To the best of our knowledge, this is only the second case of severe AIDP related to PEG-IFNα2a, which developed at week five of IFNα2a therapy initiated for hepatitis C virus infection and where the gradual reintroduction of IFN was safe and without any residual neuromuscular deficits. This evidence concerns the gene IFNA2 and Guillain-Barre syndrome, familial.