Age: 31.0
Sex: M
Vaccine: FLUX
Symptoms: Chronic inflammatory demyelinating polyradiculoneuropathy, Decreased vibratory sense, Demyelinating polyneuropathy, Gait disturbance, Hypoaesthesia
Clinical narrative: Case number PHHY2013US117544 is an initial spontaneous report received from the Vaccine Adverse Event Reporting System (the source of the case in VAERS is a literature publication, reference number: 490215) on 15 Oct 2013. This report refers to a 31-year-old male patient. He was vaccinated with Seasonal Influenza vaccine INN (manufacturer and batch number: not reported) on an unknown date. Two months (8 weeks) after influenza vaccine, the patient slowly developed progressive distal symmetric paresthesia and numbness, poor balance and gait instability. His symptoms worsened over the following 4 months. His numbness affected his hands below the wrists and legs below the knees. His balance was unsteady, especially in the dark. He was not able to run and walking short distances with minimal support, but he used a wheelchair for longer distances. Examination was notable for decreased vibration and pin sensation in his hands and feet, areflexia and mild weakness of toe extension. His gait was slow and broad based. Serum laboratory studies revealed normal vitamin B12, anti-Ro, anti-La, and serum immunofixation. MAG (myelin-associated glycoprotein) 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 degrees C. Two grams per kilogram of IVIG (intravenous immunoglobulin) was initiated 4 months after symptom onset. One gram per kilogram of IVIG was repeated every 3 weeks. Over the following 6 months, symptoms and signs improved. He continued to experience mild intermittent paraesthesias in his fingers and toes but numbness resolved. Examination revealed normal perception of vibration and pin in his hands and feet. His 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 treatment was discontinued without relapse in symptoms. The reporter concluded that vaccine-associated DADS-I (idiopathic distal acquired demyelinating symmetric neuropathy) may suggest a vaccine-triggered immunologic event directed against MAG below detectable concentrations. More likely, suspect vaccination in the patient triggered an immune response against currently unrecognized antigens and manifested as restricted CIDP in the form of DADS-I. 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. It was reported that DADS-I neuropathy could occur after vaccine. Reporter suggested consideration of this diagnosis for patients with new sensory symptoms after vaccination. It was identified that this case PHHY2013US117544 was as a duplicate to the case PHHY2013US110239 and hence all information from this case was added to the case PHHY2013US110239 and this case will deactivated. Following an internal review on 09 Sep 2014, a significant correction was performed: It was identified that this case PHHY2013US117544 was as a duplicate to the case PHHY2013US110239 and hence all the information from this case was added to the case PHHY2013US110239 and this case will deactivated.