Usefulness of the Fibrosis-4 index and alanine aminotransferase at 1 year of nucleos(t)ide analog treatment for prediction of hepatocellular carcinoma in chronic hepatitis B patients.

AIM: Nucleos(t)ide analogs do not completely prevent hepatocellular carcinoma (HCC) in chronic hepatitis B virus infection. This study aimed to evaluate the dynamics of a non-invasive liver fibrosis marker, the Fibrosis-4 (FIB-4) index, for predicting HCC development. METHODS: Among a total of 882 chronically hepatitis B virus infection-infected patients who were treated with nucleos(t)ide analogs, 472 patients without HCC history whose FIB-4 at baseline and 1 year of treatment was obtained were evaluated for the incidence of HCC. RESULTS: The median FIB-4 was 2.00 at baseline and was significantly reduced to 1.58 at 1 year (P < 0.001), but the reduction was small at 2 years or later. When a receiver operating characteristic analysis of FIB-4 was performed to predict HCC within 5 years, the area under the curve of FIB-4 at 1 year was higher than that at baseline (0.676 vs. 0.599). The HCC incidence was significantly higher in patients with FIB-4 ≥1.58 than in those with FIB-4 <1.58 (14.8% vs. 3.6% at 10 years, P < 0.001). Additionally, an abnormal alanine aminotransferase (≥31 U/L) at 1 year was an independent risk for HCC. When a fibrosis and alanine aminotransferase-1 (FAL-1) score was evaluated as an applicable number of FIB-4 ≥1.58, and alanine aminotransferase ≥31 as 0, 1, and 2, the HCC risk in patients with score 2 was significantly higher than in those with score 1 or score 0 (24.1% vs. 9.8% vs. 0.7% at 10 years, P < 0.001). CONCLUSIONS: FIB-4 ≥1.58 and alanine aminotransferase ≥31 at 1 year of nucleos(t)ide analog was an independent risk factor for HCC development, and a score using these factors stratified the risk of HCC.

Non-Achievement of Alanine Aminotransferase Normalization Associated with the Risk of Hepatocellular Carcinoma during Nucleos(t)ide Analogue Therapies: A Multicenter Retrospective Study.

Patients with a chronic hepatitis B virus (HBV) infection who are treated with nucleos(t)ide analogues (NAs) are still at risk for hepatocellular carcinoma (HCC), and it has been clinically questioned whether patients with a high risk of HCC can be identified efficiently. We aimed to clarify the risk factors associated with the development of HCC during NA therapies. A total of 611 chronically HBV-infected patients without a history of HCC, who were treated with NAs for more than 6 months (median 72 months), from 2000 to 2021, were included from 16 hospitals in the Tohoku district in Japan. Incidences of HCC occurrence were analyzed with clinical factors, including on-treatment responses. Alanine aminotransferase (ALT) normalization, based on the criteria of three guidelines, was analyzed with other parameters, including the age−male−ALBI−platelets (aMAP) risk score. During the observation period, 48 patients developed HCC, and the cumulative HCC incidence was 10.6% at 10 years. Non-achievement of ALT normalization at 1 year of therapy was mostly associated with HCC development when ALT ≤ 30 U/L was used as the cut-off (cumulative incidence, 19.9% vs. 5.3% at 10 years, p < 0.001). The effectiveness of the aMAP risk score at the start of treatment was validated in this cohort. A combination of an aMAP risk score ≥ 50 and non-achievement of ALT normalization could stratify the risk of HCC significantly, and notably, there was no HCC development in 103 patients without these 2 factors. In conclusion, non-achievement of ALT normalization (≤30 U/L) at 1 year might be useful in predicting HCC during NA therapies and, in combination with the aMAP risk score, could stratify the risk more precisely.

Analysis of microvascular density in early gastric carcinoma using magnifying endoscopy with narrow-band imaging.

BACKGROUND AND STUDY AIMS: Intramucosal vascular density differs between differentiated and undifferentiated type gastric carcinomas. This study aimed to evaluate the microvascular density characteristics of these two types of carcinoma using magnifying endoscopy with narrow-band imaging (ME-NBI). PATIENTS AND METHODS: In total, 42 differentiated and 10 undifferentiated types were evaluated. The microvessels observed using ME-NBI were extracted from stored still images and the microvascular density in the two carcinoma types was analyzed. Histological vascular density in resected specimens was also evaluated using CD34 immunostaining. RESULTS: There were significant differences between the microvascular density in the differentiated and undifferentiated types of carcinoma (10.02 ±â€Š4.72 % vs 4.02 ±â€Š0.40 %; P < 0.001) using ME-NBI. Vascular density assessed histologically also differed significantly between differentiated and undifferentiated types in both the whole mucosal (5.81 ±â€Š3.17 % vs 3.25 ±â€Š1.21 %) and the superficial mucosal layers (0 - 100 µm) (6.38 ±â€Š3.73 % vs 3.66 ±â€Š1.46 %). However, the vascular density in the surrounding non-carcinomatous mucosa assessed using ME-NBI and histologically, was significantly lower in the differentiated than in the undifferentiated types (P < 0.001). There was good agreement between ME-NBI and histologically assessed microvascular density in both the whole (r = 0.740; P < 0.001) and superficial mucosal layers (r = 0.764; P < 0.001). White opaque substance (WOS) was seen in eight patients who had the differentiated type carcinoma. In almost all cases with WOS, the appearance of the carcinoma was discolored. CONCLUSIONS: There was a close relationship between ME-NBI assessed microvascular density and histologically assessed vascular density in the mucosal layer. Microvascular density differed significantly between the differentiated and undifferentiated types of carcinoma assessed using ME-NBI.

The influence of pioglitazone on the plasma amino acid profile in patients with nonalcoholic steatohepatitis (NASH).

BACKGROUND AND AIMS: The peroxisome proliferator-activated receptor-γ (PPAR-γ) ligand, piglitazone, enhances the degradation of branched-chain amino acids (BCAAs) in adipose tissue. However, it remains unknown whether pioglitazone influences the plasma amino acids (AA) profile in patients with nonalcoholic steatohepatitis (NASH). Thus, we investigated the relation between the therapeutic effect and the AA profile in NASH patients with a prospective study. METHODS: We randomized 25 histologically proven NASH patients to diet treatment only or diet treatment plus pioglitazone (15 mg/day), and investigated the biological data for 24 months. We measured the concentrations of AAs and compared them between the beginning and the end of the study. RESULTS: Compared with the diet only group, pioglitazone therapy was associated with an increase in body weight (mean change -1.03 vs. +3.8 kg; p = 0.027) and subcutaneous fat (-3.7 vs. +45.7 cm(2); p = 0.056), and decreased ALT levels (-0.6 vs. -38.4 IU/L; p = 0.029) and HbA1c (0.33 vs. -0.29 %; p = 0.016). Regarding the AA profile, L-isoleucine, L-leucine, L-histidine, and L-lysine were significantly reduced in patients treated with pioglitazone. Furthermore, L-leucine was significantly reduced compared with those in the diet only group (mean change -34.8 vs. +4.12 nmol/mL; p = 0.032). Interestingly, there was a significant correlation between the changes in BCAAs, especially L-leucine, and those in ALT regardless of treatment with pioglitazone. CONCLUSIONS: Pioglitazone therapy in NASH subjects significantly reduced the plasma BCAA level and the degradation was closely related to the improvement of the ALT levels. These results suggest that pioglitazone improves insulin resistance and BCAA metabolism in NASH patients.

Enhanced intracellular retention of a hepatitis B virus strain associated with fulminant hepatitis.

A plasmid carrying 1.3-fold HBV genome was constructed from a HBV strain that caused five consecutive cases of fulminant hepatitis (pBFH2), and HepG2 cells were transfected with pBFH2 or its variants. The pBFH2 construct with A1762T/G1764A, G1862T, and G1896A showed the largest amount of core particle-associated intracellular HBV DNA, but no significant increase of extracellular HBV DNA in comparison with the wild construct, suggesting that these mutations might work together for retention of the replicative intermediates in the cells. The retention might relate to the localization of hepatitis B core antigen (HBcAg) in the nucleus of HepG2, which was observed by confocal fluorescence microscopy. HBcAg immunohistochemical examination of liver tissue samples obtained from the consecutive fulminant hepatitis patients showed stronger staining in the nucleus than acute hepatitis patients. In conclusion, the fulminant HBV strain caused retention of the core particles and the core particle-associated HBV DNA in the cells.

Sporadic acute hepatitis E occurred constantly during the last decade in northeast Japan.

BACKGROUND: Recent studies have shown that indigenous hepatitis E virus (HEV) strains cause hepatitis E in industrialized countries. We aimed to clarify the characteristics of HEV infection in sporadic hepatitis patients during the last decade in Miyagi, northeast Japan. METHODS: We analyzed 94 serum samples obtained from acute or fulminant hepatitis patients of non-A, non-B, and non-C etiology between 1999 and 2008. Antibody to HEV (anti-HEV) was assayed, and patients who were positive for IgM- and/or IgA-class anti-HEV were diagnosed with hepatitis E. HEV RNA was tested in these patients, and phylogenetic analysis was performed. The occurrence of hepatitis E was compared with that of hepatitis A. RESULTS: Eight acute hepatitis patients (8.5%) were diagnosed with hepatitis E, and HEV RNA was detectable in seven patients. Five isolates of HEV were segregated into genotype 3 and the remaining two isolates into genotype 4. The year of the occurrence of hepatitis E was distributed almost equally from 1999 to 2008, whereas the cases of acute hepatitis A (n = 16) have decreased markedly in the last several years. In 2004-2008, the occurrence of hepatitis E was greater than that of hepatitis A (five cases vs. one case). As for seasonality, hepatitis E occurred more frequently from September to December than hepatitis A (five cases vs. four cases), although less frequently from January to April (one case vs. seven cases). CONCLUSION: The occurrence of hepatitis E has not decreased during the last decade in northeast Japan, in contrast to hepatitis A.

Pegylated interferon plus ribavirin for genotype Ib chronic hepatitis C in Japan.

AIM: To evaluate the efficacy of pegylated interferon alpha-2b (peg-IFN alpha-2b) plus ribavirin (RBV) therapy in Japanese patients with chronic hepatitis C (CHC) genotype Ib and a high viral load. METHODS: One hundred and twenty CHC patients (58.3% male) who received peg-IFN alpha-2b plus RBV therapy for 48 wk were enrolled. Sustained virological response (SVR) and clinical parameters were evaluated. RESULTS: One hundred (83.3%) of 120 patients completed 48 wk of treatment. 53 patients (44.3%) achieved SVR. Early virological response (EVR) and end of treatment response (ETR) rates were 50% and 73.3%, respectively. The clinical parameters (SVR vs non-SVR) associated with SVR, ALT (108.4 IU/L vs 74.5 IU/L, P = 0.063), EVR (76.4% vs 16.4%, P < 0.0001), adherence to peg-IFN (>or= 80% of planned dose) at week 12 (48.1% vs 13.6%, P = 0.00036), adherence to peg-IFN at week 48 (54.7% vs 16.2%, P < 0.0001) and adherence to RBV at week 48 (56.1% vs 32.1%, P = 0.0102) were determined using univariate analysis, and EVR and adherence to peg-IFN at week 48 were determined using multivariate analysis. In the older patient group (> 56 years), SVR in females was significantly lower than that in males (17% vs 50%, P = 0.0262). EVR and adherence to Peg-IFN were demonstrated to be the main factors associated with SVR. CONCLUSION: Peg-IFN alpha-2b plus RBV combination therapy demonstrated good tolerability in Japanese patients with CHC and resulted in a SVR rate of 44.3%. Treatment of elderly female patients is still challenging and maintenance of adherence to peg-IFN alpha-2b is important in improving the SVR rate.

A case of HIV co-infected with hepatitis B virus precore/core deletion mutant treated by entecavir.

We report a case of a HIV and hepatitis B virus (HBV)-co-infected patient to whom entecavir (ETV) was administered initially before the notification regarding the potential mutagenesis effect on HIV against the nucleoside analog. Since initial evaluations indicated the advanced stage of chronic hepatitis B and preserved numbers of peripheral CD4+ lymphocytes without the manifestation of immunodeficiency, priority was given to the management of HBV. We started HBV therapy with ETV at a dose of 0.5 mg daily without using any HIV drugs. The viral loads of both HBV and HIV-1 decreased gradually during the 5 months following the initial administration of ETV. HBV was well controlled by the gradual replacement of ETV with highly-active antiretroviral therapy against HIV with a regimen including atazanavir, emtricitabine, and tenofovir. HBV was genotyped as A2 with the quasispecies pool consisting of the -1G precore/core deletion mutant strain.

Analysis of the entire nucleotide sequence of hepatitis B causing consecutive cases of fatal fulminant hepatitis in Miyagi Prefecture Japan.

We encountered five consecutive patients with fulminant hepatitis induced by acute hepatitis B virus (HBV) infection in 2000--2001 in Japan. They had not had previous contact each other, and were referred to us from different hospitals. Although a 69-year-old woman could be rescued by intensive internal treatment, the four patients died. We analyzed the partial (nt 278-646) and entire nucleotide sequences of the HBV obtained from them, and their divergences were 0-0.3% and 0-0.2%, respectively. The results suggested that they had been infected with the same HBV isolates. The isolates belonged to genotype B and subgenotype B2 on the phylogenetic tree analysis (AB302942-AB302946). As for the nucleotides sequences of them, previously reported mutations of G1896A, A1762T, and G1764A were present. Amino acid analysis revealed that previously reported Ile97Leu and Pro130Non-Pro in the core region and Trp28Stop in the precore region were present. As for the entire nucleotide sequences among B2, AB302942 showed low divergences with AF121245 and AB073834 (1.7%), and X97850 from patients with fulminant hepatitis (3.2%). We compared the two consensus nucleotides derived from AB302942 and X97850 (fulminant hepatitis) versus AY121245 and AB073834 (non-fulminant hepatitis), which revealed a difference in nt 1,504 located in the P and X region. Nucleotide 1,504 was C for isolates from fulminant hepatitis and G for non-fulminant hepatitis, and it was recognized among most of the isolates belonging to B2 registered on GenBank. Further studies could disclose the mechanism of severe inflammation of liver that finally leads to fulminant hepatitis.

Analysis of the full-length genome of hepatitis B virus in the serum and cerebrospinal fluid of a patient with acute hepatitis B and transverse myelitis.

Although many extrahepatic manifestations have been described in patients with acute or chronic hepatitis B, there are few reports about neurological disorders. We describe a 55-year-old man who contracted acute hepatitis B virus (HBV) infection and transverse myelitis. His neurological findings were gradually reduced along with the recovery from hepatitis. The cerebrospinal fluid (CSF) was revealed to be positive for HBsAg and HBV DNA. Full-length sequences of HBV in his serum and CSF were determined, and it was revealed that these two isolates had mutations at nucleotide (nt) 1762/1764 in the core promoter region and nt 1896 in the precore region. They were identical to each other except for two ambiguous codes at nt 2020 and 2631 in the CSF isolate. After cloning of the amplicons, substitutions at nt 2020 and 2631 were found in 6 (38%) of the 16 CSF clones. One clone of the 6 CSF clones had an additional substitution at nt 2119. These substitutions were not found in 16 serum clones. The presence of HBV clones unique to CSF suggests that HBV was a possible causative agent of the myelitis.

A case of severe recurrent hepatitis with common variable immunodeficiency.

Severe hepatitis with an indistinct etiology manifested in a 16-year-old boy who had no particular history. The histological features of the liver and clinical course of the patient were similar to those of patients with autoimmune hepatitis characterized by interface hepatitis and severe lobular inflammation of the liver and recurrent exacerbations of hepatitis. We administered intravenous glycyrrhizin preparation daily or three times a week combined with the oral administration of ursodeoxycholic acid daily throughout the term after the initial onset of disease for the control of disease activity. The normalization of the concentration of alanine aminotransferase in serum was achieved in response to the therapy during the course. The serum concentration of immunoglobulins of the patient gradually decreased from the onset of the disease to an unacceptable level without globulin preparation during the following period of 17 months. Immunological tests revealed impairment of immunoglobulin production bythe B cell population of the patient, which led to the diagnosis of the patient as common variable immunodeficiency (CVID). The patient, with improved liver histology after 27 months from the onset of disease, benefited from the current combination therapy without severe infection through the avoidance of overimmunosuppression. CVID is defined as a heterogeneous syndrome characterized by various degrees of hypogammaglobulinemia without any specific predisposing causes, frequently associated with autoimmunity. Diagnostic criteria and therapeutic options of persistent hepatitis with CVID are to be established, as discussed in the current report.

The high incidence of the emergence of entecavir-resistant mutants among patients infected with lamivudine-resistant hepatitis B virus.

Hepatitis B virus (HBV) infection remains to be one of the most prevailing infection in the world, causing chronic liver diseases. Although lamivudine has been effective to suppress HBV replication, longer durations of administration can lead to the emergence of drug-resistant mutant viruses, followed by reactivation of hepatic inflammation (breakthrough hepatitis). Moreover, the optimal period of administration as well as the effects of anti-viral nucleot(s)ide such as lamivudine, adefovir, and entecavir, has not been established. To evaluate the efficacy of the anti-viral effects of entecavir for lamivudine-resistant HBV, we administered entecavir sequentially in four patients with chronic HBV infection, who demonstrated the emergence of lamivudine-resistant HBV and histological active hepatitis. The antiviral effects were evaluated by the serum viral loads and biochemical laboratory data. After follow-up periods of more than 36 months, we found high incidence in the emergence of entecavir resistant mutants (3/4, i.e., 75%). An additional mutation at the 184th amino acid, different from the previously reported lamivudine-resistant mutations (80th, 180th, and 204th), seemed to have a close relationship with the induction of entecavir-resistant mutants at least for Japanese HBV genotype C. Our observation draws attention to the possibility that the usage of entecavir for lamivudine-resistant HBV could promptly induce entecavir-resistant mutations in addition to lamivudine-resistance.

Fulminant hepatic failure in a case of autoimmune hepatitis in hepatitis C during peg-interferon-alpha 2b plus ribavirin treatment.

A 27-year-old Caucasian female with hepatitis C virus (HCV) infection treated with interferon (IFN) who developed severe autoimmune hepatitis (AIH) is described. The infecting viral strain was of genotype Ib and the pre-treatment HCV viral load was at a high level. The patient was treated with pegylated IFN-alpha 2b and ribavirin, and her HCV-RNA became negative at wk 12, but after that she developed fulminant hepatic failure. The patient recovered after steroid pulse therapy consisting of methylprednisolone 1000 mg/d for three days which was administered twice. A needle liver biopsy revealed the typical pathological findings of AIH.

Complete remission of a case of hepatocellular carcinoma with tumor invasion in inferior vena cava and with pulmonary metastasis successfully treated with repeated arterial infusion chemotherapy.

We report the case of a patient having hepatocellular carcinoma with tumor invasion to the inferior vena cava and with multiple pulmonary metastases who was treated with repeated one-shot administration of epirubicin, cisplatin, and mitomycin C by hepatic artery and bronchial artery, which led to complete remission. A 72-year-old woman was diagnosed with infiltrative hepatocellular carcinoma with Vv3, multiple intrahepatic metastases, and multiple pulmonary metastases associated with compensated liver cirrhosis. One-shot infusion of epirubicin, cisplatin, and mitomycin C was performed through proper hepatic artery and bronchial artery for twice at eight weeks of intervals. Pulmonary metastases disappeared and intrahepatic lesions indicated marked shrinkage leaving a scar-like lesion with decreases in tumor markers. After six months and 20 months, tumor markers indicated increasing tendency but no evident recurrence was found by computed tomography or hepatic arteriography. One-shot infusion of the same regimens through proper hepatic artery was performed and tumor markers decreased to normal levels. After 14 months of the last therapy, no evidence of recurrence has been found on image analysis or in tumor markers. This arterial infusion therapy is well tolerated for the patients with compensated liver cirrhosis and might be promising for the effective treatment of advanced hepatocellular carcinoma with pulmonary metastases.

Sustained clinical improvement of a patient with decompensated hepatitis B virus-related cirrhosis after treatment with lamivudine monotherapy.

Hepatitis B virus (HBV) infection, which causes liver cirrhosis and hepatocellular carcinoma, remains a major health problem in Asian countries. Recent development of vaccine for prevention is reported to be successful in reducing the size of chronically infected carriers, although the standard medical therapies have not been established up to now. In this report, we encountered a patient with decompensated HBV-related cirrhosis who exhibited the dramatic improvements after antiviral therapy. The patient was a 50-year-old woman. Previous conventional medical treatments were not effective for this patient, thus this patient had been referred to our hospital. However, the administration of lamivudine, a reverse transcriptase inhibitor, for 23 months dramatically improved her liver severity. During this period, no drug resistant mutant HBV emerged, and the serum HBV-DNA level was continuously suppressed. These virological responses were also maintained even after the antiviral therapy was discontinued. Moreover, both hepatitis B surface antigen and e antigen were observed to have disappeared in this patient. The administration of lamivudine to patients with HBV-related cirrhosis, like our present case, should be considered as an initial medical therapeutic option, especially in countries where liver transplantation is not reliably available.

Sustained viral response of a case of acute hepatitis C virus infection via needle-stick injury.

A 29-year-old nurse with a hepatitis C virus (HCV) infection caused by needle-stick injury was treated with interferon-beta starting about one year after the onset of acute hepatitis. The patient developed acute hepatitis C with symptoms of general fatigues, jaundice, and ascites 4 wk after the needle-stick injury. When these symptoms were presented, the patient was pregnant by artificial insemination. She hoped to continue her pregnancy. After delivery, biochemical liver enzyme returned to normal levels. Nevertheless, HCV RNA was positive and the pathological finding indicated a progression to chronicity. The genotype was 1b with low viral load. Daily intravenous injection of interferon-beta at the dosage of six million units was started and continued for eight weeks. HCV was eradicated without severe adverse effects. In acute hepatitis C, delaying therapy is considered to reduce the efficacy but interferon-beta therapy is one of the useful treatments for hepatitis C infection in chronic phase.

Analysis of the entire nucleotide sequence of hepatitis B virus genotype B in the Philippines reveals a new subgenotype of genotype B.

The entire nucleotide sequences were determined for hepatitis B virus (HBV) genotype B (HBV/B) genomes extracted from five patients in the Philippines and designated GenBank AB219426, AB219427, AB219428, AB219429 and AB219430. The serotype of the first four isolates was ayw and that of GenBank AB219430 was adw. Divergences of entire sequences were 1.0-2.0 % between the first four isolates and 3.8-4.2 % between these four and GenBank AB219430. Phylogenetic-tree analysis revealed that, worldwide, HBV/B comprises five subgenotypes: B1, B2, B3, B4 and the new Philippines group, designated B5. Divergences of the entire genome sequences between four isolates in subgenotype B5 and isolates from other countries (subgenotypes) were 4.4-4.8 % with Vietnam (B4), 2.9-3.5 % with Indonesia (B3), 4.7-5.1 % with China (B2) and 5.4-6.0 % with Japan (B1). Similarly, GenBank AB219430 showed the lowest divergences: 3.4 % with the isolate from Indonesia (B3), 5.0 % with Vietnam (B4), 5.4 % with China (B2) and 6.1 % with Japan (B1). This is the first report of entire nucleotide sequences of HBV/B from the Philippines and the results show that these sequences belong to a new subgenotype, B5. The present study identified that HBV/B isolates throughout the world are divided genetically into five subgenotypes, the relationships between geographical distances and the genetic distances of HBV/B being well-correlated.

A case of acute hepatitis with positive autoantibodies who actually had hepatitis E virus infection.

Hepatitis E virus (HEV) is one of the major causative agents of acute hepatitis in many developing countries. On the other hand, recent intensive investigation has revealed the existence of non-imported cases in industrialized countries. We encountered a sporadic patient with hepatitis E in 1999, who had had no recent travel abroad. He was a 67-year-old Japanese, and his laboratory data were negative for serum markers of hepatitis A, B and C virus infection and positive anti-nuclear antibody, anti-smooth muscle antibody and high level of serum immunoglobulin G. He scored as probable autoimmune hepatitis (AIH) with the scoring system by the international AIH group. He was given a diagnosis of acute cryptogenic hepatitis including acute onset AIH in those days, but the recent retrospective examination with frozen stocked serum revealed his exact diagnosis. In conclusion, we must take HEV infection into consideration for the diagnosis of cryptogenic acute hepatitis even in the developed countries, and some patients with hepatitis E could demonstrate positive for autoantibodies similar to clinical features of AIH. This case demonstrated the needs for further studies about clinical feature of acute hepatitis E virus infection.

A patient with clinical features of acute hepatitis E viral infection and autoimmune hepatitis.

Hepatitis E virus (HEV) is one of the major causative agents of acute hepatitis in many developing countries. Recent intensive examination has revealed the existence of non-imported cases in industrialized countries. The patient was a 25-year-old Japanese female with acute hepatitis. Laboratory test demonstrated positive anti-nuclear antibody (ANA), anti-smooth muscle antibody (ASMA) and high level of serum immunoglobulin G (IgG). The patient was negative for serum markers of hepatitis A, B or C virus infection. She demonstrated a clinical course similar to severe autoimmune hepatitis, including response to prednisolone therapy. After a few years, with the availability of tests for the serum antibodies to HEV, we examined the frozen stocked sera of the patient and found her exact diagnosis was acute hepatitis E. Although we could not detect HEV-RNA, which is positive only in limited period of acute phase, serum IgA and IgG antibodies to HEV were positive and the titer of IgA and IgG antibodies were declined with the time course. In conclusion, we must take into consideration of HEV infection for the diagnosis of acute cryptogenic hepatitis including autoimmune hepatitis. Further studies are feasible to understand the pathogenesis of liver injuries induced by HEV infections.