Low-density lipoprotein apheresis as long-term treatment for children with homozygous familial hypercholesterolemia.

OBJECTIVE: To determine the safety and efficacy of long-term dextran sulfate-affinity column low-density lipoprotein (LDL) apheresis for the treatment of children with receptor-negative homozygous familial hypercholesterolemia (HFH).

STUDY DESIGN: Two children with HFH (pretreatment cholesterol levels 22.1 to 24.7 mmol/L (ranges 850 to 950 mg/dl) began LDL apheresis treatments at ages 7 and 10 years, respectively. The LDL apheresis treatment interval was generally either 7 or 14 days; for the last 2 years of the study the treatment interval was 7 days. The patients had 167 and 188 LDL apheresis procedures during 64 and 70 months, respectively.

RESULTS: Individual procedures decreased total blood cholesterol levels by 63% to 68%. When the treatment interval was 7 days, the patients' time-averaged mean total cholesterol levels decreased to 7.3 +/- 0.65 mmol/L (280 +/- 25 mg/dl) and 6.4 +/- 0.55 mmol/L (247 +/- 22 mg/dl), respectively. Both children remained clinically well with normal growth and development. There was significant regression of xanthomas in both patients. The older patient required heart surgery for preexisting aortic stenosis and coronary ostial stenosis, but neither patient had progression of hypercholesterolemia-related cardiovascular disease. With the exception of iron (deficiency in patient 1), there was no evidence of depletion of serum components. Adverse reactions to LDL apheresis were rare and never severe.

CONCLUSIONS: Dextran sulfate-affinity column LDL apheresis is effective long-term treatment for children with receptor-negative HFH.