HBV infection is a risk factor for chronic kidney disease: Systematic review and meta-analysis. / La infección por VHB es un factor de riesgo de enfermedad renal crónica: revisión sistemática y metaanálisis.

BACKGROUND: The activity of hepatitis B virus (HBV) as a risk factor for the incidence and progression of chronic kidney disease (CKD) has not been clarified. AIM: We evaluated the impact of infection with HBV on the risk of CKD in the general population. MATERIAL AND METHODS: We carried out a systematic review of the published medical literature to assess whether a relationship between hepatitis B infection and an increased risk of CKD in the adult general population occurs. We adopted the random effects model of DerSimonian and Laird to provide a summary estimate of the risk of chronic kidney disease (defined by lowered glomerular filtration rate and/or detectable proteinuria) with HBV infection across the published studies. Meta-regression and stratified analyses were also performed. RESULTS: We retrieved 33 studies (n=7,849,849 patients) published in 26 different articles, and separate meta-analyses were performed according to the outcome. Pooling results from cohort studies (11 studies, n=1,056,645 patients) demonstrated a relationship between positive HBV serologic status and increased incidence of CKD, the summary estimate for adjusted HR with HBV across the surveys, 1.40 (95% CI, 1.16-1.69) (P<.001). Between-study heterogeneity was noted (Q value, 49.5, P<.0001). No relationship between HBV and prevalence of CKD was noted in the subset of cross-sectional studies (10 studies; n=3,222,545 patients), adjusted OR, 1.04 (95% IC 0.90-1.218; P=.5). Meta-regression analysis reported a relationship between positive HBsAg status and incidence of CKD in the general population (P<.015). CONCLUSIONS: It appears that exposure to HBV infection seems to be associated with an increased risk of developing CKD in the adult general population. Studies aimed to understand the mechanisms responsible of such association are under way.

Meta-analysis of observational studies: hepatitis C and survival after renal transplant.

Recent evidence has shown that anti-HCV-positive serologic status is significantly linked to lower patient and graft survival after renal transplant, but conflicting results have been given on this point. The aim of this study was to conduct a systematic review of the published medical literature concerning the impact of HCV infection on all-cause mortality and graft loss after RT. The relative risk of all-cause mortality and graft loss was regarded as the most reliable outcome end-point. Study-specific relative risks were weighted by the inverse of their variance to obtain fixed- and random-effect pooled estimates for mortality and graft loss with HCV across the published studies. We identified eighteen observational studies involving 133 530 unique renal transplant recipients. The summary estimate for adjusted relative risk (aRR) of all-cause mortality was 1.85 with a 95% confidence interval (CI) of 1.49; 2.31 (P < 0.0001); heterogeneity statistics, Ri = 0.87 (P-value by Q-test = 0.001). The overall estimate for adjusted RR of all-cause graft loss was 1.76 (95% CI, 1.46; 2.11) (P < 0.0001), heterogeneity statistics, Ri = 0.65 (P-value by Q-test = 0.001). Stratified analysis did not change meaningfully these results. Meta-regression showed that living donor rate had a favourable influence on patient (P = 0.031) and graft survival (P = 0.01), whilst diabetes mellitus having a detrimental role on patient survival (P = 0.001). This meta-analysis of observational studies supports the notion that HCV-positive patients after RT have an increased risk of mortality and graft loss. Further studies are in progress to understand better the mechanisms underlying the relationship between HCV and mortality or graft dysfunction after renal transplant.

Antiviral therapy (pegylated interferon and ribavirin) of hepatitis C in dialysis patients: meta-analysis of clinical studies.

Information on the antiviral treatment (pegylated interferon plus ribavirin) of chronic infection by hepatitis C virus (HCV) in patients on long-term dialysis is extremely limited. We evaluated the efficacy and safety of combination antiviral therapy (pegylated interferon plus ribavirin) in patients on long-term dialysis with chronic hepatitis C by performing a systematic review of the literature with a meta-analysis of clinical studies. The primary outcome was sustained virological response (SVR) (as a measure of efficacy); the secondary outcome was dropout rate (as a measure of tolerability). We used the random-effects model of DerSimonian and Laird, with heterogeneity and sensitivity analyses. We identified eleven clinical studies (287 unique patients), two of them being controlled clinical trials. The summary estimate for SVR and dropout rate was 0.60 (95% Confidence Intervals, 0.47; 0.71) and 0.18 (95% CI, 0.08; 0.35), respectively; studies being heterogeneous with regard to both the outcomes. Stratified analysis reported a higher SVR rate in controlled trials, 0.86 (95% CI, 0.27; 0.99). The most common sources of dropout were anaemia (11/46 = 23%) and infections (6/46 = 13%). Meta-regression analysis showed a detrimental impact of HCV genotype 1 (P = 0.036) and dropout (P = 0.0001) rate upon the frequency of SVR. Antiviral therapy based on pegylated interferon plus ribavirin for HCV gives encouraging results in terms of efficacy and safety among patients on long-term dialysis; such approach should be considered the current standard of care for HCV-infected individuals on regular dialysis.

Hepatitis C virus infection and glomerular disease.

The association between hepatitis C virus (HCV) infection and chronic kidney disease (CKD) is well established and remains an area of intense research. HCV infection is associated with a large spectrum of histo-pathological lesions in both native and transplanted kidneys. The frequency of kidney damage in HCV-infected patients appears low even if is not fully detailed. The most frequent HCV-associated renal lesion is type I membrano-proliferative glomerulonephritis, usually in the context of type II mixed cryoglobulinemia. Various approaches have been tried for the treatment of HCV-related glomerulonephritis, including immunosuppressive therapy (corticosteroids and cytotoxic agents), plasma exchange and antiviral agents. Antiviral treatment of HCV-associated glomerulonephritis has shown encouraging results. Immunosuppressive therapy is particularly recommended for cryoglobulinemic kidney disease. Two distinct approaches should be considered for the treatment of HCV-associated cryoglobulinemic glomerulonephritis according to the level of proteinuria and kidney failure. Some evidence on rituximab therapy for HCV-related cryoglobulinemic glomerulonephritis exists but several questions related to its use need to be addressed.

MnSb2O6: a polar magnet with a chiral crystal structure.

Structural and magnetic chiralities are found to coexist in a small group of materials in which they produce intriguing phenomenologies such as the recently discovered Skyrmion phases. Here, we describe a previously unknown manifestation of this interplay in MnSb(2)O(6), a trigonal oxide with a chiral crystal structure. Unlike all other known cases, the MnSb(2)O(6) magnetic structure is based on corotating cycloids rather than helices. The coupling to the structural chirality is provided by a magnetic axial vector, related to the so-called vector chirality. We show that this unique arrangement is the magnetic ground state of the symmetric-exchange Hamiltonian, based on ab initio theoretical calculations of the Heisenberg exchange interactions, and is stabilized by out-of-plane anisotropy. MnSb(2)O(6) is predicted to be multiferroic with a unique ferroelectric switching mechanism.

Interferon therapy of acute hepatitis C in dialysis patients: meta-analysis.

The efficacy and safety of antiviral therapy in patients with acute hepatitis C on long-term dialysis remains unclear, although a number of small clinical studies have been published addressing this issue. We evaluated the efficacy and safety of interferon therapy in chronic dialysis patients with acute hepatitis C by performing a systematic review of the literature with a meta-analysis of clinical studies. The primary outcome was sustained virological response (SVR, as a measure of efficacy); the secondary outcome was dropout rate (as a measure of tolerability). We used the random effects model of DerSimonian and Laird, with heterogeneity and sensitivity analyses. We identified eight clinical studies (173 unique patients), three (37.5%) being controlled clinical trials (CCTs). Among CCTs, the viral response was much more common in study (patients on antiviral therapy) than control (patients who did not receive therapy) groups; the pooled odds ratio of SVR being 27.06, 95% Confidence Intervals (95% CI), 9.26; 79.1 (P = 0.00001). No difference in the dropout rate between study and control patients was shown, odds ratio = 0.920 (95% CI, 0.367; 1.92), NS. Pooling all study results (n = 8 studies) demonstrated that the summary estimate for SVR and dropout rate was 58% (95% CI, 38; 77) and 9% (95% CI, 4; 14), respectively. The most frequent side-effects requiring interruption of the treatment were flu-like symptoms (n = 4, 18%), followed by haematological changes and loss to follow-up. A strong relationship between increasing age and reported dropout rate was recognized (P = 0.001). The studies were heterogeneous with regard to SVR but not to dropout rate. Our meta-analysis of CCTs showed that the viral response after antiviral therapy was more common than the spontaneous viral clearance in dialysis patients with acute hepatitis C. Pooled analysis demonstrated that IFN-based therapy of acute hepatitis C in dialysis populations gives SVR in around one half of patients. These results support IFN-based therapy for acute hepatitis C in patients on maintenance dialysis.

Impact of hepatitis C on survival in dialysis patients: a link with cardiovascular mortality?

Recent evidence has been accumulated showing that anti-HCV-positive serologic status is significantly associated with lower survival in dialysis populations, but the mechanisms underlying this negative relationship are still unclear. The aim of this study was to conduct a systematic review of the published medical literature concerning the impact of hepatitis C virus (HCV) infection on all-cause and disease-specific mortality of patients on regular dialysis. The relative risk of all-cause, cardiovascular and liver disease-related mortality was regarded as the most reliable outcome end-point. Study-specific relative risks were weighted by the inverse of their variance to obtain fixed- and random effect pooled estimates for mortality with HCV across the published studies. We identified fourteen observational studies involving 145 608 unique patients on long-term dialysis. Pooling of study results demonstrated that anti-HCV antibody was an independent and significant risk factor for death in patients on maintenance dialysis. The summary estimate for adjusted relative risk (all-cause mortality) was 1.35 with a 95% confidence interval (CI) of 1.25-1.47. Stratified analysis showed that the adjusted RR for liver disease-related death was 3.82 (95% CI, 1.92; 7.61); heterogeneity statistics, R(i) = 0.58 (P-value by Q-test = 0.087). The adjusted RR for cardiovascular mortality was 1.26 (95% CI, 1.10; 1.45); no heterogeneity was found (NS). This meta-analysis of observational studies indicates that anti-HCV-positive patients on dialysis have an increased risk of either liver or cardiovascular disease-related mortality compared with anti-HCV-negative patients. Further studies are in progress to understand better the link between HCV and cardiovascular risk among patients on maintenance dialysis.

Hepatitis C virus and the immunological response to hepatitis B virus vaccine in dialysis patients: meta-analysis of clinical studies.

It is well known that the seroconversion rate of patients following hepatitis B virus (HBV) vaccination is lower in uraemic than healthy subjects. A variety of inherited or acquired factors have been implicated in this diminished response, and the high prevalence of hepatitis C virus (HCV) infection among patients on maintenance dialysis has been suggested to play a role. However, the impact of HCV on the immune response to HB vaccine in patients receiving long-term dialysis is not entirely understood. Here, we evaluate the influence of HCV infection on the immunological response to HBV vaccine in dialysis population by performing a systematic review of the literature with a meta-analysis of clinical studies.We used the random-effects model of DerSimonian and Laird with heterogeneity and sensitivity analyses. The end-point of interest was the rate of patients showing seroprotective anti-hepatitis B titres at completion of HBV vaccine schedule among HCV-positive versus HCV-negative patients on chronic dialysis. We identified eight studies involving 520 unique patients on long-term dialysis. Aggregation of study results did not show a significant decrease in response rates among HCV-infected versus noninfected patients [pooled odds ratio = 0.621 (95% CI, 0.285; 1.353)]. The P-value was 0.007 for our test of study heterogeneity. Stratified analysis in various subgroups of interest did not meaningfully change our results. Our meta-analysis showed no association between immunological response to hepatitis B vaccine and HCV infection in individuals on long-term dialysis. These results support the use of recombinant vaccine against hepatitis B in patients on regular dialysis with HCV infection.

Combined antiviral therapy of hepatitis C virus in dialysis patients: meta-analysis of clinical trials.

The efficacy and safety of combined interferon (IFN) plus ribavirin in patients on long-term dialysis and chronic hepatitis C remains unclear, although a number of small clinical trials have addressed this issue. We evaluated the efficacy and safety of combination antiviral therapy (conventional or pegylated interferon plus ribavirin) in dialysis patients with chronic hepatitis C by performing a systematic review of the literature with a meta-analysis of clinical trials. The primary outcome was sustained virological response (SVR) (as a measure of efficacy); the secondary outcome was drop-out rate (as a measure of tolerability). We used the random effects model of Der Simonian and Laird, with heterogeneity and sensitivity analyses. We identified 10 clinical studies (151 unique patients), one (10%) of which was a controlled clinical trial. Most (97.4%) patients were on long-term haemodialysis. The summary estimate for SVR and drop-out rate was 56% [95% Confidence Intervals (95% CI) 28-84] and 25% (95% CI, 10-40), respectively. The most frequent side effects requiring interruption of treatment were anaemia (26%) and heart failure (9%). These results occurred irrespective of type of interferon (conventional or peg-IFN, peg-IFNalfa-2a or alfa-2b), trial design (controlled or cohort study), or clinical characteristics of patients (naïve, nonresponders or relapsers). The studies were heterogeneous with regard to SVR and drop-out rate. Combination antiviral therapy (interferon plus ribavirin) gives encouraging results in terms of efficacy and safety among dialysis patients even if the limited number of patients enrolled in our meta-analysis hampers definitive conclusions.

Intradermal vs intramuscular vaccine against hepatitis B infection in dialysis patients: a meta-analysis of randomized trials.

Chronic dialysis patients are at risk of contracting hepatitis B virus infection and have a diminished immune response to hepatitis B virus vaccine. Recent reports support intradermal administration of hepatitis B virus vaccine in patients on regular dialysis but the efficacy and safety of this approach remain unclear. We conducted a meta-analysis of randomized, controlled clinical trials to compare seroprotection achieved by intradermal vs intramuscular hepatitis B vaccine, in patients on maintenance dialysis. Meta-analysis of data from 718 adults (14 trials) on long-term dialysis demonstrated that intramuscular hepatitis B vaccination was less likely to achieve seroprotection than intradermal vaccination, the pooled odds ratio was 0.454 (95% CI, 0.3; 0.67), P = 0.001. The test of study heterogeneity was not significant. This difference did not persist during follow-up (6-60 months after completing vaccine schedule), the pooled odds ratio being 0.718 (95% CI, 0.36; 1.47), NS. Some evidence of significant heterogeneity including publication bias was present but stratified analysis in various subgroups showed that this issue did not meaningfully change our results. Intradermal hepatitis B vaccine was safe and well tolerated. We conclude that intradermal hepatitis B vaccine induces a superior response rate compared to intramuscular route at completion of vaccine cycle, despite a lower vaccine dose. No significant advantage was found over longer follow-up. It remains unclear whether the higher seroprotection rate achieved with intradermal route translates into a lower frequency of de novo hepatitis B among patients on maintenance dialysis.

Viral hepatitis in renal transplantation.

Chronic viral hepatitis remains common in the hemodialysis (HD) and renal transplantation population although measures to limit spread of hepatitis infection in HD units have markedly reduced its prevalence. Our review focuses on the current management of hepatitis B and C infections in renal transplant candidates before and after renal transplantation.

HBV infection is a risk factor for chronic kidney disease: Systematic review and meta-analysis.

BACKGROUND: The activity of hepatitis B virus (HBV) as a risk factor for the incidence and progression of chronic kidney disease (CKD) has not been clarified. AIM: We evaluated the impact of infection with HBV on the risk of CKD in the general population. MATERIAL AND METHODS: We carried out a systematic review of the published medical literature to assess whether a relationship between hepatitis B infection and an increased risk of CKD in the adult general population occurs. We adopted the random effects model of DerSimonian and Laird to provide a summary estimate of the risk of chronic kidney disease (defined by lowered glomerular filtration rate and/or detectable proteinuria) with HBV infection across the published studies. Meta-regression and stratified analyses were also performed. RESULTS: We retrieved 33 studies (n = 7,849,849 patients) published in 26 different articles, and separate meta-analyses were performed according to the outcome. Pooling results from cohort studies (11 studies, n = 1,056,645 patients) demonstrated a relationship between positive HBV serologic status and increased incidence of CKD, the summary estimate for adjusted HR with HBV across the surveys, 1.40 (95% CI, 1.16-1.69) (P < .001). Between-study heterogeneity was noted (Q value, 49.5, P < .0001). No relationship between HBV and prevalence of CKD was noted in the subset of cross-sectional studies (10 studies; n = 3,222,545 patients), adjusted OR, 1.04 (95% IC 0.90-1.218; P = .5). Meta-regression analysis reported a relationship between positive HBsAg status and incidence of CKD in the general population (P < .015). CONCLUSIONS: It appears that exposure to HBV infection seems to be associated with an increased risk of developing CKD in the adult general population. Studies aimed to understand the mechanisms responsible of such association are under way.

Impact of hemodialysis therapy on hepatitis C virus infection: a deeper insight.

Hepatitis C Virus (HCV) infection remains prevalent in patients receiving regular dialysis all over the world. The adverse impact of anti-HCV serologic status on mortality in the dialysis population has been documented. Antiviral therapy for hepatitis C in chronic kidney disease (CKD) patients, including the dialysis population, is still unsatisfactory. Several findings support a different course of HCV in dialysis patients versus the non-uremic population. The HCV viral load appears lower in hemodialysis patients with HCV despite the immune compromise caused by chronic uremia; the histologic abnormalities seem milder, and a severe clinical course of chronic hepatitis C is unusual in most hemodialysis (HD) patients. It appears that the HD procedure per se can preserve patients from an aggressive course of HCV by reducing the viral load (HCV RNA). The mechanisms by which the HD procedure lowers HCV viremia remain largely speculative: the passage of viral particles into the dialysate, the trapping of the virus on the surface of the dialyzer membrane, and an indirect host-mediated mechanism have been cited. The latter hypothesis implicates the production of interferon-alpha, hepatocyte growth factor, or other cytokines provided with antiviral activities during the hemodialysis sessions. Clinical trials aimed at clarifying this issue are under way.

Antiviral therapy of hepatitis C in chronic kidney diseases: meta-analysis of controlled clinical trials.

Hepatitis C virus (HCV) infection remains frequent in patients with chronic kidney disease and the detrimental role of HCV on survival is well-established in this population. Several authors have reported on efficacy and safety of antiviral therapy for hepatitis C in this polulation but there is no clear consensus on management. To evaluate efficacy and safety of antiviral therapy for hepatitis C in patients with chronic kidney disease, we performed a systematic review of the published medical literature and completed a meta-analysis of controlled clinical trials. The primary outcome was sustained virological response (as a measure of efficacy); the secondary outcome was drop-out rate (as a measure of tolerability). We used the random effects model of Der Simonian and Laird, with heterogeneity and sensitivity analyses. We identified 13 studies including 539 unique patients; 10 (76.9%) concerned patients on maintenance dialysis. Only prospective, controlled clinical trials were included. Pooling of study results showed a significant increase of viral response in study (patients treated with antiviral therapy) than control patients (patients who did not receive therapy), the pooled odds ratio (OR) of failure to obtain a sustained viral response was 0.081 [95% confidence intervals (CI), 0.029-0.230], P = 0.0001. The pooled OR of drop-out rate was significantly increased in study vs control patients, OR = 0.389 (95% CI, 0.155-0.957), P = 0.04. The studies were heterogeneous with regard to viral response and drop-out rate. In the subset of clinical trials (n = 6) involving only dialysis patients receiving interferon (IFN) monotherapy for chronic HCV, there was a significant difference in the risk of failure to obtain a sustained viral response (study vs control patients), OR = 0.054 (95% CI, 0.019; 0.150), P = 0.0001 (random-effects model). No significant (NS) heterogeneity was found (Q = 14.604, P = 1.0). No difference in the drop-out rate between study and control patients was shown, OR = 0.920 (95% CI, 0.367; 2.311), NS. This result being homogeneous (Q = 3.639, P = 0.388). Our meta-analysis showed that the viral response was greater in patients with chronic kidney disease who received antiviral therapy than controls. No difference in the drop-out rate between study and control patients occurred in the subgroup of dialysis patients on IFN monotherapy. These results support IFN-based therapy for hepatitis C in patients on maintenance dialysis.

Kinetics of hepatitis B virus load and haemodialysis: a prospective study.

The control of the spread of hepatitis B virus (HBV) infection within dialysis units has been an important goal in the management of patients on regular dialysis but infected patients continue to enter the dialysis system. It is evident that HBV viraemia in hepatitis B surface antigen (HBsAg)-positive patients on dialysis is low but it remains unclear whether haemodialysis per se can contribute to viral load reduction in such patients. HBV DNA was determined in 40 HBsAg-positive patients on maintenance haemodialysis immediately before and at the end of a 4-h haemodialysis session. The same measurements were repeated 48 and 72 h later. Twenty (50%) of 40 HBsAg-positive patients had detectable HBV DNA in serum. Detectable HBV DNA in serum was not predicted by demographic, clinical or biochemical parameters. HBV load decreased in the majority of patients after haemodialysis, although the difference was not significant (29 390 +/- 48 820 vs 23 862.8 +/- 4 350 copies/mL, NS). There was a strong relationship between mean HBV DNA levels before dialysis and absolute reduction of HBV DNA during haemodialysis sessions (r = 0.75, P = 0.0001). No difference occurred in the magnitude of change in HBV DNA titre when comparing cellulosic to synthetic membranes. Haemodialysis per se leads to a reduction in HBV load in HBsAg-chronic carriers on maintenance dialysis. This phenomenon could explain the low viral loads in these patients. Prospective studies are in progress to identify the mechanisms responsible for reduction in HBV load during haemodialysis.

Transmission of hepatitis C virus infection in hemodialysis: current concepts.

A variety of epidemiological data provides evidence for the occurrence of nosocomial transmission of hepatitis C virus (HCV) infection to hemodialysis (HD) patients. The most important factor implicated in HCV transmission between patients treated in the same dialysis unit is cross-contamination from supplies and surfaces as a result of failure of staff to follow infection control procedures. Parts of the HCV genome are highly variable and lend themselves to fingerprinting of each isolate using nucleic acid testing (NAT) and sequencing. This approach has permitted investigation of possible transmission routes within HD units. A systematic review of molecular virology papers revealed transmission of HCV via internal fluid pathways of the dialysis machines in a minority of reports only. Dialyzer reuse was not identified as a risk factor for HCV acquisition in multicenter databases. No randomized controlled trials exist on the impact of isolation on the risk of transmission of HCV to hemodialysis patients. A Belgian prospective multicenter study showed a reduction from 1.4% to 0% in the annual incidence of seroconversion for HCV without any isolation measures, by implementation of strict infection control procedures designed to prevent transmission of blood-borne pathogens, including HCV. However, an isolation policy for HCV-infected dialysis patients should be considered in dialysis units where nosocomial transmission of HCV persists despite reinforcement and audit of hygienic precautions for hemodialysis. Routine audit precautions (general and for dialysis machines) are recommended on a regular basis within HD units.

Hepatitis C virus infection and post-transplant diabetes mellitus among renal transplant patients: a meta-analysis.

OBJECTIVE: To examine the association between HCV infection and the occurrence of post-transplant diabetes mellitus (PTDM) among renal transplant patients. DESIGN: Meta-analysis of observational studies. DATA SOURCES: We retrieved studies published in any language by systematically searching Medline, and Embase and by manually examining the references of the original articles, reviews, and monographs retrieved. REVIEW METHODS: We included cohort and case-control studies reporting relative risk estimates and 95% confidence intervals (CIs) for PTDM occurrence with HCV after renal transplantation. Thirteen studies providing information on a total of 30,099 unique patients were included in our meta-analysis. RESULTS: Study-specific relative risks were weighted by the inverse of their variance to obtain fixed and a 95% confidence interval (CI) of 1.94; 3.83 (10 studies). In a stratified analysis including only large studies (2 studies), the pooled RR was 1.36 (95% CI, 1.21; 1.54). Egger's regression test showed some evidence of publication bias (p=0.0001), but our sensitivity analysis showed that this issue did not meaningfully change the results. CONCLUSIONS: Our study shows a marked increase of the risk of post-transplant diabetes mellitus in anti-hepatitis C virus-positive renal transplant recipients. The excess risk of death in hepatitis C virus-positive renal transplant recipients may be at least partially attributed to post-transplant diabetes mellitus with its attendant complications.

Hepatitis B virus infection in the dialysis population: current perspectives.

One of the major advances in the management of patients on regular dialysis has been the control of the spread of hepatitis B virus (HBV) infection in dialysis units. The rate of HBsAg positive patients on regular dialysis in the developed world is currently low, but outbreaks of HBV continue to occur. The diffusion of HBV in dialysis units in developing countries is higher, although available information is not abundant. There are limited data on the natural history of HBV in the dialysis population; they support a detrimental effect of HBV on survival in dialysis patients. The HBV viral load in HbsAg-positive dialysis patients appears low and stable over time and numerous mechanisms have been posited to explain it. Several assays for detecting HBV DNA in serum are available but they should not be used for purposes of routine screening within dialysis units. The epidemiology and clinical significance of occult HBV infection in the dialysis population needs to be addressed adequately - this remains an area of active research. Recent recommendations for the management of HBsAg chronic carriers on maintenance dialysis have been issued. No controlled trials for the treatment of hepatitis B with either interferon or lamivudine in dialysis patients are currently available.