Prevalence of occult hepatitis B and hepatitis C virus infections in Turkish hemodialysis patients

BACKGROUND AND OBJECTIVE: Hepatitis B virus (HBV) and hepatitis C virus (HCV) infections are important causes of morbidity and mortality in maintenance hemodialysis patients. Although their exact prevalence is not known, HBV and HCV viral infections and occult viral hepatitis are frequent in these patients. This study aimed to determine the prevalence of occult HBV and HCV infections in maintenance hemodialysis patients. MATERIALS AND METHODS: One hundred and eighty-eight end-stage renal disease patients on maintenance hemodialysis (100 male, mean age 49+/-29 [16-80] years, and mean duration of hemodialysis 98+/-66 [12-228] months) were enrolled in this study. Serological markers for HBV and HCV were determined with immunoenzymatic assay (ELISA) by using commercial diagnostic kits (Access and BioRad, Beckman-Coulter). HCV-RNA (Cobas Amplicor HCV kit) and HBV-DNA (Artus GmbH HBV kit) were determined quantitatively by polymerase chain reaction. RESULTS: Among the patients screened, 25 (13.3%) had HBV infection alone and 38 (20.2%) had HCV infection alone, while seven (3.7%) had dual infection of both viruses. Serological markers for occult hepatitis B and occult hepatitis C were positive in five (2.7%) and nine (4.8%) of the patients, respectively. Isolated anti-HBc was positive in 12 (6.4%) of all patients, three (7.9%) of the patients with anti-HCV and two (40%) of the patients with occult hepatitis B. Isolated anti-HBc positivity was more frequent in patients with occult hepatitis B than in those without (40% [2/5] vs. 5.5% [10/183], p=0.002). None of the patients with HCV had occult hepatitis B. CONCLUSIONS: Both occult and non-occult forms of HCV infection are more prevalent than HBV infection in hemodialysis patients. Especially the patients with isolated anti-HBc positivity should be tested for probable occult hepatitis B infection.     

Infection of hepatitis C virus in patients with chronic renal failure undergoing hemodialysis therapy and staff members]

The prevalence of antibody to hepatitis C virus (anti-HCV) was determined in 564 patients and 145 staff members of nine hemodialysis (HD) units in Nagano Prefecture using an enzyme-linked immunosorbent assay based on the C 100 HCV antigen (the first generation anti-HCV assay). And also serum HBV markers were tested in these subjects. One hundred patients (18%) were anti-C100 HCV positive, indicating that this figure represents a much higher prevalence than that (0.9%) among general population in the same geographical area. Out of 141 patients without history of blood transfusion, 17 (12%) were positive for anti-C 100 HCV, suggesting that blood-transfusions-unrelated acquisition of HCV infection can occur. Anti-HCV prevalence correlated with both the blood units transfused and the duration of HD treatment. There was a significant difference in the prevalence of anti-C 100 HCV in individual dialysis units ranging from 0% to 53%. In the dialysis unit with prevalence of 53%, approximately half of the anti-HCV positive patients were found to have chronic liver disease. The prevalence of hepatitis B virus (HBV) markers among HD patients, on the other hand, was 36% (202/564). Fifty one (51%) of 100 anti-C 100 HCV positive patients and 151 (33%) of 464 anti-C 100 HCV negative patients were positive for HBV markers, with significant difference in HBV infection rate between the 2 groups. The prevalence of chronic liver disease, defined as abnormal serum transaminase levels for more than 6 months was significantly higher in anti-HCV positive patients than in anti-HCV negative ones (39% vs 10%, p less than 0.05), suggesting that HCV infection may contribute to chronic liver disease in HD patients. Among 145 staff members, only 3 (2%) were positive for anti-HCV, whereas 25 (17%) were positive for hepatitis B core antibody (anti-HBc), indicating prior HBV infection. With applying the second generation anti-HCV assay, which can detect antibodies to both capsid and nonstructural products of HCV gene, anti-HCV prevalence increased by two times in HD patients, but didn't change in HD staff members.(ABSTRACT TRUNCATED AT 400 WORDS)     

维持性血液透析患者感染乙型和丙型肝炎的分析

目的为了评价血液透析（血透）患者乙型和丙型肝炎（HBV、HCV）感染状态及对临床情况和肝功能的影响。方法对62例血透患者应用ELISA法和RT-PCR法检测抗-HCV和HCVRNA，采用斑点杂交法和固相放免法检测HBV标志，并检测肝功能和血浆蛋白电泳。结果62例患者中，抗-HCVIgM阳性27例（43．6％），抗-HCVIgG阳性29例（46．8％），HCVRNA阳性34例（54．8％），三项任一项阳性37例（59．7％），5例（8．1％）HBsAg阳性，其中HBeAg和HBVDNA阳性3例。结论向透患者中HCV感染严重，临床情况及预后差，检测血浆蛋白和电泳较肝功能酶学能更好地作为肝炎诊断和反映病情的指标。     

Serologic profile in hepatitis B virus and hepatitis C virus in a Brazilian liver transplant waiting list

Chronic viral hepatitis is currently the most common indication for liver transplantation (OLT). Knowing the serological profile of patients on the liver transplant waiting list (LTWL) is essential to manage prophylactic and therapeutic strategies pre- and post-OLT. The aim of this study was to determine the hepatitis B virus (HBV) and hepatitis C virus (HCV) serological profile on the LTWL. METHODS: Serological data were collected from 44 candidates included on the LTWL from May 2003 to November 2004. HBV and HCV serological profiles were performed by microenzyme immunoassay. RESULTS: Twenty-eight patients (66.7%) lacked HBV serological markers. Anti-HBs was detected in 9.5% and was positive for HBsAg, anti-HBc, IgM anti-HBc, or HbeAg in 4.8% of patients, probably related to reactivation of chronic infection. In 7.1% of patients, the markers demonstrated serological cure of infection. In HCV patients, 41.5% were positive. There was HBV and HCV co-infection in 12.2% of patients. CONCLUSION: HBV infection in 21.4% of the patients corroborates the need to use more efficient protocols for prophylactic and therapeutic management pre- and post-OLT. The high prevalence of HCV infection reinforces the need to follow adequate protocols to avoid related complications and guarantee rational and universal use of more efficient drugs.     

The clinical outcome of hepatitis C virus antibody-positive renal allograft recipients.

In order to investigate the prevalence of antibody to hepatitis C virus (anti-HCV) in renal transplant patients, the evolution of anti-HCV status, and clinical outcome in anti-HCV-positive renal allograft recipients, we tested the sera from 120 renal transplant patients for anti-HCV. Thirty-eight patients were hepatitis B surface antigen (HBsAg)-positive. Two patients were anti-delta-positive. A total of 79 patients (65.8%) had at least one serum positive for anti-HCV. Anti-HCV positivity decreased after transplantation for more than 5 years (65.5% at transplantation versus 37.9%, 78.3 +/- 13.4 months later). Among those with positive anti-HCV, the HBsAg-positive group had significantly higher incidence of chronic hepatitis (50% vs. 25.5%, P = 0.026) and liver cirrhosis (21.4% vs. 0%, P = 0.001) than HBsAg-negative group. Among the 82 HBsAg-negative patients, the prevalence of anti-HCV was significantly higher in those with chronic hepatitis than in those without (86.7% vs. 56.7%, P = 0.027). We conclude from this study: (1) anti-HCV positivity is quite prevalent in renal transplant patients; (2) coinfection of hepatitis B virus (HBV) and hepatitis C virus (HCV) may lead to aggressive liver disease and cirrhosis; HCV infection alone has a more benign clinical outcome; and (3) HCV infection is an important cause of posttransplant chronic hepatitis in HBsAg-negative patients.     

Torque teno virus infection in hemodialysis patients in North India

This study describes the prevalence and association of Torque teno virus (TTV) infection with blood-transmitted viral hepatitis including hepatitis B virus (HBV) and hepatitis C virus (HCV) infections in patients with chronic renal failure (CRF) on maintenance hemodialysis (HD). TTV infection was diagnosed by detection of TTV-DNA in serum, using the polymerase chain reaction (PCR) technique. TTV-DNA was estimated in a total number of one hundred patients with CRF and in 100 voluntary blood donors as controls. The markers of HBV and HCV were also tested in sera samples of these patients. TTV-DNA was detected in 39 of 100 patients (39%) with CRF and in 27 of 100 (27%) healthy controls. The analysis of the results demonstrated HBsAg, IgM anti-HBc, anti-HCV, and HCV core antigen in 5.0, 3.0, 6.0, and 4.0% of patients, respectively. This study could not show any association of TTV with HBV and HCV infections for the transmission pattern or any impact on severity of diseases caused by these viruses in CRF patients. TTV also could not show any association with demographic characteristics of patients, duration of dialysis, number of blood transfusions and renal/liver function of the patients. As such, this study concludes that TTV appears as a benign pathogen, showing no sign of renal/liver damage or any change in the severity of diseases caused by blood-borne hepatitis viruses.     

Incidence of and risk factors for hepatitis B virus and hepatitis C virus infection among haemodialysis and CAPD patients: evidence for environmental transmission

Hepatitis B virus (HBV) serum markers (HBsAg, anti-HBs, anti-HBc)and antihepatitis C antibody (anti-HCV) were prospectively followedin haemodialysis and CAPD patients. From January 1987 to January1990, 185 patients on haemodialysis and 124 on CAPD were analysed.Among patients susceptible to HBV (69 on haemodialysis and 70on CAPD), there were 17 HBsAg seroconversions on haemodialysis(0.19/patient-year) and 1 on CAPD (0.01/patient-year). A Coxproportional hazards model showed that haemodialysis treatmentwas the only risk factor significantly associated with HBV infection,thus suggesting transmission through the environment. Regarding hepatitis C, 83 anti-HCV-negative patients on haemodialysisand 46 on CAPD were followed. There were 18 seroconversionson haemodialysis (0.15/patient-year) and two seroconversionson CAPD (0.03/patient-year). Haemodialysis treatment was alsothe only risk factor significantly associated with a higherrisk of HCV infection. The hazard ratio for HCV infection inhaemodialysis patients was 5.7 compared to CAPD patients. Nevertheless,for one patient on CAPD treatment transfusions were the onlypossible source of HCV infection. In conclusion, both viruses were transmitted mainly throughthe haemodialysis environment, but the role of transfusionscould not be excluded.     

Antibodies against hepatitis C virus among renal transplant patients in Greece

To evaluate the prevalence of hepatitis C virus (HCV) infection in Greek renal transplant (RT) patients and its association with abnormal liver function tests (LFTs), serum anti-HCV was determined (Ortho-ELISA test system) in 206 RT and 245 haemodialysis patients (HD) as controls. The prevalence (10.2%) of anti-HCV in RT patients was significantly higher (P < 0.0001) than in the Greek general population (0.7%) and lower (P < 0.0001) than in the HD patients (23.8%), and was not related to the patients' age, post-transplant time or pre-transplant HD time. None of the anti-HCV RT patients was HBsAg +, whereas 13 (62%) and 12 (57%) of them were anti-HBsAg + and anti-HBc +, respectively. The incidence of abnormal LFTs in anti-HCV + HBsAg ? and anti-HCV ? HBsAg + RT patients was similar. Our findings indicate that: (a) the prevalence of serum anti-HCV in the Greek RT population is high, although considerably lower than in HD pts; (b) anti-HCV + RT patients have a high incidence of abnormal LFTs, comparable to that seen in HBsAg + RT patients; and (c) in a substantial proportion of anti-HCV + RT patients there is evidence of previous HBV infection.     

Prevalence of hepatitis B and hepatitis C in haemodialysis patients

SUMMARY: The prevalence of hepatitis B surface antigen (HBsAg), hepatitis B exposure and antibodies against the hepatitis C virus (anti-HCV) was assessed in 86 haemodialysis patients at the National Kidney and Transplant Institute (NKTI) using the commercial radioimmunoassay and ortho HCV ELISA assay. of the 86 patients included in the study, 42 were male with a mean age of 44.9 years and a mean duration of dialysis of 2.4 years. Forty-four were female with a mean age of 48.4 years and a mean duration of dialysis of 2.3 years. Hepatitis B exposure was 57% and 12.8% of haemodialysis patients were positive for HBsAg, whereas 39.8% of patients were positive for anti-HCV. There was a significant correlation ( P = 0.00007) between anti-HCV positivity and the length of time on haemodialysis. However, there was no significant correlation found between the number of blood transfusions received and anti-HCV positivity. There was also no significant correlation found between HBsAg and antibodies to hepatitis B core antigen (anti-HBc) positivity and the number of blood transfusions or the length of time on haemodialysis, nor between hepatitis B and C exposure and elevated aminotransferase levels.     

Risk of transmission of hepatitis B virus from anti-HBC positive cadaveric organ donors: a collaborative study

Organ donors with a serologic profile of recovered (HBsAg negative and/or anti-HBc IgG positive) hepatitis B virus infection (HBV) have been reported to transmit HBV to recipients. In Italy, up until 2002, anti-HBc determination was not mandatory. We retrospectively evaluated the incidence of HBV transmission among recipients transplanted with organs from anti-HBc positive donors from 1997 to 1999. Anti-HBc was screened in 886 available sera among 964 HBsAg and anti-HCV negative donors. HBV transmission was evaluated in 325 kidney, liver, and heart recipients according to their pretransplant HBV serum profile. Of 210 anti-HBc positive donors, 185 were anti-HBc positive/anti-HBs positive and 25 anti-HBc positive/anti-HBs negative with a prevalence of 20.8% and 2.8%, respectively. One hundred seven sera (51%) were collected from donors after transfusion of blood components, the remainder were either before transfusion or from nontransfused donors. The 210 anti-HBc positive subjects donated 356 kidneys, 117 livers and 117 hearts, among whom follow-up is presently available for 251 kidney, 61 liver, and 25 heart recipients. No HBV transmission was observed independent of the recipient immunological profile among the kidney or heart recipients. In liver recipients, no transmission was reported in recovered or vaccinated patients, while a high incidence (43%) of de novo hepatitis was observed among naive patients. In conclusion, there does not seem to be a risk of transmitting HBV through anti-HBc positive transplants in heart and kidney recipients; only naive liver recipients are at high risk of HBV infection.     

Impact of Hepatitis B and C Virus Infections on Kidney Transplantation: A Single Center Experience

ObjectiveThe impacts of hepatitis C virus (HCV) and hepatitis B virus (HBV) infections on patient and renal graft survivals are controversial. This study sought to evaluate the effects of pretransplantation HCV and HBV infections on renal transplant patients and their grafts at our center.Patients and MethodsWe retrospectively examined 1224 renal transplantations performed between 1992 and 2006, including 28 HBsAg positive; 64, anti-HCV; 9, anti-HCV plus HBsAg positive; and 1123, negative for anti-HCV and HBsAg. The mean posttransplantation follow-up was 5.6 ± 4.1 years.ResultsThe prevalences of HBV infection were 6.2% in 1994 and 2.3% in 2006 and those of HCV infection were 6.8% in 1998 and 5.2% in 2006. The rejection rate was higher among HBV+ (46.4%) and HCV+ (40.6%) groups than the negative groups (31.5%), but it was not significant. There were no significant differences in patient and graft survivals among the groups. The major cause of patient death was liver failure among patients with concomitant HBV+ and HCV+ infections and cardiovascular disease among HCV+ and negative patients.ConclusionsThere has been a decrease in the prevalence of recipients with hepatitis virus infections over the last 15 years. Patient and graft survivals were not affected by HCV or HBV infection.     

Environmental Transmission of Hepatitis B and Hepatitis C Viruses Within the Hemodialysis Unit

Abstract: The hepatitis B virus (HBV) can be transmitted in the dialysis setting through blood transfusions and environmental surfaces. Transfusion related hepatitis C virus (HCV) infection is very well known, but only recently the environmental transmission of this virus was postulated. In order to study the prevalence, mechanisms of transmission, and the ALT patterns of HBV and HCV infections in hemodialysis and CAPD patients before the implementation of HBV vaccination and HCV screening in the blood bank, we conducted a study from January 1987 to January 1990. Sera from 185 hemodialysis and 124 CAPD patients were stored in this period and later analyzed for HBsAg, anti-HBc, anti-HBs, and anti-HCV (second generation ELISA). The prevalence of any HBV marker was 55.7% (103/185) for hemodialysis patients and 31.5% (39/124) for CAPD patients (hemodialysis vs. CAPD, p < 0.001). The prevalence of positive anti-HCV was 35.1% (65/185) for hemodialysis and 33.9% (42/124) for CAPD patients (not significant). There was a significant association between HBV markers positivity and anti-HCV positivity. The multivariate analysis of risk factors revealed an association of the positivity of each virus with the duration of renal replacement therapy (RRT), number of previous blood transfusions, and past history of hemodialysis treatment. Thus, besides the transfusion-related transmission, hemodialysis environmental transmission may also occur for both viruses. The findings of a high prevalence of both viruses and evidence for environmental transmission in the dialysis setting are of major importance for the planning of future preventive measures.     

Serological and vaccination profile of hemodialysis patients during an outbreak of hepatitis B virus infection

During an outbreak of hepatitis B virus (HBV) infection in a hemodialysis unit, patients were assessed for serological viral markers and vaccination status. HBV infection was identified in 26 patients. Twenty of these were positive for hepatitis B surface antigen (HBsAg), and 6 were negative for HBsAg but positive for IgM antibody to hepatitis B core (anti-HBc) and HBV DNA. The primary source of infection was not clearly identified, although 2 patients were suspected to be the index cases. A multiple logistic regression analysis revealed low anti-HBs titers and vaccination status to be independently associated with the risk of acquiring HBV infection. Both the high prevalence of HBV infection (31%) detected in this unit and the low vaccine response (53%) observed reinforce the importance of universal and preventive measures in controlling HBV infection. The detection of HBV DNA in HBsAg-negative/IgM anti-HBc-positive patients emphasizes the value of anti-HBc testing in the routine screening of HBV in hemodialysis units.     

不明原因肝病患者肝组织HBV及HCV抗原的检测及临床和病理特点

目的了解不明原因肝病患者中HBV及HCV隐匿性感染所占的比例及临床、病理特点。方法对31例不明原因肝病患者,采用酶联免疫吸附试验（ELISA）检测血清乙型肝炎病毒标志物（HBV-M）（HBsAg、抗-HBs、HBeAg、抗-HBe和抗-HBc）及丙型肝炎病毒抗体;血清HBV DNA采用荧光定量PCR法检测,HCV RNA采用RT-PCR法检测;应用免疫组织化学二步法检测肝组织中的HBsAg、HBcAg、HCV抗原,并进行常规病理检查。结果肝组织HBV抗原阳性者11例（35.5%）;HBV、HCV抗原均阳性者10例（32.3%）,全阴性者10例（32.3%）。存在HBV隐匿性感染的21例患者中,慢性肝炎患者7例,肝硬化患者12例,肝细胞性肝癌患者2例。结论HBV、HCV感染为不明原因肝病的主要原因,尤其是HBV感染。HBV隐匿性感染与慢性肝炎、肝硬化、肝癌关系密切,应引起重视。     

Prevalence of hepatitis B, hepatitis delta, and human immunodeficiency virus infections in Omani patients with renal diseases.

Patients treated at the Royal Hospital in Oman during January-June 1991 were divided in 3 groups. The 1st group included 103 patients (49 males, 54 females, with a mean of 39 years) who attended the Nephrology Clinic and none of whom were on dialysis. In the 2nd group there were 102 patients (46 males, 56 females, with a mean age of 42 years) on regular hemodialysis (with a mean duration of 35 months) because of end-stage renal failure. The 3rd group comprised 82 kidney transplant patients (44 males, 38 females, with a mean age of 33 years) with a mean duration of prior hemodialysis of 9 months in 80 patients. Blood serum samples from all patients as well as from 134 medical students and 564 blood donors were tested for hepatitis B surface antigen (HBsAg) and hepatitis B core antibody (anti-HBc) by enzyme-linked immunosorbent assay. HBsAg-positive samples were tested for antigen and antibody to hepatitis delta virus (HDV). The prevalence of HBsAg was significantly higher in hemodialysis and renal transplant patients than in nephrology clinic patients (P .05). Previous exposure to HBV was found in 48 of 103 (46.6%) nephrology clinic patients, in 53 of 102 (52%) hemodialysis patients, and in 43 of 82 (52.4%) renal transplant patients. Anti-HBc prevalence rates were significantly lower in medical students (23.1%) and blood donors (27%) than in the patient groups (P .001). In HBsAg-positive subjects HDV infection was found in 1 of 13 (7.7%) patients on dialysis and 2 of 9 (22.2%) kidney transplant recipients who had been transfused in the past. A double infection of HBV and HCV was found only in 4 hemodialysis and 2 transplant patients among 287 patients and 698 healthy subjects tested. Among 5 HIV-infected patients 3 transplant patients seroconverted between 3 and 7 months after kidney transplantation abroad; and 2 hemodialysis patients seroconverted after repeated dialysis and multiple blood transfusions used for kidney transplantation abroad.     

Hepatitis C virus infection in chronic haemodialysis patients, a clinicopathologic study.

Fifty-two patients on regular haemodialysis at our institution were evaluated for the presence of HCV infection. Evaluation included detailed history, clinical examination, and monthly screening for anti-HCV antibody, liver enzymes (ALT, AST), serum iron and ferritin. Also, three-monthly screening for other viral markers, HBV (HBsAg, HBsAb, HBcAb), CMV (IgG and IgM), EBV, and HIV. Anti-HCV antibody was found in 21 patients (40.4%). There was a significant (P less than 0.05) relationship between presence of anti-HCV antibody and proportion of patients who received blood transfusion. During a 12-month follow-up, four (11.4%) patients seroconverted to be Anti-HCV positive while one case (4.8%) seroconverted to be anti-HCV negative. The frequency of elevation of liver enzymes was significantly higher in Anti-HCV positive cases (14/18) than in negative cases (11/28, P = 0.01). Evaluation of liver biopsies of 13 patients showed chronic persistent hepatitis in six and chronic active hepatitis in seven cases. We concluded that hepatitis C is a common problem among chronic haemodialysis patients at our institution; HCV infection is documented in 70% of all clinically diagnosed NANB hepatitis. Presence of anti-HCV antibodies cannot differentiate between active and past infection and cases with early HCV infection can be missed when relying on the mere detection of anti-HCV antibodies.     

Antibodies against hepatitis C virus in hemodialysis patients in the central Italian region of Umbria: evaluation of some risk factors.

The epidemiology of non-A, non-B hepatitis (NANBH) is still incomplete. To define the prevalence of antibodies against the main causative agent of NANBH, the hepatitis C virus (HCV) and the role of some risk factors, we tested sera from 269 patients on chronic dialysis at the hemodialysis units in our region in central Italy. We utilized the recently developed serological assay. Twenty-nine hemodialysis patients (13.3%) and 3 peritoneal dialysis patients (4.8%) were anti-HCV positive. Of these, 13 (40.6%) had antibodies to hepatitis B core antigen (anti-HBc) indicating prior hepatitis B infection. The anti-HCV seropositive patients had been on dialysis longer than the seronegative ones; they had received more transfusions than the others but without a significant difference. The prevalence rate of anti-HCV was statistically significantly higher among hemodialysis patients utilizing the same dialysis equipment for the previous 12 months.     

Prevalence of Occult Hepatitis B and Hepatitis C Virus Infections in Turkish Hemodialysis Patients

Background and Objective. Hepatitis B virus (HBV) and hepatitis C virus (HCV) infections are important causes of morbidity and mortality in maintenance hemodialysis patients. Although their exact prevalence is not known, HBV and HCV viral infections and occult viral hepatitis are frequent in these patients. This study aimed to determine the prevalence of occult HBV and HCV infections in maintenance hemodialysis patients. Materials and Methods. One hundred and eighty-eight end-stage renal disease patients on maintenance hemodialysis (100 male, mean age 49±29 [16–80] years, and mean duration of hemodialysis 98±66 [12–228] months) were enrolled in this study. Serological markers for HBV and HCV were determined with immunoenzymatic assay (ELISA) by using commercial diagnostic kits (Access and BioRad, Beckman-Coulter). HCV-RNA (Cobas Amplicor HCV kit) and HBV-DNA (Artus GmbH HBV kit) were determined quantitatively by polymerase chain reaction. Results. Among the patients screened, 25 (13.3%) had HBV infection alone and 38 (20.2%) had HCV infection alone, while seven (3.7%) had dual infection of both viruses. Serological markers for occult hepatitis B and occult hepatitis C were positive in five (2.7%) and nine (4.8%) of the patients, respectively. Isolated anti-HBc was positive in 12 (6.4%) of all patients, three (7.9%) of the patients with anti-HCV and two (40%) of the patients with occult hepatitis B. Isolated anti-HBc positivity was more frequent in patients with occult hepatitis B than in those without (40% [2/5] vs. 5.5% [10/183], p=0.002). None of the patients with HCV had occult hepatitis B. Conclusions. Both occult and non-occult forms of HCV infection are more prevalent than HBV infection in hemodialysis patients. Especially the patients with isolated anti-HBc positivity should be tested for probable occult hepatitis B infection.