Bell's Palsy; Acute inflammatory demyelinating polyneuropathy (AIDP); This literature case was received from other healthcare professional on 28-Nov-2022 and concerned a 73-year-old, male patient.   The aim of this conference abstract was to report an unusual presentation of acute inflammatory demyelinating polyneuropathy following influenza vaccination.  The patient's concurrent conditions included chronic myeloid leukemia and alcohol abuse. The patient's concomitant medications included dasatinib used for chronic myeloid leukemia. The patient's historical vaccines included multiple influenza vaccines (brands not specified) after which the patient had no complications.  On an unspecified date, the patient was vaccinated with influenza vaccine (brand not specified; dose, route of administration, anatomical location, and indication: not reported). The batch number was not reported.   On an unspecified date, an unknown amount of time after receiving influenza vaccine, the patient developed bilateral hands numbness.   On an unspecified date, two weeks later, the numbness progressed to the patient's bilateral feet.   On an unspecified date, the patient experienced left facial droop and numbness. The patient was diagnosed with Bell's Palsy and discharged home.   On an unspecified date, the patient's weakness continued to progress, and he started using a wheelchair for mobility compared to no device at baseline. The patient was admitted to Outpatient Physiatry Clinic for suspected acute inflammatory demyelinating polyneuropathy after negative magnetic resonant imaging (MRI) of brain and cervical spine. The patient received immunoglobulin intravenously (IVIG) with mild improvements of strength.   On an unspecified date, the multiple investigations were performed. Sensory conduction studies of bilateral sural, right median, and right superficial radial nerves were absent. Motor conduction studies of bilateral common peroneal and tibial nerves showed significantly increased onset latency and decreased conduction velocity with temporal dispersion, while the distal amplitudes were decreased to a lesser extent. Bilateral tibial F waves had increased minimum latency and decreased persistence. Motor conduction of right ulnar nerve had significantly increased onset latency and decreased conduction velocity in a patchy distribution with temporal dispersion. Needle electromyogram (EMG) was unremarkable except for 1+ fibrillations and positive sharp waves in the right gastrocnemius. Electrodiagnostic studies were consistent with acute inflammatory demyelinating polyneuropathy (AIDP). Due to the unusual presentation of AIDP as descending numbness and weakness, initial diagnosis was delayed, however was confirmed on electrodiagnostic testing with hallmark signs of AIDP.  The outcome of the events was not reported.  The reporter did not provide causality assessment.   Both events were assessed as serious due to the seriousness criteria of hospitalization. The event of acute inflammatory demyelinating polyneuropathy was additionally assessed as serious due to the seriousness criteria of disability. Additionally, both events were considered to be medically significant by a Physician within Seqirus's Pharmacovigilance and Risk Management Department.  Company comment: A 73-year-old, male patient was vaccinated with the suspect product influenza vaccine. On an unspecified day after vaccination the patient developed bilateral hands numbness. Two weeks later, the numbness progressed to the patient's bilateral feet. On an unspecified date the patient developed facial droop and numbness and was diagnosed with Bell's Palsy. On an unspecified date, the patient's weakness continued to progress, and he started using a wheelchair. Electrodiagnostic studies were consistent with acute inflammatory demyelinating polyneuropathy (AIDP). Due to the unusual presentation of AIDP as descending numbness and weakness, initial diagnosis was delayed, however was confirmed on electrodiagnostic testing with hallmark signs of AIDP. Causality for the events Bell's palsy and Guillain-Barre syndrome is unassessable due to unclear temporal relationship. Limited information precludes assessment of Brighton Collaboration criteria for Bell's palsy and Guillain-Barre syndrome.; Sender's Comments: A 73-year-old, male patient was vaccinated with the suspect product influenza vaccine. On an unspecified day after vaccination the patient developed bilateral hands numbness. Two weeks later, the numbness progressed to the patient's bilateral feet. On an unspecified date the patient developed facial droop and numbness and was diagnosed with Bell's Palsy. On an unspecified date, the patient's weakness continued to progress, and he started using a wheelchair. Electrodiagnostic studies were consistent with acute inflammatory demyelinating polyneuropathy (AIDP). Due to the unusual presentation of AIDP as descending numbness and weakness, initial diagnosis was delayed, however was confirmed on electrodiagnostic testing with hallmark signs of AIDP. Causality for the events Bell's palsy and Guillain-Barre syndrome is unassessable due to unclear temporal relationship. Limited information precludes assessment of Brighton Collaboration criteria for Bell's palsy and Guillain-Barre syndrome.