Age: 31.0
Sex: M
Vaccine: FLUX
Symptoms: Demyelinating polyneuropathy, Gait disturbance, Hypoaesthesia, Immunoglobulin therapy, Immunology test normal
Clinical narrative: This case was reported in a literature article and described the occurrence of distal acquired demyelinating symmetric neuropathy in a 31-year-old male subject who was vaccinated with Influenza vaccine (manufacturer unspecified). The subject was previously healthy. On an unspecified date the subject received unspecified dose of Influenza vaccine (unknown route, unknown injection site). Lot number was not provided. 2 months after vaccination with Influenza vaccine, the subject developed slowly progressive distal symmetric paresthesias and numbness, poor balance, and gait instability. His symptoms worsened over the following 4 months. At his nadir, numbness affected his hands below the wrists and legs below the knees. Balance was unsteady, especially in the dark. He was not able to run. Walking short distances could be achieved with minimal support, but he used a wheelchair for longer distances. The subject was diagnosed with distal acquired demyelinating symmetric neuropathy (DADS). This case was assessed as medically serious by GSK. Examination was notable for decreased vibration and pin sensation in his hands and feet, areflexia, and mild weakness of toe extension. Gait was slow and broad based. Serum laboratory studies revealed normal vitamin B12, anti-Ro, anti-La, and serum immunofixation. MAG antibodies were absent. Cerebral spinal fluid demonstrated mild albuminocytologic dissociation (protein, 55 mg/dL). Nerve conduction studies showed prolonged distal latency in median, ulnar, peroneal, and tibial motor nerves (30%-50% above upper limit of normal) and median, ulnar, and sural sensory nerves. The F waves were absent (median) or mildly prolonged. Partial conduction block was present in the right ulnar nerve forearm segment (30% amplitude reduction). Martin-Gruber anastomosis was not present. Limb temperature was more than 32 deg C. The subject was treated with normal immunoglobulin (IVIG) 4 months after onset of symptoms. Over the following 6 months, symptoms and signs improved. He continued to experience mild intermittent paresthesias in his fingers and toes but numbness resolved. Examination revealed normal perception of vibration and pin in his hands and feet. Reflexes normalized. Gait was narrow, and he could perform tandem gait without difficulty. He was able to resume exercise, and reported running 3 consecutive miles at 8 hours and 30 minutes per mile pace. IVIG was discontinued without relapse in symptoms. Vaccine-associated distal acquired demyelinating symmetric neuropathy (DADS) may suggest a vaccine-triggered immunologic event directed against myelin associated glycoprotein below detectable concentrations. More likely, we suspect vaccination in this subject triggered an immune response against currently unrecognized antigens and manifested as restricted chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) in the form of demyelinating symmetric neuropathy. Vaccine-associated CIDP is a rare but poorly characterized event that should not discourage at-risk individuals from being vaccinated. Nonetheless, vaccine safety and public reassurance rely on rapid detection and treatment of adverse outcomes. DADS neuropathy can occur after vaccine. We suggest consideration of this diagnosis for patients with new sensory symptoms after vaccination.