Liver disorders characterized by prolonged bile stasis are often associated with the accumulation of an abnormal
lipoprotein,
lipoprotein-X (LP-X), in plasma. LP-X is separated in the
low-density lipoprotein (
LDL) density range, but lacks
apolipoprotein B and does not interact with the
LDL receptor; LP-X can cause
hyperlipidemia, cutaneous
xanthomas, and worsening of arterial disease. We report the case of a patient with severe
cholestasis, markedly elevated plasma
cholesterol levels (26.8 to 31.5 mmol/L), mainly due to a massive accumulation of LP-X in plasma, and diffuse
xanthomas. To reduce the
elevated cholesterol levels, the patient was given extracorporeal treatment aimed at removing atherogenic
lipoprotein (
LDL-
apheresis).
LDL-
apheresis was performed at weekly or bi-weekly intervals, either by a semi-selective technique using filters with a defined pore diameter (double filtration, DF) or by a more selective technique using
dextran-sulfate-
cellulose (DSC) columns able to bind
LDL. The semi-selective DF technique proved more effective than DSC, removing 48% of total
cholesterol (compared to 30% with DSC), and lowering
cholesterol levels to 11.1 mmol/L in 6 weeks. DF removed both
LDL and LP-X from plasma, whereas DSC selectively decreased the
LDL content. The reduction of plasma
cholesterol levels was associated with a complete regression of the
xanthomas, supporting DF
apheresis as a first-choice treatment for patients with massive LP-X accumulation due to
cholestasis.