Hyperlipoprotein(a)aemia in nephrotic syndrome

The nephrotic syndrome is frequently associated with hyperlipidaemia and hyperfibrinogenaemia, leading to an increased coronary and thrombotic risk, which may be enhanced by high lipoprotein (a) [Lp(a)] concentrations. We followed the quantitative and qualitative pattern of plasma lipoproteins over 18 months in a patient with nephrotic syndrome suffering from premature coronary artery disease and with elevated level of Lp(a) (470 mg dL-1). Analysis of kinetic parameters after heparin-induced extracorporeal plasma apheresis revealed a reduced fractional catabolic rate for both low-density lipoprotein (LDL) and Lp(a). After improvement of the nephrotic syndrome, Lp(a) decreased to 169 mg dL-1 and LDL concentrations were normalized. The decrease of Lp(a) was associated with an increase in plasma albumin concentrations. Analysis of apo(a) isoforms in the patient showed the presence of isoform S2 (alleles 10 and 19). Consequently, the authors' present strategy is to normalize the elevated Lp(a) and fibrinogen levels. For this purpose heparin-mediated extracorporeal LDL precipitation (HELP) apheresis is a promising regimen, helping to reduce the thrombotic risk and prevent coronary and graft atherosclerosis as well as the progression of glomerulosclerosis in our patient.

Acute changes in concentrations of apolipoproteins A-I, B, C-II and lipoprotein(a) in serum covering the period from directly before to 48 hours after chronic haemodialysis

This study reports the changes in total cholesterol, triacylglycerols, apolipoproteins A-I, B, C-II and (a) before, directly after and 48 hours after chronic renal dialysis on 46 non-selected patients (20 male, 26 female; time since first dialysis 1-203 months (median 22 months), median age 52 years, range 25-82 years). Thirty six of the 46 patients (17 men and 19 women) suffered from hypertension. There were no sex-linked differences in any analyte except cholesterol, which was significantly higher in women than in men at all times. The apolipoproteins were determined with immunoluminometric assays. Apolipoprotein C-II was determined as the apolipoprotein C-II: apolipoprotein B complex. Lipoprotein(a) was determined using two antibodies directed against apolipoprotein(a). Significant increases (p < 0.05) in serum concentrations before and after dialysis were seen for all analytes with the exception of cholesterol (no significant change) and apolipoprotein C-II (significant decrease). The median increases were: cholesterol 5%, triacylglycerols 28%, apolipoprotein A-I 19%, apolipoprotein B 11%, apolipoprotein C-II -39%, lipoprotein(a) [all patients 21%, <300 mg/l 8%, > 300 mg/l 163%]. The values 48 hours after dialysis were not significantly different from the value before dialysis for cholesterol (-5%), apolipoprotein B (0%) and lipoprotein(a) (-2% - all patients). Statistically significant lower concentrations of apolipoprotein C-II (-28%) (p < 0.01) and triacylglycerols (-19%) (p < 0.01) were observed, but not investigated further. The behaviour of lipoprotein(a) was not correlated with any of the other analytes except triacylglycerols, where a statistically significant negative correlation was seen in all groups.(ABSTRACT TRUNCATED AT 250 WORDS)