Introduction:
Neurofascin-155 (NF-155) antibodies target neurofascin, a protein localized at the nodes of Ranvier, and cause an autoimmune nodopathy that primarily affects young adults. In rare cases, central nervous system demyelination can occur. Here we present a pediatric patient with combined central and peripheral demyelination associated with NF-155 antibodies.
Case Description:
A 7-year-old girl presented with vomiting with abdominal pain followed by dizziness, drooling, and dysarthria over 3 weeks. Mental status was normal. Cranial nerve examination showed down-beating nystagmus, left eyelid ptosis, left tongue deviation, absent pinprick sensation in left V3 distribution, reduced pinprick in legs to mid-shin, and hyporeflexia. Over a few days, generalized weakness progressed to include respiratory failure requiring intubation and left peripheral 7th and bilateral 9th, 10th, 11th, 12th cranial nerve palsies. Imaging demonstrated an expansile non-enhancing lesion centered in the dorsal left medulla. Cerebral spinal fluid showed lymphocytosis with elevated protein. Electrophysiology showed a length-dependent, demyelinating, sensorimotor polyneuropathy. Neuropathy panel was positive for IgM and IgG Neurofascin-155 antibodies. Treatment included IV immunoglobulin 2 g/kg and high dose (150 mg/kg) intravenous methylprednisolone followed by a gradual corticosteroid taper. Five months after initial presentation, she made significant recovery with a strong symmetric face, near normal palate elevation with mild pooling secretions, normal sensation, and significant improvement in strength with run velocity and jumping distance nearly equivalent to her unaffected twin.
Conclusion:
This child with Neurofascin-155 antibody associated autoimmune nodopathy with rapid progression shows an unusually severe presentation with nearly complete response to treatment with IVIG and steroids.