Endocrine Abstracts

JOINT3689

Introduction: Familial hypercholesterolemia (FH) is a genetic disorder primarily caused by mutations in the gene encoding the LDL receptor (90%), apolipoprotein B (5%), or PCSK9 (1%), leading to elevated LDL cholesterol levels and a significantly increased risk of premature atherosclerotic cardiovascular disease. We report the case of a 24-year-old female with homozygous FH managed with PCSK9 inhibitors.

Case Report: The patient, a 24-year-old woman, had been followed since the age of 4 for homozygous FH. Her brother underwent coronary artery bypass grafting at the age of 27 for severe coronary artery disease. She presented with ischemic heart disease and severe aortic insufficiency. Surgical interventions, including coronary artery bypass and valve replacement, were deferred due to poorly controlled hypercholesterolemia despite treatment with rosuvastatin 20 mg/day and ezetimibe 10 mg/day. Physical examination revealed tendon xanthomas on the hands, elbows, and knees. Body mass index (BMI) was 31.17 kg/m², and blood pressure was 130/70 mmHg. Laboratory findings included total cholesterol (TC) at 9.28 g/l, LDL cholesterol (LDLc) at 8.03 g/l, and triglycerides (TG) at 1.1 g/L. Rosuvastatin was increased to 40 mg/day, and acetylsalicylic acid 100 mg/day was added. Cholestyramine was not tolerated. After 3 months of treatment, TC was 8.12 g/l, and LDLc remained at 8 g/L. Consequently, PCSK9 inhibitors were initiated at the dose of 420 mg subcutaneous injections monthly. This resulted in a 36% reduction in TC and a 41% reduction in LDLc.

Conclusion: This case highlights the complexity of managing homozygous familial hypercholesterolemia and the crucial role of PCSK9 inhibitors in improving lipid profiles. This treatment can reduce atherogenic risk and improve life expectancy in these high-risk young patients.