Clinical classification and treatment of congenital and acquired lipodystrophy.

OBJECTIVE

To review the initial clinical manifestations of congenital and acquired lipodystrophy syndromes, discuss novel classifications associated with genetic mutations, and assess currently available therapeutic options for patients with lipodystrophy.

METHODS

This review is the result of the authors' collective clinical experience and a comprehensive MEDLINE literature search on the English-language literature published between January 1966 and October 2009 on "lipodystrophy." This review focuses primarily on severe dystrophy not related to human immunodeficiency virus (HIV) infection, in light of the additional scope required to cover HIV-related lipodystrophy.

RESULTS

Congenital lipodystrophy syndromes are characterized by a paucity of adipose tissue and classified on the basis of the extent of fat loss and heritability Paradoxically, they are associated with metabolic abnormalities often found in obese patients, including insulin resistance, diabetes, and severe hypertriglyceridemia. Patients with severe forms of lipodystrophy are also deficient in adipokines such as leptin, which may contribute to metabolic abnormalities. The search for molecular defects has revealed a role for genes that affect adipocyte differentiation (for example, peroxisome proliferator-activated receptor gamma), lipid droplet morphology (seipin, caveolin-1), or lipid metabolism (AGPAT2). Others (lamin A/C) are known to be associated with completely different diseases. There are also acquired forms of lipodystrophy that are thought to occur primarily attributable to autoimmune mechanisms. Recently, recombinant leptin has emerged as a useful therapy.

CONCLUSION

Lipodystrophy syndromes have advanced our understanding of the physiologic role of adipose tissue and allowed identification of key molecular mechanisms involved in adipocyte differentiation. Novel therapeutic strategies are being developed on the basis of the pathophysiologic aspects of these syndromes.