Immune-mediated hepatitis-associated aplastic anemia caused by the emergence of a mutant hepatitis B virus undetectable by standard assays

Diagnostic Approach and Pathophysiological Mechanisms of Anemia in Chronic Liver Disease—An Overview

Hematological abnormalities are frequently linked to chronic liver disease of any etiology. About 75% of patients with advanced chronic liver disease experience anemia. The causes of anemia are complex and multifactorial, particularly in cirrhotic patients. Acute and long-term blood loss from the upper gastrointestinal tract, malnutrition, an enlarged spleen brought on by portal hypertension, hemolysis, and coagulation issues are the main causes of anemia. Alcohol, a common cause of chronic liver disease, determines anemia through direct toxicity on the bone marrow, with the suppression of hematopoiesis, through vitamin B6, B12, and folate deficiency due to low intake and malabsorption. In patients with chronic hepatitis C virus infection, antiviral drugs such as pegylated interferon and ribavirin can also cause significant anemia. The use of interferon has been linked to bone marrow toxicity, and hemolytic anemia brought on by ribavirin is a well-known dose-dependent side effect. Within six months of the infection with hepatitis B, hepatitis C, and Epstein–Barr viruses, aplastic anemia associated with hepatitis is seen. This anemia is characterized by pancytopenia brought on by hypocellular bone marrow. Esophageal varices, portal hypertensive gastropathy, and gastric antral vascular ectasia can all cause acute and chronic blood loss. These conditions can progress to iron deficiency anemia, microcytic anemia, and hypochromic anemia. Another common hematologic abnormality in liver cirrhosis is macrocytosis, with multifactorial causes. Vitamin B12 and folate deficiency are frequent in liver cirrhosis, especially of alcoholic etiology, due to increased intestinal permeability, dysbiosis, and malnutrition. Many chronic liver diseases, like viral and autoimmune hepatitis, have a chronic inflammatory substrate. Proinflammatory cytokines, including tumor necrosis factor and interleukin 1, 6, and 10, are the main factors that diminish iron availability in progenitor erythrocytes and subsequent erythropoiesis, leading to the development of chronic inflammatory, normochromic, normocytic anemia.

Patient Blood Management in Liver Transplant—A Concise Review

Transfusion of blood products in orthotopic liver transplantation (OLT) significantly increases post-transplant morbidity and mortality and is associated with reduced graft survival. Based on these results, an active effort to prevent and minimize blood transfusion is required. Patient blood management is a revolutionary approach defined as a patient-centered, systematic, evidence-based approach to improve patient outcomes by managing and preserving a patient’s own blood while promoting patient safety and empowerment. This approach is based on three pillars of treatment: (1) detecting and correcting anemia and thrombocytopenia, (2) minimizing iatrogenic blood loss, detecting, and correcting coagulopathy, and (3) harnessing and increasing anemia tolerance. This review emphasizes the importance of the three-pillar nine-field matrix of patient blood management to improve patient outcomes in liver transplant recipients.

Herpes Simplex Virus-Associated Aplastic Anemia

Aplastic anemia is an uncommon condition defined by peripheral pancytopenia in the context of hypocellular bone marrow. In the majority of cases, it is idiopathic in origin. However, exposure to certain drugs and toxins, autoimmune processes, and viral infections have been linked to this entity. This is the case of a 56-year-old female with an acute presentation of fever, odynophagia, and dysphagia. Physical examination revealed multiple hemorrhagic ulcers affecting her oropharyngeal mucosa with regions of necrosis. Mucosal biopsy was compatible with the presence of local necrosis and keratinization. Hematological analysis showed severe peripheral pancytopenia, and the bone marrow biopsy revealed a hypocellular marrow, findings consistent with aplastic anemia. An ample PCR viral panel revealed the presence of herpes simplex virus type 1 (HSV-1). The patient was placed on systemic antiviral therapy, followed by a rapid improvement of the mucositis as well as the peripheral and central pancytopenia. Our case indicated the possible association of HSV-1 infection and the development of aplastic anemia, an important and not yet recognized association considering the rapid improvement of the clinical picture once the underlying etiology was addressed.

Changes in bone marrow and peripheral blood lymphocyte subset findings with onset of hepatitis-associated aplastic anemia

RATIONALE

Hepatitis-associated aplastic anemia (HAAA) is a rare illness that results in bone marrow failure following hepatitis development. The etiological agent remains unknown in most HAAA cases. However, clinical features of the disease and immunotherapy response indicate that immune-mediated factors play a central role in the pathogenesis of HAAA. Activation of cytotoxic T cells and increase in CD8 cells could exert cytotoxic effects on the myelopoietic cells in the bone marrow.

PATIENT CONCERNS

A 15-month-old boy was brought to our hospital with complaints of generalized petechiae and purpura observed a week prior to hospitalization. His liver was palpated 3 cm below the costal margin, platelet count was 0 × 104/μL, and alanine aminotransferase level was 1346 IU/L. A blood test indicated cytomegalovirus infection, and 3 bone marrow examinations revealed progressive HAAA. As the disease progressed to the 3rd, 6th, and 9th week after onset, CD4+ T cells were markedly decreased, CD8+ T cells were markedly increased, and the CD4/CD8 ratio was significantly decreased. The number of B cells and natural killer cells decreased with time, eventually reaching 0.0%.

DIAGNOSIS

HAAA.

INTERVENTIONS

Rabbit antithymocyte globulin and eltrombopag olamine (a thrombopoietin receptor agonist) were administered.

OUTCOMES

The patient's platelet count returned to normal, and bone marrow transplantation was avoided. The peripheral blood lymphocytes (PBLs) improved as the patient's general condition recovered.

LESSONS

This case demonstrates that HAAA induced by cytomegalovirus infection features decreasing CD4+ and increasing CD8+ PBLs as the bone marrow hypoplasia progresses. The PBLs return to their normal levels with the recovery from the disease. Our case findings thus support the involvement of immunological abnormality in HAAA.

Outcome of anti-thymocyte immunoglobulin plus cyclosporine A for severe aplastic anaemia with chronic hepatitis B virus infection

The influence of chronic hepatitis B virus (HBV) infection on the efficacy of intensive immunosuppressive treatment (IST) of severe aplastic anaemia (SAA) patients remains unclear. Previous reports on this topic have been mostly case reports or have had a relatively short follow-up. Eight SAA patients carrying chronic HBV infection and 24 matched patients without HBV at a ratio of 1:3 were included in this retrospective analysis. The patients were treated with anti-thymocyte globulin (ATG) and cyclosporine A. Entecavir was or was not administered throughout the IST course to patients with positive or negative HBV-DNA results, respectively. No evident HBV reactivation developed. The overall response was 87.5% by 12 months, and the recurrence rate was 12.5%. There were no significant differences in overall response, overall survival and event-free survival between groups. Entecavir can effectively prevent reactivation of HBV in SAA patients with positive HBV-DNA who received intensive IST. Regular surveillance may be sufficient for HBV-DNA negative patients who should receive antiviral drugs immediately when their HBV-DNA status changes from negative to positive. The prognosis of SAA patients with chronic HBV infection after intensive IST treatment is not worse than those without HBV infection.

Glycated Hemoglobin Levels in Patients with Decompensated Cirrhosis

Introduction. Aim of this study is to determine if HbA1c levels are a reliable predictor of glycemic control in patients with decompensated cirrhosis. Methods. 200 unique patients referred for liver transplantation at University of Tennessee/Methodist University Transplant Institute with a HbA1c result were included. Three glucose levels prior to the "measured" A1c (MA1c) were input into an HbA1c calculator from the American Diabetes Association website to determine the "calculated" A1c (CA1c). The differences between MA1c and CA1c levels were computed. Patients were divided into three groups: group A, difference of <0.5; group B, 0.51-1.5; and group C, >1.5. Results. 97 (49%) patients had hemoglobin A1c of less than 5%. Discordance between calculated and measured HbA1c of >0.5% was seen in 47% (n = 94). Higher level of discordance of greater than >1.5 was in 12% of patients (n = 24). Hemoglobin was an independent predictor for higher discordance (odds ratio 0.77 95%, CI 0.60-0.99, and p value 0.04). HbA1c was an independent predictor of occurrence of HCC (OR 2.69 955, CI 1.38-5.43, and p value 0.008). Conclusion. HbA1c is not a reliable predictor of glycemic control in patients with decompensated cirrhosis, especially in those with severe anemia.

Concise review: Anemia caused by viruses

Most of the viruses known to be associated with anemia in human tend to persistently infect their host and are noncytopathic or poorly cytopathic for blood cell progenitors. Infections with Epstein-Barr virus, cytomegalovirus, varicella-zoster virus, human herpes virus 6 (HHV-6), B19 parvovirus, human immunodeficiency virus, hepatitis A and C viruses and the putative viral agent associated with non-A-G post-hepatitis aplastic anemia have been reported in association with anemia. Nevertheless, a direct cytotoxic effect on erythroid progenitors has been clearly demonstrated only for human parvovirus B19 and evocated for HHV-6. A major role for destructive immunity is strongly suspected in the pathogenesis of anemia associated with the other viral infections. Host genes play a role in the occurrence of virus-induced anemia in animal models, and there are some evidences that genetic background could also influence the occurrence of virus-associated anemia in human.

Spectrum of anemia associated with chronic liver disease

Anemia of diverse etiology is a common complication of chronic liver diseases. The causes of anemia include acute or chronic gastrointestinal hemorrhage, and hypersplenism secondary to portal hypertension. Severe hepatocellular disease predisposes to hemorrhage because of impaired blood coagulation caused by deficiency of blood coagulation factors synthesized by hepatocytes, and/or thrombocytopenia. Aplastic anemia, which is characterized by pancytopenia and hypocellular bone marrow, may follow the development of hepatitis. Its presentation includes progressive anemia and hemorrhagic manifestations. Hematological complications of combination therapy for chronic viral hepatitis include clinically significant anemia, secondary to treatment with ribavirin and/or interferon. Ribavirin-induced hemolysis can be reversed by reducing the dose of the drug or discontinuing it altogether. Interferons may contribute to anemia by inducing bone marrow suppression. Alcohol ingestion is implicated in the pathogenesis of chronic liver disease and may contribute to associated anemia. In patients with chronic liver disease, anemia may be exacerbated by deficiency of folic acid and/or vitamin B12 that can occur secondary to inadequate dietary intake or malabsorption.

Systematic review: hepatitis-associated aplastic anaemia--a syndrome associated with abnormal immunological function

BACKGROUND

Hepatitis-associated aplastic anaemia is a syndrome in which marrow failure follows the development of hepatitis.

AIM

To review systematically the aetiology, immunopathogenesis, clinical presentation, diagnosis and treatment of hepatitis-associated aplastic anaemia.

METHODS

Literature searches were undertaken on the MEDLINE electronic database up to December 2008. Twenty-four relevant studies were identified. The clinical and laboratory characteristics of the patients were analysed and reviewed.

RESULTS

Hepatitis-associated aplastic anemia is a variant of acquired aplastic anemia in which an episode of hepatitis precedes the onset of aplastic anemia. The hepatitis may be acute and severe, even fulminant; it may be self-limiting or chronic. The pathology is often not attributable to a recognized cause of viral hepatitis. The syndrome occurs in 28 percent of young adults after liver transplantation for non-A, non-B, non-C hepatitis. Several features of the syndrome suggest that the marrow aplasia is mediated by immunological mechanisms, possibly mediated by gamma interferon or the cytokine cascade. Survival of patients treated with hematopoietic cell transplantation has been 82%, and the response rate to immunosuppressive therapy 70%.

CONCLUSIONS

Hepatitis-associated bone marrow aplasia is mediated by immunological mechanisms. Treatment options include hematopoietic cell transplantation and immunosuppressive therapy.

Molecular characterization of a variant virus that caused de novo hepatitis B without elevation of hepatitis B surface antigen after chemotherapy with rituximab

Hepatitis B virus (HBV) reactivation in hepatitis B surface antigen (HBsAg)-negative patients following treatment with rituximab has been reported increasingly. The aim of this study was to investigate the molecular mechanisms underlying HBV reactivation in an HBsAg-negative patient. HBV was reactivated in a 75-year-old man following chemotherapy with rituximab, without elevation of HBsAg. The patient's full-length HBV genome was cloned and the entire sequence was determined. Transfection studies were performed in vitro using recombinant wild-type HBV (wild-type), the patient's HBV (patient), and two chimeric HBV constructs, in which the preS/S region of the patient and wild-type virus had been exchanged with one another. Secreted HBsAg and intra- and extra-cellular HBV DNA were measured. The number of amino acid substitutions in HBV from this patient was much higher than in previous reports of HBV mutants, such as occult HBV and vaccine escape HBV mutants. Levels of HBsAg and HBV DNA production in vitro were significantly lower in the patient compared to wild-type transfections. From analyses of the chimeric constructs, the altered preS/S region was responsible mainly for this impairment. These results show that highly mutated HBV can reactivate after chemotherapy with rituximab, despite an unusually large number of mutations, resulting in impaired viral replication in vitro. Severe immune suppression, probably caused by rituximab, may permit reactivation of highly mutated HBV. These findings have important clinical implications for the prevention and management of HBV reactivation and may explain partially the mechanism of recent, unusual cases of HBV reactivation.

Biological and clinical implications of HBV infection in peripheral blood mononuclear cells

The liver is the main site of HBV replication, however extrahepatic organs, such as the lymphoid system, are an important reservoir of the virus. Viral DNA into different mononuclear cell subsets has been mainly detected in monocytes and B lymphocytes. The attachment site of the virus has been identified in the preS1 encoded protein of the virus envelope, the same involved in hepatocyte infection. The risk of HBV transmission by infected lymphocytes has been clearly documented in the setting of liver transplantation where de novo HBV infection has been found in up to about 80% of liver grafts from HBsAg negative but anti-HBc positive donors. In the hemodialysis setting the percentage of HBV DNA detection in mononuclear cells of HBsAg negative patients has been described in up to 54% of the cases. Vertical transmission studies indicate that HBV-infected mononuclear cells of the mother may result in viral infection of mononuclear cells of the newborns and possible HBV vaccine response failure. HBV can also infect bone marrow cells and in vitro studies demonstrate a block of hematopoiesis by HBV, supporting clinical observations of isolate cases of aplastic anemia associated to the infection.