The key four gangliosides against which antibodies have been described are GM1, GD1a, GT1a, and GQ1b, with different antiganglioside antibodies being associated with particular features; for instance, GQ1b antibodies have been linked with Miller Fisher variant GBS and related forms including Bickerstaff encephalitis. The production of these antibodies after an infection probably is the result of molecular mimicry, where the immune system is reacting to microbial substances, but the resultant antibodies also react with substances occurring naturally in the body. After a Campylobacter infection, the body produces antibodies of the IgA class; only a small proportion of people also produce IgG antibodies against bacterial substance cell wall substances (e.g. lipooligosaccharides) that cross react with human nerve cell gangliosides. It is not currently known how this process escapes central tolerance to gangliosides, which is meant to suppress the production of antibodies against the bodys own substances. Not all antiganglioside antibodies cause disease, and it has recently been suggested that some antibodies bind to more than one type of epitope simultaneously (heterodimeric binding) and that this determines the response. Furthermore, the development of pathogenic antibodies may depend on the presence of other strains of bacteria in the bowel.It has been suggested that a poor injection technique may also cause a direct injury to the axillary nerves adjacent to the injection site in deltoid muscle that may lead to peripheral neuropathy.
There are by five characteristic features:
colonisation of endothelial cells by acid-fast bacilli
endothelial proliferation and marked thickening of vessel walls to the point of obliteration
angiogenesis
vascular ectasia
thrombosis of the superficial and mid-dermal blood vesselsThe likely pathogenesis is endothelial cell injury due to colonization/invasion followed by proliferation, angiogensis, thrombosis and vessel ectasia. Treatment
Lucios phenomenon is treated by anti-leprosy therapy (dapsone, rifampin, and clofazimine), optimal wound care, and treatment for bacteremia including antibiotics. In severe cases exchange transfusion may be helpful. == References ==