Autoimmune diseases have been shown to cause an increased level of C3NeF, which makes the C3bBb complex more stable. Because of this, there will be continuous stimulation of the alternative pathway, leading to excess amounts of membrane attack complex. These MACs will lead to adipocyte lysis, causing Barraquer-Simons syndrome.
Many patients have shown mutations in the LMNB2 gene, but this is not the case for all patients. Some people with mutations in this gene do not have the disease. More evidence is therefore required to conclude if this gene is linked to the disease.
Patients with this disease have a decrease of fat in the face, neck, upper extremities, trunk and upper abdomen. Some patients also have excess fat over the gluteal region, thighs and calves.