autoimmunity in patients with gad-ab and their relatives

Conditions: Neurological Syndromes With GAD-Ab; Organ-specific Autoimmune Diseases

Summary: a group of poorly studied immune-mediated neurological syndromes are associated with antibodies against glutamic-acid decarboxylase (gad-ab). gad is the rate-limiting enzyme for the synthesis of gamma aminobutyric acid (gaba) from glutamate and is expressed by inhibitory neurons of the central nervous system. neurological syndromes with anti-gad antibodies (gad-ab) are often non-paraneoplastic. they mainly include limbic encephalitis (le), cerebellar ataxia (ca) and stiff-person syndrome (sps). although the pathogenic role of gad-ab is controversial, most patients have high serum levels and gad-ab are also detected in the cerebrospinal fluid (csf) along with other inflammatory abnormalities such as oligoclonal bands. gad-ab may also be present in the serum of t1dm patients, as pancreatic beta cells also express gad, but usually at much lower titers than those of neurological patients. organ-specific autoimmune diseases, such as t1dm and autoimmune thyroid disease, are common among patients with gad-ab and neurological syndromes and in their relatives, suggesting a shared genetic predisposition to autoimmune disorders. this is also supported by family reports of neurological syndromes with gad-ab and some hla associations described in sps. the aim of this study is to describe the different autoimmune organ-specific diseases present in patients with gad-ab and their relatives, along with to identify families with higher aggregation of autoimmune diseases and establish potential ways of inheritability.

a group of poorly studied immune-mediated neurological syndromes are associated with antibodies against glutamic-acid decarboxylase (gad-ab). gad is the rate-limiting enzyme for the synthesis of gamma aminobutyric acid (gaba) from glutamate and is expressed by inhibitory neurons of the central nervous system. neurological syndromes with anti-gad antibodies (gad-ab) are often non-paraneoplastic. they mainly include limbic encephalitis (le), cerebellar ataxia (ca) and stiff-person syndrome (sps). although the pathogenic role of gad-ab is controversial, most patients have high serum levels and gad-ab are also detected in the cerebrospinal fluid (csf) along with other inflammatory abnormalities such as oligoclonal bands. gad-ab may also be present in the serum of t1dm patients, as pancreatic beta cells also express gad, but usually at much lower titers than those of neurological patients. organ-specific autoimmune diseases, such as t1dm and autoimmune thyroid disease, are common among patients with gad-ab and neurological syndromes and in their relatives, suggesting a shared genetic predisposition to autoimmune disorders. this is also supported by family reports of neurological syndromes with gad-ab and some hla associations described in sps. the aim of this study is to describe the different autoimmune organ-specific diseases present in patients with gad-ab and their relatives, along with to identify families with higher aggregation of autoimmune diseases and establish potential ways of inheritability.

Eligibility criteria:
inclusion criteria: * patient with a well-known neurological syndrome associated with gad-ab (le, ca, sps) * patient with an csf positive for gad-ab; * patient witn an age \> 18 years old. exclusion criteria: * patient with absence of complete clinical data. * patient with csf not tested or negative for gad-ab