Centrilobular zonal necrosis is a unique subtype of autoimmune hepatitis: A cohort study

BACKGROUNDS

Centrilobular zonal necrosis (CZN) is described as a histological feature present in a small number of autoimmune hepatitis (CZN-AIH) patients. CZN may be detected in the absence of significant interface hepatitis, which is the most important histological finding of AIH. The clinical and histopathological spectra of CZN-AIH were not homogeneous, and the concept of CZN-AIH as a distinctive subtype of AIH remains controversial, due to the rarity of CZN-AIH and the ambiguous definition of CZN.

METHODS

To elucidate the clinical and immunogenetic features of CZN-AIH, a total of 102 biopsy samples of AIH, obtained at The Jikei University Katsushika Medical Center and Jikei University Hospital from 2000 to 2018, were reviewed. The 32 patients whose biopsies showed CZN were selected as the CZN-AIH group, and the remaining 70 were grouped as the non-CZN-AIH controls (control AIH). Data on clinical, histopathologic, and immunogenetic features were statistically compared between the CZN-AIH and the control AIH group. Additionally, the impact of the onset pattern (acute or chronic) and coexistent significant interface hepatitis in CZN-AIH was determined.

RESULTS

In CZN-AIH, the frequency of acute-onset cases was significantly higher than that in control AIH (56.2% vs 32.9%; P < .05), and the number of cases with moderate-to-severe interface hepatitis in liver histology was significantly lower (37.5% vs 87.1%; P < .001). Compared to the control AIH, cases of CZN-AIH had lower immunoglobulin G level (P < .001), lower antinuclear antibodies titer (P < .001), and lower AIH score (P < .001). The immunogenetic disproportionate distribution of HLA-DR phenotypes in control AIH (increased HLA-DR4 and decreased HLA-DR9) was not found in CZN-AIH. Moreover, CZN-AIH was less frequently relapsed (P < .05). For the acute-onset CZN-AIH cases, the clinical features were hardly indistinguishable from the chronic CZN-AIH cases. Similarly, the existence of interface hepatitis did not influence on the pathophysiology of CZN-AIH. Moreover, the acute-onset CZN-AIH cases is clinically distinguishable from acute-onset control AIH.

CONCLUSION

CZN can characterize as a distinct AIH subtype, regardless of onset-pattern or coexistence of significant interface hepatitis. To further strengthen this hypothesis, collection of more CZN-AIH cases is needed.

Impact of interferon-free antivirus therapy on lipid profiles in patients with chronic hepatitis C genotype 1b

AIM

To investigate the influence of interferon-free antivirus therapy on lipid profiles in chronic hepatitis C virus genotype 1b (HCV1b) infection.

METHODS

Interferon-free antiviral agents were used to treat 276 patients with chronic HCV1b infection, and changes in serum lipids of those who achieved sustained virologic response (SVR) were examined. The treatment regimen included 24 wk of daclatasvir plus asunaprevir (DCV + ASV) or 12 wk of sofosbuvir plus ledipasvir (SOF + LDV). SVR was achieved in 121 (85.8%) of 141 patients treated with DCV + ASV and 132 (97.8%) of 135 patients treated with SOF + LDV. In the two patient groups (DCV + ASV-SVR and SOF + LDV-SVR), serum total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), and triglycerides were measured at baseline during treatment and at 4 and 12 wk after treatment. Then, longitudinal changes in lipid profiles were analyzed.

RESULTS

Serum levels of TC, LDL-C, and HDL-C were significantly increased throughout the observation period in both the DCV + ASV-SVR and SOF + LDV-SVR groups. During antivirus treatment, the increases in TC and LDL-C were significantly greater in the SOF + LDV-SVR group than in the DCV + ASV-SVR group (P < 0.001). At 4 and 12 wk after the therapy, serum levels of TC and LDL-C were similar between the two groups and were significantly greater than those at baseline. Approximately 75%-80% of the increase in TC was derived from an increased LDL-C. In multiple regression analysis, the difference in therapy protocol (DCA + ASV or SOF + LDV) was an independent predictor that was significantly associated with the increase in TC and LDL-C at 4 wk of therapy.

CONCLUSION

Serum cholesterol significantly increased during SOF + LDV treatment. After treatment, HCV elimination was associated with a similar increase in cholesterol regardless of the therapy protocol.

Autoimmune hepatitis: current challenges and future prospects

Autoimmune hepatitis (AIH) is a chronic progressive liver disease characterized by high levels of aminotransferases and autoantibodies, hypergammaglobulinemia, and interface hepatitis. AIH affects all races and all ages worldwide, regardless of sex, although a preponderance of females is a constant finding. The etiology of AIH has not been completely elucidated, but immunogenetic background and environmental parameters may contribute to its development. The most important genetic factor is human leukocyte antigens (HLAs), especially HLA-DR, whereas the role of environmental factors is not completely understood. Immunologically, disruption of the immune tolerance to autologous liver antigens may be a trigger of AIH. The diagnosis of classical AIH is fairly easy, though not without pitfalls. In contrast, the diagnosis of atypical AIH poses great challenges. There is confusion as to the definition of the disease entity and its boundaries in the diagnosis of overlap syndrome, drug-induced autoimmune hepatitis, and AIH with concomitant nonalcoholic fatty liver disease (NAFLD) or chronic hepatitis C. Centrilobular zonal necrosis is now included in the histological spectrum of AIH. However, the definition and the significance of AIH presenting with centrilobular zonal necrosis have not been examined extensively. In ~20% of AIH patients who are treated for the first time with standard therapy, remission is not achieved. The development of more effective and better tolerated novel therapies is an urgent need. In this review, we discuss the current challenges and the future prospects in relation to the diagnosis and treatment of AIH, which have been attracting considerable recent attention.

Hepatitis C virus G1b infection decreases the number of small low-density lipoprotein particles

AIM: To investigate how hepatitis C virus (HCV) G1b infection influences the particle number of lipoproteins.

METHODS: The numbers of lipoprotein particles in fasting sera from 173 Japanese subjects, 82 with active HCV G1b infection (active HCV group) and 91 with cleared HCV infection (SVR group), were examined. Serum lipoprotein was fractionated by high-performance liquid chromatography into twenty fractions. The cholesterol and triglyceride concentrations in each fraction were measured using LipoSEARCH. The number of lipoprotein particles in each fraction was calculated using a newly developed algorithm, and the relationship between chronic HCV G1b infection and the lipoprotein particle number was determined by multiple linear regression analysis.

RESULTS: The median number of low-density lipoprotein (LDL) particles was significantly lower in the active HCV group [1182 nmol/L, interquartile range (IQR): 444 nmol/L] than in the SVR group (1363 nmol/L, IQR: 472 nmol/L, P < 0.001), as was that of high-density lipoprotein (HDL) particles (14168 nmol/L vs 15054 nmol/L, IQR: 4114 nmol/L vs 3385 nmol/L, P = 0.042). The number of very low-density lipoprotein (VLDL) particles was similar between the two groups. Among the four LDL sub-fractions, the number of large LDL particles was similar between the two groups. However, the numbers of medium (median: 533.0 nmol/L, IQR: 214.7 nmol/L vs median: 633.5 nmol/L, IQR: 229.6 nmol/L, P < 0.001), small (median: 190.9 nmol/L, IQR: 152.4 nmol/L vs median: 263.2 nmol/L, IQR: 159.9 nmol/L; P < 0.001), and very small LDL particles (median: 103.5 nmol/L, IQR: 66.8 nmol/L vs median: 139.3 nmol/L, IQR: 67.3 nmol/L, P < 0.001) were significantly lower in the active HCV group than in the SVR group, respectively. Multiple linear regression analysis indicated an association between HCV G1b infection and the decreased numbers of medium, small, and very small LDL particles. However, active HCV infection did not affect the number of large LDL particles or any sub-fractions of VLDL and HDL particles.

CONCLUSION: HCV G1b infection decreases the numbers of medium, small, and very small LDL particles.

Centrilobular zonal necrosis as a hallmark of a distinctive subtype of autoimmune hepatitis

BACKGROUND AND AIM

Centrilobular zonal necrosis (CZN) is a known histological variant of autoimmune hepatitis (AIH). However, the significance of CZN is yet to be fully elucidated. This study aimed to determine whether CZN is a hallmark of a distinctive subtype of AIH.

METHODS

Histological changes in the centrilobular zones of liver biopsies from 113 AIH patients were assessed by a single pathologist and classified into three categories: typical zonal necrosis defined as CZN (15 patients); other necroinflammatory change (NIC; 24 patients); and absence of necrosis (non-NIC; 74 patients). The clinicopathological features and immunogenetic background of CZN patients were then assessed.

RESULTS

The clinicopathological features of AIH with CZN were distinct from other types of AIH, including a higher frequency of acute onset, lower frequency of antinuclear antibodies, lower antinuclear antibody titers, lower serum immunoglobulin G levels, lower grade interface hepatitis, less prominent lymphoplasmacytic infiltration, and lower AIH score. Increased and decreased frequencies of HLA-DR9 and HLA-DR4, respectively, were identified as immunogenetic features of AIH with CZN. Conversely, the clinicopathological characteristics of AIH with NIC were similar to those of non-NIC AIH, including the majority of the AIH patients. The therapeutic outcomes of AIH with CZN were excellent when precise diagnoses were made without delay.

CONCLUSION

The clinicopathological features and immunogenetic background of AIH with CZN differed from AIH without CZN. CZN may be a hallmark of a distinct subtype of AIH.

High level of serum cholesteryl ester transfer protein in active hepatitis C virus infection

AIM: To determine the significance of cholesteryl ester transfer protein (CETP) in lipoprotein abnormalities in chronic hepatitis C virus (HCV) infection.

METHODS: We evaluated the significance of the serum concentration of CETP in 110 Japanese patients with chronic HCV infection. Fifty-five patients had active HCV infection, and HCV eradication had been achieved in 55. The role of CETP in serum lipoprotein abnormalities, specifically, in triglyceride (TG) concentrations in the four major classes of lipoproteins, was investigated using Pearson correlations in conjunction with multiple regression analysis and compared them between those with active HCV infection and those in whom eradication had been achieved.

RESULTS: The serum CETP levels of patients with active HCV infection were significantly higher than those of patients in whom HCV eradication was achieved (mean ± SD, 2.84 ± 0.69 μg/mL vs 2.40 ± 1.00 μg/mL, P = 0.008). In multiple regression analysis, HCV infection status (active or eradicated) was an independent factor significantly associated with the serum CETP level. TG concentrations in low-density lipoprotein (mean ± SD, 36.25 ± 15.28 μg/mL vs 28.14 ± 9.94 μg/mL, P = 0.001) and high-density lipoprotein (HDL) (mean ± SD, 25.9 ± 7.34 μg/mL vs 17.17 ± 4.82 μg/mL, P < 0.001) were significantly higher in patients with active HCV infection than in those in whom HCV eradication was achieved. The CETP level was strongly correlated with HDL-TG in patients with active HCV infection (R = 0.557, P < 0.001), whereas CETP was not correlated with HDL-TG in patients in whom HCV eradication was achieved (R = -0.079, P = 0.56).

CONCLUSION: Our results indicate that CETP plays a role in abnormalities of lipoprotein metabolism in patients with chronic HCV infection.

Evaluation of the role of HLA-DR antigens in Japanese type 1 autoimmune hepatitis

Background

The role of HLA-DR antigens in the clinicopathological features of autoimmune hepatitis (AIH) is not clearly understood. We examined the implications of HLA-DR antigens in Japanese AIH, including the effect of HLA-DR4 on the age and pattern of AIH onset, clinicopathological features, and treatment efficacy.

Methods

A total of 132 AIH patients consecutively diagnosed and treated in 2000–2014 at 2 major hepatology centers of eastern Tokyo district were the subjects of this study. The frequency of HLA-DR phenotypes was compared with that in the healthy Japanese population. AIH patients were divided into HLA-DR4–positive or HLA-DR4–negative groups and further sub-classified into elderly and young-to-middle-aged groups, and differences in clinical and histological features were examined. Clinical features associated with the response to immunosuppressive therapy were also determined.

Results

The frequency of the HLA-DR4 phenotype was significantly higher in AIH than in control subjects (59.7 % vs. 41.8 %, P < 0.001), and the relative risk was 2.14 (95 % CI; 1.51–3.04). HLA-DR4–positive AIH patients were younger than HLA-DR4–negative patients (P = 0.034). Serum IgG and IgM levels were higher (P < 0.001 and P = 0.007, respectively) in HLA-DR4–positive patients. These differences were more prominent in elderly AIH patients. However, there was no difference in IgG and IgM levels between HLA-DR4–positive and HLA-DR4–negative patients of the young-to-middle-aged group. There were no differences in the histological features. In patients with refractory to immunosuppressive therapy, higher total bilirubin, longer prothrombin time, lower serum albumin, and lower platelet count were found. Imaging revealed splenomegaly to be more frequent in refractory patients than in non-refractory patients (60.0 % vs. 30.8 %, P = 0.038). HLA-DR phenotype distribution was similar regardless of response to immunosuppressive therapy.

Conclusions

HLA-DR4 was the only DR antigen significantly associated with Japanese AIH. The clinical features of HLA-DR4–positive AIH differed between elderly patients and young-to-middle-aged patients. Treatment response depended on the severity of liver dysfunction but not on HLA-DR antigens.

Chronic hepatitis C virus infection and lipoprotein metabolism

Hepatitis C virus (HCV) is a hepatotrophic virus and a major cause of chronic liver disease, including hepatocellular carcinoma, worldwide. The life cycle of HCV is closely associated with the metabolism of lipids and lipoproteins. The main function of lipoproteins is transporting lipids throughout the body. Triglycerides, free cholesterol, cholesteryl esters, and phospholipids are the major components of the transported lipids. The pathway of HCV assembly and secretion is closely linked to lipoprotein production and secretion, and the infectivity of HCV particles largely depends on the interaction of lipoproteins. Moreover, HCV entry into hepatocytes is strongly influenced by lipoproteins. The key lipoprotein molecules mediating these interactions are apolipoproteins. Apolipoproteins are amphipathic proteins on the surface of a lipoprotein particle, which help stabilize lipoprotein structure. They perform a key role in lipoprotein metabolism by serving as receptor ligands, enzyme co-factors, and lipid transport carriers. Understanding the association between the life cycle of HCV and lipoprotein metabolism is important because each step of the life cycle of HCV that is associated with lipoprotein metabolism is a potential target for anti-HCV therapy. In this article, we first concisely review the nature of lipoprotein and its metabolism to better understand the complicated interaction of HCV with lipoprotein. Then, we review the outline of the processes of HCV assembly, secretion, and entry into hepatocytes, focusing on the association with lipoproteins. Finally, we discuss the clinical aspects of disturbed lipid/lipoprotein metabolism and the significance of dyslipoproteinemia in chronic HCV infection with regard to abnormal apolipoproteins.

Influencing factors on serum 25-hydroxyvitamin D3 levels in Japanese chronic hepatitis C patients

Background

Serum 25-hydroxyvitamin D₃ levels are generally lower in chronic hepatitis C patients than in healthy individuals. The purpose of this study is to clarify the factors which affect serum 25-hydroxyvitamin D₃ levels using data obtained from Japanese chronic hepatitis C patients.

Methods

The subjects were 619 chronic hepatitis C patients. Serum 25-hydroxyvitamin D₃ levels were measured by using double-antibody radioimmunoassay between April 2009 and August 2014. Serum 25-hydroxyvitamin D₃ levels of 20 ng/mL or less were classified as vitamin D deficiency, and those with serum 25-hydroxyvitamin D₃ levels of 30 ng/mL or more as vitamin D sufficiency. The relationship between patient-related factors and serum 25-hydroxyvitamin D₃ levels was analyzed.

Results

The cohort consisted of 305 females and 314 males, aged between 18 and 89 years (median, 63 years). The median serum 25-hydroxyvitamin D₃ level was 21 ng/mL (range, 6–61 ng/mL). On the other hand, the median serum 25-hydroxyvitamin D₃ level in the healthy subjects was 25 ng/mL (range, 7–52), being significantly higher than that those in 80 chronic hepatitis C patients matched for age, gender, and season (p = 1.16 × 10⁻⁸). In multivariate analysis, independent contributors to serum 25-hydroxyvitamin D₃ deficiency were as follows: female gender (p = 2.03 × 10⁻⁴, odds ratio = 2.290, 95 % confidence interval = 1.479–3.545), older age (p = 4.30 × 10⁻⁴, odds ratio = 1.038, 95 % confidence interval = 1.017–1.060), cold season (p = 0.015, odds ratio = 1.586, 95 % confidence interval = 1.095–2.297), and low hemoglobin level (p = 0.037, odds ratio = 1.165, 95 % confidence interval = 1.009–1.345). By contrast, independent contributors to serum 25-hydroxyvitamin D₃ sufficiency were male gender (p = 0.001, odds ratio = 3.400, 95 % confidence interval = 1.635–7.069), warm season (p = 0.014, odds ratio = 1.765, 95 % confidence interval = 1.117–2.789) and serum albumin (p = 0.016, OR = 2.247, 95 % CI = 1.163–4.342).

Conclusions

Serum 25-hydroxyvitamin D₃ levels in chronic hepatitis C Japanese patients were influenced by gender, age, hemoglobin level, albumin and the season of measurement.

Serum lipoprotein profiles and response to pegylated interferon plus ribavirin combination therapy in patients with chronic HCV genotype 1b infection

BACKGROUND

Abnormal serum lipid profiles have been noted in patients with chronic hepatitis C virus (HCV) infection. Moreover, many reports suggest that serum lipoprotein profiles are more profoundly distorted in patients with HCV G1b infection who have an unfavorable response to pegylated interferon (peg-IFN) plus ribavirin (RBV) combination therapy. However, after the discovery of single nucleotide polymorphisms near the IL28B gene (rs8099917 and rs12979860) as potent predictive factors affecting the response to peg-IFN plus RBV, lipid factors are thought to be confounding factors.

OBJECTIVES

To re-examine the significance of lipoprotein profiles on virological response to peg-IFN plus RBV combination therapy in patients with chronic HCV G1b infection, we examined cholesterol and triglyceride concentrations in each lipoprotein fraction separated by high performance liquid chromatography.

PATIENTS AND METHODS

Lipoprotein profiles were examined using fasting sera from 108 patients infected with HCV G1b who had chronic hepatitis, as determined by liver biopsy. Results of lipoprotein profiles and clinical data, including IL28B genotype and amino acid substitution at aa70 of HCV G1b, were compared between patients with a sustained virological response (SVR) and non-SVR or a non-virological response (NVR) and virological responses other than NVR (non-NVR). In addition, significant predictive factors independently associated with virological response to peg-IFNα-2b plus RBV were determined by logistic regression analysis.

RESULTS

An increased ratio of cholesterol/triglyceride in very low-density lipoprotein (odds ratio (OR) 3.03; 95% confidence interval (CI) 1.01-9.44) along with a major genotype of rs8099917 (OR 9.09; 95% CI 2.94-33.33), were independent predictive factors for SVR. In contrast, lipid factors were not elucidated as independent predictive factors for NVR.

CONCLUSIONS

Examination of the fasting lipid profile has clinical importance in predicting the efficacy of peg-IFN-α-2b plus RBV combination therapy for patients with HCV G1b even after the discovery of the IL28 genotype as a potent predictive factor.