This is a spontaneous report received from contactable reporter(s) (Consumer or other non HCP) from medical information team. The reporter is the patient. An 81-year-old female patient received BNT162b2 (BNT162B2), on 22Sep2021 as dose 3 (booster), single (Batch/Lot number: unknown) at the age of 80 years for Covid-19 immunisation. The patient's relevant medical history included: "Heart surgery", start date: 2011 (not ongoing), notes: Heart surgery, triple bypass; "Dressler Syndrome" (unspecified if ongoing), reported that Dressler Syndrome diagnosis took a year to diagnose, she had Dressler Syndrome for a year, diagnosed a year after the heart surgery; "COPD", start date: 2021 (unspecified if ongoing), notes: Diagnosed last year; "Reactive airways disease", start date: 1990 (unspecified if ongoing), notes: Diagnosed in the early 1990s; "Sjogren's syndrome", start date: 2020 (unspecified if ongoing), notes: Diagnosed in 2020 maybe.; "Hashimoto's disease" (unspecified if ongoing), notes: Diagnosed probably in 1980s or 1990s. The patient's concomitant medications were not reported. Vaccination history included: Bnt162b2 (Dose: 1, Injection into left arm), administration date: Feb2020, when the patient was 79 years old, for COVID-19 immunization; Bnt162b2 (Dose: 2), administration date: Mar2020, when the patient was 79 years old, for COVID-19 immunization, reaction(s): "lymphedema", "Polymyalgia rheumatica", reported that patient was not specific about when she developed these symptoms she just mentioned that they appear after getting the 2nd dose of the vaccine. The following information was reported: LOSS OF CONSCIOUSNESS (hospitalization, medically significant), ASTHENIA (hospitalization) all with onset Mar2022, outcome "unknown" and all described as "so weak, she just passed out"; NERVOUS SYSTEM DISORDER (non-serious), outcome "unknown", described as "neurologic problems"; GAIT DISTURBANCE (non-serious), outcome "unknown", described as "She has trouble walking"; BALANCE DISORDER (non-serious), outcome "unknown", described as "Her balance is off"; TREMOR (non-serious), outcome "unknown", described as "Her right hand is shaking"; FINE MOTOR SKILL DYSFUNCTION (non-serious), outcome "unknown", described as "fine motor skill issues"; DROOLING (non-serious), outcome "unknown"; MUSCULAR WEAKNESS (non-serious), outcome "unknown", described as "she has lost use of left hand and arm". The patient was hospitalized for loss of consciousness, asthenia (start date: Mar2022, hospitalization duration: 14 day(s)). The patient underwent the following laboratory tests and procedures: Biopsy muscle: (Mar2022) Unknown results; she had a MRA: (Mar2022) Unknown results, notes: While hospitalized she had a MRA and Lumbar Puncture; Lumbar puncture: (Mar2022) vague spectrums of stuff. Therapeutic measures were taken as a result of loss of consciousness, asthenia, nervous system disorder, gait disturbance, balance disorder, tremor, fine motor skill dysfunction, drooling, muscular weakness. Clinical course was reported as, Patient indicated that she has developed several health problems and she is asking if they could be related to the Pfizer Covid19 vaccine. Patient had Booster dose on 22Sep2021, After getting the booster dose she developed neurologic problems. She has problems walking. She was not specific about when they started to appear. She just mentioned that they appear after getting the booster dose of the vaccine. Age 80 years old when the symptoms started. nowadays she is 82 years old basically, patient still declining, going from the right side to the left side, She is asking if there is information about her symptoms, can they be vaccine related and how can she stop it and asks is it reversible. Also reported as, After the booster she started having neurological issues, within a week she needed a walker, it has been down hill from there. She is wondering if this is a coincidence. She is continuing to have serious neurological issues. She needed a walker, has fine motor skill issues, now has just spent two weeks in the hospital and three weeks in rehab. She is still in rehab. She has trouble walking, her balance is off, she has lost use of left hand and arm. Her right hand is shaking. Overnight the left arm has just kind of shut down. And she has started drooling. She thought it had been a month between the booster and the neurological symptoms but realized it was only a week. She wanted to give Pfizer a call to see what was going on. When hospitalized, she had a MRA and Lumbar Puncture. Lumbar Puncture showed nothing but vague spectrums of stuff. Neurovascular surgeon is scheduling a nerve muscle biopsy, hoping to find what is causing all of this. Hospitalization: unsure of dates, she has been in rehab 2.5 weeks and the hospital 2 weeks prior, around Mar2022. She ended up in the hospital because she was so weak, she just passed out. Getting scared, the right side is beginning to show problems and she is afraid it is not reversible. Patient was only one handed. Reason for no lot number of Covid-19 Vaccine was reported as patient does not have vaccine card with her at the time of the call. The information on the batch/lot number for BNT162b2 has been requested and will be submitted if and when received. Sender's Comments: Linked Report(s): US-PFIZER INC-202200596670 similar report from same reporter, different patient, events, dose, same suspect.