Immune response to hepatitis B vaccination in pediatric patients with inflammatory bowel disease

Overview of Hepatitis B Vaccine Non-Response and Associated B Cell Amnesia: A Scoping Review

BACKGROUND

The advent of the hepatitis B vaccine has achieved tremendous success in eradicating and reducing the burden of hepatitis B infection, which is the main culprit for hepatocellular carcinoma-one of the most fatal malignancies globally. Response to the vaccine is achieved in about 90-95% of healthy individuals and up to only 50% in immunocompromised patients. This review aimed to provide an overview of hepatitis B vaccine non-response, the mechanisms involved, B cell amnesia, and strategies to overcome it.

METHODS

Databases, including Google Scholar, PubMed, Scopus, Cochrane, and ClinicalTrials.org, were used to search and retrieve articles using keywords on hepatitis B vaccine non-response and B cell amnesia. The PRISMA guideline was followed in identifying studies, screening, selection, and reporting of findings.

RESULTS

A total of 133 studies on hepatitis B vaccine non-response, mechanisms, and prevention/management strategies were included in the review after screening and final selection. Factors responsible for hepatitis B vaccine non-response were found to include genetic, immunological factors, and B cell amnesia in healthy individuals. The genetic factors were sex, HLA haplotypes, and genetic polymorphisms in immune response markers (cytokines). Non-response was common in conditions of immunodeficiency, such as renal failure, haemodialysis, celiac disease, inflammatory bowel disease, hepatitis C co-infection, and latent hepatitis B infection. Others included diabetes mellitus and HIV infection. The mechanisms involved were impaired immune response by suppression of response (T helper cells) or induced suppression of response (through regulatory B and T cells).

DISCUSSION

A comprehensive and careful understanding of the patient factors and the nature of the vaccine contributes to developing effective preventive measures. These include revaccination or booster dose, vaccine administration through the intradermal route, and the use of adjuvants in the vaccine.

Meta-analysis: hepatitis B vaccination in inflammatory bowel disease

BACKGROUND

The response rate of hepatitis B virus (HBV) vaccination in patients with inflammatory bowel disease (IBD) is variable. Increasing dose or accelerated schedule is the suggested strategy to improve seroconversion.

AIM

We performed a meta-analysis to determine the pooled response rate of HBV vaccination and to identify the predictors of seroconversion.

METHODS

We searched PubMed, Embase and Cochrane library databases. Studies reporting the response of HBV vaccination in IBD patients were included. Response was recorded as adequate immune response (AIR, >10 IU/L) and Effective immune response (EIR, >100 IU/L). Pooled AIR and EIR rates were calculated for different doses (10-20 μg or 40 μg) and schedules (standard: 0, 1 and 6 months or accelerated: 0, 1 and 2 months). Meta-analysis was performed to identify the predictors of response.

RESULTS

Twenty-one studies including 2602 patients were eligible. Pooled AIR and EIR rates after HBV vaccination were 62% (95% CI, 55-68) and 42% (95% CI, 37-48), respectively. Pooled AIR and EIR rates for standard and double dose were similar. Pooled AIR and EIR rates were also comparable for different schedules of HBV vaccination. Gender, IBD subtype and disease activity did not affect the response rate. Use of immunosuppression [immunomodulators (RR: 0.73, 95% CI, 0.62-0.87) and anti-TNFs (RR: 0.72, 95% CI, 0.60-0.87)] was a predictor of poor immune response compared to no immunosuppressive therapy.

CONCLUSION

Patients with IBD have a poor serological response after HBV vaccination. HBV screening and vaccination should preferably be done before starting the immunosuppressive drugs.

Vaccines in Children with Inflammatory Bowel Disease: Brief Review

Incidence of inflammatory bowel diseases (IBDs), including Crohn's disease (CD) and ulcerative colitis (UC), is increasing worldwide. Children with IBDs have a dysfunctional immune system and they are frequently treated with immunomodulating drugs and biological therapy, which significantly impair immune system functions and lead to an increased risk of infections. Vaccines are essential to prevent at least part of these infections and this explains why strict compliance to the immunization guidelines specifically prepared for IBD patients is strongly recommended. However, several factors might lead to insufficient immunization. In this paper, present knowledge on the use of vaccines in children with IBDs is discussed. Literature review showed that despite a lack of detailed quantification of the risk of infections in children with IBDs, these children might have infections more frequently than age-matched healthy subjects, and at least in some cases, these infections might be even more severe. Fortunately, most of these infections could be prevented when recommended schedules of immunization are carefully followed. Vaccines given to children with IBDs generally have adequate immunogenicity and safety. Attention must be paid to live attenuated vaccines that can be administered only to children without or with mild immune system function impairment. Vaccination of their caregivers is also recommended. Unfortunately, compliance to these recommendations is generally low and multidisciplinary educational programs to improve vaccination coverage must be planned, in order to protect children with IBD from vaccine-preventable diseases.