Berardinelli's lipodystrophy, also known as Berardinelli-Seip syndrome, describes a rare congenital disorder that causes generalized loss of subcutaneous fat tissue (lipatrophy) from birth on.
Due to the lack of functional adipocytes, lipid deposition into other tissues occurs, mainly in muscle and liver. It comes to hypertriglyceridemia, hepatomegaly and acromegaly. Characteristic is above all the extreme insulin resistance of those affected, which manifested clinically as diabetes mellitus in the second decade of life.
The complications include the development of hypertrophic cardiomyopathy, the development of fatty liver with hepatic dysfunction, muscle hypertrophy, various hormonal disorders (including accelerated infant growth and premature puberty), and bone cysts with spontaneous fractures.
Two causative genes have been identified so far: AGPAT2 (9q34) and BSCL2 (11q13). AGPAT2 encodes a key enzyme in triglyceride biosynthesis (1-acylglycerol-3-phosphate-O-acyltransferase-2) and BSCL2 for the protein seipin. Most patients with BSCL2 mutations have mental retardation. The inheritance of the mutations is autosomal recessive.
The clinical picture together with the biochemical changes leads to the diagnosis. A proof of mutation can confirm the diagnosis. Important differential diagnoses include laminopathies and Parry-Romberg syndrome.
A causal treatment is not known, the focus is on the treatment of diabetes. It should be followed a low-fat diet. The prognosis is determined by the accompanying complications. The occurrence of hypertrophic cardiomyopathy is associated with increased morbidity and early mortality.