Guillain-Barré syndrome and hepatitis A: lack of association during a major epidemic

[Guillain-Barré syndrome associated with acute hepatitis A-A case report and literature review]

A 44-year-old female developed acute hepatitis A (HA) 5 weeks after ingesting raw oysters. She developed ascending motor weakness, bilateral peripheral facial nerve palsy, and bulbar symptoms. A diagnosis of demyelinating Guillain-Barré syndrome (GBS) was made on the basis of her clinical manifestations and the results of a nerve conduction study. The patient showed improvement following combination treatment with intravascular immunoglobulin and high dose methylprednisolone. No antibodies against specific gangliosides, sulfated glucuronyl paragloboside (SGPG), or sulfatide were detected. HA virus (HAV) RNA was isolated from her serum and its full-length genome sequence was determined. It revealed a homology of 99.9% or more with HAV genotype IA (HAV-IA) of the 2014 outbreak. No mutant virus RNA was detected.

Neuromuscular complications of hepatitis A virus infection and vaccines

The hepatitis A virus (HAV) infects millions of people worldwide every year. Case histories report on various acute neuropathy syndromes in the context of acute HAV infection, but any causal link has not been established. Epidemiological data also cast doubt on the importance of HAV as a trigger for Guillain-Barré syndrome. The virtual absence of a chronic HAV-infected state likely explains the rare occurrence of extrahepatic immune-mediated diseases, including an absence of chronic autoimmune neuromuscular disorders. Several vaccines against HAV provide effective protection against natural infection. Isolated case histories report on an unconvincing association between HAV vaccination and neuropathy. Medical and epidemiological data show insufficient evidence to support a causal relationship between HAV vaccines and neuropathy syndromes. Aluminum hydroxide, a HAV vaccine adjuvant, is considered a trigger of the macrophagic myofasciitis syndrome. This review concludes that it seems unnecessary to routinely consider HAV infection or vaccination as triggers of neuromuscular diseases.

The epidemiology of Guillain-Barré syndrome

Population-based studies of Guillain-Barré syndrome (GBS) give crude average annual incidence rates varying from 0.4 to 1.7 per 100,000 population. The reported incidence is influenced by the diagnostic criteria adopted as well as the thoroughness of case-finding. Variations in these account for some of the lack of uniformity between different studies. Data from the Mayo Clinic based on National Institute of Neurological Disorders and Stroke diagnostic criteria and thorough ascertainment methods gave a crude incidence of 1.7 per 100,000 per year (x 10(-5]. Incidence was higher in females (2.3 x 10(-5] than males (1.2 x 10(-5] as well as in older compared to younger people (3.2 x 10(-5) over age 60 and 0.8 x 10(-5) under age 18, respectively). The disease reached a nadir after onset at 8 days on average, and the illness lasted an average of 12 weeks. Most patients (75%) recovered completely. Recent epidemiological studies of GBS suggest no clear secular trend. Incidence does fluctuate with time but not clearly with season. In virtually all studies "triggering" factors are implicated, but they appear to be diverse, making it less likely, from an epidemiological perspective, that a single antigen is of etiological importance in GBS.