Post-liver transplantation de novo hepatitis with overlap features

Plasma Cell Infiltrate in Liver Allograft Biopsy: Clinical and Histological Implications

Introduction:

The relevance of plasma cells in the allograft liver is of utmost importance and objective assessment of these infiltrates and correlation with other ancillary findings needs to be evaluated.

Materials and Methods:

Three hundred and sixty-eight graft liver biopsies received in the department from 2012 to 2022 and 115 allograft liver biopsies with histopathological diagnosis of rejection were selected. Based on plasma cells percentage in the portal tracts, the biopsies were divided into three groups: Group 1 showing not more than an occasional plasma cell, Group 2 showing <10% plasma cells, and Group 3 showing >10% plasma cells. Rejection activity index (RAI), portal/lobular inflammation, interface activity, subendothelial inflammation (portal and central vein), duct damage/loss, presence of cholestasis, apoptosis, perivenulitis, necrosis, rosette along with serial liver function tests (LFTs), and patient status at 1 year of follow-up were recorded and compared between the groups.

Results:

Plasma cell infiltrates were observed in 52.6% of the specimens, with the mean percentage of plasma cells in the infiltrates being 4.9. Increased plasma cell infiltrates were associated with higher RAI scores, marked duct damage, marked portal and central vein endotheliitis, marked portal inflammation, and presence of interface activity. Higher levels of transaminitis were recorded at the time of biopsy, but no significant association was observed in the fall of serial LFTs over a 2-week period with the presence of plasma cells.

Conclusion:

Identifying plasma cell infiltrates in liver allografts can serve as a clue toward increased severity of rejection in liver allograft biopsies. Further studies with emphasis on correlation with the clinical outcome and response to treatment are needed to validate its utility as an objective tool.

De novo autoimmune hepatitis in liver transplant: State-of-the-art review

In the two past decades, a number of communications, case-control studies, and retrospective reports have appeared in the literature with concerns about the development of a complex set of clinical, laboratory and histological characteristics of a liver graft dysfunction that is compatible with autoimmune hepatitis. The de novo prefix was added to distinguish this entity from a pre-transplant primary autoimmune hepatitis, but the globally accepted criteria for the diagnosis of autoimmune hepatitis have been adopted in the diagnostic algorithm. Indeed, de novo autoimmune hepatitis is characterized by the typical liver necro-inflammation that is rich in plasma cells, the presence of interface hepatitis and the consequent laboratory findings of elevations in liver enzymes, increases in serum gamma globulin and the appearance of non-organ specific auto-antibodies. Still, the overall features of de novo autoimmune hepatitis appear not to be attributable to a univocal patho-physiological pathway because they can develop in the patients who have undergone liver transplantation due to different etiologies. Specifically, in subjects with hepatitis C virus recurrence, an interferon-containing antiviral treatment has been indicated as a potential inception of immune system derangement. Herein, we attempt to review the currently available knowledge about de novo liver autoimmunity and its clinical management.

Current and future treatments of autoimmune hepatitis

Corticosteroid therapy induces clinical, laboratory and histological improvements in 80% of patients with autoimmune hepatitis. Prednisone, alone or at a lower dose in combination with azathioprine, increases the 20-year life expectancy to 80% and prevents or reduces hepatic fibrosis in 79% of patients. The combination regimen is preferred and treatment should be considered in all patients with active disease. The duration of therapy is finite and the medication should be discontinued after resolution of all manifestations of inflammatory activity, including the histological changes. Relapse after drug withdrawal occurs in 50-79% of patients, and it should be treated with long-term azathioprine (2 mg/kg daily). Salvage therapies for individuals intolerant of or refractory to the conventional regimens include high-dose corticosteroids, with or without high-dose azathioprine, 6-mercaptopurine, mycophenolate mofetil, tacrolimus or ciclosporin. Liver transplantation should be considered in patients with hepatic failure unresponsive to corticosteroid treatment, decompensated cirrhosis with a Model for End-Stage Liver Disease score of at least 15 points, or hepatocellular carcinoma that meets transplantation criteria. Autoimmune hepatitis recurs after transplantation in at least 17% of patients, and it typically improves after adjustments in the immunosuppressive regimen. Future therapies are likely to include mesenchymal stem cell transplantation, adoptive transfer of T regulatory cells, and cytokine manipulation. The emergence of new treatments will require the development of a collaborative network of clinical and basic investigators, as the complexity and specificity of current management problems require solutions that exceed the capabilities of single institutions.

De novo autoimmune hepatitis after living donor liver transplantation is unlikely to be related to immunoglobulin subtype 4-related immune disease

BACKGROUND AND AIM

Recently, we reported that immunoglobulin subtype 4 (IgG4) is involved in autoimmune hepatobiliary diseases, such as autoimmune hepatitis, sclerosing cholangitis, and pancreatitis. However, the association of IgG4 with autoimmune hepatic disease after living donor liver transplantation (LDLT) has not been investigated.

METHODS

Of the 72 LDLT recipients, four patients (5.6%) were suspected of having autoimmune-related hepatic disease after LDLT. The diagnosis was made based on a histological diagnosis following an examination of a biopsy liver specimen in three cases, while in one case a pemphigoid appeared in the flank with liver fibrosis of unknown cause. Human leukocyte antigen (HLA) mismatches were 3, 2, 2, and 2, respectively. The serum level of IgG4 in the patients was measured, and IgG4 immunohistochemical staining in the liver biopsy specimens was also performed.

RESULTS

In all cases, steroid pulse therapy or recycle treatment and subsequent increased steroid dose as well as additional azathioprine or mycophenolate mofetil were effective. While a few positive-stained cells for IgG4 were observed in the liver of one case, negative staining for IgG4 was observed in the other cases. All serum subclasses of IgG4 were within normal limits.

CONCLUSION

In our series of LDLT, IgG4-related immune disorder is unlikely to be involved in post-transplant, autoimmune-related liver disease.

Posttransplant plasma cell hepatitis (de novo autoimmune hepatitis) is a variant of rejection and may lead to a negative outcome in patients with hepatitis C virus

De novo autoimmune hepatitis has been described in both pediatric and adult liver transplantation (LT) recipients. Studies of small numbers of patients have proposed it to be an alloimmune hepatitis or form of chronic rejection. We have recently noted an increasing number of patients with post-LT recurrent hepatitis C virus (HCV) developing this, with an apparent negative impact on outcome and survival. We term this entity posttransplant plasma cell hepatitis (PCH). A search of our institution's pathology database was performed with the terms "plasma cell(s)," "lymphoplasmacytic infiltrate," and "liver allograft." A histological scoring system was devised to more reliably diagnose PCH in the setting of recurrent HCV. Thirty-eight patients were identified, and their clinical data were analyzed. Sixty percent had a negative outcome as defined by the development of cirrhosis, need for retransplantation, or death. Eighty-two percent had recent lowering of immunosuppression or subtherapeutic calcineurin inhibitor levels; 58% developed PCH within 2 years post-LT. Histologic resolution of PCH was associated with good outcome (P < 0.001). Patients not receiving treatment had a negative outcome (P = 0.007) as did patients receiving corticosteroids as therapy (P = 0.02). Persistence (P = 0.007) or recurrence of PCH was associated with negative outcome. In conclusion, PCH is a histologic variant of rejection. On liver biopsy, PCH can at times be difficult to diagnose, and the use of a standardized scoring system is recommended to differentiate it from other forms of allograft dysfunction. Treatment by optimization of immunosuppression without the use of corticosteroids appears effective. The development of PCH in the setting of recurrent HCV is a negative prognostic factor for patient outcome and allograft failure.

Autoimmune liver disease and rheumatic manifestations

PURPOSE OF REVIEW

To review studies that clarify the rheumatic manifestations of autoimmune hepatitis, elucidate shared pathogenic pathways, and encourage innovative site-specific therapies.

RECENT FINDINGS

Autoimmune hepatitis has clinical manifestations, serological markers, pathogenic mechanisms, genetic predispositions, and therapies similar to the rheumatic diseases. The rheumatic manifestations may mask the underlying liver disease and vice versa. Variations in clinical phenotype and outcome for the autoimmune liver diseases may reflect host-specific and region-specific factors, and defects in counter-regulatory suppressor functions by regulatory T cells may facilitate cell-mediated cytotoxicity and autoreactivity. Mixed syndromes with hallmark features of one disease in another probably reflect a genetic predisposition for immune expression that is shared among the diseases. Mycophenolate mofetil, budesonide, rapamycin, and 6-thioguanine are promising treatments, and de-novo autoimmune hepatitis after liver transplantation suggests that the calcineurin inhibitors may have paradoxical effects on self-tolerance.

SUMMARY

Clinical phenotypes of autoimmune hepatitis commonly include rheumatic manifestations that can mask the liver disease. Defects in counter-regulatory functions enhance cell-mediated cytotoxicity, and pharmacological interventions that promise site-specific actions affecting immunocyte differentiation and proliferation are feasible.

Autoimmune liver disease

PURPOSE OF REVIEW

To review studies that improve the diagnosis and treatment of autoimmune hepatitis and presage new drug and molecular site-specific interventions.

RECENT FINDINGS

Autoimmune hepatitis can present as acute or chronic hepatitis and as allograft dysfunction after liver transplantation. Elderly patients have an indolent but aggressive disease that responds well to corticosteroid therapy, and human leukocyte antigen DR4 characterizes this population. Geographic and ethnic factors influence clinical phenotype and behavior, and defects in T-regulatory cells may enhance cell-mediated cytotoxicity. Treatment response is the best index of prognosis, and normalization of serum aminotransferase abnormalities prevents disease progression. Mycophenolate mofetil, budesonide, rapamycin, and 6-thioguanine have been effective in small clinical experiences. De-novo autoimmune hepatitis can occur in adults and children after liver transplantation, and rapamycin may be an effective treatment.

SUMMARY

Autoimmune hepatitis has a global distribution and diverse clinical manifestations. Phenotypes are affected by regional and ethnic factors which may provide clues to the etiologic agents. Defects in counter-regulatory functions enhance cell-mediated cytotoxicity, and interventions that promise site-specific actions affecting immunocyte differentiation and proliferation are now feasible. Autoimmune hepatitis must be considered in all patients with acute and chronic hepatitis and in all cases of allograft dysfunction after liver transplantation.