Vaccines and Guillain-Barré syndrome

Vaccines and the risk of Guillain-Barré syndrome

The role of vaccination in the development of Guillain-Barré syndrome (GBS) is controversial, although cases of GBS have been reported following a wide range of vaccines. A nested case-control study was conducted between January 2011 and December 2015 in three Chinese cities. Four controls were matched to a case by gender, age, address and index date. An independent expert committee validated the diagnoses of cases and controls according to the Brighton Collaboration GBS case definition. Data on vaccinations were obtained from computerized vaccination records. Causal relations were assessed by conditional logistic regression. 1056 cases of GBS and 4312 controls were included in the analyses. Among paediatric and adult population, adjusted ORs for GBS occurrence within 180 days following vaccination were 0.94 (95% CI 0.54-1.62) and 1.09 (95% CI 0.88-1.32), respectively. No increased risk of GBS was detected for vaccination against hepatitis B, influenza, hepatitis A, varicella, rabies, polio(live), diphtheria, pertuss(acellular), tetanusis, measles, mumps, rubella, Japanese Encephalitis, and meningitis vaccines. Adjusted ORs for the recurrence of GBS after vaccination among paediatric and adult population were 0.85 (95% CI 0.07-9.50) and 1.18 (95% CI 0.49-2.65), respectively. In this large retrospective study, we did not find evidence of an increased risk of GBS and its recurrence among either paediatric (≤ 18 years) or adult (> 18 years) individuals within the 180 days following vaccinations of any kind, including influenza vaccination.

Vaccine-preventable diseases, vaccines and Guillain-Barre' syndrome

Guillain-Barré syndrome (GBS) is an acute, immune-mediated polyradiculoneuropathy. Infections and vaccines have been hypothesized to play a role in triggering GBS development. These beliefs can play a role in reducing vaccination coverage. In this report, data concerning this hypothesis are discussed. It is shown that an association between vaccine administration and GBS has never been proven for most of debated vaccines, although it cannot be definitively excluded. The only exception is the influenza vaccine, at least for the preparation used in 1976. For some vaccines, such as measles/mumps/rubella, human papillomavirus, tetravalent conjugated meningococcal vaccine, and influenza, the debate between supporters and opponents of vaccination remains robust and perception of vaccines' low safety remains a barrier to achieving adequate vaccination coverage. Less than 1 case of GBS per million immunized persons might occur for these vaccines. However, in some casesimmunization actually reduces the risk of GBS development. In addition, the benefits of vaccination are clearly demonstrated by the eradication or enormous decline in the incidence of many vaccine-preventable diseases. These data highlight that the hypothesized risks of adverse events, such as GBS, cannot be considered a valid reason to avoid the administration of currently recommended vaccines.

Acute lower motor neuron tetraparesis

Flaccid nonambulatory tetraparesis or tetraplegia is an infrequent neurologic presentation; it is characteristic of neuromuscular disease (lower motor neuron [LMN] disease) rather than spinal cord disease. Paresis beginning in the pelvic limbs and progressing to the thoracic limbs resulting in flaccid tetraparesis or tetraplegia within 24 to 72 hours is a common presentation of peripheral nerve or neuromuscular junction disease. Complete body flaccidity develops with severe decrease or complete loss of spinal reflexes in pelvic and thoracic limbs. Animals with acute generalized LMN tetraparesis commonly show severe motor dysfunction in all limbs and severe generalized weakness in all muscles.

Acute polyradiculoneuritis: Guillain-Barré syndrome

Guillain-Barré syndrome (GBS) is an acute, immune-mediated, postinfectious polyneuropathy with symmetrical ascending weakness, diminished deep tendon reflexes, and nonspecific sensory symptoms. CSF protein is raised with normal or only slightly elevated cell count. Based on electrophysiological and pathological findings, a demyelinating variant (acute inflammatory demyelinating polyneuropathy, AIDP) and an axonal variant (acute motor axonal neuropathy, AMAN) can be differentiated. Molecular mimicry with common epitopes between infective agents and peripheral nerves is discussed as an important pathophysiological principle. The symptoms progress for a mean of 10 days (up to 4 weeks) and after a plateau of 1-2 weeks remit spontaneously. At the height of the disease 60% of children are unable to walk and 10-15% need artificial ventilation. Treatment with plasmapheresis and intravenous immunoglobulins (IVIG) has been proven in placebo-controlled studies in adults with severe disease to speed up recovery significantly. In children, mostly open studies have shown similar treatment effects, although their spontaneous course is frequently less severe. Children with GBS should be treated with IVIG when they have lost the ability to walk, or when they are still deteriorating significantly and are expected to lose the ability to walk. The long-term prognosis is more favorable than that in adults. Whereas 25% of patients maintain mild neurological symptoms and signs, disability in the long term is very rare and usually due to complications such as myelitic involvement or chronic inflammatory demyelinating polyneuropathy (CIDP).

Clinical features, pathogenesis, and treatment of Guillain-Barré syndrome

Guillain-Barré syndrome (GBS) is an important cause of acute neuromuscular paralysis. Molecular mimicry and a cross-reactive immune response play a crucial part in its pathogenesis, at least in those cases with a preceding Campylobacter jejuni infection and with antibodies to gangliosides. The type of preceding infection and patient-related host factors seem to determine the form and severity of the disease. Intravenous immunoglobulin (IVIg) and plasma exchange are effective treatments in GBS; mainly for practical reasons, IVIg is the preferred treatment. Whether mildly affected patients or patients with Miller Fisher syndrome also benefit from IVIg is unclear. Despite medical treatment, GBS often remains a severe disease; 3-10% of patients die and 20% are still unable to walk after 6 months. In addition, many patients have pain and fatigue that can persist for months or years. Advances in prognostic modelling have resulted in the development of a new and simple prognostic outcome scale that might also help to guide new treatment options, particularly in patients with GBS who have a poor prognosis.

Infections and vaccinations preceding childhood Guillain-Barré syndrome: a prospective study

INTRODUCTION

We performed a prospective, multicentre study in children with Guillain-Barré syndrome (GBS), diagnosed according to international criteria, to investigate the frequency and aetiology of antecedent diseases. All infections and vaccinations occurring within a 6-week period prior to the onset of GBS were documented.

MATERIALS AND METHODS

Stool cultures, standardised serological investigations and PCR analyses for 24 different infective agents were performed. Serological findings were regarded as significant if specific immunoglobulin (Ig)M or IgA antibodies were detected, if the IgM enzyme immunoassay or immunfluorescence assay findings were confirmed by immunoblot, if complement fixation test titres rose fourfold or if geometric titres were more than threefold higher than in uninfected control persons. Ninety-five children with GBS were included in the study over a 40-month period. Preceding events were reported in 82%.

RESULTS

Microbiological studies carried out on 84 patients resulted in a probable diagnosis in 46 (55%). Coxsackieviruses (15%), Chlamydia pneumoniae (8%), cytomegalovirus (7%) and Mycoplasma pneumoniae (7%) were the most frequently involved agents. Serological evidence of a Campylobacter jejuni infection was found in six patients (7%). Eight children had been vaccinated during the 6 weeks preceding the onset of GBS; in six of these children concomitant infectious diseases were reported, and in one child the time between vaccination and GBS was extremely short.

CONCLUSION

We conclude that, in contrast to adults, Campylobacter spp. does not seem to play a major role in childhood GBS in German-speaking countries. The aetiology of antecedent diseases is distributed over a wide spectrum of paediatric infectious diseases. Most of the children who had been vaccinated showed concomitant infectious diseases, thus obscuring the causative role for GBS.

Epidemiologic features of Guillain-Barré syndrome in São Paulo, Brazil

INTRODUCTION

There are few epidemiologic studies concerning Guillain-Barré syndrome (GBS). Due to difficulties with definition and lack of a standard diagnostic test of reference, GBS is not easy to study epidemiologically. We evaluate some epidemiological features of GBS in a sample of cases treated at a tertiary hospital in São Paulo, Brazil.

METHOD

We retrospectively reviewed all cases of GBS with hospitalization in Santa Marcelina hospital, over the period of January 1995 through December 2002.

RESULTS

Ninety-five cases were included in this study. Fifty-five were men and forty women, with a proportion of 1.4 men to 1 woman. The age ranged from 1 to 83 years with a mean age at onset of 34 years. GBS was less frequently observed below 15 years (18.9%) and above 60 years (16.9%). The highest frequency was observed in patients aged 15 to 60 years old (66.2%). The annual incidence rate was 0.6 cases/100,000 people. There was a highest frequency of cases during the months of September through March (62.1%).

CONCLUSION

Our data differs from that of other epidemiological studies in that we did not observe a bimodal distribution in age and found a seasonal pattern in hotter months.

Risk of Guillain-Barré syndrome after measles-mumps-rubella vaccination

OBJECTIVE

To assess the postulated causal association between measles-mumps-rubella (MMR) vaccination and Guillain-Barré syndrome (GBS).

STUDY DESIGN

Active retrospective study based on linkage of the nationwide hospital discharge register with individual vaccination records. All patients hospitalized for treatment of GBS in Finland between November 1982 and December 1986 were included in the study.

RESULTS

During the study period, 189 patients were hospitalized for treatment of GBS, and approximately 630,000 vaccine recipients received 900,000 doses of MMR vaccine; 24 of the 189 patients represented the prevailing target population for MMR vaccination, of whom 20 were vaccinated. MMR vaccination did not cause any increase over the background incidence of GBS, and no clustering of cases of GBS occurred at any time point after administration of MMR vaccine. The interval between vaccination and onset of symptoms of GBS exceeded the designated risk period of 6 weeks in all cases, varying from 80 days to years. MMR vaccination after recovery from GBS did not cause relapses of the illness. Respiratory or gastrointestinal tract infection predated the onset of GBS by 3 to 30 days in 20 (83%) of the 24 patients.

CONCLUSIONS

No causal association seems to prevail between MMR vaccination and GBS.

Safety of routine childhood vaccinations. An epidemiological review

Immunisations have been one of the most cost-effective public health interventions in human history. Despite remarkable progress, several challenges face immunisation programs worldwide. Paradoxically, despite vaccines' clear effectiveness in reducing risks of diseases that were previously widely prevalent and caused substantial morbidity and mortality, current vaccination policies have become increasingly controversial due to concerns about vaccine safety. Vaccines, like other pharmaceutical products, are not entirely risk-free. While most known adverse effects are minor and self-limited, some vaccines have been associated with very rare but serious adverse effects. Because such rare effects are often not evident until vaccines come into widespread use, ongoing surveillance programs to monitor vaccine safety are needed. Such monitoring will be essential if the public is to accept the increasing number of new vaccines made possible by biotechnology. The interpretation of data from vaccine safety research is complex and is associated with some uncertainty. Effectively communicating this uncertainty and continuing to improve understanding of rare risks and risk factors are essential for "mature" immunisation programs to maintain public confidence in immunisations.

Guillain-Barré Syndrome and Vaccination: Usually Unrelated

With the rapid pace of immunologic research, it is more important than ever for readers to understand rational immunodiagnosis, immunoprophylaxis, and immunotherapy. This column is intended to help you carry out proper immunologic drug use in your practice.

Guillain-Barré syndrome

Guillain-Barré syndrome (GBS) is viewed as a reactive, self-limited, autoimmune disease triggered by a preceding bacterial or viral infection. Campylobacter jejuni, a major cause of bacterial gastroenteritis worldwide, is the most frequent antecedent pathogen. It is likely that immune responses directed towards the infecting organisms are involved in the pathogenesis of GBS by cross-reaction with neural tissues. The infecting organism induces humoral and cellular immune responses that, because of the sharing of homologous epitopes (molecular mimicry), cross-react with ganglioside surface components of peripheral nerves. Immune reactions against target epitopes in Schwann-cell surface membrane or myelin result in acute inflammatory demyelinating neuropathy (85% of cases); reactions against epitopes contained in the axonal membrane cause the acute axonal forms of GBS (15% of cases). Care for such patients may be challenging, yet the prognosis overall is favourable. Optimal supportive care and anticipation and prevention of complications are the mainstay of therapy. Admission to the intensive-care unit is necessary in 33% of patients who require intubation and assisted ventilation. Immunomodulation with infusions of IgG or plasma exchange treatments foreshorten the disease course.