Multiple symmetric lipomatosis (MSL) is characterised by the growth of fat masses symmetrically located at the neck, shoulders, deltoid and supras-capular regions, proximal segments of the arms and legs, and at the thoracic inlet, a distribution reminiscent of the location of brown adipose tissue in the foetus. The remaining subcutaneous fat layer is markedly atrophic, allowing MSL to be included in the group of LDs (Fig. 3). MSL is reported to be highly prevalent in men, but several cases of MSL in women have recently been reported .
In a series of 69 patients, the male to female ratio was 7:1. MSL appears in adulthood (range: 29-65 years), has a slowly progressive course, and is an autosomal dominant inherited disorder that primarily affects adipose tissue. Previous observations suggested lipomatous cells as brown-adipose-tissue-derived cells [46, 47]. Almost all patients have a high alcohol intake, usually red wine, suggesting a specific role for ethanol or
pharyngeal accumulation of fat tissue. In some 20% of MSL patients, fat infiltration of the pha-ryngeal and tracheal wall was found to be responsible for an obstructive apnoea syndrome during sleep. Metabolic abnormalities include hyper-triglyceridaemia and high levels of circulating HDL cholesterol. Hyperuricaemia and reduced glucose tolerance or overt diabetes occur at a frequency slightly higher than casually expected. A defect in adrenergic-stimulated lipolysis  and an increase in lipoprotein lipase activity of adipose tissue  have been demonstrated in samples of lipomatous tissue. No information is available on the metabolic activity in uninvolved subcutaneous adipose tissue, due to the fat atrophy which makes fat sampling extremely difficult.
There is evidence for a mitochondrial dysfunction in muscle fibres. Levels of respiratory-chain enzyme show a significant decrease of cytochrome-c oxidase, succinic dehydrogenase, and citrate synthase activity . Reduced mito-chondrial enzyme activity could provide the pathogenetic basis of the multisystemic clinical manifestations of MSL. Cultured MSL adipocytes synthesise UCP-1, the selective marker of brown adipocyte, but unlike in normally functioning brown fat cells, UCP-1 gene expression was not significantly induced by noradrenaline. Thus, MSL may be the consequence of a defective noradren-ergic modulation of proliferation and differentiation of brown fat cells .
other wine components in revealing a genetic defect. MSL was considered slowly progressive and benign, but a recent longitudinal study demonstrated a significant disease-specific mortality . The main complications include medi-astinal occupation by lipomatous tissue, with compression and infiltration of the muscles of the neck and mediastinal structures, and a somatic and autonomic neuropathy. Symptoms of sensory and autonomic neuropathies are frequently associated with the disease . In a 15-year follow-up of 70 patients, sudden death, in the absence of coronary heart disease, was recorded in three out of 11 patients, related to severe autonomic neuropathy . A further clinical sign of MSL is the
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