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ORIGINAL ARTICLE
Year : 2017  |  Volume : 30  |  Issue : 1  |  Page : 184-189

Assessment of immune response to hepatitis B virus vaccine in chronic hemodialysis patients


1 Department of Tropical Medicine, Faculty of Medicine, Menoufia University, Al Minufya, Egypt
2 Department of Medical Biochemistry, Faculty of Medicine, Menoufia University, Al Minufya, Egypt

Date of Submission08-Nov-2016
Date of Acceptance21-Dec-2016
Date of Web Publication25-Jul-2017

Correspondence Address:
Shaymaa F Mohamed
Department of Tropical Medicine, Faculty of Medicine, Menoufia University, Sers El-Lian, Al Minufya, Menoufia, 32861
Egypt
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/1110-2098.211523

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  Abstract 


Objective
This study aimed to assess the immune response to hepatitis B virus (HBV) vaccine in chronic hemodialysis (HD) patients.
Background
HBV is an important public health problem in humans. Currently available HB vaccines have an excellent safety and immunogenicity profile. Anti-HBs are the only easily measurable correlate of vaccine-induced protection. Dialyzed patients have impaired immune response and lower seroconversion rates compared with the general population.
Patients and methods
This study was conducted on 50 patients with chronic renal failure on hemodialysis (HD) and 30 healthy persons. These patients were subjected to full history taking, complete clinical examination, complete blood picture, liver function tests, renal function tests, serum Na, K, and Ca, abdominal and pelvic ultrasound, HBsAg, anti-HBs, anti-HBc, and HCV-Ab by ELISA.
Results
There was a highly significant decrease in the mean value of anti-HBs titer in the HD group when compared with the control group. In addition, there was a highly significant decrease in the mean value of inadequate anti-HBs titer and a significant decrease in the mean value of adequate anti-HBs titer in the HD group when compared with the control group. A significant negative correlation between anti-HBs titer and age was found. There was a highly significant negative correlation between anti-HBs titer and serum creatinine levels and blood urea. A significant positive correlation between anti-HBs titer and serum albumin levels was found.
Conclusion
Response of HD patients to HB vaccine is inadequate, with significant negative correlation with serum creatinine, blood urea levels, and age, and a significant positive correlation with serum albumin.

Keywords: hepatitis B virus, hemodialysis patients, vaccination


How to cite this article:
Mohammed HI, El-Hefenawy SM, Mohamed SF. Assessment of immune response to hepatitis B virus vaccine in chronic hemodialysis patients. Menoufia Med J 2017;30:184-9

How to cite this URL:
Mohammed HI, El-Hefenawy SM, Mohamed SF. Assessment of immune response to hepatitis B virus vaccine in chronic hemodialysis patients. Menoufia Med J [serial online] 2017 [cited 2019 Apr 21];30:184-9. Available from: http://www.mmj.eg.net/text.asp?2017/30/1/184/211523




  Introduction Top


Hepatitis B virus (HBV) is a common cause of liver disease throughout the world. An estimated one-third of the world's population had serologic evidence of past infection, and the virus causes more than one million deaths annually [1]. Transmission of hepatitis B virus results from exposure to infectious blood or body fluids [2]. Special population groups, among them patients with chronic kidney disease requiring renal replacement therapy, essentially hemodialysis (HD), are already recognized as a risk group because of repeated, prolonged exposure of blood in the extracorporeal circuit. Furthermore, patients with end-stage renal disease, whether predialysis or chronic dialysis, are immunodeficient, rendering them at an increased susceptibility to infection and subsequent disease [3].

Hepatitis B (HB) may be largely preventable by vaccination. Administration of hepatitis B recombinant vaccines leads to the development of protective antibodies to HBV (anti-HBs) in responders. Lack of the development of anti-HBs means susceptibility to HBV infection. Strict infection control procedures during HD sessions, as well as hepatitis B vaccination, are introduced on a mandatory basis in most HD centers worldwide [4]. An antibody level between 10 and 100 IU/ml is considered as a poor response, and these people should receive a single booster vaccination at this time [5].

A time-related anti-HBs decline is a well-known phenomenon. In the general population, hepatitis B vaccination provided strong protection against infection. In dialyzed patients, loss of anti-HBs is more rapid than in the general population [4]. It is important to determine the median duration of hepatitis B immunity and to study the effect of vaccination timing in dialysis patients [6].

The present study aimed to assess immune response (level of anti-HBs titer) to HB vaccine after 6 months of completing the course of the vaccine (at the end of first year of the beginning of vaccine).


  Patients and Methods Top


This study was conducted on 50 patients with chronic HD, selected from attendance to the dialysis unit of Menouf fever hospital, Menoufia governorate, during the period from May 2014 to May 2015, versus 30 healthy persons matched for age and sex. Ethical approval was taken for conducting this study. Patients and controls were classified into the following groups:

Group I (hemodialysis) group

This group included 50 patients with chronic renal failure on HD. There were 24 (48%) male and 26 (52%) female patients. Their ages ranged between 35 and 59 years, with a mean value of 48.54 ± 5.91 years. Etiology of CRF was primary renal diseases (21 patients), diabetes mellitus (20 patients), and systemic hypertension (nine patients).

Group II (control group)

This group included 30 healthy persons. There were 13 (43.3%) male and 17 (56.7%) female patients. Their ages ranged between 35 and 58 years, with a mean value of 47.27 ± 6.88 years [Figure 1],[Figure 2],[Figure 3],[Figure 4].
Figure 1: Significant negative correlation between anti-HBs titer and age. (r: −0.61 and P: <0.001).

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Figure 2: Highly significant negative correlation between anti-HBs titer and serum creatinine levels. (r: −0.82 and P: <0.001).

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Figure 3: Highly significant negative correlation between anti-HBs titer and blood urea. (r: −0.61 and P: <0.001).

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Figure 4: Significant positive correlation between anti-HBs titer and serum albumin levels. (r: −0.33 and P: 0.02).

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Inclusion criteria

All studied groups were negative for HCV-Ab and for all serologic markers of HBV before starting the study, and did not receive HB vaccine in the past. They were subjected to HB vaccination [the second-generation recombinant DNA-HB vaccine (Energix HB)) at a dose of 1.0 ml (20 μg HBsAg) for control group and 2.0 ml (40 μg HBsAg) for the HD group administered at 0, 1, and 6 months by intramuscular (deltoid) injection (according to infection control program in Menouf fever hospital).

All patients and control groups were subjected to the following:

  1. Thorough history taking and full clinical examination
  2. Laboratory investigations:

    1. Complete blood count
    2. Liver function tests, including serum alanine transaminase, aspartate transaminase, and serum albumin
    3. Renal functions, including blood urea and serum creatinine, Na, K, and Ca


  3. Imaging study: Ultrasonography of the abdomen and pelvis was performed to assess size and echopattern of the liver, spleen, and kidney and to assess any venous thrombosis, presence or absence of ascites, any masses, or lymph nodes
  4. Serological study:

    1. HBsAg using ELISA
    2. Measurement of anti-HBs titer by ELISA
    3. Detection of antibodies to hepatitis B core antigen (anti-HBc) by (ELISA)
    4. Detection of HCV-Ab by (ELISA).


Collection

The blood samples were taken under complete aseptic conditions and before any drug medications. Blood was collected by vein puncture, was allowed to coagulate at room temperature for 10–20 min, it was centrifuged for 20 min at a speed of 2000–3000 rpm, and then the supernatant was removed. Hemolytic or contaminated serum was not used. The specimens were stored frozen at 20°C until testing.

Storage

Specimens were capped and were frozen at −20°C before assay.

Estimation of anti-HBs titer in serum

Anti-HBs titer was estimated in the serum sample using the ELISA kit (Roche Diagnostics, Indianapolis, IN, USA). The test principle was based on the 'sandwich principle'. The solid phase of the microtiter plate is made up of polystyrene wells coated with HBsAg (subtype Ad and Ay) and the liquid phase of peroxidase-conjugated HBsAg (subtype Ad and Ay). When a serum or plasma specimen containing anti-HBs is added to the HBsAg-coated wells together with the peroxidase-conjugated HBsAg and incubated, antigen–anti-HBs–antigen–peroxidase complexes will form on the wells. After washing the microtiter plate to remove unbound material, a solution of tetramethylbenzidine substrate is added to the wells and incubated. A blue color develops in proportion to the amount of anti-HBs bound to HBsAg. The peroxidase–tetramethylbenzidine reaction is stopped by the addition of sulfuric acid. The optical density of developed color is read with a suitable photometer at 450 nm with a selected reference wavelength within 620–690 nm.

Statistical analysis

The data collected were tabulated and analyzed by SPSS (statistical package for social science), version 17.0 on IBM compatible computer (SPSS Inc., Chicago, Illinois, USA), and for all analyses a P value less than 0.05 was considered significant.


  Results Top


Statistical analysis revealed no significant difference between the studied group as regards age (t = 0.87, P = 0.38) and sex distribution (χ2 = 0.16, P = 0.68).

There was a highly significant increase in the number of patients on HD with inadequate immune response to HB vaccine (anti-HBs Ab = 10–100 iu/l) when compared with the control group [32 out of 50 (64%) vs. eight out 30 (26.7%)), whereas the number of controls with adequate immune response (anti-HBs titer >100 IU/l) was highly significant when compared with the HD group [22 out of 30 (73.3%) vs. 18 out of 50 (36%)). None of the studied group members had anti-HBs titer of less than 10 IU/l [Table 1].
Table 1 HB vaccine immune response (anti.HBs titer) among studied groups

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There was a highly significant decrease in the mean value of anti-HBs titer in the HD group (81.84 ± 48.39 IU/l) when compared with the control group (125.37 ± 39.96 IU/l). In addition, there was a highly significant decrease in the mean value of inadequate anti-HBs titer (52.13 ± 28.27 IU/l) and a significant decrease in the mean value of adequate anti-HBs titer (134.67 ± 16.00 IU/l) in the HD group when compared with the control group (80.37 ± 18.96 IU/l, 146.22 ± 19.19 IU/l), respectively [Table 2].
Table 2 Mean values of anti-HBs titer among studied groups

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There was a nonsignificant difference between diabetic and nondiabetic HD subgroups as regards the number of patients with HB vaccine immune response (χ2 = 10.47 and P = 0.27). Response to HB vaccine was inadequate in 13 out of 20 diabetic HD patients versus 19 out of 30 nondiabetic HD patients, whereas the response was adequate in seven out of 20 diabetic HD patients versus 11 out of 30 nondiabetic HD patients [Table 3].
Table 3 Effect of diabetes on hepatitis B vaccine immune response in hemodialysis group in comparison with the control group

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There was a highly significant increase in the mean value of anti-HBs titer (P = 0.0009) [in control group (125.37 ± 39.96) when compared with the diabetic HD subgroup (73.25 ± 48.51), whereas this increase was significant when compared with the nondiabetic HD subgroup (87.57 ± 48.27)). However, there was no significant difference between diabetic and nondiabetic HD subgroups as regards mean values of serum anti-HBs titer (P = 0.27) [Table 4].
Table 4 Mean values of anti-HBs titer in studied groups in relation to diabetes

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  Discussion Top


The present study revealed 100% seroconversion to HB vaccine in both groups (anti-HBs >10 IU/l), whereas the difference between both groups was in the adequacy of this immune response (level of anti-HBs). There was a highly significant increase in the number of patients on HD with inadequate immune response to HB vaccine (anti-HBs Ab between 10 and 100 IU/l) when compared with the control group [32 out of 50 (64%) vs. eight out 30 (26.7%)), whereas the number of controls with adequate immune response (anti-HBs titer >100 IU/l) was highly significant when compared with the HD group [22 out of 30 (73.3%) vs. 18 out of 50 (36%)). HB vaccine immune response in HD patients was studied in many studies with various reports. Buti et al. [7] followed up 60 HD patients up to 3 years after primary hepatitis B vaccination series (four doses of Engerix B, 20 mg/dose) to evaluate the level of anti-HBs titer and its persistence. The authors reported that HD patients not only had lower response rates to HB (73% of patients were responders with anti-HBs levels ≥10 IU/l versus 27% nonresponders even with further booster dose, anti-HBs persistently <10 IU/l) but also that these are frequently transient (41% of responders had no detectable anti-HBs levels after 3 years of follow-up). Chin [8] retrospectively examined new HD patients who received HBV recombinant vaccine and were HBsAg-negative, anti-HBs-negative, and anti-HCV-negative at the start of HD to evaluate HB vaccine immune response in these patients. The author reported that 33 out of 97 (34.02%) patients were nonresponders and 64 out of 97 (65.98%) patients were responders. Fabrizi et al. [9] in a meta-analysis of randomized trials evaluated the efficacy and safety of adjuvantation for HBV vaccine in patients with chronic kidney disease. The authors concluded that adjuvanted HBV vaccine did not significantly improve the seroprotection rate in patients with renal insufficiency and they did not support adjuvantation as an approach to increase the immunogenicity of existing recombinant vaccines toward HBV in this high-risk population. Al Saran et al. [10], in their study aimed to determine the response to HBV vaccination in patients on HD and to identify the factors that could affect this response, reported that 129 out of 144 (89.64%) patients were responders (anti-HBs ≥ 10), whereas nonresponders (anti-HBs < 10 IU/l) were 15 out of 144 (10.4%) patients. Ayub et al. [11] followed up 83 HD patients and collected quantitative serologic measurements every 2 months over a 1-year period to determine HB vaccine immune response in these patients. The authors reported that 1 month after the vaccination period 41, 21.7, and 37.3% of the patients were nonresponders (anti-HBs <10 IU/l), poor responders (anti-HBs between 10 and 100 IU/l), and good responders (anti-HBs >100 IU/l), respectively, and all patients displayed decreasing antibody titers during the observation period. Moreover, anti-HBs titer in good responders dropped to unprotected level in 8 and 32% after one and 2 years in these patients, respectively.

There was a highly significant decrease in the mean value of anti-HBs titer in the HD group (81.84 ± 48.39 IU/l) when compared with the control group (125.37 ± 39.96 IU/l). In addition, there was a highly significant decrease in the mean value of inadequate anti-HBs titer (52.13 ± 28.27 IU/l) and a significant decrease in the mean value of adequate anti-HBs titer (134.67 ± 16.00 IU/l) in the HD group when compared with the control group (146.22 ± 19.19 IU/l). The decreased mean anti-HBs values (adequate and inadequate) in HD patients in the present study agreed with the results of Baradana et al. [12], who studied serum anti-Hbs-Ag in stable HD patients and its relationship with various demographic and biochemical data. The authors reported a highly significant decrease in the mean value of anti-HBs in HD patients (35 ± 55 IU/l) when compared with that of healthy control (135 ± 71 IU/l).

The present study revealed a nonsignificant difference between diabetic and nondiabetic HD subgroup as regards HB vaccine immune response values (adequate and inadequate). These results agreed with some of the previous studies and disagreed with others. Al Saran et al. [10] in their study aimed to determine factors affecting the response to HB vaccine among HD patients and used HbA1c as an indicator for glycemic control in diabetic patients. The authors reported no statistically significant difference between responder and nonresponder groups and diabetes mellitus. However, Chin et al. [8], in their study to determine studied baseline characteristics that affect HB vaccine immune response in HD patients, reported that the presence of DM at the time of HD initiation was a significant independent factor associated with HB vaccine nonresponse. In addition, Schillie et al. [13] reported that young adults with diabetes generally have responses similar to persons of comparable age without diabetes. However, older adults have a reduced response, and older adults with diabetes seem to have further impairment in vaccine response, particularly those with coexisting kidney conditions. There are several hypotheses about the biological basis for potentially impaired cellular immune response to vaccination among persons with diabetes, including a reduction in the number of circulating helper T cells, the CD4-to-CD8 lymphocyte ratio, and lymphocyte blastogenesis [14] and defects with antigen presentation [15]. Impaired vaccine response also has been linked to the presence of DR3, DR7, and DQ2 human leukocyte antigen alleles among persons with diabetes [16].

The present study revealed significant negative correlation between anti-HBs titer and age in the HD subgroup. Many previous studies agreed with our result and support that age is a very well-established negative factor of HB vaccination failure in HD patients. Shatat et al. [17] reported that seroconversion rate to HB vaccine was 84% in HD patients below age 40 years and only 33% in those with age of 60 years or older. Similarly, Jadoul and Gouber [18] in their study aimed to assess the success of HB vaccine immune response in elderly HD patients and reported that seroconversion rates after 12 months were 100, 75, and 50% in patients aged below 60, 60–75, and above 75 years, respectively. The authors concluded that the ultimate decision to vaccinate elderly HD patients should depend on the local epidemiology of HBV infection and the individual risk of acquiring HBV. In addition, Fabrizi et al. [19] reported a significant nonresponse to HB vaccine among older dialysis patients, and an additional dose of vaccine did not appear to have an impact in response rate by age. In contrast, our results disagreed with the result of Khashaba et al. [20], who reported that age at the onset of HD did not affect immune response to HB vaccine.

The present study revealed a highly significant negative correlation between anti-HBs titer and serum creatinine (r: −0.82, P: <0.001) and blood urea levels (r: −0.61, P: <0.001) in the HD subgroup. This result agreed with those of Daroza et al. [21] and Ghadiani et al. [22], who reported that in the latest stage of kidney disease HB vaccination is less likely to induce seroconversion compared with the earlier stage. However, Hashemi et al. [23] detected no significant correlation between anti-HBs titer and serum creatinine and blood urea levels. In addition, Al Saran et al. [10] showed a nonstatistically significant difference between the responders and nonresponders regarding dialysis adequacy, which was evaluated by urea reduction ratio.

The present study revealed a significant positive correlation between anti-HBs titer and serum albumin levels in the HD subgroup (r: 0.33, P = 0.02). These results were in agreement with those of Brown et al. [24], in their prospective study of HB vaccine (a comparison of responders vs. non responders), who reported that serum albumin level as a nutritional marker was the only variable overall to show significance in achieving seroconversion and that patients with hypoalbuminemia are unable to produce adequate titers of anti-HBs. In contrast, Baradana et al. [12] and Al Saran et al. [10] reported that there was no significant difference between responders and nonresponders to HB vaccine as regards serum albumin levels (P = 0.27).


  Conclusion Top


HB vaccine immune response in CRF patients on HD was adequate (anti-HBstiter >100 IU/l) only in 36% of patients versus 73.3% of control, whereas it was inadequate (anti-HBs titer ≤100 IU/l) in 64% of patients versus 26.7% of control. This immune response (anti-HBs) could be correlated positively with serum albumin level and negatively with age, serum creatinine, and blood urea levels.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
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