Teaching Video NeuroImage: Near complete ophthalmoplegia in GQ1b antibody-positive Miller Fisher: Video and MRI correlation

Clinical Characterization of Anti-GQ1b Antibody Syndrome in Childhood

Objective: To delineate the comprehensive clinical features of anti-GQ1b antibody syndrome in childhood. Methods: The clinical data of children diagnosed with anti-GQ1b antibody syndrome at two Chinese tertiary pediatric neurology centers were collected and analyzed. We also conducted a systematic literature review on anti-GQ1b antibody syndrome in children. Results: This study included 78 children with anti-GQ1b antibody syndrome, consisting of 12 previously unreported cases from the two Chinese centers. The median onset age was 10 years (range, 2-18 years). The most common phenotype was acute ophthalmoparesis (32%), followed by classic Miller Fisher syndrome (15%), and Bickerstaff brainstem encephalitis (12%). External ophthalmoplegia (48%), sensory disturbance (9%), and bulbar palsy (9%) were the three most frequent onset symptom manifestations. Brain or spinal lesions on MRI and abnormal recordings by nerve conduction study were present in 18% (12/68) and 60% (27/45) of cases, respectively. There was CSF albuminocytologic dissociation in 34% of the patients (23/68). IV immunoglobulin alone or combined with steroids or plasma exchange was administered to 58% of patients (42/72). We did not find a significant correlation between early improvement up to 3 months and age onset and phenotype. All patients showed different degrees of recovery, and 81% (57/70) had complete recovery within 1 year. Conclusions: Acute ophthalmoparesis and classic Miller Fisher syndrome are the most common phenotypes of anti-GQ1b antibody syndrome in childhood. The majority of patients show good response to immunotherapy and have favorable prognosis.

From ophthalmoplegic migraine to cranial neuropathy

Ophthalmoplegic migraine (OM)/recurrent painful ophthalmoplegic neuropathy (RPON) is a rare disease consisting of recurrent unilateral headache accompanied or followed by ipsilateral ophthalmoplegia. Because MRI findings suggest neuropathy and the relationship to typical migraine remains unclear, the disease has been renamed from "ophthalmoplegic migraine" to "recurrent painful oculomotor neuropathy" in the third edition of the International Classification of Headache Disorders (ICHD). However, it remains a fact that most cases of OM/RPON described in the literature have a history of migraine and that the headache during OM/RPON often has migrainous features. A more detailed clinical description of the headache during OM/RPON and additional results from imaging and possibly histology will be needed to better understand the pathophysiology of the disease and its relationship to typical migraine.

Autoimmune disorders affecting both the central and peripheral nervous system

Various case series of patients with autoimmune demyelinating disease affecting both the central and peripheral nervous system (CNS and PNS), either sequentially or simultaneously, have been reported for decades, but their frequency is considerably lower than that of the "classical" neurological autoimmune diseases affecting only either CNS or PNS, such as multiple sclerosis (MS), chronic inflammatory demyelinating polyneuropathy (CIDP) or Guillain-Barré-Syndrome (GBS), and attempts to define or even recognize the former as a clinical entity have remained elusive. Frequently, demyelination started with CNS involvement with subsequent PNS pathology, in some cases with a relapsing-remitting course. Three potential mechanisms for the autoimmune etiology of these conditions can be discussed: (I) They could be caused by a common autoimmunological reactivity against myelin antigens or epitopes present in both the central and peripheral nervous system; (II) They could be due to a higher general susceptibility to autoimmune disease, which in some cases may have been caused or exacerbated by immunomodulatory treatment, e.g. b-interferon; (III) Their co-occurrence might be coincidental. Another example of an autoimmune disease variably involving the central or peripheral nervous system or both is the overlapping and continuous clinical spectrum of Fisher syndrome (FS), as a variant of GBS, and Bickerstaff brainstem encephalitis (BBE). Recent data from larger patient cohorts with demonstration of common autoantibodies, antecedent infections, and results of detailed clinical, neuroimaging and neurophysiological investigations suggest that these three conditions are not separate disorders, but rather form a continuous spectrum with variable central and peripheral nervous system involvement. We herein review clinical and paraclinical data and therapeutic options of these disorders and discuss potential underlying common vs. divergent immunopathogenic mechanisms.

Palatal insufficiency as isolated sign of GQ1b antibody syndrome

Antiganglioside GQ1b antibodies mediate a continuum of disorders with overlapping features, fostering the concept of anti-GQ1b antibody syndrome. We present a patient whose palatal insufficiency was the only clinical sign of postinfectious GQ1b antibody syndrome. Cerebral magnetic resonance imaging confirmed involvement of the glossopharyngeal nerve and vagus nerve bilaterally, revealing gadolinium enhancement of both nerves bilaterally and thickening of the left nervus vagus. Magnetic resonance imaging may help in diagnosing postinfectious GQ1b antibody syndrome, especially at early stages and in monosymptomatic patients. Early diagnosis may lead to early therapy, resulting in a milder disease course by preventing further deterioration leading to the ataxia and ophthalmoplegia usually observed in patients with postinfectious GQ1b antibody syndrome.