INCREASED VLDL LEVELS AND DIMINISHED RENAL EXCRETION OF URIC-ACID IN HYPERURICAEMIC-HYPERTRIGLYCERIDEMIC PATIENTS

The objective was to study the lipoprotein levels in primary hyperuric aemic patients and to analyse their renal management of urates in orde r to check for some potential influence of altered lipid levels on the renal excretion of urates by this type of patient. Overall 115 male i ndividuals were studied in five groups, namely: 30 primary hyperuricae mic (group I); 27 primary hyperuricaemic-hypercholesterolaemic (group II); nine primary hyperuricaemic-hypertriglyceridaemic (group III); 33 primary hyperuricaemic-mixed hyperlipidaemic (group IV); and 16 normo uricaemic-normolipidaemic subjects (group C). All patients were subjec ted to blood analyses for uric acid, total triglycerides, total protei n, creatinine, high density lipoprotein (HDL) cholesterol, very low de nsity lipoprotein (VLDL) cholesterol, low density lipoprotein (LDL) ch olesterol, apoprotein (ape) AI, apoprotein B, apoprotein CII and apopr oteins CIII1 and CIII2. For urine analysis creatinine, creatinine clea rance, uric acid excretion, clearance and fractional excretion were me asured in 24 h urine samples. Mixed and pure hyperuricaemic-hypertrigl yceridaemic patients exhibited increased levels of VLDL components, de creased fractional excretion of uric acid and increased apo CIII/CII r atios. The increased levels of structural VLDL components were negativ ely (and statistically significantly) correlated with the fractional e xcretion of uric acid; this suggests a close biological relationship b etween the two parameters. Taking into account the role played by apo C in VLDL metabolism, the altered apo CIII/CII ratios found in hyperur icaemic- hypertriglyceridaemic patients (both pure and mixed) suggest that this apoprotein plays a central role in the physiopathology of th e alterations observed.