title: Immune-mediated steroid-responsive epileptic spasms and epileptic encephalopathy associated with VGKC-complex antibodies.
abstract: Autoantibodies that bind to voltage-gated potassium-channel complex proteins (VGKC-complex antibodies) occur frequently in adults with limbic encephalitis presenting with cognitive impairment and seizures. Recently, VGKC-complex antibodies have been described in a few children with limbic encephalitis, and children with unexplained encephalitis presenting with status epilepticus. We report a case of infantile-onset epileptic spasms and developmental delay compatible with epileptic encephalopathy. Our patient was a female infant, aged 4 months at presentation. She had evidence of immune activation in the central nervous system with elevated cerebrospinal fluid neopterin and mirrored oligoclonal bands, which prompted testing for autoantibodies. VGKC-complex antibodies were elevated (201 pmol/L, normal<100), but extended antibody testing, including leucine-rich glioma-inactivated 1 (LGI1) and contactin-associated protein 2 (CASPR2), was negative. The patient showed a partial response to steroid treatment, which was started late in the disease course. On review at 13 months of age, her development was consistent with an age of 5 to 6 months. These results suggest that VGKC-complex antibodies might represent a marker of immune therapy responsiveness in a subgroup of patients with infantile epileptic encephalopathy.
authors: Neuroimmunology Group, Institute for Neuroscience and Muscle Research, The Children's Hospital at Westmead, University of Sydney, Sydney, New South Wales, Australia.
authors: Jehan
authors: J
authors: Suleiman
authors: Tanja
authors: T
authors: Brenner
authors: Deepak
authors: D
authors: Gill
authors: Christopher
authors: C
authors: Troedson
authors: Adriane J
authors: AJ
authors: Sinclair
authors: Fabienne
authors: F
authors: Brilot
authors: Angela
authors: A
authors: Vincent
authors: Bethan
authors: B
authors: Lang
authors: Russell C
authors: RC
authors: Dale
mesh_terms: D001323:Autoantibodies / Q000134:cerebrospinal fluid; D002675:Child, Preschool; D004569:Electroencephalography; D004827:Epilepsy / Q000150:complications / Q000188:drug therapy / Q000276:immunology; D005260:Female; D006801:Humans; D008607:Intellectual Disability / Q000150:complications / Q000188:drug therapy / Q000276:immunology; D065768:Lennox Gastaut Syndrome; D008279:Magnetic Resonance Imaging; D024642:Potassium Channels, Voltage-Gated / Q000276:immunology*; D013036:Spasms, Infantile / Q000150:complications / Q000188:drug therapy / Q000276:immunology; D013256:Steroids / Q000627:therapeutic use*
chemical_list: D001323:Autoantibodies; D024642:Potassium Channels, Voltage-Gated; D013256:Steroids