Lcat Deficiency

LCAT (lecithin-cholesterol acyltransferase) deficiency is a rare lipoprotein metabolism disorder characterized clinically by corneal opacities, and sometimes renal failure and hemolytic anemia, and biochemically by severely reduced HDL cholesterol.

Epidemiology

Prevalence of LCAT deficiency is unknown. About 125 cases have been reported to date worldwide. Most cases were reported in Europe, Japan and Canada.

Clinical description

Age of onset is variable but most patients are diagnosed during adulthood. Two familial forms of LCAT deficiency have been reported: familial LCAT deficiency (FLD, see this term) characterized by corneal opacities, anemia and renal insufficiency, and Fish-eye disease (FED, see this term) characterized by corneal opacities and sometimes atherosclerosis.

Etiology

LCAT deficiency is caused by deficient or absent catalytic activity of the LCAT enzyme, which catalyzes the formation of cholesterol esters in lipoproteins and is encoded by the LCAT gene (16q22.1). Accumulation of unesterified cholesterol in the body, e.g. in the cornea, erythrocytes and kidneys, is thought to underlie the clinical manifestations. To date, more than 85 mutations in the LCAT gene have been identified. LCAT deficiency follows an autosomal recessive pattern of inheritance.