Guillain-Barré syndrome/ Acute inflammatory demyelinating polyradiculoneuropathy; Asymmetric weakness (arms MRS 3/5; legs MRC 1/5); loss of deep tendon reflexes; Initial information received on 19-Aug-2021 regarding an unsolicited valid serious case issued from a literature article.  Literature citation: Reporter: Guillain-Barre syndrome is infrequent among recipients of the BNT162b2 mRNA COVID-19 vaccine; Journal: Clinical immunology; Year: 2021 ;230; Pages: 1-4; Digital object identifier: https://doi.org/10.1016/j.clim.2021.108818.  This case involves a 81 years old female patient who had Guillain-Barre syndrome/ acute inflammatory demyelinating polyradiculoneuropathy (Guillain-Barre syndrome), asymmetric weakness (Muscular weakness) and loss of deep tendon reflexes (areflexia) when received vaccines INFLUENZA VACCINE and TOZINAMERAN [COVID-19 MRNA VACCINE BNT162B2].  The patient's was tobacco user.  The patient's past vaccination and family history were not provided.  The patient did not have history or ongoing COVID-19 and no preceding diarrhea for less than or equal to 4 weeks. At the time of the event, the patient had ongoing hypertension and chronic kidney disease having haemodialysis.  On an unknown date, the patient received a dose of suspect INFLUENZA VACCINE produced by unknown manufacturer lot number not reported via an unknown route at an unknown administration site for prophylactic vaccination.  On an unknown date, the patient received a first dose of suspect COVID-19 MRNA VACCINE BNT162B2 not produced by Sanofi Pasteur, lot number not reported via an unknown route at an unknown administration site for prophylactic vaccination.  On an unknown date the patient developed a serious Guillain-Barre syndrome/ acute inflammatory demyelinating polyradiculoneuropathy (Guillain-Barre syndrome), asymmetric weakness (Muscular weakness) [arms Modified Rankin Scale (MRS) 3/5; legs Medical Research Council Muscle Strength Grading System (MRC) 1/5] and loss of deep tendon reflexes (areflexia) 40 days following the administration of INFLUENZA VACCINE and 03 days following the administration of COVID-19 MRNA VACCINE BNT162B2.  These events were assessed as medically significant. The patient's hospitalized length of stay was 10 days and then patient was discharged for home.  Laboratory data was reported as: Admission Guillain-Barre syndrome (GBS) disability score was 4.  Discharge GBS disability score was 4.  Brighton Collaboration group certainty level for GBS was level 1.  Respiratory insufficiency score (EGRIS) was 3.  Findings/days (GBS) symptoms to lumbar puncture: Proteins: 414 mg/ dL, white blood cell (WBC): 0, glucose: 65 mg/dL/13 days.  Electrophysiological variant was acute inflammatory demyelinating polyradiculoneuropathy. 1-week modified Erasmus GBS outcome score (mEGOS) was 5.  It was reported as while both vaccines INFLUENZA VACCINE COVID-19 MRNA VACCINE BNT162B2 may have synergistically triggered an autoimmune response, this observed association seems to be coincidental, as millions of healthy people have received both vaccines in short succession without a subsequent outbreak of GBS.  The patient was treated with intravenous IMMUNOGLOBULINS NOS (IMMUNOGLOBULIN I.V) for Guillain-Barre syndrome.  The event outcome was unknown for all events.  The causal relationship for event with the INFLUENZA VACCINE and COVID-19 MRNA VACCINE BNT162B2 was not reported.  Batch number has been requested for suspect product for this case.; Sender's Comments: This case concerns a 81-year-female patient who experienced Guillain-Barre syndrome after vaccination with INFLUENZA VACCINE (unknown manufacturer) and COVID-19 MRNA VACCINE BNT162B2 (other manufacturer). The time to onset is compatible. The patient's was tobacco user, had ongoing hypertension and chronic kidney disease and hemodialysis. There is no further information on patient's health condition at the time of vaccination, concomitants medications and other relevant laboratory data was not provided. Based upon the reported information, the role of the individual suspect vaccine cannot be assessed.