[Hyperlipidemia in children and adolescents: diagnosis and therapy]

Severe hyperlipidemias should be diagnosed and treated even in childhood and adolescence, because vascular lipid deposition in the form of fatty streaks and progressive atherosclerotic lesions start to develop early in life. The heterozygous form of familial hypercholesterolemia found in about 1 of 500 newborn infants, and polygenic forms of hypercholesterolemia, are the most frequent forms of primary genetic hypercholesterolemia found in children. Secondary hyperlipidemias, e.g. in diabetes mellitus, hypothyroidism and renal disease, are relatively frequent in children and adolescents and need to be searched for in the diagnostic evaluation, because they can be influenced by treatment of the underlying disorder. Children and adolescents with severe forms of hyperlipidemias should be diagnosed and treated early in life. Dietary modification is the basis of treatment of affected children and can lower LDL cholesterol by about 15-20%. In patients with severe hypercholesterolemia, dietary cholesterol intake should not exceed 150 mg/day in children or 250-300 mg/day in adolescents. Even more important is a reduction of the intake of saturated fats and trans fatty acids and their replacement by polyunsaturated and particularly monounsaturated fats. Some additional lowering of LDL cholesterol may be achieved by the preferential use of vegetable over animal proteins and of complex carbohydrates over sugars. Repeated motivation, counseling and intensive practical training of the patient and family, supported by appropriate teaching materials, are essential for effective dietary treatment. Additional drug treatment is considered in children from the age of 8-9 years of age onwards if, in spite of adequate dietary modification, LDL cholesterol remains above 190 mg/dl (4.9 mmol/l), or above 160 mg/dl (3.9 mmol/l) in the presence of additional risk factors. The drugs of first choice are anion exchange resins (colestyramine or colestipol) because of their well documented efficacy and safety. More convenient to take but often somewhat less effective is beta-sitosterol. If efficacy or compliance with resins or sitosterin is unsatisfactory, fibrates (e.g. bezafibrate, fenofibrate) may be considered as a drug of second choice. Cholesterol synthesis inhibitors are not recommended for general use in children at this time.