Multiple Symmetric Lipomatosis

Abstract

Multiple symmetric lipomatosis (MSL) was first described by Brodie and Madelung in patients with a typical symmetrical submental deposition of fat (Madelung’s collar). MSL is characterized by the formation of multiple nonencapsulated lipomas with sparing of distal arms and legs. A history of high ethanol intake is recorded in the large majority of MSL patients. Upper airway compression and dislocation, dyslipidemia, hyperuricemia, and impaired glucose tolerance have been frequently reported. Because fat cells are smaller than normal in this disorder, lipomata were attributed to neoformation of adipocytes that originate in brown fat. Somatic and autonomic neuropathies are often present; the peripheral neuropathy might be attributed to alcoholism, but the pathologic findings suggest it is part of the syndrome. An association between MSL and mitochondrial dysfunction has been reported, mainly represented by a reduced cytochrome C oxidase activity, ragged-red fibers, and multiple deletions in mtDNA (Table 77.1). Some patients with the myoclonic epilepsy with ragged-red fibers (MERRF) syndrome and the 8344A > G mutation had cervical lipomas resembling those of MSL.