Prevalence of occult hepatitis B virus infection in hemodialysis patients from egypt with or without hepatitis C virus infection

Prevalence of occult hepatitis B virus infection among patients receiving haemodialysis in Sana'a city

BACKGROUND

Occult hepatitis B virus infection (OBI) is a challenging entity. Due to the increase in invasive procedures, blood transfusions, and difficulties in diagnosing OBI, patients are more likely to acquire OBI. This cross-sectional study was conducted to assess the prevalence of OBI by hepatitis B virus (HBV)-DNA detection, the prevalence of HBV infection by total hepatitis B core antibody (HBcAb) detection, and the potential risk factors for HBV infection in patients receiving haemodialysis regularly.

METHODS

This study included 80 patients receiving haemodialysis regularly, without acute or chronic HBV infection. They were selected from the dialysis units in Sana'a city, Yemen from June 2016 to June 2017. Patients who were positive for hepatitis B surface antigen and hepatitis B surface antibody were excluded from this study. Blood samples were taken prior to each haemodialysis session, and serological markers of HBV were included. HBcAb was measured by enzyme-linked immunosorbent assay, and HBV-DNA was measured by polymerase chain reaction.

RESULTS

HBV-DNA was detected in four patients (5%) and HBcAb was detected in 38 patients (47.5%). There was a significant association between HBV-DNA and HBcAb in patients receiving haemodialysis regularly.

CONCLUSIONS

Patients who test positive for HBcAb should undergo additional HBV-DNA testing to allow accurate HBV screening and prevent infection of other patients.

Occult Hepatitis B Infection among Hemodialysis in Tabriz, Northwest of Iran: Prevalence and Mutations within the S Region

Regardless of the extensive screening for the detection of hepatitis B surface antigen (HBsAg), hemodialysis (HD) patients are still severely at the risk of occult hepatitis B virus infection (OBI), especially in developing countries. OBI is defined as the presence of HBV DNA with undetectable HBsAg in the liver and/or Serum. This study aims to determine the prevalence of OBI in HD patients in Tabriz Province, northwest of Iran, and inquire about the mutations in the detected HBsAg. In this cross-sectional descriptive study, ELISA method assessed serum and plasma samples of 118 HBsAg-negative patients undergoing HD treatment for HBV serological markers (HBsAg and Anti-HBc). Specific primers by nested polymerase chain reaction have been utilized to examine HBV DNA; also, direct sequencing of surface genes was carried out to characterize the viral genotypes and S gene mutations. Finally, followed by real-time PCR, the quantity of viral load in OBI-positive patients was determined. A total of 118 HD patients were included (63.6% were male and 36.4% female), with an overall mean age of 60.8 ± 12.8 years old. The prevalence of antihepatitis B core antibody (Anti-HBc) in the study population was 26.3% (31/118). Five patients (4.2%) were positive for HBV DNA and labeled OBI-positive; their plasma HBV-DNA load was less than 100 IU/ml. Following the phylogenetic analysis, the samples with OBI roughly belonged to genotype D, subtype ayw2 and only two had mutations within the S ’gene’s major hydrophilic region (MHR), including T123I, C124F, and P127T. This study reports the prevalence of OBI in the HBsAg-negative HD patients being at a rate of 4.2%, which can be a clinically vital consideration in this region. HBV serologic screening approaches need to be renewed to cover nucleic acid testing in the setting of hemodialysis and all the other high-risk groups associated with it (i.e., blood and organ donors).

Occult Hepatitis (B) Infection in Hepatitis (C) Virus Infection Patients after the Treatment with Direct Acting Antiviral Drugs

Background: The prevalence of occult hepatitis B ranges widely in patients with hepatitis C. This may have an impact on treatment of hepatitis C. Aims: The current study aimed to evaluate the prevalence of occult hepatitis B infection in chronic hepatitis C patients who finished the course of treatment with direct acting antiviral drugs and it’s correlation with treatment failure. Setting: Outpatient Clinic of Internal Medicine Department, Faculty of Medicine, Menoufia University, Egypt. Patients and methods: This study was conducted on 900 Egyptian patients chronically infected with HCV. All patients tested positive for serum real time polymerase chain reaction for HCV- RNA and received DAAs therapy for 12 weeks. Patients were categorized to:  Group I: 450 patients with chronic hepatitis C after direct antiviral treatment who responded to treatment. Group II: 450 patients with chronic hepatitis C after direct antiviral treatment who didn’t respond to treatment. All patients were submitted to clinical examination, laboratory investigations and abdominal ultrasonography. Detection of HBV- DNA and HCV- RNA was performed by PCR. Results: The prevalence of OBI detected in sera of HCV patients was 10.6 % (96/900). The present study showed no significant correlation between prevalence of OBI and virologic failure (p-value: 0.084).  There was no statistically significant difference (p-value > 0.05) between the studied groups as regard prevalence of OBI. Conclusion: The prevalence of OBI was 10.6% in patients chronically infected with HCV. OBI doesn't affect the anti-HCV DAAs outcomes.

Current situation of viral hepatitis in Egypt

An estimated 8-10 million people suffer from viral hepatitis in Egypt. Hepatitis A virus (HAV) and hepatitis E virus (HEV) are the major causes of viral hepatitis in Egypt as 50% or more of the Egyptian population are already exposed to HAV infection by the age of 15. In addition, over 60% of the Egyptian population test seropositive for anti-HEV in the first decade of life. HEV mainly causes self-limiting hepatitis; however, cases of fulminant hepatitis and liver failure were reported in Egypt. Hepatitis B virus (HBV), hepatitis C virus (HCV), and hepatitis D virus (HDV) are the main causes of chronic hepatitis, liver cirrhosis, and liver cancer (hepatocellular carcinoma [HCC]) in Egypt. Globally, Egypt had the highest age-standardized death rate due to cirrhosis from 1990 to 2017. The prevalence rate of HBV (1.3%-1.5%) has declined after national infantile immunization. Coinfection of HBV patients with HDV is common in Egypt because HDV antibodies (IgG) vary in range from 8.3% to 43% among total HBV patients. After the conduction of multiple national programs to control HCV infection, a lower rate of HCV prevalence (4.6%) was recently reported. Data about the incidence of HCV after treatment with direct antiviral agents (DAAs) are lacking. An HCC incidence of 29/1000/year in cirrhotic patients after DAA treatment is reported. A higher rate of infiltrative pattern among HCC patients after DAA treatment is also recognized. Viral hepatitis is one of the major public health concerns in Egypt that needs more attention and funding from health policymakers.

Update on occult hepatitis B virus infection

The event of mutations in the surface antigen gene of hepatitis B virus (HBV) results in undetectable hepatitis B surface antigen with positive/negative anti-hepatitis B core (anti-HBc) antibody status in serum and this phenomenon is named occult hepatitis B infection (OBI). The presence of anti-HBc antibody in serum is an important key for OBI tracking, although about 20% of OBI cases are negative for anti-HBc antibody. The diagnosis of OBI is mainly based on polymerase chain reaction (PCR) and real-time PCR assays. However, real-time PCR is a more reliable method than PCR. OBI is a great issue for the public health problem and a challenge for the clinical entity worldwide. The persistence of OBI may lead to the development of cirrhosis and hepatocellular carcinoma. With regard to OBI complications, the screening of HBV DNA by the highly sensitive molecular means should be implemented for: (1) patients with a previous history of chronic or acute HBV infection; (2) patients co-infected with hepatitis C virus/human immunodeficiency virus; (3) patients undergoing chemotherapy or anti-CD20 therapy; (4) recipients of organ transplant; (5) blood donors; (6) organ transplant donors; (7) thalassemia and hemophilia patients; (8) health care workers; (9) patients with liver related disease (cryptogenic); (10) hemodialysis patients; (11) patients undergoing lamivudine or interferon therapy; and (12) children in time of HBV vaccination especially in highly endemic areas of HBV. Active HBV vaccination should be implemented for the close relatives of patients who are negative for OBI markers. Thus, the goal of this review is to evaluate the rate of OBI with a focus on status of high risk groups in different regions of the world.

Occult hepatitis C virus infection among Egyptian hemodialysis patients

Occult hepatitis C virus (HCV) infection (OCI) was reported in an apparently disease-free state in the absence of liver disease, anti-HCV and HCV-RNA in the serum. The existing data examining the clinical significance of OCI and its potential as a source of HCV infection among hemodialysis patients are very limited. We examined the presence of OCI among patients on maintenance hemodialysis at Minia Governorate, Egypt; an HCV endemic country. A total of 81 subjects with negative markers for HCV were enrolled. HCV-RNA was tested in PBMCs by real-time PCR. For the 81 subjects, the average dialysis duration was 32.7 ± 21.7 months and the average ALT level (±SD) was 26 ± 12 U/L while that of AST was 29 ± 16 U/L. Out of the 81 subjects, three (3.7%) were HCV-RNA positive in PBMCs in the absence of serum anti-HCV and HCV-RNA indicating OCI. The viral load of the OCI subjects ranged from 172 to 4150 IU/ml. History of liver disease was positive in one of the three positive patients. These results highlight the potential risk of HCV transmission from patients within hemodialysis units in Egypt. J. Med. Virol. 88:1388-1393, 2016. © 2016 Wiley Periodicals, Inc.

Prevalence of occult hepatitis B infection in patients visiting tertiary care hospital

BACKGROUND

To study the prevalence of occult hepatitis B virus infection (OBI) in a tertiary care hospital.

METHODS

50 HBsAg negative individuals, each amongst blood donors, alcohol dependence syndrome (ADS), alcoholic cirrhotics, hepatitis C virus (HCV)/cryptogenic cirrhotics, end-stage renal disease (ESRD) on maintenance haemodialysis for one year, all malignancies prior to chemotherapy and HIV positive patients were evaluated for anti-HBc total antibody, and blood hepatitis B virus (HBV) DNA amplification in those tested positive.

RESULTS

A total of 60/369 (16.2%) individuals were anti-HBc total positive, 13/50 (26%) of HCV/cryptogenic cirrhotics, 13/52 (25%) of HIV positive, 10/50 (20%) of patients with malignancy, 10/51 (19.6%) and 7/59 (11.9%) of alcoholic cirrhotics and ADS respectively had intermediate prevalence, while, blood donors 5/55 (9.1%), ESRD patients 2/52 (3.8%) had low prevalence. 12 patients (20% of all anti-HBc total positive cases) were HBV DNA positive, 5 HCV cirrhotics (10% of total HCV/cryptogenic), 4 HIV positive (7.69%), 1 each of ADS (1.69%), alcoholic cirrhotics (1.96%) and malignancy group (2%). Blood donors and ESRD patients were negative for HBV DNA.

CONCLUSION

HBV DNA amplification may under diagnose OBI and anti-HBc total positivity may be a better surrogate marker. Nucleic acid testing of blood donors, however is preferred, especially in high endemic areas. OBI must be looked for in cirrhotics, HIV infection, and patients with cancers prior to chemotherapy, as they may contribute to morbidity in them.

Occult HBV infection status among chronic hepatitis C and hemodialysis patients in Northeastern Egypt: regional and national overview

INTRODUCTION

Occult hepatitis B infection (OBI) is considered to be one of the major risks for patients suffering from end-stage renal disease (ESRD) on regular hemodialysis (HD) and patients with chronic hepatitis C virus (HCV) infection. This study compared the prevalence of OBI among these two high-risk groups in the Suez Canal region, Northeastern Egypt, to obtain a better national overview of the magnitude of OBI in this region.

METHODS

Serum samples were collected from 165 HD patients and 210 chronic HCV-infected patients. Anti-HCV antibody, hepatitis B surface antigen (HBsAg), total hepatitis B core (anti-HBc) antibody, and hepatitis B surface antibody (anti-HBs) were detected by enzyme-linked immunosorbent assay (ELISA). HCV RNA was detected using a quantitative real-time RT-PCR assay, and HBV was detected using a nested PCR.

RESULTS

All patients were negative for HBsAg. A total of 49.1% and 25.2% of the patients in the HD and HCV groups, respectively, were anti-HBc-positive. In addition, more anti-HBs-positive patients were detected in the HD group compared to the HCV group (52.1% and 11.4%, respectively). Three cases were positive for HBV DNA in the HD group, while eighteen positive cases were detected in the HCV group. Both study groups showed significant differences in serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) level as well as anti-HBc, anti-HBs and HBV-DNA positivity.

CONCLUSIONS

OBI was more prevalent among chronic HCV patients than HD patients in the Suez Canal region, Egypt, with rates of 8.5% and 1.8%, respectively. However, more precise assessment of this infection requires regular patient follow-up using HBV DNA detection methods.

Genotyping of occult hepatitis B virus infection in Egyptian hemodialysis patients without hepatitis C virus infection

BACKGROUND

Occult hepatitis B viral infection is the presence of hepatitis B viral nucleic acids in the serum and/or liver in the absence of hepatitis B surface antigen.

AIM

The study aimed to determine the prevalence of occult hepatitis B virus infection among hepatitis C virus-negative hemodialysis patients and to identify their genotypes.

METHODS

of 144 patients on maintenance hemodialysis, 50 hepatitis B surface antigen and hepatitis C virus nucleic acid-negative patients were selected according to strict inclusion criteria to avoid the effect of confounding variables. The following investigations were done: serum AST and ALT; HBsAg; HBcAb; HCV-Ab; HCV-RNA; and HBV-DNA.

RESULTS

Positive hepatitis B viral nucleic acid was confirmed in 12/144 (8.3%) hemodialysis patients and 12/50 (24%) in our study group (occult infection). Mean hemodialysis periods for negative patients and occult hepatitis B virus patients were 27.3±18.8 and 38.4±8.14 months, respectively, and this difference was significant (p-value=0.02). Mean alanine transaminase levels were 20.27±5.5IU/L and 25.3±9.6 in negative patients and occult infection patients, respectively. This difference was non-significant. Aspartate transaminase levels were 21.4±10.2IU/L and 27.3±4.6IU/L, respectively, in negative patients and infected patients; this difference was significant (p-value=0.03). Half (6/12) of the positive samples belonged to genotype 'B', 33.3% (4/12) to 'C', and 16.6% (2/12) to genotype 'D'.

CONCLUSION

OBI is likely among hemodialysis patients even without HCV coinfection (24%). Genotype D cannot be the only genotype distributed in Upper Egypt, as the current study reported relatively new results that 50% of the patients with occult B carry genotype B, 33.3% carry genotype C and only 16.6% carry genotype D.

Occult hepatitis B virus infection among chronic hemodialysis patients in Alexandria, Egypt

The prevalence of end-stage renal disease has increased dramatically in developing countries. Hepatitis B virus (HBV) infection is a global health problem that represents a significant co-morbidity event that has led to outbreaks of hepatitis B. There are inadequate data concerning occult HBV infection among Egyptian chronic hemodialysis patients. This study aimed to detect occult HBV infection among chronic hemodialysis patients in Alexandria, Egypt. A cross-sectional study was performed on 100 patients with end-stage renal disease that received maintenance hemodialysis and had tested negative for HBV surface antigen. Blood samples were collected before the initiation of hemodialysis. Sera were tested for hepatitis C virus (HCV) and hepatitis B core (HBc) antibodies using ELISA, and HBV DNA was detected by SYBR Green real-time PCR using specific primers for the s and c genes and by nested PCR using pol gene-specific primers. The serum activity of alanine and aspartate aminotransferase (ALT and AST) were also measured. Anti-HCV and anti-HBc antibodies were detected in 34% and 48% of patients, respectively, and 70.6% of anti-HCV positive patients were also positive for anti-HBc antibodies. This association was statistically significant (p=0.001). HBV DNA was detected in 32% of the hemodialysis patients. A significant association was determined between the presence of HBV DNA and anti-HCV positivity (p=0.021). Aminotransferases were elevated in 21% of the studied patients, more often in patients with positive anti-HCV profiles than in patients negative for anti-HCV (p<0.05). In conclusion, the serological markers of HBV infection should be verified with molecular tests to investigate possible occult infections, especially among anti-HBc-positive hemodialysis patients, to improve our understanding of their clinical, laboratory, and epidemiological characteristics.

Occult hepatitis B virus infection in hemodialysis patients in Japan

Hepatitis B surface antigen is widely used in hepatitis B virus surveillance; patients who test negative for the antigen are judged to be uninfected. However, occult hepatitis B virus infection has been confirmed with hepatitis B virus DNA at low levels in the liver and peripheral blood in patients positive for hepatitis B core antibody or hepatitis B surface antibody, even if they test negative for hepatitis B surface antigen. To investigate the prevalence of occult hepatitis B virus in hemodialysis patients, we performed cross-sectional analysis of 161 hemodialysis patients in two related institutions for hepatitis B surface antigen, hepatitis B core antibody, and hepatitis B surface antibody. Hepatitis B surface antigen, hepatitis B core antibody, or hepatitis B surface antibody was present in 45 patients (28.0%). Hepatitis B virus DNA was present in six patients (3.7%), all of whom also tested positive for hepatitis B core antibody. Hepatitis B surface antibody positivity was unrelated in only one of the six patients. Four of the six patients were positive for hepatitis B surface antigen; however, two (1.3%) of these with occult hepatitis B virus infection were found to be hepatitis B surface antigen negative. Occult hepatitis B virus infection may be missed in hepatitis B virus surveillance using hepatitis B surface antigen alone; therefore, routine hepatitis B core antibody screening is necessary. Patients who test positive for hepatitis B core antibody should undergo further hepatitis B virus DNA testing to enable accurate hepatitis B virus screening.

Occult hepatitis B virus infection of hemodialysis patients: a cross-sectional study in a hepatitis B virus-endemic region

Occult hepatitis B virus (HBV) infection is defined as the presence of HBV DNA in the liver tissue and/or serum of subjects seronegative for hepatitis B surface antigen (HBsAg). Occult HBV infection of hemodialysis (HD) patients is informative in terms of virus transmission, reactivation after kidney transplantation, and the progression of liver disease. However, there is little detailed information about occult HBV infection in the context of virus endemicity. We tried to investigate the seroprevalence and clinical features of occult HBV infection in HD patients in HBV-endemic regions. We enrolled a total of 159 HD patients and 121 apparently healthy subjects at Dankook University Hospital and Jeju National University Hospital in Korea. HBsAg, anti-HBs, anti-HBc, and anti-hepatitis C virus (HCV) antibody levels were measured by radioimmunoassay. Serum levels of HBV DNA were measured by real-time polymerase chain reaction. The seroprevalence of occult HBV infection was 1.3% in HD patients and 2.5% in the healthy controls. This difference was not significant. The HBV load in all subjects with occult infection was <116 copies/mL, and all were positive for IgG anti-HBc, regardless of the presence of anti-HBs. None of the occult HBV-infected subjects were co-infected with HCV. One of the 2 HD patients with occult HBV infection had no history of blood transfusion. In this HBV-endemic region, the seroprevalence of occult HBV infection in HD patients with a very low viral load was not significantly different from that in apparently healthy subjects.

Occult HBV infection: a faceless enemy in liver cancer development

The hepatitis B virus (HBV) represents a worldwide public health problem; the virus is present in one third of the global population. However, this rate may in fact be higher due to occult hepatitis B virus infection (OBI). This condition is characterized by the presence of the viral genome in the liver of individuals sero-negative for the virus surface antigen (HBsAg). The causes of the absence of HBsAg in serum are unknown, however, mutations have been identified that produce variants not recognized by current immunoassays. Epigenetic and immunological host mechanisms also appear to be involved in HBsAg suppression. Current evidence suggests that OBI maintains its carcinogenic potential, favoring the progression of fibrosis and cirrhosis of the liver. In common with open HBV infection, OBI can contribute to the establishment of hepatocellular carcinoma. Epidemiological data regarding the global prevalence of OBI vary due to the use of detection methods of different sensitivity and specificity. In Latin America, which is considered an area of low prevalence for HBV, diagnostic screening methods using gene amplification tests for confirmation of OBI are not conducted. This prevents determination of the actual prevalence of OBI, highlighting the need for the implementation of cutting edge technology in epidemiological surveillance systems.

Prevalence of occult hepatitis B virus infection in a cohort of HIV-positive patients resident in Sicily, Italy

Occult hepatitis B virus (OBI) in HIV-infected groups is still debated, as well as the associated risk-factors and clinical significance. In this paper, we examined a total of 405 HBsAg-negative/HIV-infected patients enrolled from January 2007 to December 2009. Overall, the prevalence of OBI was 5.9% (95% confidence interval (CI_95%): 3.8–8.7%); it was more frequently associated with “anti-HBc alone” serological marker (11.3%; adjusted odds ratio = 3.7, CI_95%: 1.4–9.8), although it was also detected in the absence of any HBV serological marker (4.9%; CI_95%: 2.3–9.1%). A low prevalence of anti-HCV-positive patients with OBI was found (3.1%; CI_95%: 0.6–8.7%). HIV RNA plasma levels or other immunological/clinical characteristics were not significantly associated with OBI. All but one occult HBV infections were sustained by genotype D viral strains. OBI is relatively frequent in HIV-infected patients, although it does not seem to exert a relevant clinical impact. Viral genotypes in occult HBV infections reflect those circulating in the Mediterranean area.

Hepatitis B virus in the Arab world: where do we stand?

The epidemiology of viral hepatitis is of great importance for planning and managing health provision for all the countries in the Arab world. However, data on viral hepatitis are not readily available in a large percentage of Arab countries. Hepatitis B virus (HBV) is considered to be one of the most important causes of chronic hepatitis, cirrhosis and hepatocellular carcinoma. A systematic electronic search of published literature was conducted to extract data on epidemiology and risk factors for the analysis of HBV infection among the countries in the Arab world. The prevalence of chronic HBV infection was found to be decreasing in some Arab countries although it was still unacceptably high. This was particularly evident in the Arabian Gulf region, in Lebanon, Egypt and Libya. The age-specific prevalence varied from country to country with decline in prevalence being noted among children in the Gulf States and among Libyan women. These declines in prevalence are most likely to be related to the Expanded Immunization Programme. The alarmingly high prevalence of chronically infected patients in some areas and the widespread differences in HBV prevalence between Arab nations may be explained by the variation in risk factors involved. This situation calls for targeted approaches to tackle HBV-related mortality and morbidity. Precise HBV infection prevalence data are needed at the national and the sub-national level to estimate the disease burden, guide health intervention programmes and evaluate vaccine efficiency.

Occult hepatitis B virus infection in patients with chronic hepatitis C treated with antiviral therapy

BACKGROUND

Occult hepatitis B virus infection (OBI) is defined as the presence of hepatitis B virus (HBV) DNA in the liver and/or in the serum of patients with negative results of hepatitis B s antigen (HBsAg) test with or without serological markers of previous viral exposure. The impact of OBI in patients with chronic hepatitis C (CHC) is still unclear.

OBJECTIVES

The Aim of this study was to assess OBI prevalence and its potential implications on treatment outcome in a cohort of patients with CHC underwent standard antiviral therapy.

PATIENTS AND METHODS

Baseline serum samples from 137 HBsAg-negative CHC patients treated with pegylated-interferon and ribavirin (73 Responders/74 Non Responders),were retrospectively analyzed for HBV status.

RESULTS

Seventy-three patients (53.3%) showed markers of previous exposure to HBV. HBV DNA was detected in 2 of 137 serum samples (1.5%), both carrying HBV antibodies. Liver biopsies and post-therapy sera were available for 35 patients (12 Responders/23 Non Responders). HBV DNA sequences were found in 13 of 35 specimens (37.1%), all of patients with HBV DNA negativity in basal and post-therapy serum samples. Among OBI-positive patients, 5 (38.5%) carried serological markers of HBV infection. Regarding therapy outcome, in the OBI-positive group there were 5 of 13 (38.5%) sustained virological responders (SVR) compared to 7 of 22 (31.8%) in the OBI-negative one.

CONCLUSIONS

Despite the high prevalence rate of liver HBV DNA in patients with CHC, SVR was not affected by occult HBV infection.

Hepatitis B and C infection in haemodialysis patients in Libya: prevalence, incidence and risk factors

BACKGROUND

Patients receiving maintenance haemodialysis (HD) are at higher risk for acquiring Hepatitis B Virus (HBV) and Hepatitis C Virus (HCV) infections than the general population. Strict infection control measures are essential to prevent nosocomial transmission. We aimed to investigate the incidence and prevalence of HBV and HCV infection in the HD population of Libya as well as risk factors for infection.

METHODS

All adult patients receiving maintenance HD (n=2382) in Libyan dialysis centres (n=39) were studied between May 2009 and October 2010. Testing for Hepatitis B surface antigen (HBsAg) and anti-HCV antibodies was performed at initiation of dialysis and every 3-6 months thereafter. Patients who were sero-negative for HBV and HCV (n=1160) were followed up for 1 year to detect sero-conversions.

RESULTS

Participant median age was 49 years and 58% were male. 831 patients (34.9%) were sero-positive for HBV and/or HCV (anti-HCV positive 31.1%; HBsAg positive 2.6%; both positive 1.2%). Of the sero-positive patients 4.7% were known to be infected before the initiation of HD. The prevalence of HBV±HCV infection varied widely between HD centres from 0% to 75.9%. Sero-positive patients were younger, had longer time on dialysis and more previous blood transfusions. Prospective follow-up revealed an incidence of sero-conversion of 7.7% during 1 year (7.1% HCV; 0.6% HBV). Wide variation in rates of newly acquired infections was observed between dialysis centres. All new HBV cases were referred from centres already treating HBV infected patients. New HCV infections were reported in most centres but the rate of HCV sero-conversion varied widely from 1.5% to 31%. Duration of dialysis, history of previous renal transplant and history of receiving HD in another centre in Libya were significantly associated with sero-conversion.

CONCLUSION

Patients on maintenance HD in Libya have a high incidence and prevalence of HCV infection and lower rates of HBV infection. The factors associated with HBV and HCV infection are highly suggestive of nosocomial transmission within HD units. Urgent action is required to improve infection control measures in HD centres and to reduce dependence on blood transfusions for the treatment of anaemia.