Hepatitis B vaccine related-myelitis?

Central Demyelinating Diseases after Vaccination Against Hepatitis B Virus: A Disproportionality Analysis within the VAERS Database

INTRODUCTION

Hepatitis B (HB) vaccination programs were set up worldwide in the early 1990s. Despite their major focus on reducing the burden of HB infection, they have seldom achieved the targeted population coverage in most countries, including the USA, with around 24.5% of adults being vaccinated against HB. Among proposed reasons for this is the persisting doubt about a possible link between HB vaccination and the occurrence of cases of multiple sclerosis (MS).

OBJECTIVE

Our objective was to evaluate a potential safety signal between MS and HB vaccination. We conducted a disproportionality analysis (DPA) using the cases reported to the Vaccine Adverse Event Reporting System (VAERS).

METHODS

We calculated the proportional reporting rate (PRR) and reporting odds ratio (ROR) of MS having occurred within the 120 days following HB immunization in adults aged 19-49 years when compared with other vaccines using the reports recorded in the VAERS database. Both ratios were estimated globally and then according to the origin of reports (USA vs. non-USA). We then performed a sensitivity analysis using a broader category of demyelinating events.

FINDINGS

MS cases following HB vaccination were more likely to originate from outside the USA and to be reported before 2000 than those associated with other immunizations. All computed ratios were found to be statistically significant, with PRRs ranging from 3.48 to 5.56 and RORs ranging from 3.48 to 5.62. When considering the geographical origin, similar RORs were obtained for both US and non-US cases.

CONCLUSION

In VAERS, MS cases were up to five times more likely to be reported after an HB vaccination than after any other vaccination. Since DPA is mainly suited for hypothesis generation, further studies evaluating the nature of the link between MS and HB vaccination would be of considerable importance.

Vaccine-associated inflammatory diseases of the central nervous system: from signals to causation

PURPOSE OF REVIEW

As the most cost-effective intervention in preventive medicine and as a crucial element of any public health program, vaccination is used extensively with over 90% coverage in many countries. As approximately 5-8% of the population in developed countries suffer from an autoimmune disorder, people with an autoimmune disease are most likely to be exposed to some vaccines before or after the disease onset. In fact, a number of inflammatory disorders of the central nervous system have been associated with the administration of various vaccines. These adverse events, be they spurious associations or genuine reactions to the vaccine, may lead to difficulties in obtaining public trust in mass vaccination programs. There is, thus, an urgent need to understand whether vaccination triggers or enhances autoimmune responses.

RECENT FINDINGS

By reviewing vaccine-associated inflammatory diseases of the central nervous system, this study describes the current knowledge on whether the safety signal was coincidental, as in the case of multiple sclerosis with several vaccines, or truly reflected a causal link, as in narcolepsy with cataplexy following pandemic H1N1 influenza virus vaccination.

SUMMARY

The lessons learnt emphasize a central role of thorough, ideally prospective, epidemiological studies followed, if the signal is deemed plausible or real, by immunological investigations.

Acute Disseminated Encephalomyelitis following Vaccination against Hepatitis B in a Child: A Case Report and Literature Review

Acute disseminated encephalomyelitis (ADEM) is an inflammatory demyelinating disease of the central nervous system, which has been associated with several vaccines such as rabies, diphtheria-tetanus-polio, smallpox, measles, mumps, rubella, Japanese B encephalitis, pertussis, influenza, and the Hog vaccine. Here, we presented a case of 12-year-old child who suffered from ADEM three weeks after hepatitis B vaccination. He was admitted to our hospital with symptoms of weakness of limbs, high fever, and alteration of consciousness. Some abnormalities were also found in CSF. Treatment with high-dose corticosteroids and intravenous immunoglobulin had significant effect, with marked improvement of the clinical symptoms and the results of CSF. The findings of MRI also detected some abnormal lesions located in both brain and spinal cord. The clinical features, the findings of CSF and MRI, and therapeutic effect may contribute to such diagnosis of ADEM.

Transverse myelitis and vaccines: a multi-analysis

Transverse myelitis is a rare clinical syndrome in which an immune-mediated process causes neural injury to the spinal cord. The pathogenesis of transverse myelitis is mostly of an autoimmune nature, triggered by various environmental factors, including vaccination. Our aim here was to search for and analyze reported cases of transverse myelitis following vaccination. A systematic review of PubMed, EMBASE and DynaMed for all English-language journals published between 1970 and 2009 was preformed, utilizing the key words transverse myelitis, myelitis, vaccines, post-vaccination, vaccination and autoimmunity. We have disclosed 37 reported cases of transverse myelitis associated with different vaccines including those against hepatitis B virus, measles-mumps-rubella, diphtheria-tetanus-pertussis and others, given to infants, children and adults. In most of these reported cases the temporal association was between several days and 3 months, although a longer time frame of up to several years was also suggested. Although vaccines harbor a major contribution to public health in the modern era, in rare cases they may be associated with autoimmune phenomena such as transverse myelitis. The associations of different vaccines with a single autoimmune phenomenon allude to the idea that a common denominator of these vaccines, such as an adjuvant, might trigger this syndrome.

Systemic polyarteritis nodosa following hepatitis B vaccination

The authors report a patient who developed systemic polyarteritis nodosa two months after hepatitis B vaccination and review the literature concerning this vaccination and the development of autoimmune conditions, mainly vasculitis. A 14-year-old boy who had no relevant previous history and who was not taking any drugs presented with a livedo reticularis, fever, loss of weight, testicular pain, and paresthesias two months after receiving the third dose of a hepatitis B vaccination. Inflammatory parameters (ESR and CRP) were high. The patient met the ACR diagnostic criteria for polyarteritis nodosa. He received corticosteroids and immunosuppressants and showed improvement. After reviewing the 27 cases of vasculitis after hepatitis B vaccination reported in the current literature, the authors suggest that, in some cases, vaccination may be the triggering factor for vasculitis in individuals with a genetic predisposition. Physicians should be aware of this possible association.

Disseminated encephalomyelitis in children

The advent of MRI has contributed to increase the interest and awareness in childhood white matter disorders. A major priority is to distinguish transient and self-limited demyelinating syndromes like disseminated encephalomyelitis (DEM), from life-long diseases like multiple sclerosis (MS). However, the term DEM has been inconsistently applied across studies due to the lack of clear clinical and neuroimaging diagnostic criteria. The present review summarizes the available literature on DEM in children, outlines the main clinical and neuroimaging features at presentation, pathogenesis and outcome, and its differentiation from other conditions with acute impact in the CNS. The recently proposed clinical definitions for monophasic disseminated encephalomyelitis and its relapsing variants are discussed, and controversies surrounding the diagnosis of MS in children are addressed.

Vaccines for viral diseases with dermatologic manifestations

Vaccines against infectious diseases have been available since the 1800s, when an immunization strategy against smallpox developed by Jenner gained wide acceptance. Until recently, the only vaccination strategies available involved the use of protein-based, whole killed, and attenuated live virus vaccines. These strategies have led to the development of effective vaccines against a variety of diseases with primary or prominent cutaneous manifestations. Effective and safe vaccines now used worldwide include those directed against measles and rubella (now commonly used together with a mumps vaccine as the trivalent MMR), chickenpox, and hepatitis B. The eradication of naturally occurring smallpox remains one of the greatest successes in the history of modern medicine, but stockpiles of live smallpox exist in the United States and Russia. Renewed interest in the smallpox vaccine reflects concerns about a possible bioterrorist threat using this virus. Yellow fever is a hemorrhagic virus endemic to tropical areas of South America and Africa. An effective vaccine for this virus has existed since 1937, and it is used widely in endemic areas of South America, and to a lesser extent in Africa. This vaccine is recommended once every 10 years for people who are traveling to endemic areas. Advances in immunology have led to a greater understanding of immune system function in viral diseases. Progress in genetics and molecular biology has allowed researchers to design vaccines with novel mechanisms of action (eg, DNA, vector, and VLP vaccines). Vaccines have also been designed to specifically target particular viral components, allowing for stimulation of various arms of the immune system as desired. Ongoing research shows promise in prophylactic and therapeutic vaccination for viral infections with cutaneous manifestations. Further studies are necessary before vaccines for HSV, HPV, and HIV become commercially available.