Received Apr 29, 2026
| Type | Name | Manufacturer | Dose | Lot | Route / Site |
|---|---|---|---|---|---|
| COVID19 | COVID19 (COVID19 (PFIZER-BIONTECH)) | PFIZER\BIONTECH | UNK | — | — |
Miller Fisher Syndrome; This is a literature report. Herein, the authors report a serologically confirmed case of MFS in a 51-year-old man, detailing his clinical course, diagnostic findings, and functional recovery following the administration of a Pfizer SARS-CoV-2 bivalent mRNA vaccine. A 51-year-old previously independent, right-handed, male with a past medical history of GERD, benign prostatic hyperplasia (BPH), chronic right L5 radiculopathy, and right carpal tunnel syndrome presented to the hospital on March 7th, 2025, with five days of progressive neurological symptoms. His history was notable for receiving a Pfizer SARS-CoV-2 bivalent vaccine (2VCOV-mRNA, 30mcg/0.3mL) 10 days prior to symptom onset. He reported no immediate post-vaccination illness. The patient's illness began with ascending numbness in his hands and feet. This was followed two days later by progressive ataxia, rendering him unable to sit or stand without assistance. He also developed diplopia on leftward gaze and dizziness upon standing. On admission, neurological examination revealed an awake and alert patient with significant dysarthria. Cranial nerve assessment was remarkable for a left eyelid ptosis and bilateral facial weakness. He was areflexic in all four limbs. He exhibited severe truncal and appendicular ataxia. He had no bowel or bladder incontinence during his disease course. His respiratory status was monitored closely, with a negative inspiratory force (NIF) of -60 and a vital capacity (VC) of 2.7 L. During his admission, he developed tachycardia and slight variations in blood pressure, suggesting a mild dysautonomia. An extensive diagnostic workup was performed. Magnetic resonance imaging (MRI) of the brain and entire spine revealed no acute intracranial or spinal cord pathology that could explain his symptoms, showing only chronic degenerative changes consistent with his known history. A lumbar puncture demonstrated the classic finding of cytoalbuminologic dissociation, with a protein level of 61 mg/dL and a white blood cell count of 3 cells/uL. Critically, a serum anti-ganglioside antibody panel, performed on March 6, was positive for anti-GQ1b IgG antibodies, confirming the diagnosis of MFS. Serologies for Lyme disease, syphilis (VDRL), and West Nile virus were negative. Electromyography (EMG) was performed, which noted subtle electrophysiologic findings compatible with an early acute demyelinating neuropathy, including mildly prolonged right ulnar and tibial F-waves and a prolonged distal CMAP duration in the right peroneal nerve. The study also confirmed his known chronic right L5 radiculopathy and right median mononeuropathy at the wrist. The patient was treated with a five-day course of intravenous immunoglobulin (IVIg) from March 7 to March 11. He was discharged from the acute care hospital on March 19 and admitted to an inpatient acute rehabilitation facility. There, he received intensive physical, occupational, and speech therapy for three hours a day, five days a week. His respiratory status improved, and his ptosis and diplopia resolved. After exhausting his insurance-covered days at this facility, he still required further therapy to gain more independence, specifically with stair training for his third-story apartment. He was therefore discharged to a sub-acute rehabilitation facility for continued therapy prior to returning home. Conclusion: This case illustrates how an immune response, plausibly triggered by a bivalent COVID-19 vaccine, can lead to the production of anti-GQ1b antibodies and result in acute, debilitating neurological deficits. Early recognition and timely immunotherapy are crucial for facilitating recovery. This case reinforces the need for vigilance in patients who develop new-onset ataxia and ophthalmoplegia, emphasizing the importance of considering MFS in the differential diagnosis even in the absence of a preceding infection. Follow-up (21Apr2026):This is a literature report. This is a follow-up report based on the receipt of the publication; the case has been updated to include additional information identified in the publication. Updated information included: Reporter and literature information, other relevant history, lab data, suspect product details, and event details were updated.; Sender's Comments: Based on the information available and plausible temporal association, the causal relationship between the reported event MILLER FISHER SYNDROME and suspect drug BNT162B2 cannot be excluded. The impact of this report on the benefit/risk profile of the Pfizer product is evaluated as part of Pfizer procedures for safety evaluation, including the review and analysis of aggregate data for adverse events. Any safety concern identified as part of this review, as well as any appropriate action in response, will be promptly notified to Regulatory Authorities, Ethics Committees and Investigators, as appropriate.
Medical History/Concurrent Conditions: Benign prostatic hyperplasia; GERD; Hospitalization (five days); Lumbar radiculopathy; Neurologic symptoms; Unilateral carpal tunnel syndrome
Test Date: 20250306; Test Name: serum anti-GQ1b antibody/serum anti-ganglioside antibody panel/anti-GQ1b IgG antibodies; Test Result: Positive ; Comments: confirming the diagnosis of MFS.; Test Date: 202503; Test Name: blood pressure; Result Unstructured Data: Test Result:slight variations; Comments: On admission; Test Date: 202503; Test Name: Serologies for Lyme disease; Test Result: Negative ; Test Date: 202503; Test Name: cerebrospinal fluid; Result Unstructured Data: Test Result:showing cytoalbuminologic dissociation; Test Date: 202503; Test Name: Electromyography (EMG); Result Unstructured Data: Test Result:noted subtle electrophysiologic; Comments: findings compatible with an early acute demyelinating neuropathy, including mildly prolonged right ulnar and tibial F-waves and a prolonged distal CMAP duration in the right peroneal nerve. The study also confirmed his known chronic right L5 radiculopathy and right median mononeuropathy at the wrist.; Test Date: 202503; Test Name: Heart rate; Result Unstructured Data: Test Result:tachycardia; Comments: On admission; Test Date: 202503; Test Name: inspiratory force (NIF); Result Unstructured Data: Test Result:-60; Comments: On admission; Test Date: 202503; Test Name: lumbar puncture; Result Unstructured Data: Test Result:demonstrated the classic finding of; Comments: cytoalbuminologic dissociation, with a protein level of 61 mg/dL and a white blood cell count of 3 cells/µL.; Test Date: 202503; Test Name: Magnetic resonance imaging (MRI) of the brain and entire spine; Result Unstructured Data: Test Result:revealed no acute intracranial or spinal cord; Comments: pathology that could explain his symptoms, showing only chronic degenerative changes consistent with his known history.; Test Date: 202503; Test Name: Magnetic resonance imaging (MRI) of the brain and entire spine; Result Unstructured Data: Test Result:revealed no acute intracranial or spinal cord; Comments: pathology that could explain his symptoms, showing only chronic degenerative changes consistent with his known history.; Test Date: 202503; Test Name: Cranial nerve assessment; Result Unstructured Data: Test Result:remarkable for a left eyelid ptosis and bilateral; Comments: facial weakness. On admission; Test Date: 202503; Test Name: neurological examination; Result Unstructured Data: Test Result:revealed an awake and alert patient with; Comments: significant dysarthria. On admission; Test Date: 202503; Test Name: protein level; Test Result: 61 mg/dl; Test Date: 202503; Test Name: Serologies for syphilis (VDRL); Test Result: Negative ; Test Date: 202503; Test Name: vital capacity (VC); Test Result: 2.7 l; Comments: On admission; Test Date: 202503; Test Name: Serologies for West Nile virus; Test Result: Negative ; Test Date: 202503; Test Name: white blood cell count; Result Unstructured Data: Test Result:3 cells/uL