Case Presentation: A 22-year-old female was admitted with a 5-day history of bilateral lower extremity weakness. She received influenza vaccination five weeks prior to the presentation. The patient progressed rapidly over days to quadriplegia and respiratory failure requiring intubation and mechanical ventilation. The cerebrospinal fluid analysis showed albuminocytological dissociation, and nerve conduction studies revealed an acute inflammatory demyelinating polyneuropathy. GBS was diagnosed, and she was treated with intravenous immunoglobulin and later had plasmapheresis sessions following minimal recovery. Lyme serology was positive, but the CSF Lyme PCR was negative for which she was started on Ceftriaxone. She made a gradual recovery over the next ten weeks to a near full functional status.

Discussion: GBS is a rare immune-mediated post-infectious demyelinating polyneuropathy that presents as acute flaccid paralysis. The majority of cases are preceded by Campylobacter gastroenteritis or respiratory illness (e.g., influenza, cytomegalovirus, EBV, and Mycoplasma pneumoniae). Also, Lyme disease has been implicated as a potential antecedent infection. Neuroborreliosis, a neurological manifestation of Lyme disease can present with flaccid paralysis.Post-vaccination GBS is defined by GBS occurrence within six weeks of vaccination. Influenza, polio, meningococcal, rabies, and pneumococcal vaccines have been linked to GBS. The risk of post-vaccination GBS after influenza vaccination is 1-2 cases/ million immunizations versus 17.2 cases/ million post-influenza cases. However, Influenza vaccination may have an indirect protective effect on GBS. A study reviewing hospital admissions found a significant positive correlation between influenza hospitalizations and GBS hospitalizations, but increased vaccine coverage did not lead to increased GBS hospitalizations. Therefore, effective immunization may indirectly lower GBS cases. Current recommendations encourage avoidance of flu vaccine in patients that developed GBS within six weeks of previous vaccination, due to the risk of GBS recurrence. Recurrent GBS occurs in 1-6% of cases. A small study with post-vaccination GBS patients who received flu vaccine did not report GBS recurrence. More studies are needed to assess the full benefits versus risks.

Conclusions: In our patient, since the CSF Lyme PCR was negative, Neuroborreliosis was unlikely though antecedent Lyme disease leading to GBS could not be ruled out. She likely had post-influenza vaccination GBS.