Treatment with steroids and double filtration plasmapheresis for a case of anti-GQ1b antibody-positive Bickerstaff's encephalitis

A case of Bickerstaff encephalitis with overlapping Gullian Barre syndrome in a pediatric patient treated with therapeutic plasma exchange

Bickerstaff brain stem encephalitis (BBE) is a rare brainstem disorder characterized by acute onset of ophthalmoplegia, ataxia, and altered consciousness. Guillain Barre syndrome (GBS), Miller Fischer syndrome and BBE share certain similarities such as the presence of anti-ganglioside antibodies. The use of Therapeutic Plasma Exchange (TPE) has been reserved for severe to fulminant cases of BBE mostly as an 'off label' use. The role of TPE in the overlapping syndrome of BBE and GBS has not been explored much, especially in the paediatric population. Herein, we describe a case of 2-year-old male who presented with features of BBE and later evolved to an overlapping syndrome with BBE and GBS. A multi-disciplinary team managed the patient and TPE was initiated as a part of the treatment plan. Five cycles of TPE were done from day 24 after which the patient improved. In our case, TPE was used as rescue therapy in patients with BBE overlapping with GBS. The effectiveness of TPE can be further explored as a modality in such disorders.

Diagnosis, pathogenesis and treatment of Miller Fisher syndrome and related disorders: clinical significance of antiGQ1b IgG antibody

Miller Fisher syndrome is a variant of Guillain-Barré syndrome, characterized by ophthalmoplegia, ataxia and areflexia. The antiGQ1b immunoglobulin G antibody is a specific marker of Miller Fisher syndrome and related disorders, such as Guillain-Barré syndrome with ophthalmoplegia, atypical Miller Fisher syndrome characterized by acute ophthalmoplegia or acute ataxia and Bickerstaff's brainstem encephalitis. The antiGQ1b immunoglobulin G antibody may play some important roles in the pathogenesis of Miller Fisher syndrome and related disorders. Possible mechanisms are discussed. Molecular mimicry between an infectious agent of the antecedent infection and the ganglioside may be a mechanism of the antibody production. Plasmapheresis or intravenous immunoglobulin therapy may be warranted for Miller Fisher syndrome and Bickerstaff's brainstem encephalitis, as well as Guillain-Barré syndrome with ophthalmoplegia.

Recent studies on the roles of antiglycosphingolipids in the pathogenesis of neurological disorders

Evidence is mounting to suggest a causal role of humoral immunity arising from antiglycosphingolipid (GSL) antibodies in a variety of neurological disorders. These disorders include the demyelinating and axonal forms of Guillain-Barre syndrome, multifocal motor neuropathy, chronic inflammatory demyelinating polyradiculoneuropathy, and IgM paraproteinemia. Many claims have been made regarding other neurological disorders, which should be carefully scrutinized for their validity, based on several criteria proposed in this review. These criteria include 1) characterization of the causative antigens and immunoglobulins, 2) correlation of the pathological lesions and clinical manifestation of the antigens, 3) establishment of animal models using pure GSLs as the antigens, 4) immunopathogenic mechanisms of the neurodenerative process, 5) mechanisms for the malfunctioning of blood-nerve barrier and the ensuing leakage of circulating antibodies into peripheral nerve parenchyma, and 6) the roles of anti-GSL antibodies that may cause humorally mediated nerve dysfunction and injury as well as interference with ion channel function at the node of Ranvier, where carbohydrate epitopes are located. Finally, the origin of the anti-GSL antibodies is discussed in light of the recent circumstantial evidence pointing to a molecular mimicry mechanism with infectious agents. With a better understanding of the immunopathogenic mechanisms, it will then be possible to devise rational and effective diagnostic and therapeutic strategies for the treatment of these neurological disorders.