Congenital generalized lipodystrophy type 2

Congenital generalized lipodystrophy is a rare disease characterized by a generalized lack of fat (adipose tissue) in the body. It is part of a group of diseases known as lipodystrophies. Signs and symptoms are noticed from birth (congenital) or early childhood and include high levels of fats (triglycerides) in the blood (hypertriglyceridemia) and insulin resistance (in which the body tissues are unable to respond to the hormone insulin that helps to regulate blood sugar levels) resulting in diabetes mellitus, abnormal accumulation of fat in the liver (liver steatosis) and the accumulation of fat in the heart causing a thickening of the heart muscle (hypertrophic cardiomyopathy), which can lead to a heart that does not work well (heart failure) and sudden death. Due to the almost total absence of fatty tissue and excessive growth of muscle tissue, the patients appear very muscular and have visible and prominent veins. They also have dark and thick skin in the body folds (acanthosis nigricans).

There are 4 types of the disease that are distinguished by the altered (mutated) genes and by some additional characteristic symptoms. People with type 1, caused by mutations in the AGPAT2 gene, may have cysts in the long bones of the arms and the legs after puberty. In type 2, which is caused by mutations in the BSCL2 gene, there may be intellectual disability. In type 3, caused by mutations in the CAV1 gene, affected people may have short stature and growth delay. Type 4, caused by mutations in the CAVIN1 gene, is associated with muscle weakness, developmental delay, joint anomalies, narrowing of the lower part of the stomach (pyloric stenosis), and severe heart arrhythmia that can lead to sudden death.

The inheritance of Berardinelli-Seip congenital lipodystrophy is autosomal recessive. Treatment consists on a fat restricted diet and diabetes control, and may also include leptin administration.