Hepatitis B virus infection in chronic uremia: long-term follow-up of a two-step integrated protocol of vaccination

Robust hepatitis B vaccine-reactive T cell responses in failed humoral immunity

While virus-specific antibodies are broadly recognized as correlates of protection, virus-specific T cells are important for direct clearance of infected cells. Failure to generate hepatitis B virus (HBV)-specific antibodies is well-known in patients with end-stage renal disease. However, whether and to what extent HBV-specific cellular immunity is altered in this population and how it influences humoral immunity is not clear. To address it, we analyzed HBV-reactive T cells and antibodies in hemodialysis patients post vaccination. 29 hemodialysis patients and 10 healthy controls were enrolled in a cross-sectional study. Using multiparameter flow cytometry, HBV-reactive T cells were analyzed and functionally dissected based on granzyme B, interferon-γ (IFN-γ), tumor necrosis factor alpha (TNF-α), interleukin-2 (IL-2), and IL-4 expression. Importantly, HBV-reactive CD4⁺ T cells were detected not only in all patients with sufficient titers but also in 70% of non-responders. Furthermore, a correlation between the magnitude of HBV-reactive CD4⁺ T cells and post-vaccination titers was observed. In summary, our data showed that HBV-reactive polyfunctional T cells were present in the majority of hemodialysis patients even if humoral immunity failed. Further studies are required to confirm their in vivo antiviral capacity. The ability to induce vaccine-reactive T cells paves new ways for improved vaccination and therapy protocols.

Clinical practice guideline management of blood borne viruses within the haemodialysis unit

Some people who are receiving dialysis treatment have virus infection such as hepatitis B, hepatitis C and/or HIV that is present in their blood. These infections can be transmitted to other patients if blood is contaminated by the blood of another with a viral infection. Haemodialysis is performed by passing blood from a patient through a dialysis machine, and multiple patients receive dialysis within a dialysis unit. Therefore, there is a risk that these viruses may be transmitted around the dialysis session. This documents sets out recommendations for minimising this risk.There are sections describing how machines and equipment should be cleaned between patients. There are also recommendations for dialysing patients with hepatitis B away from patients who do not have hepatitis B. Patients should be immunised against hepatitis B, ideally before starting dialysis if this is possible. There are guidelines on how and when to do this, for checking whether immunisation is effective, and for administering booster doses of vaccine. Finally there is a section on the measures that should be taken if a patient receiving dialysis is identified as having a new infection of hepatitis B, hepatitis C or HIV.

Lower Long-term Efficiency of Intradermal Hepatitis b Vaccine Compared to the Intramuscular Route in Hemodialysis Patients

Intramuscular (IM) and Intradermal (ID) vaccination against hepatitis B (HB) are efficient in hemodialysis patients. We retrospectively analysed the response of 32 patients during 48 consecutive months and compared the results of the two vaccination routes using the recombinant vaccine (Engerix, SKB).

Thirteen patients were vaccinated with 5 mcg ID every 2 weeks (total 8 doses), plus an IM dose on month (M) 12 (group A). Nineteen patients (group B) were vaccinated with 4 IM doses of 20 mcg each, on months M0, 1, 2 and 12.

HB antibodies were measured on M5, M11, M13, M24, M36 and M48. An additional 20 mcg IM dose was given with titers below 10 mIU/ml. Seroconversion, seroprotection and antibody levels were equivalent in both groups up to M13; with the exception of seroconversion rates, a significantly different response was observed afterwards (A/B, in mIU/ml): M5: 399 ± 107 vs 342 ± 69, M13: 536 ± 118 vs 673 ± 61, M24: 278 ± 94 vs 595 ± 81, P=0.02, and M48: 68 ± 29 vs 565 ± 92, P=0.003. Early HBSAB levels did not correlate with those found four years later in both groups. An additional booster dose was given 8 times in 4 group A patients (1–3 doses/patient) and 3 times in 1 group B patient.

Immune response to HB vaccine in hemodialysis patients is initially equivalent by both immunization routes. Late antibody titers were found significantly lower in ID immunization with more frequent booster doses needed.

Spectrum of hepatitis B and renal involvement

Renal involvement in hepatitis B occurs in various spectrums and its knowledge is important for clinicians in management of patients. The renal diseases most commonly associated with hepatitis B virus (HBV) infection include membranous nephropathy, membranoproliferative glomerulonephritis and Polyarteritis nodosa. The widespread use of hepatitis B vaccination has decreased the incidence of HBV-related renal diseases. The incidence of HBV infection in dialysis patients has significantly decreased over the past few decades because of screening of blood products for hepatitis B surface antigen (HBsAg) and hepatitis B core antibody, implementation of infection control measures and hepatitis B vaccination. The definition of acute kidney injury has been recently modified in cirrhotic population, helping in prognosis and prediction of mortality. The most common etiologies of acute kidney injury in this cirrhotic population, which account for 80% to 90% of all cases, include volume depletion, acute tubular necrosis and hepatorenal syndrome. Treatment with oral nucleoside/tide analogues (NA) brought a new paradigm in the management of HBsAg positive glomerulonephritis, kidney transplant recipients and dialysis patients, resulting in effective viral suppression, reduced hepatic complications and improved patient survival, without compromising renal allograft outcome. NAs are cleared by the kidneys and therefore their dosage has to be adjusted in all patients with impaired renal function. This article reviews the recent knowledge of the pathogenesis and treatment of HBV-related glomerulonephritis and discusses the management of hepatitis B in patients on dialysis, kidney transplant recipients and cirrhotics, which is continuously evolving.

Immunogenicity of Human Papillomavirus Recombinant Vaccine in Children with CKD

BACKGROUND AND OBJECTIVES

There is a disproportionate burden of human papillomavirus (HPV) -related genital tract disease in patients with CKD and kidney transplantation; therefore, the potential effect of the quadrivalent HPV vaccine (Gardasil; Merck GmbH, Darmstadt, Germany) is profound. Immune abnormalities associated with CKD and immunosuppression may prevent optimal vaccine response. Our objective was to determine antibody response to the HPV vaccine in adolescent girls with CKD.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

This cohort study conducted from 2008 to 2012 included 57 girls aged 9-21 years old with CKD (n=25), on dialysis (n=9), or with status postkidney transplantation (n=23) who received the standard three-dose vaccine series of the HPV vaccine recruited from two pediatric nephrology clinics. Antibody levels to HPV genotypes 6, 11, 16, and 18 were measured before vaccine dose 1 (baseline), <12 months after vaccine dose 3 (blood draw 2), and ≥12 months after vaccine dose 3 (blood draw 3). Seropositivity was defined as antibody level above an established threshold for each HPV genotype. Not all participants completed three blood draws.

RESULTS

Antibody response to all four HPV genotypes was 100% in the CKD and dialysis groups with samples drawn at <12 and ≥12 months after dose 3 of the HPV vaccine. Among patients with transplants, the percentages of patients achieving seropositivity were significantly lower at blood draw 2 for HPV genotypes 6 (63.6%; P=0.003), 11 (63.6%; P=0.003), and 18 (72.7%; P=0.02) and blood draw 3 for HPV genotypes 6 (62.5%; P=0.02), 11 (50%; P=0.001), 16 (75%; P=0.04), and 18 (50%; P=0.001).

CONCLUSIONS

Antibody response to the quadrivalent recombinant HPV vaccine was robust and sustained in girls and young women with CKD and on dialysis. A less robust response to the vaccine was observed among those with a kidney transplant. Additional study is needed to determine if vaccination before kidney transplantation or an alternative vaccination regimen would benefit transplant recipients.

Novel Perspectives on the Hepatitis B Virus Vaccine in the Chronic Kidney Disease Population

Background

The prevalence and incidence rates of hepatitis B virus (HBV) among patients undergoing maintenance dialysis in developed countries have declined over the last 2 decades thanks to the implementation of numerous infection control procedures in dialysis units, including the hepatitis B vaccine. It is well known that the immune response against HBV vaccine is unsatisfactory in the chronic kidney disease (CKD) population. The seroprotection rate after the HB vaccine schedule is low and the anti-HB titers are reduced, falling logarithmically over time.

Purpose

We did an extensive review of the medical literature on the mechanisms underlying the reduced response rate towards the HBV vaccine in patients with CKD. The efficacy and safety of HBV vaccines for use in the CKD population was also evaluated.

Results

Currently available vaccines against HBV are mostly plasma-derived or manufactured by recombinant DNA technology (yielding the S protein of the HBV envelope). The most promising strategy to enhance the immune response toward the HBV vaccine in the dialysis population is given by adjuvanted vaccines. Second-generation recombinant HB vaccines provided with a novel adjuvant (AS04, made of 3- O-4′-desacyl-monophosphoryl lipid A adsorbed on aluminum phosphate) demonstrated improved immunogenicity but a number of patients with an unsatisfactory response still occurs. Additional second-generation vaccines containing nonaluminum-based adjuvant systems such as AS02 (3- O-desacyl-4′-monophoshoryl lipid A and QS21) or 1018 (a Toll-like receptor 9 agonist) have shown higher immunogenicity and acceptable safety in the CKD population. The evidence in patients with end-stage renal disease is extremely limited on the use of third-generation vaccines, recombinant HBV vaccines expressed in mammalian cells containing S/Pre-S antigens.

Conclusions

The immunogenicity of HBV vaccines in patients with CKD is suboptimal but novel technologies promise to give better results in the near future.

A randomized pilot trial on the effect of granulocyte-colony stimulating factor on antibody response in hemodialysis patients who had not responded to routine hepatitis B virus vaccine

BACKGROUND

Various strategies have been applied to improve the response to hepatitis B virus (HBV) vaccination in hemodialysis patients.

OBJECTIVES

The present study was under taken to compare the seroconversion rate of hemodialysis patients who had not respond to 3 intramuscular (IM) doses (40 μg each) of HBV vaccine , after a fourth IM dose (40 μg) of HBV vaccine that was administered alone or with subcutaneous granulocyte-colony stimulating factor (G-CSF) (5 μg/kg).

PATIENTS AND METHODS

Twenty six hemodialysis patients who had not responded to 3 IM injections of HBV vaccine were randomized into 2 groups: Group 1 received a booster dose of 40 μg HBV vaccine IM, group 2 received a booster dose of 40 μg HBV vaccine IM plus 5 μg/kg subcutaneous G-CSF. Antibody to hepatitis B surface antigen was measured 1 month after the booster dose.

RESULTS

Seroconversion rate in group 1 was 40%. There was a trend towards a higher seroconversion rate at 60% in group 2 patients; however, because of the small number of patients it did not reach statistical significance.

CONCLUSIONS

Larger number of patients and other innovative strategies should be applied for vaccination of this group of patients. More prolonged follow up of the patients is needed to evaluate the duration of protection induced by each method of vaccination.

Varicella zoster virus: vaccination and implications in children with renal failure

The varicella zoster virus is associated with significant disease in those with chronic kidney disease, both pre- and postrenal transplantation. With the advent of the varicella vaccine, the opportunity to prevent significant morbidity and mortality exists. Despite the secondary immune defects associated with renal failure, the varicella vaccine has been demonstrated to be immunogenic, safe and efficacious in pediatric patients with kidney disease.

The potential of 1018 ISS adjuvant in hepatitis B vaccines: HEPLISAV™ review

Hepatitis B (HBV) virus infects the liver, and upon chronic infection, can cause liver cirrhosis and hepatocellular carcinoma. Despite universal vaccination programs against the virus, HBV still affects over 2 billion people worldwide, with over 240 million developing a chronic infection. While current alum-adjuvanted vaccines have shown efficacy in promoting seroprotection in healthy adults, 5-10% of immune-competent populations fail to achieve long-lasting seroprotection from these formulations. Furthermore, a large proportion of immunocompromised patients fail to achieve seroprotective antibody titers after receiving these vaccines. A novel vaccine candidate, HEPLISAV™, uses immunostimulatory sequences (ISS), in its formulation that helps induce a robust humoral and cell mediated immunity against HBV. In Phase III clinical trials, HEPLISAV™ has been shown to elicit seroprotective antibody titers with fewer immunizations. Similar safety profiles are demonstrated when compared with current HBV vaccines. For these reasons, HEPLISAV™ is an attractive vaccine to combat this global disease.

Hepatitis B vaccination in chronic kidney disease: review of evidence in non-dialyzed patients

CONTEXT

Hepatitis B vaccination of hemodialysis patients is performed all over the world. There are also recommendations from world health organizations to vaccinate patients with chronic kidney disease (CKD) prior dialysis commencement, but the implementation of a hepatitis B vaccination program is less common and not well organized.

EVIDENCE ACQUISITION

This review article summarizes data indicating why, when and how to vaccinate CKD patients before they start renal replacement therapy. Publication for this review was bringing into being from PubMed.

RESULTS

There is an agreement in the nephrological societies and among clinicians and scientists that CKD patients should be vaccinated in early stages of their disease, because a higher glomerular filtration rate is more likely to be associated with the responsiveness to vaccination. Schedules of vaccination and optimal vaccine doses are still being investigated. Differences in data with respect to these problems may result from comparisons of various vaccine doses and vaccination schedules without reference to one gold standard, variations in patients` clinical status and glomerular filtration rate, and also the small groups of the affected patients make statistical analysis non-conclusive. A titer of antibodies to surface antigen of hepatitis B virus (anti-HBs) > 10 IU/L or ≥ 10 IU/L is commonly considered as a marker of seroconversion to anti-HBs positivity after vaccination in both non-dialyzed and dialyzed patients. In advanced CKD, vaccine-induced serconversion rate is seldom observed in more than 90% of vaccinees. Various strategies have been utilized in order to increase vaccine-induced seroconversion rate in patients with advanced CKD. Changing the injection mode, the use of adjuvants and immunostimulants to improve the immunogenicity of existing recombinant hepatitis B vaccines, introduction of mammalian-cell derived pre-S/S HBV vaccines (third-generation vaccines) were tried in order to improve the immunization rate.

CONCLUSIONS

There are a substantial number of non-responders to the hepatitis B vaccine among CKD patients. Therefore, successful prevention of hepatitis B virus transmission and spread will only be attained when hepatitis B vaccination is applied together with full implementation of appropriate infection control procedures.

Erythropoietin use and immunogenicity of hepatitis B virus vaccine in chronic kidney disease patients: a meta-analysis

BACKGROUND

It is known that the immunogenicity of hepatitis B virus (HBV) vaccine is lower in uremic patients than healthy subjects. Numerous inherited or acquired factors have been implicated in this lowered response, and the high frequency of recombinant human erythropoietin use among patients on maintenance dialysis has been suggested to play a pivotal role. However, the impact of therapy with recombinant erythropoietin on the immune response to HBV vaccine in patients with chronic kidney disease (CKD) is not appropriately detailed.

AIM

To evaluate the influence of human recombinant erythropoietin therapy on the immunological response to HBV vaccine in CKD patients by performing a systematic review of the literature with a meta-analysis of clinical studies.

METHODS

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 titers at completion of a hepatitis B vaccine schedule among human erythropoietin users versus those who did not receive the drug in a CKD population.

RESULTS

We identified 11 studies involving 862 unique patients with CKD. Aggregation of study results did not show a significant increase in response rates among erythropoietin user versus non-user patients (pooled odds ratio = 1.431; 95% CI 0.954; 2.146), according to a random-effects model. No heterogeneity was found, the p value was 0.1 for our test of study heterogeneity (Q = 14.147). Stratified analysis in various subgroups of interest did not significantly change these findings.

CONCLUSIONS

Our meta-analysis showed no link between immunological response to HBV vaccine and therapy with human recombinant erythropoietin among individuals on long-term dialysis. We suggest the use of recombinant vaccine towards hepatitis B in patients on regular dialysis irrespective of erythropoietin treatment.

Hepatitis B virus vaccine in chronic kidney disease: improved immunogenicity by adjuvants? A meta-analysis of randomized trials

BACKGROUND

Patients with chronic kidney disease typically show an impaired immune response to hepatitis B virus vaccine compared with healthy individuals. A variety of inherited or acquired factors have been implicated in this diminished response. Some authors suggested a benefit with adjuvantation to improve the immunogenicity of existing HBV vaccines.

AIM

To evaluate the efficacy and safety of adjuvantation for hepatitis B virus vaccine in patients with chronic kidney disease.

METHODS

Only prospective, randomized clinical trials (RCTs) were included. We used the random effects model of DerSimonian and Laird with heterogeneity and subgroups analyses. The primary end-point of interest was the seroprotection rate after HBV vaccination with recombinant vaccine plus adjuvants (study group) versus recombinant vaccine alone (control group).

RESULTS

We identified ten studies involving 1228 unique patients with chronic kidney disease. Pooling of study results did not show a significant increase in seroprotection rate among study (HBV recombinant vaccine plus adjuvants) versus control (HBV recombinant alone) patients; the pooled odds ratio of seroprotection rate was 1.47 (95% CI: 0.88; 2.46, NS). The pooled OR for seroresponse rate after HBV vaccine (adjuvanted recombinant vaccine versus recombinant vaccine alone) did not change in the subgroup of studies based on novel adjuvant systems (i.e., HBV-AS04 or HBV-AS02), the pooled OR was 2.22 (95% CI, 0.72; 6.78), NS. Q-test for heterogeneity being 10.819 (P=0.004).

CONCLUSIONS

Our meta-analysis showed that adjuvanted hepatitis B vaccine did not significantly improve the seroprotection rate in patients with renal insufficiency. These results do not support adjuvantation as an approach to increase the immunogenicity of existing recombinant vaccines towards HBV in this high-risk population.

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.

Meta-analysis: the impact of diabetes mellitus on the immunological response to hepatitis B virus vaccine in dialysis patients

BACKGROUND

Patients on maintenance dialysis typically show a suboptimal immune response to hepatitis B virus vaccine compared with the non-uraemic population. A variety of inherited or acquired factors have been implicated in this diminished response. It is well known that patients with diabetes mellitus have a compromised immune system, and diabetic nephropathy is an important cause of chronic kidney disease. However, the impact of diabetes mellitus on the immune response to HBV vaccine in patients receiving long-term dialysis remains unclear.

AIM

To evaluate the influence of diabetes mellitus on the immune response to HBV vaccine in dialysis population by performing a systematic review of the literature with a meta-analysis of clinical studies.

METHODS

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 antibody against hepatitis B surface antigen at completion of vaccine schedule in the diabetic vs. the nondiabetic dialysis individuals.

RESULTS

We identified 12 studies involving 1002 unique patients on long-term dialysis. Aggregation of study results showed a significant decrease in response rates among the diabetic vs. the nondiabetic patients [pooled odds ratio=0.52 (95% CI 0.38-0.71)]. The P-value was 0.29 for our test of study heterogeneity. Stratified analysis in various subgroups of interest did not meaningfully change our results.

CONCLUSIONS

Our meta-analysis showed a clear association between diabetes mellitus and impaired response to hepatitis B virus vaccine in individuals on long-term dialysis. Such a relationship is biologically plausible. Vaccination schedules with adapted vaccine doses and frequent serum testing for loss of immunity against hepatitis B virus should be considered in patients on maintenance dialysis with diabetes mellitus.

Intradermal versus intramuscular hepatitis B vaccination in hemodialysis patients: a prospective open-label randomized controlled trial in nonresponders to primary vaccination

BACKGROUND

Primary hepatitis B virus (HBV) vaccination through the intramuscular (IM) route is less efficacious in dialysis patients than in the general population. Previous studies suggest improved seroconversion with intradermal (ID) vaccination.

STUDY DESIGN

Prospective open-label randomized controlled trial.

SETTING & PARTICIPANTS

Hemodialysis patients nonresponsive to primary HBV vaccination.

INTERVENTION

Revaccination with either ID (10 microg of vaccine every week for 8 weeks) [DOSAGE ERROR CORRECTED] or IM (40 microg of vaccine at weeks 1 and 8) HBV vaccine .

OUTCOMES

PRIMARY OUTCOME

proportion of patients achieving HBV surface antibody (anti-HBs) titer of 10 IU/L or greater within 2 months of vaccination course.

SECONDARY OUTCOMES

time to seroconversion, predictors of seroconversion, peak antibody titer, duration of seroprotection, and safety and tolerability of vaccine.

MEASUREMENTS

Anti-HBs titer to 24 months.

RESULTS

59 patients were analyzed. Seroconversion rates were 79% ID versus 40% IM (P = 0.002). The unadjusted odds ratio for seroconversion for ID versus IM was 5.5 (95% confidence interval [CI], 1.6 to 18.4) and increased with adjustment for baseline differences. The only factor predictive of seroconversion was the ID vaccination route. The geometric mean peak antibody titer was significantly greater in the ID versus IM group: 239 IU/L (95% CI, 131 to 434) versus 78 IU/L (95% CI, 36 to 168; P < 0.001). There was a trend toward longer duration of seroprotection with ID vaccination. ID vaccine was safe and well tolerated.

LIMITATIONS

Inability to distinguish whether the mechanism of the greater efficacy of ID vaccination was the cumulative effect of multiple injections or route of administration; use of anti-HBs as a surrogate marker of protection; lack of evidence of long-term protection.

CONCLUSIONS

Significantly greater seroconversion rates and peak antibody titers can be achieved with ID compared with IM vaccination in hemodialysis patients nonresponsive to primary vaccination. ID vaccination should become the standard of care in this setting.

Safety and immunogenicity of a new hepatitis B vaccine for the protection of patients with renal insufficiency including pre-haemodialysis and haemodialysis patients

BACKGROUND

High susceptibility to infections including the hepatitis B virus (HBV) causes increased morbidity and mortality in patients with end stage renal disease. HBV vaccination is recommended for all patients undergoing dialysis; however, antibody response is much lower than in healthy individuals.

OBJECTIVE

This review discusses the clinical experience with HBV vaccine with a novel adjuvant system among dialysed patients.

METHOD

A new adjuvanted HBV vaccine (Fendrix(), GlaxoSmithKline Biologicals, Rixensart, Belgium) contains as active substance 20 microg recombinant hepatitis B surface antigen produced in Saccharomyces cerevisiae and the novel adjuvant system composed of aluminum salt and 3-O-desacyl-4'-monophosphoryl lipid A (AS04).

CONCLUSION

HBV-AS04 vaccine has a good safety profile with clinically acceptable reactions similar to standard HBV vaccines and has elicited earlier antibody response and higher antibody titres in pre and haemodialysis patients as compared with four double doses of standard HBV vaccine.

Overview of vaccination in chronic kidney disease

Infections are a major cause of death in end-stage renal disease (ESRD) patients, second only to cardiovascular disease, and also contribute to significant morbidity in patients with earlier stages of chronic kidney disease (CKD). Vaccines are a strategy to attempt to reduce morbidity related to infections. Patients with CKD and ESRD may not respond as well to vaccines as patients without kidney failure, but adequate seroresponse with standard or augmented regimens for vaccinations against influenza, hepatitis B, pneumococcus, and varicella have been documented. Influenza, in particular, seems to provide adequate protection with standard dosing regimens. Despite somewhat reduced effectiveness of certain vaccines in patients with CKD, there is emerging evidence of benefit to vaccination in these populations. However, vaccination rates are relatively low. Given the accumulating evidence of benefit, continuing quality improvement programs focused on increasing vaccination rates in patients with all levels of CKD are needed.

A comparison of responsiveness to hepatitis B vaccination in patients on hemodialysis and peritoneal dialysis

The doses of hepatitis B vaccine given to peritoneal dialysis (PD) patients are currently based on responsiveness data from hemodialysis (HD) patients. To determine whether the doses are also appropriate from PD patients, we did a head-to-head comparison of short-term and 2-year responses to hepatitis B vaccination of HD patients and PD patients. We evaluated serum titers of the antibody to hepatitis B surface antigen (anti-HBs) after the patients had completed a course of four consecutive intramuscular vaccinations (40 microg of Engerix-B administered into the deltoid muscle at 0, 1, 2, and 6 months) in 69 dialysis patients (47 HD and 22 PD patients) who were both hepatitis B surface antigen (HBsAg) and anti-HBs negative. No patients had received a hepatitis B vaccination prior to the study. There was no significant difference in response to hepatitis B vaccination between the HD and PD groups (78.7% versus 77.3%, p=0.33). The seroconversion rate defined as anti-HBs > or = 10IU/L was influenced only by age (p=0.011). There was also no significant difference in responsiveness between the HD and PD groups (60% versus 50%, p=0.41) at a 2-year follow-up. We conclude that doses of HBV vaccine being used for HD patients are also appropriate for PD patients and a booster dose of vaccine is required to maintain seroprotection for those who lost protecting anti-HBs.

Stage of chronic kidney disease predicts seroconversion after hepatitis B immunization: earlier is better

BACKGROUND

Hepatitis B virus (HBV) infection remains a concern in dialysis populations, and vaccination programs have been less successful than those in the general population. Reasons for poor response include malnutrition, uremia, and the generalized immunosuppressive state of patients with chronic kidney disease (CKD). This prospective cohort study evaluated factors impacting on the effectiveness of a vaccination program before dialysis therapy initiation, including level of kidney function.

METHODS

All patients receiving care in the Kidney Function Clinic (St Paul's Hospital, Vancouver, Canada) were screened for previous HBV infection or vaccination. Those who were marker negative were administered a standardized hepatitis B vaccination schedule recommended for patients with CKD. The primary outcome measure, seroconversion, is defined as hepatitis B surface antibody titer greater than 10 IU 3 months after completion of the vaccination schedule.

RESULTS

The study population of 165 patients included 64% men with a mean age of 60 years, mean serum creatinine level of 3.4 +/- 1.5 mg/dL (300 +/- 133 micromol/L), and median estimated glomerular filtration rate (GFR) of 20 mL/min (interquartile range, 14 to 20). Seroconversion rate was 82%. Multivariate analyses showed the independent predictive value of level of GFR. The model showed that patients with the lowest level of kidney function and who were older and had diabetes were less likely to seroconvert (P < 0.05).

CONCLUSION

This is the largest study to show in a well-characterized cohort that patients with higher GFR levels are more likely to respond to hepatitis B vaccination programs with seroconversion, independent of other factors. Future studies will explore specific mechanisms to explain this phenomenon.

The Value of Vaccination in Chronic Kidney Disease

There has been much attention directed toward the high mortality of patients with end-stage renal disease (ESRD), with much of the focus on cardiovascular disease. However, infectious disease is the second most common cause of death in late-stage chronic kidney disease (CKD) patients. Although CKD patients are immunocompromised, some vaccines such as influenza, retain their efficacy and reduce infection rates with a standard immunization schedule. Other vaccines, such as hepatitis B and pneumococcal vaccines, require more frequent and/or higher doses to produce and maintain protective antibody levels. Attention has recently been given to the efficacy of influenza vaccination in ESRD patients in reducing morbidity and mortality. Centers with vaccination protocols have demonstrated reduced infection rates and resultant decreased morbidity and mortality. It could be extrapolated from this that widespread vaccination would reduce the total cost of ESRD patient care, and potentially improve patient well-being. However, vaccination appears to be underutilized in CKD patients, and it is a readily available intervention to improve outcomes.

Immunologic defects and vaccination in patients with chronic renal failure

Patients with chronic renal failure suffer from defective host defenses which are directly the result of the renal impairment, in addition to those dependent on the primary illness leading to the renal failure. The mechanisms underlying the defective responses in phagocytic cells, lymphocytes and antigen processing are likely due to either failure to adequately eliminate suppressive compounds by the defective kidneys or to improper metabolic processing of the factors by the damaged renal parynchema. That some of the defects are reversed by transplantation and not dialysis suggests that renal parenchymal metabolic activities may be involved, although it is also possible that functioning glomerular cells are capable of filtering substances that membranes are not currently capable of eliminating. The current strategy for dealing with the immunodeficiency appears to be totally based on developing means to circumvent the defective function. The other approach, correction of the impaired function, cannot be even considered until the mechanisms underlying the defective function of the cells involved in defenses are better delineated. It seems possible that one or a few compounds are pivotal in altering the function of all the affected cell lines, since, with only a small amount of effort, it is possible to relate the dysfunction to abnormal cell membrane functions in phagocytic cells, dendritic cells and lymphocytes. Until the biochemical basis of the dysfunction of all the cell types affected are better defined, such exercises cannot be translated into better management of patients with chronic renal failure. Proper function of host defenses requires that appropriate cells can properly respond to threats to host viability. For the cells of the immune system (phagocytes and lymphocytes) this means that their response to regulatory molecules be appropriate, that their mobility be normal, that their adherence to substrates be preserved, and that they can generate the appropriate response to the challenge. For neutrophils, for example, it is necessary that they recognize and mobilize appropriately to chemotactic stimuli, that they be able to adhere to and migrate through endothelial lining, that their phagocytic activity be sufficient, and that they can kill and degrade endocytosed particles and generate appropriate secretions. Similar lists of requirements for good function can be generated for any cell type in the immune defense system. Uremia, as well as currently available treatments for uremia, directly or indirectly alters the function of all phases of appropriate immune cell function. Defective host responses in uremia have been recognized for decades and there has been considerable effort in the past decade to better define the extent and mechanisms of impaired defenses. Despite the multitude of major defects in humoral, cellular, and inflammatory processes, uremic patients who are cared for today, although they remain at higher risk of serious infectious complications, can and do maintain a good quality of life, with most remaining free of major infections for years and decades.

Over a decade of experience with a yeast recombinant hepatitis B vaccine

Experience with the yeast recombinant hepatitis B vaccine Engerix-B now exceeds 10 years. We reviewed published studies on this vaccine. These show the vaccine to be safe, causing mostly only minor local symptoms and to be highly immunogenic both in monitored clinical trials and under field conditions. Engerix-B consistently elicits high geometric mean antibody titres and a high protective efficacy has been established in three groups at high-risk of hepatitis B infection, homosexual men, institutionalised mentally handicapped subjects and neonates of chronic carrier mothers. The profile of the recombinant hepatitis B vaccine in certain high-risk groups and immuno compromised people is discussed. Finally we present updated post marketing surveillance data based on 496 million distributed doses of vaccine.

Immunogenicity of hepatitis A vaccine in decompensated liver disease

OBJECTIVE

Hepatitis A can cause decompensation and death in patients with previous liver injury. The hepatitis A vaccine is recommended for patients with chronic liver disease. The aim of this study was to screen, immunize, and measure the safety and antibody response of the hepatitis A vaccine in liver failure and liver transplant patients.

METHODS

This was a prospective immunization trial at a referral center for liver disease and liver transplantation. A total of 193 patients with severe chronic liver disease were screened and 24 patients were vaccinated. Sixteen end stage liver disease patients were compared with eight liver transplant patients. Hepatitis A vaccinations using 1440 ELISA units were given at 0 and 2 months. Serum hepatitis A antibody titers were measured after each vaccine dose. An antibody response > or = 33 mIU/ml was considered protective.

RESULTS

Screening seropositive rate was 70 of 193 (36%) and 24 patients were available for vaccination. The median antibody titer was markedly lower in liver transplant patients, 0.0 mIU/ml compared to liver failure patients 34.7 mIU/ml (p < 0.001). Liver transplant recipients did not respond to the vaccine (0 of eight patients) compared with seven of 14 liver failure patients (seroconversion rate 50%, p = 0.02).

CONCLUSIONS

Liver failure significantly reduces the antibody response to hepatitis A vaccine, and liver transplant recipients were unable to respond to the vaccine. Although this study was small, immunization should be considered early for susceptible patients with chronic liver disease because the development of liver failure may blunt the immunogenicity of the vaccine.

Prospective analysis of the factors influencing the antibody response to hepatitis B vaccine in hemodialysis patients

Hepatitis B vaccine is effective in producing protection against hepatitis B virus (HBV) infection in hemodialysis (HD) patients, but the antibody response is variable. To identify those factors implicated in the vaccine response, in a prospective study over a 24-month period, we vaccinated 80 seronegative patients on HD (group A) and monitored clinical, biochemical, and immunologic parameters. The protective immunity acquired by vaccination was compared with that developed through HBV infection in 22 age-matched HD patients (group B). The anti-HBs antibody-seronegative patients followed a four-dose vaccination schedule (0, 1, 2, and 6 months) with 40 microg DNA-recombinant hepatitis B vaccine. One month after vaccination, 77.5% of the patients had seroconverted, and 72.5% achieved high antibody response, whereas 22.5% were nonresponders. Patients aged younger than 40 years seroconverted 100%; those aged 40 to 60 years, 75% (P < 0.01); and patients older than 60 years, 74% (P < 0.001). No differences between responders and nonresponders concerning sex, time on HD, HD dose, nutritional status, hemoglobin level, HD membrane, iPTH level, calcitriol treatment, or number of transfusions during vaccination were found. The presence of other factors, such as recombinant human erythropoietin (rHuEPO) therapy or hepatitis C virus (HCV) infection, did not significantly influence antibody responses to hepatitis B immunization. A greater frequency of DR3 (53.8% v 25.7%, P < 0.05), DR7 (53.8% v 18.6%, P < 0.01), and DQ2 (76.9% v 44.1%, P < 0.05), and a lesser frequency of A2 (7.7% v 37.2%, P < 0.05) were found in nonresponders compared with responders. Eighteen months after vaccination, the analysis showed similar antibody titers but lower seroconversion rates in group A as compared with group B. In conclusion, unresponsiveness to hepatitis B vaccine in HD patients was related to factors such as older age, the presence of DR3, DR7, and DQ2, and the absence of A2 alleles. Although the seroprotection produced by the vaccine was less than that achieved through natural HBV infection, our protocol of vaccination was sufficiently immunogenic and provided lasting protection.