Humoral immune mechanism of liver injury in giant cell hepatitis with autoimmune hemolytic anemia

Research progress on the roles of complement in liver injury

The complement system is crucial for maintaining immunological homeostasis in the liver, playing a significant role in both innate and adaptive immune responses. Dysregulation of this system is closely linked to the pathogenesis of various liver diseases. Modulating the complement system can affect the progression of these conditions. To provide insights into treating liver injury by targeting the regulation of the complement system, we conducted a comprehensive search of major biomedical databases, including MEDLINE, PubMed, EMBASE, and Web of Science, to identify articles on complement and liver injury and reviewed the functions and mechanisms of the complement system in liver injury.

Giant cell hepatitis associated with autoimmune hemolytic anemia: More evidence for B-cell depletion therapy for a rare immune mediated disease of infancy

Giant cell hepatitis associated with autoimmune hemolytic anemia (GCH-AHA) is a rare but severe disease of infancy defined by an acute liver injury, histologically characterized by a widespread giant cell transformation and by an autoimmune hemolysis. GCH-AHA is thought to be immune-mediated being however a distinct entity from juvenile autoimmune hepatitis. In particular, GCH-AHA displays a less favorable response to conventional immunosuppressive treatment compared to classical juvenile autoimmune hepatitis, carrying a higher risk of mortality. In fact, since his first description, conventional therapy with prednisone with azathioprine has been used as first line treatment, however with frequent relapses during tapering, as well as severe side effects related to its prolonged use at high doses in early age. Due to the frequent occurrence of relapse, several immunosuppressive drugs have been tried as second line therapy with doubtful success. In case of severe liver dysfunction and/or severe anemia, transitory remission has been achieved with intravenous immunoglobulins administration, however with temporary response. B-cell depletion treatment, mostly with chimeric anti-CD20 monoclonal antibody (rituximab; RTX) has been used since 2004 with encouraging results mostly in refractory cases as second-line therapy. In this issue, the report of a series of 20 children with GCH-AHA from Shanghai, China, confirms the previous treatment experiences of a greater efficacy in obtaining complete remission of RTX or RTX treatment regimens compared to conventional regimens, with a good safety. To date, published experience with this rare disease suggests that RTX should be considered the cornerstone of treatment for complicated or relapsing cases of GCH-AHA and given the increasing evidence on its efficacy and safety, RTX might be even an acceptable option as first line therapy beside conventional treatment, to drastically reduce the cumulative steroids exposure and its side effects.

Efficacy of rituximab-containing regimens used as first-line and rescue therapy for giant cell hepatitis with autoimmune hemolytic anemia a retrospective study

OBJECTIVE

To evaluate the efficacy of rituximab (RTX)-containing therapy as first-line as well as rescue treatment for giant cell hepatitis with autoimmune hemolytic anemia (GCH-AHA).

METHODS

This retrospective study recruited patients diagnosed with GCH-AHA and treated with conventional immunosuppressor regimens consisting of prednisone or RTX-containing regimes consisting of RTX and prednisone, with or without another immunosuppressor. The primary outcomes were the complete remission (CR) rate and time-period required for CR. The secondary outcomes included relapses and adverse events.

RESULTS

Twenty patients (8 females and 12 males; age range 1-26 months), 15 receiving conventional regimens and 5 receiving RTX-containing regimens, were included. The CR rates were 73.3 % (11/15) and 100 % (5/5) in the conventional and RTX-containing groups, respectively. The time-period required for CR was significantly shorter in the RTX-containing group than in the conventional group (6 (3-8) versus 14 (5-25) months, P = 0.015). Relapses occurred in 30.8 % (4/13) of patients in the conventional group; all achieved CR after adding RTX. Relapses occurred in 40.0 % (2/5) of patients in the RTX-containing group; both achieved CR after adding intravenous immune globulins or tacrolimus. Transient low immunoglobulin and infections were recorded in both groups. Treatment withdrawal was achieved in 73.3 % (11/15) and 60.0 % (3/5) of patients receiving conventional and RTX-containing regimens after 36 (2-101) and 22 (4-41) months, respectively. Two patients in conventional group died of disease progression and infection.

CONCLUSIONS

RTX-containing first-line therapy achieves CR of GCH-AHA more quickly than the conventional therapy. RTX is efficacious when added to rescue therapy.

Postinfantile Giant Cell Hepatitis in Native and Allograft Livers: A Multi-Institutional Clinicopathologic Study of 70 Cases

Postinfantile giant cell hepatitis (PIGCH) is a rare hepatitis pattern in adults with variable etiologies and clinical outcomes. We conducted a multi-institutional retrospective study to define the clinicopathologic characteristics of patients with PIGCH. A total of 70 PIGCH cases were identified and reviewed for pathological features, including fibrosis, cholestasis, inflammation, steatosis, necrosis, and apoptosis, as well as the distribution of giant cells and the maximum number of giant cells per high-power field. Demographic and clinical data, including age, sex, laboratory results, etiologies, and follow-up results, were recorded. Among the 70 cases, 40% (28/70) were associated with autoimmune liver diseases, followed by 9 (13%) with unknown etiology, 8 (11%) with viral infection, 5 (7%) with medications, 5 with combined etiologies, and 4 (6%) with malignancies (mostly chronic lymphocytic leukemia). Notably, another 16% were de novo PIGCH in liver allografts, most of which occurred after a rejection event. During follow-up, 26 (37%) patients died of the disease and 44 (63%) were alive. Deceased patients were characterized by older age (mean age, 54.9 vs 45.5 years; P = .02), higher alkaline phosphatase level (mean value, 253.3U/L vs 166.3 U/L; P = .03), higher fibrosis stage (stage 3-4 vs stage 0-2, 57.7% vs 29.6%; P = .03), being more likely to have de novo PIGCH after transplantation (23.1% vs 11.4%; P = .04), and being less likely to have primary autoimmune liver disease etiology (26.9% vs 47.7%; P = .04). These results indicate that PIGCH is a rare pattern of liver injury associated with different etiologies and variable clinical outcomes. Autoimmune liver disease with PIGCH is associated with better survival, whereas de novo PIGCH in allografts is associated with poorer survival. Older age, higher alkaline phosphatase level, and advanced fibrosis are adverse prognostic factors.

Hemolysis in Early Infancy: Still a Cause of Cholestatic Neonatal Giant Cell Hepatitis

Before the prophylactic use of anti-D antibodies in pregnancy, hemolytic anemia of the newborn was the most common cause of hyperbilirubinemia. Nowadays, given the rarity of hemolytic anemia of the newborn, hepatobiliary abnormalities, perinatal infections, and metabolic disorders have become the most common conditions in the differential diagnosis of neonatal cholestasis. Here, we report 3 instances of cholestatic giant cell hepatitis in 3 infants who had Coombs' positive hemolysis due to ABO incompatibility in 1, Rh incompatibility in another, and combined ABO and Rh incompatibility in the third. Although rare, cholestatic neonatal giant cell hepatitis associated with hemolysis still needs to be considered in patients with neonatal cholestasis. A marked elevation of aspartate aminotransferase over alanine aminotransferase can be a helpful clue to an early diagnosis.

Infantile giant cell hepatitis with autoimmune hemolytic anemia

Giant cell hepatitis (GCH) is characterized by large and multinucleated (syncytial) hepatocytes in the context of liver inflammation. Infantile GCH is typically associated with autoimmune hemolytic anemia in the absence of any other systemic or organ-specific autoimmune comorbidity. The etiology is unknown; concomitant viral infections (as potential trigger factors) have been identified in a few patients. The pathogenesis reportedly relies upon immune-mediated/ autoimmune mechanisms. This condition should be considered in any infant developing Coombs-positive anemia; indeed, anemia usually precedes the development of hepatitis. The clinical course is usually aggressive without the appropriate immunosuppressive therapy, which may include steroids, conventional immunosuppressors (e.g., azathioprine and cyclophosphamide as first-line treatments), intravenous immunoglobulin, and biologics (rituximab). Improvements in medical management (including the availability of rituximab) have significantly reduced the mortality of this condition in the last decade.

Giant cell hepatitis associated with autoimmune hemolytic anemia: an update

Giant cell hepatitis associated with autoimmune hemolytic anemia (GCH-AHA) is a rare and severe disease characterized by autoimmune hemolysis associated with acute liver injury, histologically defined by widespread giant cell transformation. It occurs after the neonatal period, most commonly in the first year of life and uniquely affects pediatric patients. It is still poorly understood and likely underdiagnosed, although in recent years there have been advances in the understanding of its pathogenesis and the liver injury is now hypothesized to be secondary to a humoral immune mechanism. Although no laboratory test specific for the diagnosis currently exists, given its severity, it is fundamental to rule out GCH-AHA when evaluating a patient in the first year of life presenting with AHA and/or with acute liver disease of unknown etiology. While GCH-AHA is progressive in nature as other autoimmune liver disorders, it differs significantly from juvenile autoimmune hepatitis (JAIH) in that a cure can be achieved after several years of intensive treatment in a portion of patients. Conventional first line therapy consist of prednisone/prednisolone combined with azathioprine, however, several immunosuppressive drugs, commonly used in the treatment of JAIH have been tried as second line therapy, including cyclosporine, cyclophosphamide, mycophenolate mofetil, 6-mercaptopurine, calcineurin inhibitors, and sirolimus. Intravenous immunoglobulins have also been used in cases of severe liver dysfunction and/or severe anemia allowing for transitory remission. More recently treatment with B-cell depletion has been attempted in some patients and encouraging results have been reported in refractory cases. Although what constitutes optimal treatment has yet to be determined, the recent progress in the understanding of the pathogenetic mechanisms of GCH-AHA have made positive strides, cautiously pointing toward a hopeful prognosis for some of these patients.

Autoimmune Hemolytic Anemia in the Pediatric Setting

Autoimmune hemolytic anemia (AIHA) is a rare disease in children, presenting with variable severity. Most commonly, warm-reactive IgG antibodies bind erythrocytes at 37 °C and induce opsonization and phagocytosis mainly by the splenic macrophages, causing warm AIHA (w-AIHA). Post-infectious cold-reactive antibodies can also lead to hemolysis following the patient’s exposure to cold temperatures, causing cold agglutinin syndrome (CAS) due to IgM autoantibodies, or paroxysmal cold hemoglobinuria (PCH) due to atypical IgG autoantibodies which bind their target RBC antigen and fix complement at 4 °C. Cold-reactive antibodies mainly induce intravascular hemolysis after complement activation. Direct antiglobulin test (DAT) is the gold standard for AIHA diagnosis; however, DAT negative results are seen in up to 11% of warm AIHA, highlighting the need to pursue further evaluation in cases with a phenotype compatible with immune-mediated hemolytic anemia despite negative DAT. Prompt supportive care, initiation of treatment with steroids for w-AIHA, and transfusion if necessary for symptomatic or fast-evolving anemia is crucial for a positive outcome. w-AIHA in children is often secondary to underlying immune dysregulation syndromes and thus, screening for such disorders is recommended at presentation, before initiating treatment with immunosuppressants, to determine prognosis and optimize long-term management potentially with novel targeted medications.

The role of complement activation in autoimmune liver disease

INTRODUCTION

The complement system, an essential part of the innate immune system, is involved in various autoimmune diseases. Activation of the complement system by autoantibodies results in immune activation and tissue damage. At the moment little is known about the role of the complement system in autoimmune liver disease, including primary biliary cholangitis (PBC), primary sclerosing cholangitis (PSC) and autoimmune hepatitis (AIH). Since inhibition of the complement system is currently being tested in several autoimmune diseases as a therapeutic option, its role in autoimmune liver disease requires further clarification.

METHODS

A review of the literature was performed on studies investigating complement activation in PBC, PSC and AIH. Since data on AIH were lacking immunohistochemical staining for IgG, C1q, C3d, C4d and C5b9 was performed on liver tissue of nine AIH patients, two healthy controls and one positive control (acute liver failure caused by paracetamol intoxication).

RESULTS

Immunohistochemical analysis in AIH revealed increased production of C3 and C4 by hepatocytes. Despite a strong staining for IgG in the immune infiltrate in AIH, C3d, C4d and C5b9 deposition was only present in one AIH patient and the deposition was restricted to the interface between portal tracts and liver parenchyma. No deposition was found in all other AIH patients or healthy controls. Literature review showed raised plasma C3 and C4 levels in AIH, PBC and PSC patients compared to healthy controls. For PBC and PSC no complement depositions at the bile ducts were reported.

CONCLUSION AND DISCUSSION

Although complement is involved in various autoimmune diseases, the role of complement in autoimmune liver disease seems limited. Therefore it is unlikely that complement inhibition will become a novel treatment option for these diseases.

Successful Treatment of a Korean Infant with Giant Cell Hepatitis with Autoimmune Hemolytic Anemia Using Rituximab

Giant cell hepatitis with autoimmune hemolytic anemia (AHA) is a rare disease of infancy characterized by the presence of both Coombs-positive hemolytic anemia and progressive liver disease with giant cell transformation of hepatocytes. Here, we report a case involving a seven-month-old male infant who presented with AHA followed by cholestatic hepatitis. The clinical features included jaundice, pallor, and red urine. Physical examination showed generalized icterus and splenomegaly. The laboratory findings suggested warm-type AHA with cholestatic hepatitis. Liver biopsy revealed giant cell transformation of hepatocytes and moderate lobular inflammation. The patient was successfully treated with four doses of rituximab. Early relapse of hemolytic anemia and hepatitis was observed, which prompted the use of an additional salvage dose of rituximab. He is currently in clinical remission.

B-cell depletion induces prolonged remission in patients with giant cell hepatitis and autoimmune hemolytic anemia

BACKGROUND

Giant cell hepatitis with autoimmune hemolytic anemia (GCH-AHA) is a rare and severe immune-mediated disorder. Despite aggressive immunosuppressive treatments, the mortality is high. Prednisone has been effectively employed to achieve remission, but with a risk of relapse, if discontinued, and with severe side effects. A possible causative role of humoral immune response has paved the way to anti CD-20 monoclonal antibody (rituximab; RTX). Nevertheless, data about timing of remission and long-term side effects are sparse.

METHODS AND MATHERIALS

We have retrospectively evaluated 3 refractory GCH-AHA patients in whom a prolonged remission has been achieved with RTX. In all patients, response to first and second line therapy was incomplete or transitory and severe steroid side effects occurred.

RESULTS

A stable and sustained remission was achieved after multiple doses of RTX allowing withdrawing all the other treatments. No life-threatening infections have been recorded, however two patients developed persistent, paucisymptomatic hypogammaglobulinaemia. The only patient who did not develop hypogammaglobulinemia received IgG replacement during RTX.

CONCLUSION

RTX induced complete and long-lasting remission allowing discontinuing all the other immunosuppressive drugs. A persistent, paucisymptomatic hypogammaglobulinaemia has been the unique side effect. Although further studies need to replicate our data, RTX can be considered as an effective and safe therapy for sustained remission in patients with severe refractory GCH-AHA.

Relevance of C5b9 immunostaining in the diagnosis of neonatal hemochromatosis

BACKGROUND

Neonatal hemochromatosis caused by a gestational alloimmune mechanism or gestational alloimmune liver disease (GALD) is a rare perinatal disorder characterized by intra- and extrahepatic iron overload. It is believed to result from complement-mediated liver injury, in which the classical complement pathway is activated by maternal antibody/fetal antigen complexes, leading to hepatocyte lysis by the membrane attack complex C5b9. According to some authors, C5b9 expression in more than 75% of liver parenchyma is specific for GALD.

METHODS

We conducted a retrospective multicentric immunohistochemical study with anti-C5b9 in GALD cases (n = 25) and non-GALD cases with iron overload (n = 36) and without iron overload (n = 18).

RESULTS

C5b9 was expressed in 100% of GALD cases but involved more than 75% of the liver parenchyma in only 26% of the cases. C5b9 was detected in 26.75% of the non-GALD cases with more than 75% of positive parenchyma in maternal erythrocytic alloimmunization, herpes and enterovirus hepatitis, bile acid synthetic defect, DGUOK mutation, Gaucher disease, cystic fibrosis, and giant-cell hepatitis with autoimmune hemolytic anemia.

CONCLUSION

Diagnosis and therapeutic management of GALD cannot only be based on C5b9 expression in liver samples as it is not specific of this disease.

Giant cell hepatitis with autoimmune hemolytic anemia in a Korean infant

Giant cell hepatitis (GCH) with autoimmune hemolytic anemia (AHA) is a very rare disease characterized by early onset and severe clinical manifestations, including immune hemolytic anemia and hepatitis with cholestasis. The prognosis is poor despite aggressive immunosuppressive therapy. We report here the first case of GCH with AHA in East Asia. A 2-month-old boy was admitted with jaundice. Blood test indicated abnormal liver function and low hemoglobin. Direct Coombs test and several autoantibodies associated with liver disease were positive, and liver biopsy was consistent with GCH. He was treated with prednisolone and ursodeoxycholic acid, and at the time of writing was in clinical and biochemical remission after prednisolone was stopped.

Efficacy of intravenous immunoglobulin therapy in giant cell hepatitis with autoimmune hemolytic anemia: A multicenter study

BACKGROUND AND OBJECTIVE

Giant cell hepatitis with autoimmune hemolytic anemia (GCH-AHA) is a rare disease of infancy, of possible autoimmune mechanism with poor prognosis due to its scarce response to immunosuppressive drugs. The aim of this retrospective multicenter study was to evaluate the efficacy and safety of intravenous immunoglobulin (IVIg) treatment in inducing and maintaining remission of the liver disease, in patients with GCH-AHA.

METHODS

Seven children with GCH-AHA, four newly diagnosed, and three in relapse, being treated with different therapies, received one to three IVIg infusions (0.5 to 2g/kg) in association with other immunosuppressive drugs. Subsequently five of them received monthly sequential IVIg infusions (mean 13.4, range 7-24).

RESULTS

IVIg infusions as first-line therapy associated with prednisone and other immunosuppressive drugs significantly (P=0.04) reduced the aminotransferase activity in all patients and normalized prothrombin activity in the only patient with severe liver dysfunction. Sequential monthly IVIg infusions determined a steroid-sparing effect and allowed a complete or partial remission in all patients, although with temporary efficacy, since relapse of the hemolytic anemia and/or of liver disease occurred in all patients. IVIg infusions were associated with mild side effects in two patients.

CONCLUSIONS

IVIg infusion can be safely and effectively administered in patients with severe GCH-AHA at diagnosis, or in case of relapse, in association with other immunosuppressive drugs. Repeated IVIg infusions may help maintain remission, however, due to their temporary efficacy, they should not be routinely employed.

Anti-CD20 treatment of giant cell hepatitis with autoimmune hemolytic anemia

Giant cell hepatitis with autoimmune hemolytic anemia (GCH-AHA) is a rare autoimmune disease of infancy characterized by severe liver disease associated with Coombs-positive hemolytic anemia. We recently showed that GCH-AHA is probably caused by a humoral immune mechanism. Such data support the use of rituximab, an anti-CD-20 monoclonal antibody specifically targeting B lymphocytes, as a treatment for GCH-AHA. We describe here the detailed clinical evolution of 4 children with GCH-AHA who showed a complete response to rituximab. All patients shared a severe course of the disease with poor control on standard and aggressive immunosuppression. Rituximab was well tolerated, and no side effects or infections were registered. Several doses were needed to induce remission, and 5 to 11 additional maintenance injections were necessary in the 2 more severe cases. Weaning from corticosteroids was achieved in all subjects. A steroid-sparing effect was noted in the 3 children who started rituximab early in the course of the disease. Overall, we show here that there is a strong rationale for treating GCH-AHA with rituximab. Early treatment could reduce the use of corticosteroids. Nevertheless, short-term steroids should be initially associated with rituximab to account for autoantibodies' half-life. Repeated injections are needed to treat and prevent relapses, but the best frequency and duration of treatment remain to be defined.

Juvenile autoimmune hepatitis: Spectrum of the disease

Juvenile autoimmune hepatitis (JAIH) is a progressive inflammatory liver disease, affecting mainly young girls, from infancy to late adolescence, characterized by active liver damage, as shown by high serum activity of aminotransferases, by elevated immunoglobulin G levels, high titers of serum non organ-specific and organ-specific autoantibodies, and by interface hepatitis on liver biopsy. It is a multifactorial disease of unknown etiology in which environmental factors act as a trigger in genetically predisposed individuals. Two types of JAIH are identified according to the autoantibody panel detected at diagnosis: AIH-1, characterized by the presence of anti-smooth muscle antibody and/or antinuclear antibody and AIH-2, by anti-liver-kidney microsomal antibody type 1 and/or by the presence of anti-liver cytosol type 1 antibody. Epidemiological distribution, genetic markers, clinical presentation and pattern of serum cytokines differentiate the two types of AIH suggesting possible pathogenetic mechanisms. The most effective therapy for AIH is pharmacological suppression of the immune response. Treatment should be started as soon as the diagnosis is made to avoid severe liver damage and progression of fibrosis. The aim of this review is to outline the most significant and peculiar features of JAIH, based largely on our own personal database and on a review of current literature.