Impairment of cardiovascular autonomic reflexes in multiple symmetric lipomatosis

Multiple symmetric lipomatosis: a rare disease and its possible links to brown adipose tissue

AIM

Aim of this study is an updated review of our case series (72 patients) as well as available literature on the Multiple Symmetric Lipomatosis (MSL), a rare disease primarily involving adipose tissue, characterized by the presence of not encapsulated fat masses, symmetrically disposed at characteristic body sites (neck, trunk, proximal parts of upper and lower limbs).

DATA SYNTHESIS

The disease is more frequent in males, associated to an elevated chronic alcohol consumption, mainly in form of red wine. Familiarity has been reported and MSL is considered an autosomic dominant inherited disease. MSL is associated to severe clinical complications, represented by occupation of the mediastinum by lipomatous tissue with a mediastinal syndrome and by the presence of a somatic and autonomic neuropathies. Hyper-alphalipoproteinemia with an increased adipose tissue lipoprotein-lipase activity, a defect of adrenergic stimulated lipolysis and a reduction of mitochondrial enzymes have been described. The localization of lipomatous masses suggests that MSL lipomas could originate from brown adipose tissue (BAT). Moreover, studies on cultured pre-adipocytes demonstrate that these cells synthetize the mitochondrial inner membrane protein UCP-1, the selective marker of BAT. Surgical removal of lipomatous tissue is to date the only validated therapeutic approach.

CONCLUSIONS

MSL is supposed to be the result of a disorder of the proliferation and differentiation of human BAT cells.

Rare adipose disorders (RADs) masquerading as obesity

Rare adipose disorders (RADs) including multiple symmetric lipomatosis (MSL), lipedema and Dercum's disease (DD) may be misdiagnosed as obesity. Lifestyle changes, such as reduced caloric intake and increased physical activity are standard care for obesity. Although lifestyle changes and bariatric surgery work effectively for the obesity component of RADs, these treatments do not routinely reduce the abnormal subcutaneous adipose tissue (SAT) of RADs. RAD SAT likely results from the growth of a brown stem cell population with secondary lymphatic dysfunction in MSL, or by primary vascular and lymphatic dysfunction in lipedema and DD. People with RADs do not lose SAT from caloric limitation and increased energy expenditure alone. In order to improve recognition of RADs apart from obesity, the diagnostic criteria, histology and pathophysiology of RADs are presented and contrasted to familial partial lipodystrophies, acquired partial lipodystrophies and obesity with which they may be confused. Treatment recommendations focus on evidence-based data and include lymphatic decongestive therapy, medications and supplements that support loss of RAD SAT. Associated RAD conditions including depression, anxiety and pain will improve as healthcare providers learn to identify and adopt alternative treatment regimens for the abnormal SAT component of RADs. Effective dietary and exercise regimens are needed in RAD populations to improve quality of life and construct advanced treatment regimens for future generations.

Total and regional body composition and energy expenditure in multiple symmetric lipomatosis

AIMS

The aim of the present study was to investigate possible alterations in body composition and resting energy expenditure (REE) in type 1 multiple symmetric lipomatosis (MSL).

SUBJECTS AND METHODS

Thirteen men aged from 40 to 78 years affected by type I MSL were compared with 13 healthy control subjects. Fat mass (FM) and fat-free mass (FFM) were determined by DEXA using both standard analysis and specifically for the lipomatous region. REE was measured by indirect calorimetry.

RESULTS

FM was higher in MSL subjects at proximal arm level, but significantly lower at distal leg level than in controls (left 1.63+/-0.55 vs. 2.26+/-0.49 kg, P<0.05; right 1.63+/-0.53 vs. 2.40+/-0.54 kg, P<0.01). Arm FFM was similar in the two groups, while distal leg FFM was significantly lower in MSL cases (left: 7.8+/-1.3 vs. 8.7+/-0.8 kg, P<0.05; right: 8.0+/-1.5 vs. 9.2+/-0.9 kg, P<0.05). FFM strongly correlated with REE (r:0.86;P<0.001). REE, expressed as an absolute value and adjusted for FFM (1830+/-215 vs. 1675+/-120 kcal, P<0.05) was higher in MSL patients.

CONCLUSION

In conclusion, MSL patients had a marked FFM and FM atrophy in the lower segments of the legs and an altered energy expenditure (hypermetabolism).

Differential clinical expression of multiple symmetric lipomatosis in men and women

BACKGROUND

Multiple symmetric lipomatosis (MSL) is a rare disease characterised by the growth of uncapsulated masses of adipose tissue. MSL is associated with high ethanol intake and complicated by somatic and autonomic neuropathy and the infiltration of adipose tissue at the mediastinal level. To date, the disease is considered as largely more prevalent in men.

OBJECTIVE

To provide a detailed description of the clinical aspects of MSL in women.

PATIENTS

A total of 11 women and 58 men with MSL.

MEASUREMENTS

Morphological aspect of patient, location of the lipomatous masses, alcohol intake, extension of lipomatous tissue to the mediastinum, association with somatic and autonomic neuropathy, and metabolic profile.

RESULTS

All female patients had the obesity-like appearance of type II MSL and the most frequent locations of lipomatous masses in women were at the proximal arms (90.9%) and legs (54.5%). Very few female patients (27.3%) presented with the submental deposition of lipomatous tissue typical of both type I (97.3%; P<0.001) and type II (66.7%; P<0.05) male subjects. An extension of the lipomatus tissue around the upper airways, associated with compression or dislocation of deeply located mediastinal structures, was observed less frequently in women than in men. The presence of a high ethanol intake, the association with somatic and autonomic neuropathy and the occurrence of a characteristic metabolic pattern (high HDL-cholesterol, low LDL-cholesterol, high uric acid) were similar in men and in women.

CONCLUSIONS

Female patients with MSL had a sex-specific morphological aspect, characterised by a low occurrence of the typical 'Madelung collar' and a usual obesity-like appearance.

Multiple symmetric lipomatosis: clinical aspects and outcome in a long-term longitudinal study

BACKGROUND

Multiple symmetric lipomatosis (MSL) is a rare disease characterized by the growth of uncapsulated masses of adipose tissue. MSL is associated with high ethanol intake and complicated by somatic and autonomic neuropathy and by the infiltration of the adipose tissue at the mediastinal level. To date, the disease is considered as slowly progressive, but long-term longitudinal data are still lacking. In this study, a long-term follow-up of a large series of MSL patients is presented.

METHODS

We studied 31 patients with MSL (30 males and one female) first evaluated at our institution from 1973 to 1992. All patients were followed until 1998-1999 or until death, with a mean follow-up of 14.5+/-5.0 y (range 4-26 y). Both at baseline and during follow-up, the location and the size of the subcutaneous lipomatous fat depots, the presence and the extension of deeply localized lipomatous tissue, and the presence and the severity of both somatic and autonomic neuropathy were evaluated.

RESULTS

Eight MSL patients died during follow-up (25.8% of patients). A sudden death was proved to be the cause of death in three patients. All these three patients had severe autonomic neuropathy and none had coronary disease, acute myocardial infarction or other cardiac abnormalities. No signs or symptoms of coronary heart disease were present in the whole series. In addition to this high fatality rate, a substantial morbidity related to the occupation of the mediastinal space by the lipomatus tissue and to somatic neuropathy was also observed.

CONCLUSIONS

MSL is associated with a significant morbidity and mortality. Therefore, the definition of 'benign symmetric lipomatosis', still adopted by several authors, cannot be justified.