Henoch-Schönlein purpura and meningococcal B vaccination

[Association between vaccination and the risk of immunoglobulin A vasculitis in children]

OBJECTIVES

To study the effect of vaccination on the short-term risk of immunoglobulin A vasculitis (IgAV) in children.

METHODS

A retrospective analysis was conducted on the general data and the vaccination history within one year prior to onset in children with IgAV hospitalized in the Children's Hospital Affiliated to Zhengzhou University from November 2021 to January 2023. Vaccine exposure rates in the risk period (3 months prior to IgAV onset) and the control period were compared by autocontrol-case crossover analysis, and the odds ratio and 95% confidence interval (95%CI) were calculated. A sensitivity analysis for the one-month and two-month risk periods was conducted.

RESULTS

A total of 193 children with IgAV were included, with a median age of 7.0 years. Among the 193 children, 36 (18.7%) received at least one dose of the vaccine within 1 year prior to IgAV onset, and 14 (7.3%) received at least one dose of the vaccine during the 3-month risk period. Compared to the unvaccinated IgAV group, the vaccinated IgAV group had a significantly younger age of onset (P<0.05). There were no significant differences in the proportions of children with gastrointestinal involvement, renal involvement, and joint involvement between the two groups (P>0.05). The odds ratio for developing IgAV after receiving any type of vaccine within 3 months prior to IgAV onset was 2.08 (95%CI: 0.82-5.27, P>0.05). Further sensitivity analysis for the 1-month and 2-month risk periods demonstrated that the odds ratios for developing IgAV after receiving any type of vaccine were 2.74 (95%CI: 0.72-10.48, P>0.05) and 2.72 (95%CI: 0.95-7.77, P>0.05), respectively.

CONCLUSIONS

Vaccination dose not increase the risk of IgAV, nor does it exacerbate clinical symptoms in children with IgAV.

IgA vasculitis following COVID-19 vaccination

Immunoglobulin A (IgA) vasculitis is generally triggered by infectious causes, but it has also been reported after immunisation with various vaccines. Herein, we report two cases of IgA vasculitis after receiving the first or second dose of the Pfizer-BioNTech BNT16B2b2 mRNA vaccine. Two men, aged 22 and 30 years, developed palpable purpura on the extremities and arthritis. One patient also complained of fever and gastrointestinal symptoms. Laboratory findings revealed mild leucocytosis and slightly elevated C-reactive protein levels, although the platelet count and coagulation profile were within normal levels in both cases. Proteinuria and microhaematuria were seen in one patient. Skin biopsies were performed in both patients and revealed leucocytoclastic vasculitis. The deposits of IgA and C3 were shown in immunofluorescence studies in one patient. Both patients were diagnosed with IgA vasculitis and treated with prednisolone, and their symptoms resolved within 1 week after initiation of treatment. The coronavirus disease 2019 mRNA vaccine could trigger IgA vasculitis; however, a coincidence cannot be ruled out.

Vaccination and Risk of Childhood IgA Vasculitis

BACKGROUND AND OBJECTIVES

Immunoglobulin A vasculitis (IgAV) might develop after vaccination. However, this potential relationship is essentially based on case reports, and robust pharmaco-epidemiologic data are scarce. We aimed to investigate the effect of vaccination on short-term risk of IgAV in children.

METHODS

We enrolled children <18 years old with IgAV seen in 5 pediatric departments from 2011 to 2016. Data on vaccinations administered during the year preceding IgAV onset were collected from immunization records. With a case-crossover method and by using conditional logistic-regression analyses, odds ratios (ORs) and 95% confidence intervals (CIs) were calculated by comparing vaccine exposure during the 3-month "index period" immediately preceding IgAV onset to that during 3 consecutive 3-month "control" periods immediately before the index period. Stratifications by season, year of onset, infection history, age, sex, type, or number of vaccines were performed. Sensitivity analyses used 1-, 1.5-, or 2-month index and control periods.

RESULTS

Among 167 children (mean age: 6.7 years) enrolled, 42 (25%) received ≥1 vaccine during the year before IgAV onset. Fifteen (9%) children were vaccinated during the 3-month index period as compared with 4% to 7% during the 3 control periods. The OR for IgAV occurring within the 3 months after vaccination was 1.6 (95% CI: 0.8-3.0). Analyses of IgAV risk within 1, 1.5, or 2 months of vaccination yielded ORs of 1.4 (95% CI: 0.5-3.5), 1.4 (95% CI: 0.6-3.2), and 1.3 (95% CI: 0.6-2.6), respectively. Stratifications revealed no significant association.

CONCLUSIONS

Vaccination may not be a major etiological factor of childhood IgAV.

Henoch-Schönlein purpura and drug and vaccine use in childhood: a case-control study

BACKGROUND

Henoch-Schönlein purpura (HSP) is the most common vasculitis in childhood; nevertheless, its etiology and pathogenesis remain unknown despite the fact that a variety of factors, mainly infectious agents, drugs and vaccines have been suggested as triggers for the disease. The aim of this study was to estimate the association of HSP with drug and vaccine administration in a pediatric population.

METHODS

An active surveillance on drug and vaccine safety in children is ongoing in 11 clinical centers in Italy. All children hospitalized through the local Paediatric Emergency Department for selected acute clinical conditions of interest were enrolled in the study. Data on drug and vaccine use in children before the onset of symptoms leading to hospitalization were collected by parents interview. A case-control design was applied for risk estimates: exposure in children with HSP, included as cases, was compared with similar exposure in children with gastroduodenal lesions, enrolled as controls. HSP cases were validated according to EULAR/PRINTO/PRES criteria. Validation was conducted retrieving data from individual patient clinical record.

RESULTS

During the study period (November 1999-April 2013), 288 cases and 617 controls were included. No increased risk of HSP was estimated for any drug. Among vaccines, measles-mumps-rubella (MMR) vaccine showed an increased risk of HSP (OR 3.4; 95 % CI 1.2-10.0).

CONCLUSIONS

This study provides further evidence on the possible role of MMR vaccine in HSP occurrence.

Vasculitis as an adverse event following immunization - Systematic literature review

BACKGROUND

Several types of vasculitis have been observed and reported in temporal association with the administration of various vaccines. A systematic review of current evidence is lacking.

OBJECTIVE

This systematic literature review aimed to assess available evidence and current reporting practice of vasculitides as adverse events following immunization (AEFI).

METHODS

We reviewed the literature from 1st January 1994 to 30th June 2014. This review comprises randomized controlled trials, observational studies, case series, case reports, reviews and comments regardless of vaccine and target population.

RESULTS

The initial search resulted in the identification of 6656 articles. Of these, 157 articles were assessed for eligibility and 75 studies were considered for analysis, including 6 retrospective/observational studies, 2 randomized controlled trials, 7 reviews, 11 case series, 46 case reports and 3 comments. Most of the larger, higher quality studies found no causal association between vaccination and subsequent development of vasculitis, including several studies on Kawasaki disease and Henoch-Schönlein purpura (IgA vasculitis). Smaller case series reported a few cases of vasculitis following BCG and vaccines against influenza and hepatitis. Only 24% of the articles reported using a case definition of vasculitis.

CONCLUSIONS

Existing literature does not allow establishing a causative link between vaccination and vasculitides. Further investigations were strengthened by the use of standardized case definitions and methods for data collection, analysis and presentation to improve data comparability and interpretation of vasculitis cases following immunization.

Epidemiology of immunoglobulin A vasculitis (Henoch-Schönlein): current state of knowledge

PURPOSE OF REVIEW

To review the current knowledge of epidemiological features of immunoglobulin (Ig) A vasculitis (Henoch-Schönlein) and disease etiology.

RECENT FINDINGS

The annual incidence of IgA vasculitis in the population is an estimated 3-26.7/100 000 for children and infants and 0.8-1.8/100 000 for adults. These may be conservative approximations of the true frequency because of skewed case-finding strategies. In children, the marked autumn-winter peak in incidence rates, the frequent occurrence after an upper respiratory tract infection and the short interval between disease onset in index cases and in other family members collectively point to a transmissible infectious process. A subset of adult IgA vasculitis could be related to preceding or concurrent malignancies. Despite several lines of evidence supporting the critical role of an exogenous factor in IgA vasculitis, recent progress has been made in understanding the genetic susceptibility to IgA vasculitis. Recent findings also lessened the suggestion that IgA vasculitis might be triggered by vaccination.

SUMMARY

IgA vasculitis is two to 33 times more common in children than adults and appears to have a strong environmental component, with possibly different risk factors in childhood and adulthood. Support is strengthening for a role of genetics in IgA vasculitis.

Memory B cell compartment constitution and susceptibility to recurrent lower respiratory tract infections in young children

A proportion of children have recurrent LRTIs, mostly as a result of Spn, which persist after 2 years of age. Here, we investigate, by flow cytofluorometry, the constitution of the memory B cell compartment in 90 healthy children and 49 children with recurrent LRTIs to determine if an increased susceptibility to recurrent LRTIs results from a delayed or abnormal ontogeny with poor antibody-mediated protection. Total IgA, IgM, IgG, and IgG subclasses were measured by nephelometry, as well as antipneumococcal antibodies by ELISA. Pneumococcal vaccination status was obtained. We show that the memory B cells increase between birth and 2 years of age (1.6% vs. 21.1%, P<0.001) without further significant increase noted per additional years (3-4 years old: 23.3%; 4-5 years old: 22.2%, P>0.40) to reach adult-like values (31.8±11.8%, P=0.08). Proportions of switched and IgM memory B cells were similar in children and adults. Comparatively, LRTI children had no delay in the constitution of their memory B cell compartment (2-3 years old: 26.9%; 3-4 years old: 18.2%; 4-5 years old: 26.8%, P>0.05). Their switched and IgM memory B cells were similar among age categories, and the distribution was overall similar to that of healthy controls. LRTI children had normal total and pneumococcal serotype-specific antibody values but showed a rapid waning of antipneumococcal antibody levels after vaccination. In summary, our results show that the memory B cell compartment is already similarly constituted at 2 years of age in healthy and LRTI children and thus, cannot explain the increased susceptibility to bacterial pneumonia. However, the waning of antibodies might predispose children to recurrent infections in the absence of revaccination.

Vaccines against meningococcal serogroup B disease containing outer membrane vesicles (OMV): lessons from past programs and implications for the future

The utility of wild-type outer membrane vesicle (wtOMV) vaccines against serogroup B (MenB) meningococcal disease has been explored since the 1970s. Public health interventions in Cuba, Norway and New Zealand have demonstrated that these protein-based vaccines can prevent MenB disease. Data from large clinical studies and retrospective statistical analyses in New Zealand give effectiveness estimates of at least 70%. A consistent pattern of moderately reactogenic and safe vaccines has been seen with the use of approximately 60 million doses of three different wtOMV vaccine formulations. The key limitation of conventional wtOMV vaccines is their lack of broad protective activity against the large diversity of MenB strains circulating globally. The public health intervention in New Zealand (between 2004–2008) when MeNZB was used to control a clonal MenB epidemic, provided a number of new insights regarding international and public-private collaboration, vaccine safety surveillance, vaccine effectiveness estimates and communication to the public. The experience with wtOMV vaccines also provide important information for the next generation of MenB vaccines designed to give more comprehensive protection against multiple strains.

Considerations for controlling invasive meningococcal disease in high income countries

The development of conjugate vaccines has enabled the prevention and control of Neisseria meningitidis caused by serogroups A, C, W-135 and Y. Vaccines that provide protection against a broad number of serogroup B strains likely will be available soon to enable greater control of meningococcal disease in high income countries. We present an argument for adequate post-marketing surveillance to monitor epidemiological shifts and to provide a context for the safety and reactogenicity of serogroup B vaccines, including the newer recombinant vaccines. We also offer a series of recommendations to address possible concerns about vaccine safety.

Vaccination of children and adolescents with rheumatic diseases

Children with rheumatic diseases (RDs) are at greater risk of infection because of their aberrant immunity and frequent use of immunosuppressive drugs. However, the use of vaccinations in such children is debated by many experts who think that the patients' immune response is insufficient to assure protection; some of them are also afraid that vaccines could trigger a persistent autoimmune response and lead to severe clinical problems including a relapse of the RD. This review describes the available data regarding the risks of vaccine administration, and the immunogenicity, efficacy and tolerability of the vaccines usually recommended for children with RDs. The data not only show that the schedule suggested for otherwise healthy children should be followed, but also that pneumococcal and influenza vaccinations should be strongly recommended because of the known risk of severe infections in patients with RD. However, there are areas in which further research is urgently required.

Properties and clinical performance of vaccines containing outer membrane vesicles from Neisseria meningitidis

Meningococcal outer membrane proteins have been used for over 20 years in more than 80 million doses; either as carrier protein in a Haemophilus influenzae type b (Hib) polysaccharide conjugate vaccine or as vesicle vaccine formulations against meningococcal disease. Conventional wild-type outer membrane vesicle (wtOMV) vaccines are the only formulations that have shown efficacy against serogroup B meningococcal disease. This has been demonstrated in Cuba, Norway and New Zealand; where epidemics, dominated by one particular strain or clone, were causing high rates of disease and wtOMV vaccines have been used for epidemic control. The most significant limitation for widespread use of wtOMV is that the immune response is strain-specific in infants, mostly directed against the immuno-dominant porin protein, PorA. The natural orientation of surface-exposed membrane antigens and the preservation of good physico-chemical stability are key features of OMV vaccines. The efficacy, tolerability and safety of wtOMV vaccines have been well proven. The most recent experience from New Zealand demonstrated a vaccine effectiveness of 80% for children less than 5 years of age, over a period of 24 months. Such results are encouraging for the further use of "tailor-made" OMV vaccines for epidemic control. Moreover, it provides opportunities for development of OMV vaccines with various additional cross-protective potential. There is good reason to believe that in the coming few years the "OMV-concept" will be exploited further and that a number of cross-protective "universal" antigens will be included in vaccines against serogroup B meningococcal disease. The desire to have a global vaccine strategy that enables susceptible individuals to be protected against all the relevant serogroups of meningococcal disease may become a reality.