Behaviour Of Exogenous Heparin In Patients With Nephrotic Syndrome

Behaviour of exogenous heparin was studied in 35 subjects after intravenous injection of 50 u/kg heparin : 10 healthy control adults, 8 control children with normal hemostatic system, 17 children with nephrotic syndrome without renal insufficiency. Blood samples were collected before injection and 15 min, 30 min, 60 min and 120 min later, for the following tests : APTT, thrombin time, automatised heparin assay using a chromogenic substrate (S-2238). Heparin behaviour was assessed by two criteria : recovery (plasma heparin level) 15 min after the injection ; halflife of recovered heparin. Results were compared with the following parameters : WBC and platelet count ; serum albumin and lipids ; plasma antithrombin III, α2 macroglobulin and fibrinogen ; histological findings when available

In nephrotic children, mean heparin recovery was lower than in the control groups, very poor or even negligible in 9/17 cases. Heparin halflife was close to 37 min in most patients, shorter than in healthy controls (mean : 46 min), and dramatically decreased in 4 cases.

No significant correlation was observed between the observed heparin behaviour and the considered parameters ; sensitivity to heparin was notably unrelated to plasma antithrombin III level. Insensitivity was observed in three patients with amyloidosis.