Received Apr 22, 2026
| Type | Name | Manufacturer | Dose | Lot | Route / Site |
|---|---|---|---|---|---|
| UNK | VACCINE NOT SPECIFIED (NO BRAND NAME) | UNKNOWN MANUFACTURER | UNK | — | — |
Miller Fisher Syndrome; This Literature (Spontaneous) report has been received from the authors of a published article, titled as stated above and referred to a 60-year-old Male patient. The patient's medical history included peripheral arterial disease, anemia, anal abscess/fistula, pseudoaneurysm repair, and sinus tachycardia. The patient's past medications were not reported. The patient's concurrent conditions and concomitant medications were not reported. On an unknown date, the patient was vaccinated with Pneumococcal 21-valent Conjugate Vaccine Solution for injection (dose, route of administration, lot# and expiration date were not reported) for prophylaxis. On an unknown date, 10 days after pneumococcal 21-valent conjugate vaccine administration, the patient presented to the emergency department (ED) with bilateral lower extremity weakness, numbness, paresthesia, and new onset of immobility. In the ED, the patient was ruled out for stroke, but his symptoms were still concerning for neurological disease. The patient was admitted to the medical surgical floor for neurological evaluation. Neurology assessed the patient's muscle strength using the Medical Research Council (MRC) scale for muscle strength in both upper and lower extremities on a scale from 0-5 with 0 indicating no muscle contraction and 5 indicating normal muscle power. Over the course of a single day, the patient was noted to have significant decrease in strength with two extremities scoring 2 on the MRC scale. The changes of MRC scale scores were the following: left upper extremity decreased from 4 to 3.5, right upper extremity decreased from 3.5 to 2, left lower extremity decreased from 3.5 to 2, and right lower extremity decreased from 5 to 3.5. Since this rapid deterioration in muscle strength was suspicious for Miller Fisher Syndrome (MFS), plasmapheresis and an anti-GQ1b antibody test were subsequently ordered by Neurology. Plasmapheresis with albumin was initiated on alternating days for five sessions while awaiting antibody results. The patient reported strength improvement within two days of starting plasmapheresis but did not return to baseline by the final session. Anti-GQ1b antibody testing returned negative. Notably, a small subset of MFS patients do not test positive for Anti-GQ1b antibodies. Therefore, MFS could not be ruled out by this negative result, especially considering the patient's clinical presentation. Due to the patient's improvement with plasmapheresis, Neurology continued treatment for MFS and initiated intravenous immunoglobulin (IVIG) at 0.4 g/kg IV daily for five consecutive days. Following the IVIG treatment Neurology determined that disease progression had halted. The patient had improved muscle strength but did not return to baseline and was therefore discharged to a skilled nursing facility for rehabilitation. Further assessment by Infectious Disease was conducted to evaluate the patient medical history for precipitating factors for MFS. The patient did not have any recent or active bacterial or viral infections, ruling infection out as a cause. At the time of reporting, the patient was recovering from Miller Fisher syndrome. Given the lack of any other compelling risk factors, Infectious Disease determined that PCV21 might have had precipitated the MFS. The PCV21 immunization was administered ten days prior to the onset of symptoms which was within the typical one to three weeks post-vaccination presentation of MFS in case reports. When applied to the Naranjo scale where a higher score indicates a higher probability of causality, this case obtained a score of 3 out of 10 indicating that the pneumococcal vaccination PCV21 was a possible cause of MFS in this patient. Although the patient's anti-GQ1b antibody test was negative, MFS could not be ruled out, due to the patient's response to therapy and previously reported cases of patients with MFS testing negative. A copy of the published article is attached as further documentation of the patient's experience. Lot# is being requested and will be submitted if received. Literature Report:
Medical History/Concurrent Conditions: Anal abscess; Anal fistula; Anemia; Peripheral arterial disease; Pseudoaneurysm repair; Sinus tachycardia
Test Name: Neurological assessment; Result Unstructured Data: Neurology assessed the patient's muscle strength using the Medical Research Council (MRC) scale for muscle strength in both upper and lower extremities on a scale from 0-5 with 0 indicating no muscle contraction and 5 indicating normal muscle power. Over the course of a single day, the patient was noted to have significant decrease in strength with two extremities scoring 2 on the MRC scale. The changes of MRC scale scores were the following: left upper extremity decreased from 4 to 3.5, right upper exremity decreased from 3.5 to 2, left lower extremity decreased from 3.5 to 2, and right lower extremity decreased from 5 to 3.5.; Test Name: Anti-GQ1b antibody test; Test Result: Negative