A preliminary serologic study of hepatitis A virus infection in Japan

Deteriorated outcome of recent patients with acute liver failure and late-onset hepatic failure caused by infection with hepatitis A virus: A subanalysis of patients seen between 1998 and 2015 and enrolled in nationwide surveys in Japan

AIM

A nationwide survey of acute liver failure (ALF) and late-onset hepatic failure (LOHF) has revealed that the outcomes of recent patients whose diseases were caused by infection with hepatitis A virus (HAV) have worsened, compared with those of previously reported patients. The factors associated with this deterioration were evaluated.

METHODS

A total of 83 patients with HAV infection seen between 1998 and 2015 were enrolled. All the patients had a prothrombin time-international normalized ratio of 1.5 or more and hepatic encephalopathy of grade 2 or more severe. The demographic and clinical features of 45 patients seen prior to 2003 (cohort 1) and 38 patients seen during 2004 and thereafter (cohort 2) were compared.

RESULTS

Three and four patients in cohort 1 and cohort 2, respectively, received liver transplantations; the survival rates among the remaining patients were 56% for cohort 2 and 79% for cohort 1 (P < 0.05). The mean age (±standard deviation) of the patients was higher in cohort 2 than in cohort 1 (58 ± 11 vs. 48 ± 13 years; P < 0.01). The percentages of patients with underlying metabolic diseases were 22% in cohort 1 and 61% in cohort 2 (P < 0.01). Diabetic mellitus was more common among deceased patients than among rescued patients (29% vs. 8%; P < 0.05) among patients who did not receive liver transplantations, and a multivariate analysis revealed that patient age and disease type were significantly and independently associated with the outcome.

CONCLUSION

The outcomes of recent patients with ALF or LOHF caused by HAV infection have recently worsened mainly because of an increase in underlying metabolic diseases as a consequence of aging.

Distinct changing profiles of hepatitis A and E virus infection among patients with acute hepatitis, patients on maintenance hemodialysis and healthy individuals in Japan

To compare the epidemiologic profiles of hepatitis A virus (HAV) and hepatitis E virus (HEV) infections in Japan, the prevalence of clinical or subclinical HAV and HEV infections was investigated serologically and molecularly among 128 consecutive patients (age, mean +/- standard deviation, 37.5 +/- 14.7 years) who contracted acute hepatitis between 1989 and 2005 in a city hospital, and among 416 hemodialysis patients (60.1 +/- 12.6 years) and 266 medical staff members (34.6 +/- 11.4 years) at the same hospital, using stored periodic serum samples collected since the start of hemodialysis or employment, respectively. Between 1989 and 1995, among 93 patients with acute hepatitis, 51 (54.8%) were diagnosed with hepatitis A and only one patient with hepatitis E. Between 1996 and 2005, however, among 35 patients, only 3 (8.6%) were diagnosed with hepatitis A and 2 (5.7%) with hepatitis E. Although subclinical HEV infection was recognized in four hemodialysis patients (one each in 1979, 1980, 1988, and 2003) and two medical staff members (1978 and 2003) in previous studies, none of the 191 hemodialysis patients who had been negative for anti-HAV at the start of hemodialysis contracted HAV infection during the observation period of 7.6 +/- 6.4 years. Only one (0.4%) of the 246 medical staff members who had been negative for anti-HAV at the start of employment acquired hepatitis A during the observation period of 7.9 +/- 8.0 years: none had subclinical HAV infection. Clinical or subclinical HEV infection has occurred rarely during the last three decades, while HAV infection has markedly decreased at least since 1996.

Hepatitis A sero-epidemiology in Singapore: a changing pattern

Sera from 896 healthy volunteers between 15 and 56 years old were tested in 1987-1991 for immunoglobulin G antibody against the hepatitis A virus (IgG anti-HAV). The overall seroprevalence rate of IgG anti-HAV was 27%: it increased from 0.9% in the 10-19 years age group to 48.1% in the 40-49 years age group and was 100% in subjects over 50 years. There was no difference in anti-HAV seroprevalence between the sexes (29% among men and 26% among women) and races. A downward trend in anti-HAV seroprevalence was seen from 1987 (33%) to 1991 (21.4%). The level of exposure to the hepatitis A virus has decreased when compared with data obtained in 1975 and 1984-1985. Hepatitis A virus infection is no longer an infection of children and adolescents locally.

The seroepidemiology of hepatitis A and B in a Japanese town

Sera collected from 1,118 healthy children and adults aged between four years and 90 years during the period 1989 to 1990, were tested for serological markers of hepatitis A virus (HAV) [antibody to HAV (anti-HAV)] and hepatitis B virus (HBV) [hepatitis B surface antigen (HBsAg) and antibody to hepatitis B surface antigen (anti-HBsAb)]. The overall prevalence rates of anti-HAV, HBsAg, and anti-HBV were 20.2%, 0.36%, and 5.1%, respectively. No body was found to be positive for anti-HAV below 30 years of age but more than 70% of the adults aged 50 years or over were positive for anti-HAV. The level of exposure of HAV infection is declining in Japan and paradoxically at the same time a vast majority of people are becoming susceptible to more severe illness. The fall in prevalence of HBsAg possibly represents the positive impact of ongoing vaccination programs and other preventive measures against HBV.

Acute hepatitis A, B and non-A, non-B in a Swedish community studied over a ten-year period

985 episodes of hepatitis representing 98% of all acute hepatitis episodes found in a Swedish city during a 10-year period were analyzed for anti-hepatitis A IgM antibodies and hepatitis B surface antigen. Hepatitis A was diagnosed in 311 episodes (32%), hepatitis B in 494 (50%), simultaneous acute hepatitis A and B in 12 (1.2%), and 168 episodes (17%) were classified as hepatitis non-A, non-B. The majority of the hepatitis A cases were drug addicts (58%), and all were concentrated in 3 outbreaks of 1-2 years duration. 16% of all hepatitis A cases were probably imported. Hepatitis B cases decreased significantly (p less than 0.001) between the first and second half of the study period. 47% were drug addicts. Hepatitis non-A, non-B was also dominated by drug addicts (61%). Approximately 20% of the cases in all 3 types of hepatitis had no identifiable source.

Circulating immune complexes in non-A, non-B hepatitis. Possible masking of viral antigen

Serial serum samples from 22 patients with transfusion-associated non-A, non-B hepatitis and 2 chimpanzees with the experimentally induced disease were tested for circulating immune complexes by Raji-cell radioimmunoassay. 13 patients (59%) and 1 chimpanzee had circulating immune complexes immediately before, coincident with, or during the return to normal of raised aminotransferase activity. 7 of the 10 patients with chronic non-A, non-B hepatitis had detectable complexes at levels which waxed and waned in parallel with changes in serum aminotransferase activity. Immune complexes may contain and mask viral antigens, and their presence may explain the failure of conventional immunological techniques to detect virus antigens.