Antisulfatide neuropathy is an immune-mediated neuropathic disorder. It presents most commonly as an axonal sensory predominant polyneuropathy. However, demyelination may be seen in some cases. GALOP syndrome, a variant of antisulfatide neuropathy, is a disabling gait disorder in the elderly. Patients typically have gait ataxia and a distal sensory predominant polyneuropathy. This neuropathy is mostly demyelinating. Clinical testing for antisulfatide and anti-GALOP antibodies is useful in slowly progressive sensory or sensorimotor neuropathies affecting patients older than 50 years of age. Treatment for both involves neuropathic pain management and immunosuppression in the presence of demyelination.
Historical note and terminology
Antibodies against sulfatide, the major acidic glycosphingolipid in myelin, have been reported in a variety of systemic and neurologic disorders. These antibodies have been found in disorders such as idiopathic thrombocytopenic purpura (46), autoimmune chronic active hepatitis (43), HIV (37; 24), multiple sclerosis (40), Guillain-Barré syndrome (14; 18; 45), and chronic inflammatory demyelinating polyradiculoneuropathy (35; 28). Most studies have shown an association between highly elevated titers of antisulfatide antibodies and peripheral neuropathy (30; 22; 42; 12; 06). In the first report describing antibodies to sulfatide in neuropathy, high titers were found in patients with chronic axonal, predominantly sensory neuropathy (35). Other reports followed, but patients did not appear to constitute a single clinical syndrome, and some patients had demyelination, sometimes in association with antibodies against other myelin antigens (17; 13; 31).
Pestronk and colleagues identified extremely high titers of IgM binding to a CNS myelin antigen that co-purified with myelin associated glycoprotein in patients with gait ataxia and sensorimotor polyneuropathy. This clinical syndrome was termed the GALOP syndrome (gait disorder, autoantibody to a neural antigen, late-age onset, and polyneuropathy of mild to moderate severity) (34). The anti-CNS myelin antigen antibody was also found to cross react with both sulfatide and myelin associated glycoprotein. Pestronk’s studies suggested that titers greater than 1:10,000, with no cross-reactivity to GM1 ganglioside, have specificity for this syndrome. However, since that report, GALOP syndrome is now considered a variant of the antisulfatide syndrome, as the initially unknown antigen that co-purified with myelin associated glycoprotein was subsequently determined to be sulfatide (08; 21). Meehan and colleagues created some new and further refined antisulfatide antibodies that show additional reactivity; further study is needed to assess the utility (27).