative colitis had undergone total colectomy (Table 2). After orthotopic liver transplant, no patient was newly diagnosed with ulcerative colitis, but 11 patients had ulcerative colitis that progressed and necessitated hospital admission for bowel surgery (6 patients) or steroid treatment (4 patients). After orthotopic liver transplant, 3 patients had colectomy (Table 2) and 4 patients had other bowel operations (closure of ileostomy, 3 patients; completion of ileoanal pouch anastomosis, 1 patient).

Risk factors for biliary complications
Male sex of transplant recipients was a significant risk factor for biliary complications, revision liver transplant, or death (Table 3). Mean time from liver transplant to development of biliary complications, revision liver transplant, or death was significantly greater for female than male patients (Table 3). There were no differences between patients who had or did not have biliary complications, revision liver transplant, or death for other variables evaluated, including donor or recipient age, cold ischemia time, donor sex, autoantibodies, transplant type, biliary anastomosis type, preservation injury grade, postoperative acute cellular rejection, immuno­suppressive regimen, or colectomy (Table 3). Most patients had ≥ 1 episode of acute cellular rejection that was treated with methylprednisolone bolus, but frequency of rejection was similar between groups that had or did not have biliary complications, revision liver transplant, or death (Table 3).

Human leukocyte antigen prevalence and matching
The prevalence of HLA-DR3, HLA-DR6, heterozygous DR3, DQ2 haplotype, and HLA-B8 was similar between patients who had or did not have biliary complications, revision liver transplant, or death (Table 4).

In the evaluation of mismatches between donor and recipient for HLA-A, HLA-B, or HLA-DR, the frequency of recipients with 0 or 1 mismatch compared with 2 mismatches for each locus was similar between the groups (not significant), and the frequency of mismatches of these loci did not affect complication-free survival. When HLA-A, HLA-B, and HLA-DR loci were grouped together, most patients had 5 to 6 mismatches at all 3 loci (Table 5). Mean time from transplant to complication was similar between patients who had 5 to 6 mismatches (114 mo), and patients who had 3 to 4 mismatches (97 mo; not significant). The proportion of patients with biliary complication, revision liver transplant, or death was similar between the mismatch groups (10 patients [53%] with 3 to 4 mismatches; 16 patients [42%] with 5 to 6 mismatches). The number of rejection episodes was similar between patients who had 3 to 4 mismatches (11 patients [52%]) and 5 to 6 mismatches (23 patients [64%]; not significant). Therefore, the presence and number of mismatches had no effect on biliary complications, revision liver transplant, and death or acute cellular rejection episodes in patients who had liver transplant for primary sclerosing cholangitis.

For HLA-C, most donor-recipient pairs (21 of 31 transplants) had mismatches on both C1 and C2 alleles (Table 5). Only 1 patient who had biliary complications, recurrent liver transplant, or death had no mismatches and 4 patients who had biliary complications, recurrent liver transplant, or death had 1 mismatch. Therefore, the number of mismatches of HLA-C alleles was similar in patients who had or did not have biliary complications, recurrent liver transplant, or death.

Recipients who had ulcerative colitis were mostly homozygous for the C1 allele (20 patients), occasionally heterozygous for C1 and C2 (6 patients), and rarely homozygous for C2 (1 patient). For the other 15 patients who had ulcerative colitis, no HLA-C typing was available.

In 20 recipients diagnosed with recurrent primary sclerosing cholangitis after liver transplant, 6 patients were homozygous for the C1 allele. In the 35 recipients who were treated for acute cellular rejection, HLA-C typing showed that 19 patients were homozygous for the C1 allele, 1 patient was homozygous for C2, and 5 patients were heterozygous. There were 6 patients who had acute cellular rejection who had 0 or 1 mismatch at the HLA-C locus, and donor typing showed 12 donors who were homozygous for C1 and 14 donors who were homozygous for C2. There was no effect of HLA-C type on the presence or absence of biliary complications, recurrent liver transplant, or death. None of the 11 patients who had revision liver transplant had 0 or 1 mismatch. In 5 patients who had revision liver transplant, grafts received were homozygous for C2. The presence of ≥ 1 C2 allele in the donor had no effect on development of biliary complications, recurrent liver transplant, or death.

Discussion

Long-term outcome after orthotopic liver transplant has improved during recent years because of improved surgical technique and immuno-suppressive therapy. The actuarial 10-year patient survival in the present series of 71 patients who had liver transplant for primary sclerosing cholangitis was 79% after exclusion of patients with known cholangiocarcinoma, and the 10-year organ survival was 68%. This is comparable to other published studies with a 10-year patient survival of 76%.¹²

Although patients receiving liver transplant for primary sclerosing cholangitis usually have good long-term survival, they have the risk of disease recurrence and other complications after liver transplant. The frequency of recurrent primary sclerosing cholangitis varies because of differences in duration of follow-up and protocols to detect biliary strictures between different studies.^2,7,30,31 The definition of recurrent primary sclerosing cholangitis usually is based on published criteria³ including biopsy and cholangiographic findings.^4,5 In selected cases, partial resection of liver graft tissue that has limited biliary injury may be possible to prevent complete loss of the transplanted liver and revision transplant.³² In addition, revision transplant and death were primary endpoints. Using this definition, the overall 10-year complication-free survival was 45%.

Risk factors for recurrent primary sclerosing cholangitis have been studied extensively and varied results have been reported. A previous study showed that male sex was associated with worse outcome.11 In the present study, a significantly worse outcome was observed in male transplant recipients; male recipients had significantly more biliary complications, revision liver transplant, or death, and the time from transplant to complication was significantly shorter for male recipients (Table 3). Another previous study showed sex mismatch between donor and recipient as a risk factor for disease recurrence.10 In the present patients, sex mismatch had no effect on survival without biliary complications.

The disease course before orthotopic liver transplant, such as a shorter and more aggressive disease course before liver transplant, had no significant effect on biliary complications after orthotopic liver transplant. Donor or recipient age, cold ischemia time and preservation injury, or type of transplant or biliary anastomosis did not cause any difference between patients who had or did not have biliary complications (Table 3).

Steroid-resistant rejection,^5,33 and treatment with muromonab-CD3 are risk factors for the recurrence of primary sclerosing cholangitis after orthotopic liver transplant. In the present patients, we found no effect of acute cellular rejection on recurrent primary sclerosing cholangitis, and the number of steroid-resistant episodes of rejection that necessitated antibody treatment was not different between the groups (Table 3). However, the overall incidence of acute cellular rejection was high, with 63% recipients having ≥ 1 rejection episode and 7 patients diagnosed with chronic rejection. Although 14 patients in our cohort with acute cellular rejection had received grafts from donors homozygous for the C2 allele, most recipients were homozygous for the C1 allele. In the 11 patients undergoing revision transplant, 5 patients had initially received donor grafts that were homozygous for C2. The presence of ≥ 1 C2 allele in grafts of 33 patients caused no significant effect on complication-free survival in the present patients. A previous study showed an effect of HLA-C on chronic rejection and graft loss.²⁶ The HLA-C alleles may be important as ligands for killer immuno-globulinlike receptors. These receptors are present on NK cells and some T lymphocytes and may affect cytotoxicity. The HLA-C2 allele causes stronger inhibition of NK cells than HLA-C1 alleles. The presence of ≥ 1 C2 allele in donors reduced the risk for chronic rejection, graft cirrhosis, and eventually graft loss in a previous study.²⁷

The effect of acute cellular rejection on recurrent primary sclerosing cholangitis may reflect the interaction between graft and host immune response and the possible effect of immunosuppression.³⁴ It is unknown whether current immunosuppression given to patients who have primary sclerosing cholangitis is inappropriate and ineffective or whether acute cellular rejection and steroid-resistant rejection may require different treatment options. At our institution, the immunosuppressive protocol varies. Approximately 50% patients received a protocol based on tacrolimus and 37% received a protocol that included azathioprine. No effect of immunosuppressive protocol on biliary complication-free survival was detected, and the immunologic stress in the present patients and high frequency of acute cellular rejection may be affected by other factors than the immunosuppressive protocol. Nevertheless, prospective studies are needed to evaluate immunosuppression, and these studies may improve the frequency of acute cellular rejection and outcome.

Most patients with primary sclerosing cholangitis also are diagnosed with inflammatory bowel disease, primarily ulcerative colitis, and bowel inflammation may affect liver graft and patient survival. There is controversy about the concept that colonic inflammation may be a risk factor for recurrent primary sclerosing cholangitis after orthotopic liver transplant. In the present patients, there was no effect of timing of colectomy or presence of an intact colon on the development of recurrent primary sclerosing cholangitis. Progression of ulcerative colitis was observed in 11 patients after liver transplant, including 4 patients treated with steroids, but no association with recurrent primary sclerosing cholangitis was demonstrated. One study suggested that total colectomy before orthotopic liver transplant may have a protective effect on disease-free survival in patients who have primary sclerosing cholangitis.¹⁴ This concept supports the hypothesis that a leak of bacterial toxins from the inflamed colon may cause recurrent primary sclerosing cholangitis.³⁵ On the other hand, the homing of gut mucosal memory lymphocytes to the liver may be the cause for primary³⁶ and recurrent primary sclerosing cholangitis because liver disease may develop even in the absence of active inflammation of the gut. Others have shown a negative effect of steroids, given for acute exacerbation of ulcerative colitis or as maintenance therapy, on recurrent primary sclerosing cholangitis and postulated that steroids mainly reflect ulcerative colitis activity and not graft dysfunction.¹² In the present study, neither acute cellular rejection, treated with steroids or muromonab-CD3, nor steroids for active ulcerative colitis affected biliary complication-free survival. Further study is required to evaluate the possible link between ulcerative colitis and primary sclerosing cholangitis and the effect of an intact colon at the time of transplant.

Many transplant recipients with ulcerative colitis are homozygous for the C1 allele. In the present study, 20 transplant recipients who had ulcerative colitis were homozygous for the C1 allele, 1 patient was homozygous for the C2 allele, and 6 patients were heterozygous. HLA-C typing of donors showed that 11 donors were homozygous for C1, 7 donors were homozygous for C2, and 7 donors were heterozygous. All grafts that were homozygous for C2 were transplanted to recipients homozygous for the C1 allele. Therefore, most present patients who had primary sclerosing cholangitis and ulcerative colitis carried the C1 allele, consistent with the hypothesis that inflammation of the liver is linked to aberrant homing of mucosal T cells from the colon.³⁷

Several human leukocyte antigen haplotypes have been associated with primary sclerosing cholangitis. The HLA-DR3 (HLA-DRB1*0301-DQA1*0501-DQB1*0201) and HLA-DR6 (HLA-DRB1*1301-DQA1*0103-DQB1*0603) may cause an increased risk of developing primary sclerosing cholangitis.³⁸ Furthermore, the heterozygous DR3, DQ2 haplotype is linked to an accelerated progression of primary sclerosing cholangitis.¹⁷ In patients negative for DR3, DQ2 the presence of the DR6 haplotype is linked to delayed disease progression. These findings have been confirmed by others who showed that additional microsatellite markers may increase the risk of developing primary sclerosing cholangitis in patients who have the DR6 haplotype.³⁹

In our patients, HLA-DR3 and HLA-DR6 had no effect on biliary complication-free survival. The DR3, DQ2-haplotype was equally distributed between the groups in the present study. Only 2 patients negative for DR3, DQ2 were typed positive for HLA-DR6, and both patients had biliary complications, in contrast with previously published results.³⁹ The HLA-B8 haplotype has been associated with the development of primary sclerosing cholangitis in patients with ulcerative colitis.¹⁶ The extended B8, DR3 haplotype including particular MICA and MICB alleles are associated with an elevated risk for developing primary sclerosing cholangitis.¹⁷ In accordance with this observation, we detected a high prevalence of the B8 haplotype in our transplant recipients (52%), but there was no statistically significant difference between the groups. The combined B8, DR3 haplotype was identified with low prevalence in both recipients and donors, but recipients and patients with donor organs positive for B8, DR3 were exclusively found in the group with biliary complications. The 1 patient positive for HLA-B8, DR3 who received an organ with the same genetic composition experienced 2 early episodes of acute cellular rejection but died within 3 months because of cardiac failure. Although the numbers of patients were too small for statistical validation, the haplotype distribution in our patients was typical for patients with primary sclerosing cholangitis, including a high incidence of B8 and DR3, DQ2. Furthermore, the B8, DR3 haplotype was only detected in patients experiencing recurrent primary sclerosing cholangitis after orthotopic liver transplant. Only 1 human leukocyte antigen haplotype (DR3) may be related to recurrent primary sclerosing cholangitis after orthotopic liver transplant, and DR3, DQ2 or DR6 may not be linked to recurrent primary sclerosing cholangitis.²² The DR8 haplotype was not present in our cohort.

There is controversy about the effect of human leukocyte antigen matching on outcome after orthotopic liver transplant in patients who have primary sclerosing cholangitis. In the present patients, the distribution of patients with 0 or 1 compared with 2 mismatches at individual loci was equal for those with or without biliary complication, recurrent liver transplant, or death. For all 3 loci, none of the patients displayed < 3 mismatches. Although approximately twice as many patients displayed 5 or 6 mismatches (complete disparity between donor and recipient), mean time to a biliary complication was similar in these patients and patients who had 3 or 4 mismatches. The proportion of patients who had biliary complications also was evenly distributed. The number of rejection episodes was similar between patients who had 3 to 4 or 5 to 6 mismatches. None of the present patients had complete compatibility between graft and recipient, but the total number of mismatches had no effect on time to complication or outcome. Although a previous study found no effect of human leukocyte antigen mismatches at any locus on patient outcome, another study showed that mismatch between donor and recipient at the A locus significantly increased disease recurrence, and mismatch at the DR locus conferred decreased risk for recurrent primary sclerosing cholangitis.^12,27

Another study showed significantly decreased graft survival in the presence of 0 or 1 mismatch compared with 2 HLA-DR mismatches, with decreased risk for developing recurrent primary sclerosing cholangitis with 2 HLA-DR mismatches.²⁶ It has been hypothesized that human leukocyte antigen mismatching may act beneficially by decreasing the effects of immunologic mechanisms associated with disease recurrence in patients transplanted for autoimmune diseases.⁴⁰ The human leukocyte antigen mismatching at all loci positively affects patients transplanted for autoimmune hepatitis,⁴¹ and a negative effect of DR mismatching has been noted on graft survival in patients with autoimmune hepatitis.⁴² Living-related liver transplant may be associated with an increased risk of developing recurrent primary sclerosing cholangitis, in support of the hypothesis that human leukocyte antigen mismatching may have a positive effect on disease recurrence.^43,44 Although living donor transplant may have advantages in timing and neoadjuvant protocols in patients who have cholangiocellular carcinoma, there may be an increased risk for developing recurrent primary sclerosing cholangitis. In contrast, mismatching may be associated with increased risk of graft rejection and allograft dysfunction, especially in patients who have liver transplant for other liver diseases, and this may outweigh the positive effects of mismatching on autoimmune mechanisms.

In conclusion, the present study analyzed risk factors for biliary complication-free survival after liver transplant. Genetic predisposition seems to be an important contributor to biliary complications and recurrent primary sclerosing cholangitis after liver transplant. Further study of the effect of human leukocyte antigen typing and matching on outcomes in more patients may be helpful. The effect of immunosuppression and genetic specificities may be associated with outcome and favor approaches such as individually-tailored immunosuppressive protocols or organ distribution that is tailored to the human leukocyte antigen profiles of donor and recipient.

References:

1. Hong JC, Yersiz H, Farmer DG, et al. Longterm outcomes for whole and segmental liver grafts in adult and pediatric liver transplant recipients: a 10-year comparative analysis of 2,988 cases. J Am Coll Surg. 2009;208(5):682-689; discusion 689-91.
   CrossRef - PubMed
2. Gautam M, Cheruvattath R, Balan V. Recurrence of autoimmune liver disease after liver transplantation: a systematic review. Liver Transpl. 2006;12(12):1813-1824.
   CrossRef - PubMed
3. Graziadei IW, Wiesner RH, Batts KP, et al. Recurrence of primary sclerosing cholangitis following liver transplantation. Hepatology. 1999;29(4):1050-1056.
   CrossRef - PubMed
4. MacCarty RL, LaRusso NF, Wiesner RH, Ludwig J. Primary sclerosing cholangitis: findings on cholangiography and pancreatography. Radiology. 1983;149(1):39-44.
   PubMed
5. Brandsaeter B, Schrumpf E, Bentdal O, et al. Recurrent primary sclerosing cholangitis after liver transplantation: a magnetic resonance cholangiography study with analyses of predictive factors. Liver Transpl. 2005;11(11):1361-1369.
   CrossRef - PubMed
6. Stange BJ, Glanemann M, Nuessler NC, Settmacher U, Steinmüller T, Neuhaus P. Hepatic artery thrombosis after adult liver transplantation. Liver Transpl. 2003;9(6):612-620.
   CrossRef - PubMed
7. Ren J, Zheng BW, Wang P, et al. Revealing impaired blood supply to the bile ducts on contrast-enhanced ultrasound: a novel diagnosis method to ischemic-type biliary lesions after orthotropic liver transplantation. Ultrasound Med Biol. 2013;39(5):753-760.
   CrossRef - PubMed
8. Schmitz V, Neumann UP, Puhl G, Tran ZV, Neuhaus P, Langrehr JM. Surgical complications and long-term outcome of different biliary reconstructions in liver transplantation for primary sclerosing cholangitis-choledochoduodenostomy versus choledochojejunostomy. Am J Transplant. 2006;6(2):379-385.
   CrossRef - PubMed
9. Zimmerman MA, Baker T, Goodrich NP, et al. Development, management, and resolution of biliary complications after living and deceased donor liver transplantation: a report from the adult-to-adult living donor liver transplantation cohort study consortium. Liver Transpl. 2013;19(3):259-267.
   CrossRef - PubMed
10. Khettry U, Keaveny A, Goldar-Najafi A, et al. Liver transplantation for primary sclerosing cholangitis: a long-term clinicopathologic study. Hum Pathol. 2003;34(11):1127-1136.
    CrossRef - PubMed
11. Vera A, Moledina S, Gunson B, et al. Risk factors for recurrence of primary sclerosing cholangitis of liver allograft. Lancet. 2002;360(9349):1943-1944.
    CrossRef - PubMed
12. Cholongitas E, Shusang V, Papatheodoridis GV, et al. Risk factors for recurrence of primary sclerosing cholangitis after liver transplantation. Liver Transpl. 2008;14(2):138-143.
    CrossRef - PubMed
13. Verdonk RC, Dijkstra G, Haagsma EB, et al. Inflammatory bowel disease after liver transplantation: risk factors for recurrence and de novo disease. Am J Transplant. 2006;6(6):1422-1429.
    CrossRef - PubMed
14. Alabraba E, Nightingale P, Gunson B, et al. A re-evaluation of the risk factors for the recurrence of primary sclerosing cholangitis in liver allografts. Liver Transpl. 2009;15(3):330-340.
    CrossRef - PubMed
15. Campsen J, Zimmerman MA, Trotter JF, et al. Clinically recurrent primary sclerosing cholangitis following liver transplantation: a time course. Liver Transpl. 2008;14(2):181-185.
    CrossRef - PubMed
16. Chapman RW, Varghese Z, Gaul R, Patel G, Kokinon N, Sherlock S. Association of primary sclerosing cholangitis with HLA-B8. Gut. 1983;24(1):38-41.
    CrossRef - PubMed
17. Boberg KM, Spurkland A, Rocca G, et al. The HLA-DR3,DQ2 heterozygous genotype is associated with an accelerated progression of primary sclerosing cholangitis. Scand J Gastroenterol. 2001;36(8):886-890.
    CrossRef - PubMed
18. Hov JR, Lleo A, Selmi C, et al. Genetic associations in Italian primary sclerosing cholangitis: heterogeneity across Europe defines a critical role for HLA-C. J Hepatol. 2010;52(5):712-717..
    CrossRef - PubMed
19. Mandelboim O, Reyburn HT, Sheu EG, et al. The binding site of NK receptors on HLA-C molecules. Immunity. 1997;6(3):341-350.
    CrossRef - PubMed
20. Radaev S, Sun PD. Structure and function of natural killer cell surface receptors. Annu Rev Biophys Biomol Struct. 2003;32:93-114.
    CrossRef - PubMed
21. Khakoo SI, Thio CL, Martin MP, et al. HLA and NK cell inhibitory receptor genes in resolving hepatitis C virus infection. Science. 2004;305(5685):872-874.
    CrossRef - PubMed
22. Alexander J, Lord JD, Yeh MM, Cuevas C, Bakthavatsalam R, Kowdley KV. Risk factors for recurrence of primary sclerosing cholangitis after liver transplantation. Liver Transpl. 2008;14(2):245-251.
    CrossRef - PubMed
23. Manousou P, Arvaniti V, Tsochatzis E, et al. Primary biliary cirrhosis after liver transplantation: influence of immunosuppression and human leukocyte antigen locus disparity. Liver Transpl. 2010;16(1):64-73.
    CrossRef - PubMed
24. Balan V, Ruppert K, Demetris AJ, et al. Long-term outcome of human leukocyte antigen mismatching in liver transplantation: results of the National Institute of Diabetes and Digestive and Kidney Diseases Liver Transplantation Database. Hepatology. 2008;48(3):878-888..
    CrossRef - PubMed
25. Neumann UP, Guckelberger O, Langrehr JM, et al. Impact of human leukocyte antigen matching in liver transplantation. Transplantation. 2003;75(1):132-137.
    CrossRef - PubMed
26. Hanvesakul R, Spencer N, Cook M, et al. Donor HLA-C genotype has a profound impact on the clinical outcome following liver transplantation. Am J Transplant. 2008;8(9):1931-1941.
    CrossRef - PubMed
27. Tran TH, Middleton D, Döhler B, et al. Reassessing the impact of donor HLA-C genotype on long-term liver transplant survival. Am J Transplant. 2009;9(7):1674-1678.
    CrossRef - PubMed
28. Bowlus CL, Li CS, Karlsen TH, Lie BA, Selmi C. Primary sclerosing cholangitis in genetically diverse populations listed for liver transplantation: unique clinical and human leukocyte antigen associations. Liver Transpl. 2010;16(11):1324-1330.
    CrossRef - PubMed
29. [No authors listed] Banff schema for grading liver allograft rejection: an international consensus document. Hepatology. 1997;25(3):658-663.
    CrossRef - PubMed
30. Weismüller TJ, Wedemeyer J, Kubicka S, Strassburg CP, Manns MP. The challenges in primary sclerosing cholangitis--aetiopathogenesis, autoimmunity, management and malignancy. J Hepatol. 2008;48 Suppl 1:S38-57.
    CrossRef - PubMed
31. Lerut J, Demetris AJ, Stieber AC, et al. Intrahepatic bile duct strictures after human orthotopic liver transplantation. Recurrence of primary sclerosing cholangitis or unusual presentation of allograft rejection? Transpl Int. 1988;1(3):127-30.
    CrossRef - PubMed
32. Guckelberger O, Stange B, Glanemann M, et al. Hepatic resection in liver transplant recipients: single center experience and review of the literature. Am J Transplant. 2005;5(10):2403-2409.
    CrossRef - PubMed
33. Kugelmas M, Spiegelman P, Osgood MJ, et al. Different immunosuppressive regimens and recurrence of primary sclerosing cholangitis after liver transplantation. Liver Transpl. 2003;9(7):727-732.
    CrossRef - PubMed
34. Bjøro K, Brandsaeter B, Foss A, Schrumpf E. Liver transplantation in primary sclerosing cholangitis. Semin Liver Dis. 2006;26(1):69-79.
    CrossRef - PubMed
35. Cullen S, Chapman R. Aetiopathogenesis of primary sclerosing cholangitis. Best Pract Res Clin Gastroenterol. 2001 Aug;15(4):577-89.
    CrossRef - PubMed
36. Grant AJ, Lalor PF, Salmi M, Jalkanen S, Adams DH. Homing of mucosal lymphocytes to the liver in the pathogenesis of hepatic complications of inflammatory bowel disease. Lancet. 2002;359(9301):150-7.
    CrossRef - PubMed
37. Adams DH, Eksteen B. Aberrant homing of mucosal T cells and extra-intestinal manifestations of inflammatory bowel disease. Nat Rev Immunol. 2006 Mar;6(3):244-51.
    CrossRef - PubMed
38. Spurkland A, Saarinen S, Boberg KM, et al. HLA class II haplotypes in primary sclerosing cholangitis patients from five European populations. Tissue Antigens. 1999;53(5):459-469.
    CrossRef - PubMed
39. Wiencke K, Karlsen TH, Boberg KM, et al. Primary sclerosingcholangitis is associated with extended HLA-DR3 and HLA-DR6 haplotypes. Tissue Antigens. 2007;69(2):161-169.
    CrossRef - PubMed
40. Markus BH, Duquesnoy RJ, Gordon RD, Fung JJ, Vanek M, Klintmalm G, Bryan C, Van Thiel D, Starzl TE. Histocompatibility and liver transplant outcome. Does HLA exert a dualistic effect? Transplantation. 1988 Sep;46(3):372-7.
    PubMed
41. Doran TJ, Geczy AF, Painter D, McCaughan G, Sheil AG, Süsal C, Opelz G. A large, single center investigation of the immunogenetic factors affecting liver transplantation. Transplantation. 2000 Apr 15;69(7):1491-8.
    CrossRef - PubMed
42. Opelz G. Preliminary analysis of HLA matching in pancreas and liver transplantation. Collaborative Transplant Study. Transplant Proc. 1993 Aug;25(4):2652-2653.
    PubMed
43. Kashyap R, Mantry P, Sharma R, et al. Comparative analysis of outcomes in living and deceased donor liver transplants for primary sclerosing cholangitis. J Gastrointest Surg. 2009;13(8):1480-1486.
    CrossRef - PubMed
44. Egawa H, Taira K, Teramukai S, et al. Risk factors for recurrence of primary sclerosing cholangitis after living donor liver transplantation: a single center experience. Dig Dis Sci. 2009;54(6):1347-1354.
    CrossRef - PubMed