To describe a patient with recent West Nile virus (WNV) meningoencephalitis presenting with rigidity, found to have serum and CSF antibodies against glycine receptor alpha-1 subunit (GlyRα1), consistent with post-infectious stiff person spectrum disorder (SPSD). 

While development of SPSD after WNV infection has been documented with the GAD (glutamic acid decarboxylase) 65 antibody, this is, to our knowledge, the first reported case associated with the GlyRα1 antibody. 

A 54-year old previously healthy female presented with acute nausea/vomiting, diplopia, and encephalopathy. She was found to have WNV meningoencephalitis with CSF showing pleocytosis, elevated protein, and positive WNV IgM. Imaging was unremarkable. After discharging with improved mentation, she was readmitted two weeks later with jaw and right extremity spasms. MRI brain and electroencephalogram were normal. Repeat lumbar puncture showed resolving lymphocytic pleocytosis, normal protein, positive WNV IgM and IgG, and two oligoclonal bands. Symptoms were refractory to a three-day course of high-dose IV methylprednisolone, but IVIg 2g/kg provided temporary, partial relief of spasms. Her exam at follow-up revealed hyperlordosis, hyper-startle reflex, worsening of stiffness with emotional triggers, and increased tone of paraspinal, abdominal muscles, jaw, and right arm and leg. This constellation of symptoms and responsiveness to IVIg raised suspicion for SPSD. Evaluation more than four months after receiving IVIg showed positive GlyRα1 IgG in serum and CSF, and EMG showed continuous motor activity of the thoracic paraspinal muscles and evidence of co-contraction—supporting GlyRα1-mediated SPSD. Serum GlyRα1 IgG remained positive on repeat testing seven months later.  Notable negative workup includes amphiphysin, GAD65, and dipeptidyl-peptidase-like protein 6 (DPPX) antibodies in CSF and serum. The patient’s symptoms are being managed with maintenance IVIg and botulinum toxin injections. 

This first-described case of GlyRα1-mediated SPSD following WNV infection highlights the importance of thorough autoimmune investigations in post-viral patients with new neurologic symptoms.