Seroepidemiology of hepatitis C virus infection in hemodialysis patients and the general population in Fukuoka and Okinawa, Japan

Prevalence of HCV Infection Among Hemodialysis Patients in Lanzhou of Northwestern China

Objective

To investigate the prevalence of hepatitis C virus (HCV) infection among hemodialysis (HD) patients in Lanzhou of Northwestern China, we interviewed 565 patients from five randomly sampled HD centers in Lanzhou with a structured questionnaire including sociodemographic characteristics, past medical history and HD-related factors.

Methods

The testing results of anti-HCV and HCV-RNA in a recent HD from clinical information system were collected. A generalized estimated equation (GEE) logistic regression model was used to identify the determinants of HCV infection among HD patients.

Results

The prevalence of anti-HCV or HCV-RNA infection among HD patients was 1.77% or 1.42% respectively. GEE model showed that history of kidney transplantation (HCV-RNA: OR=19.79, 95%CI: 12.69–30.85) could dramatically increase the risk of current HCV infection in dialysis patients. Compared with never using of blood products, using of blood products (anti-HCV: OR=2.38, 95%CI: 1.22–4.64; HCV-RNA: OR=15.23, 95%CI: 1.79–129.49) could increase the risk of HCV infection in dialysis patients. Moreover, with the increase of HD duration, the risk increased one time or so (anti-HCV: OR=1.83, 95%CI: 1.22–2.72; HCV-RNA: OR=2.00, 95%CI: 1.11–3.61). Furthermore, dialysis in multiple hospitals possessed more than three times risk of HCV infection (anti-HCV: OR=3.56, 95%CI: 3.11–4.08; HCV-RNA: OR=3.35, 95%CI: 1.88–5.96). Besides, HD patients having the history of acupuncture (HCV-RNA: OR=5.56; 95%CI: 1.16–26.67) or surgery (HCV-RNA: OR=6.39; 95%CI: 2.86–14.29) caused an about-six-times risk of current infections.

Conclusion

It could be concluded that the prevalence of HCV infection was mild and using of blood products or kidney transplantation, long dialysis duration, dialysis in multiple hospitals, surgery or acupuncture treatment were some risk factors of HCV infection among HD patients in Lanzhou of Northwestern China.

Hepatitis C virus infection: the new global epidemic

Hepatitis C virus infects an estimated 170 million people worldwide. It is a major cause of liver cirrhosis, end-stage liver disease and hepatocellular carcinoma. It is also a leading cause of liver transplant in the USA. The virus is primarily transmitted parenterally, but there is significant mother-to-child transmission. Partly due to the virus's genetic diversity, it evades the host immune response and it has been difficult to identify candidate vaccines. However, significant advances have been made in the treatment of chronic hepatitis C virus infection. Currently, the combination of pegylated interferon-alpha and ribavirin is the standard treatment for chronic hepatitis C virus infection, and leads to long-term eradication of the virus in approximately 54% of people. Treatment response is dependent on the infecting genotype, with 76 to 80% of those with genotypes 2 and 3, but only approximately 40% with genotype 1 or 4 achieving a sustained virologic response. Since treatment is expensive and associated with significant adverse effects, more effective strategies for the prevention of transmission are needed, especially in resource-limited countries, where the burden of disease is the highest.

A systematic review of hepatitis C virus epidemiology in Asia, Australia and Egypt

BACKGROUND

The hepatitis C pandemic has been systematically studied and characterized in North America and Europe, but this important public health problem has not received equivalent attention in other regions.

AIM

The objective of this systematic review was to characterize hepatitis C virus (HCV) epidemiology in selected countries of Asia, Australia and Egypt, i.e. in a geographical area inhabited by over 40% of the global population.

METHODOLOGY

Data references were identified through indexed journals and non-indexed sources. In this work, 7770 articles were reviewed and 690 were selected based on their relevance.

RESULTS

We estimated that 49.3-64.0 million adults in Asia, Australia and Egypt are anti-HCV positive. China alone has more HCV infections than all of Europe or the Americas. While most countries had prevalence rates from 1 to 2% we documented several with relatively high prevalence rates, including Egypt (15%), Pakistan (4.7%) and Taiwan (4.4%). Nosocomial infection, blood transfusion (before screening) and injection drug use were identified as common risk factors in the region. Genotype 1 was common in Australia, China, Taiwan and other countries in North Asia, while genotype 6 was found in Vietnam and other Southeast Asian countries. In India and Pakistan genotype 3 was predominant, while genotype 4 was found in Middle Eastern countries such as Egypt, Saudi Arabia and Syria.

CONCLUSION

We recommend implementation of surveillance systems to guide effective public health policy that may lead to the eventual curtailment of the spread of this pandemic infection.

Occupational infectious diseases among Korean health care workers compensated with Industrial Accident Compensation Insurance from 1998 to 2004

Using the database of the Korea Labor Welfare Corporation (KLWC), which is the public organization for workers' compensation in Korea, we analyzed the occupational infectious diseases among the health care workers who were compensated by the Industrial Accident Compensation Insurance (IACI). From January 1998 to December 2004, 307 cases of infectious diseases were approved as being cases of occupational diseases. Women accounted for 83% (254 cases) of the compensated cases. The most common age group was 20-29 yr of age (228 cases, 74.3%). The majority of infections were tuberculosis (203 cases, 66.1%), hepatitis (42 cases, 13.7%), chickenpox (11 cases, 3.6%), AIDS (8 cases, 2.6%) and scabies (7 cases, 2.3%). The major types of occupations were nurses, including 18 aid-nurses (223 cases, 72.6%), doctors (37 cases, 12.1%), clinical pathology technicians (18 cases, 5.9%) and workers who were taking care of patients (8 cases, 2.6%). The mean working duration after infection was 3.9 yr and the mean duration of recuperation was 9.7 months. The most common department where the infected workers were working was the inpatient ward (161 cases, 52.4%), followed by the intensive care unit (51 cases, 16.6%). Through this study, we were able to elucidate the characteristics of occupational infectious diseases among Korean health care workers. These results have to be considered when establishing the management policy for prevention of occupational infectious diseases among Korean health care workers. Also, all knowledge from these Korean cases will be helpful to make good practices to promote occupational safety and health in the new era of globalization.

Hepatitis C and kidney disease

Hepatitis C virus (HCV) infection is often associated with kidney diseases such as membranoproliferative glomerulonephritis (MPGN), with and without cryoglobulinemia, membranous glomerulonephritis (MGN) or glomerulosclerosis (FSGN). The aim of our study was to determine the frequency of HCV with or without hypertransaminasemia in patients with chronic nephropathy in the predialytic phase. We tested 340 subjects with chronic renal insufficiency (CRI) from our hospital's nephrology outpatient clinic for anti-HCV antibodies. In positive subjects we tested for HCV RNA by PCR method, monitoring, for at least 4 months, common biohumoral parameters including transaminases (AST, ALT). Of the 340 subjects, 46 (13.5%) were positive for HCV RNA, and 8 of these (17%) showed constant alteration of transaminases. HBsAg was found in 8 of the total study population (2.3%), and none of these showed altered transaminases. Type II diabetes mellitus was found in 26% (12/46) of the HCV-RNA positive patients, and in only 12.5% (37/294) of the negative ones. The kidney diseases we found in the 46 HCV-RNA positive patients were: diabetic nephropathy in 11 (23.9%), MPGN in 7 (15.2%), MPGN + cryoglobulinemia in 2 (4.3%), interstitial nephropathy in 4 (8.7%), IgA mesangial GN in 3 (6.5%), hypertensive nephropathy in 2 (4.3%), focal and segmental GN in 1 (2.2%), urologic disease in 4 (8.7%), other (hematological, genetic, iatrogenic) in 3 (6.6%), unknown in 9 (19.6%). Our data show that the most frequent kidney diseases associated with HCV infection were diabetic related nephropathy and MPGN with and without cryoglobulinemia. HCV infection had a positive association with diabetes. It is interesting to note that in this study population the hepatitis C concomitant to kidney disease was unusually mild: only 4 of the 46 subjects (9%) showed clinical, biohumoral and ultrasound evidence of cirrhosis.

Epidemiology of hepatitis C virus (HCV) infection

Hepatitis C virus remains a large health care burden to the world. Incidence rates across the world fluctuate and are difficult to calculate given the asymptomatic, often latent nature of the disease prior to clinical presentation. Prevalence rates across the world have changed as well with more countries aware of transfusion-related hepatitis C and more and more evidence supporting intravenous drug use as the leading risk factor of spread of the virus. This article reviews current hepatitis C virus prevalence and genotype data and examines the different risk factors associated with the virus.

Hepatitis C virus-associated oral lichen planus: is the geographical heterogeneity related to HLA-DR6?

BACKGROUND

The association between hepatitis C virus (HCV) and oral lichen planus (OLP) is more common in the Mediterranean area and Japan, possibly because of immunogenetic factors.

METHODS

Intermediate-resolution HLA-DRB typing by hybridization with oligonucleotide probes was performed in 31 Italian OLP patients with HCV infection, in 45 Italian OLP and in 48 British OLP patients without HCV infection. As healthy controls we included data from 145 unrelated Italian and 101 unrelated British bone marrow donors.

RESULTS

Italian HCV+ve OLP patients possessed the HLA-DR6 allele more frequently than Italian and British OLP patients without HCV infection (51.6% vs. 17.7% vs. 16.7%; P corrected = 0.028 and 0.017, respectively). There was no difference in the frequency of the HLA-DR6 allele between Italian and British control subjects.

CONCLUSIONS

The present data suggest that HLA-DR6 may be responsible for the peculiar geographic heterogeneity of the association between HCV and OLP.

Oral diseases possibly associated with hepatitis C virus

Morbidity associated with hepatitis C virus (HCV) infection can involve a variety of extrahepatic conditions, including lichen planus (LP) and sialadenitis, predominantly or exclusively involving the oral region, conditions which have been largely neglected in reviews. The literature suggests that HCV-infected patients may frequently have Sjögren-like sialadenitis with mild clinical symptoms, whereas oral LP may be significantly associated with HCV infections in Southern Europe and Japan but not in Northern Europe. These geographical differences could be related to immunogenetic factors such as the HLA-DR6 allele, significantly expressed in Italian patients with OLP and HCV. Analysis of experimental data suggests that HCV could be involved in the pathogenesis of both these diseases. Moreover, parotid lymphoma may arise in patients with sialadenitis, mainly with type II cryoglobulinemia. Little attention has been paid to oral health needs in HCV-infected patients and the variable effect of interferon-alpha therapy on oral tissues. Further research is needed, because of the potentially great influence of oral diseases possibly linked to HCV on the quality of life of millions of patients.

Incidence of Sjögren's syndrome in Japanese patients with hepatitis C virus infection

BACKGROUND AND AIM

Hepatitis viruses induce not only chronic liver diseases but also the impairment of other organs and tissues as extrahepatic manifestations. In particular, hepatitis C virus (HCV) is involved in various extrahepatic manifestations. The purpose of the present study was to evaluate Sjögren's syndrome (SS) and lichen planus (LP) involvement, which are various extrahepatic manifestations in patients with liver diseases related to hepatitis B virus (HBV) or HCV.

METHODS

We examined a total of 110 Japanese patients with chronic liver disease: 29 with HBV infections and 81 HCV infections.

RESULTS

The prevalence of SS according to European and Japanese criteria in patients with chronic HCV infection was significantly higher than in patients with chronic HBV infection (European criteria: 25.9 vs 3.4%; P < 0.05, Japanese criteria: 21.0 vs 3.4%; P = 0.05). Lichen planus was observed in one (3.4%) of 29 patients with chronic HBV infection, and in 11 (13.6%) of 81 patients with chronic HCV infection. Simultaneously combined LP and SS occurred in 8.6% (seven of 81) of patients with HCV infection, but in none with HBV infection.

CONCLUSIONS

Clinicians should routinely follow the HCV-infected patients, paying sufficient attention to the presence of SS and LP, and they should also carefully monitor their prognosis.

Seroepidemiology of TT virus infection and relationship between genotype and liver damage

TT virus (TTV) has been identified in patients with posttransfusion hepatitis of unknown etiology and is thought to be a new hepatitis virus. We determined the extent of TTV infection in the Japanese general population and the relationship between TTV DNA genotype and liver damage. In 1998, we tested 847 serum samples for TTV. TTV DNA was assayed by a nested polymerase chain reaction and classified into three different genotypes and eight subtypes. TTV DNA was detected in 25.3% and 32.4% of the inhabitants of the two areas studied, respectively. The genotype distribution was similar in both areas. G1, G2, and G3 were 60%, 20%, and 5%, respectively. Of the 20 subjects with TTV DNA alone and elevated serum ALT levels, 18 were G1, one was G2, and one was G3. TTV infection is endemic in the Japanese general population studied. The main TTV genotype, G1, may be related to the ensuing liver damage.

HCV: epidemiology, modes of transmission and prevention of spread

Approximately 3% of the world's population has been infected with the hepatitis C virus (HCV), which represents about 170 million chronic carriers at risk of developing serious complications. Following the introduction of screening of blood donors for infection the risk of transmitting HCV by blood products is presently at 1/200,000 units distributed. Intravenous (i.v.) drug users are currently the main risk group with a prevalence rate of about 80% and a yearly incidence varying between 4 and 6%. Vertical and sexual transmissions have also been implicated but data are limited and sometimes controversial. The source of infection for the 30% of cases without an identifiable risk factor remains to be clarified. Prevention of spread includes detailed information of persons at risk of being infected, screening of high-risk populations, strengthening of syringe exchanges among i.v. drug users and strict application of disinfection procedures for all invasive medical equipment.

Second generation hepatitis C virus antibody-positive rate in children: investigation of the route of hepatitis C virus infection in children with no history of transfusion

Hepatitis C virus (HCV) antibody and HCV-RNA screening was undertaken in 1864 children, aged from 0 to 15 years who did not have a history of transfusion. Anti-HCV was tested by the second generation enzyme-linked immunosorbent assay (ELISA). HCV RNA was examined by reverse transcriptase-nested polymerase chain reaction (PCR). Two of the 1864 children were positive for serum HCV RNA. They had no history of transfusion, no episodes of horizontal transmission, but the mother in each case was positive for serum HCV RNA, implying mother-to-infant infection. Eleven children who were positive for HCV antibody with low values and negative for serum HCV RNA were classified as belonging to the high bovine milk (composed primarily of casein)-specific IgG4 value group. This suggested that many of the children who were falsely positive for HCV antibody using ELISA had antibodies to casein.

Routes of transmission of hepatitis C virus in an endemic rural area of Japan. Molecular epidemiologic study of hepatitis C virus infection

We conducted an epidemiological study to investigate the routes of transmission of hepatitis C virus (HCV) infection in an area endemic for HCV. Subjects were the 857 adult inhabitants of K area, Japan. The prevalence of antibody to HCV (anti-HCV) was 26.3%. The HCV genotype 1b was the most prevalent (89.3%) among the anti-HCV positive subjects. Molecular evolutionary analysis, based on the nucleotide sequences of the HCV core region from 23 participants with type 1b, showed that the isolates were distributed into more than 1 group. Multivariate regression analysis demonstrated that an age over 40 years, a history of blood transfusion, the presence of antibody to hepatitis B core antigen (anti-HBc), or a history of surgery were each independently associated with the presence of anti-HCV. No significant differences in the presence of anti-HCV prevalence were observed between the wives of men positive for anti-HCV (33.3%) and age-matched women (36.4%), or between the husbands of women positive for anti-HCV (36.4%) and age-matched men (38.3%), from the same area. Findings suggest that the various strains of HCV type 1b were transmitted via medical procedures, not by the intrafamilial route.

Anti-HCV seroprevalence and risk factors of hepatitis C virus infection in Moroccan population groups

Hepatitis C virus (HCV) seroprevalence and transmission routes were investigated in several groups of the Moroccan population. This study showed a low HCV seroprevalence in the Moroccan general population. However, haemodialysis patients and haemophiliacs were at higher risk of having HCV infection, since the prevalences were, respectively, 35.1 and 42.4% in comparison with the blood donors' prevalence (1.1%). These results indicated that parenteral exposure is the transmission pathway of HCV. To investigate the possibility of vertical HCV transmission, a cohort of healthy, unselected pregnant women were included in the study. A prevalence of 1% was found among them. Seven newborns were anti-HCV-positive, although, when RT-PCR was used to search for HCV RNA in their sera, none of them was viraemic. These data indicated that anti-HCV antibodies were passively acquired in these cases. We concluded that vertical transmission is absent when mothers are at low risk of contracting other parenterally or sexually transmitted diseases. Three percent of a group of patients of a centre for sexually transmitted diseases were repeatedly anti-HCV-positive, suggesting the possible sexual transmission of HCV. When screening 116 sera of anti-HIV-positive subjects, 19.8% were anti-HCV-positive. Furthermore, 17.9% of the sixty-seven patients who were proven to have sexually contracted HIV were also anti-HCV-positive. These data might reflect a likely cotransmission of these two viruses, hence suggesting HIV is a cofacter for HCV sexual transmission, as previously reported.

Lichen planus and hepatitis C virus in the northern Kyushu region of Japan

Oral lichen planus (OLP) is a common oral disorder that manifests a mucosal reaction to a variety of aetiological factors, including liver disorder. This study investigated the relationship between OLP and hepatitis C virus (HCV) infection by studying the prevalence of hepatitis B and C virus infection or liver disease in 45 patients with OLP in the Northern Kyushu region of Japan where the prevalence of HCV infection is the highest in the country. Serum hepatitis B virus surface antigen (HBsAg) was positive in only four patients. Serum anti-HCV or serum HCV RNA was positive in 28 (62%) and 27 (60%) of 45 OLP patients, respectively. The majority (35 of 45, 78%) of OLP patients suffered from liver disease, including chronic hepatitis C (22/45, 49%), HCV-related liver cirrhosis (two), and HCV-related hepatocellular carcinoma (two). These results suggest that HCV is a major cause of OLP.