[Optimization of enoxaparin dose in the prevention of coagulation in the circuits of hemodialysis: results of a multicenter study]. / Optimisation de la dose d'énoxaparine (Lovenox) dans la prévention de la coagulation des circuits d'hémodialyse: résultats d'une étude multicentrique.

In order to define the optimal dosage of a low molecular weight enoxaparine (Lovenox) in the prevention of clotting in extracorporeal circulation during hemodialysis, a multicentre trial was conducted in 72 patients dialysed in seven hemodialysis units. During three weeks, these patients received as antithrombic treatment a single injection of enoxaparine at the beginning of the session. The initial dose fixed by previous data concerning dialysis with high hemorrhagic risks patients was 0.5 mg/kg (50 U1 Anti-Xa/kg). According to the evaluation of thrombotic manifestations during a 4 hour dialysis, the dosage was progressively increased if necessary for each patient. For 41% patients, the initial dose of 0.5 mg/kg was maintained along the whole study; 59% patients needed higher dose, between 0.6 and 0.9 mg/kg. The mean dose for the whole patient population at the end of the study was 0.62 +/- 0.16 mg/kg. No complication nor side effect was noted. The influence of blood flow, nature of dialysis membrane, level of hematocrit was studied. In conclusion, 0.5 mg/kg of enoxaparine can prevent thrombotic manifestations in almost half of chronic hemodialysed patients with good results. Further studies could precise the place of personal or technical parameters in the choice of the optimal dose for each patient.

Study of carbohydrate material isolated from ultrafiltrates in patients with chronic renal failure.

We have isolated substances of molecular weight ranging between 350 and 2,000 daltons from ultrafiltrates of 3 patients treated by maintenance haemodialysis for chronic renal failure. Such substances might have a role in the genesis of uraemic toxicity. We have chiefly studied their carbohydrate content. Material was fractionated according to a procedure previously used to urine in healthy controls. Consecutive ion exchange, charcoal Celite and paper chromatography lead to the isolation and purification of oligosaccharides, glycopeptides, glucuronoconjugates and peptides. The different classes of carbohydrate material present in dialysis fluids from uraemic patients are close to those formed in normal urines. All the oligosaccharides in renal failure urine had have identified in normal urine. In a previous studies we have demonstrated that the levels of glucuronoconjugates are higher in the blood of uraemic patients. The glucuronoconjugates and their aglycones could have a toxic effect but a great part of them is removed by hemodialysis.

Renal transplantation and viral infections. III. Clinical and virological correlations.

Studies of the serological development after 26 renal transplants confirm the high frequency of antibody rises not only against the herpes virus group, but also against other virus groups such as measles, Coxsackie B viruses. These antibody rises correlate with febrile episodes and hepatic dysfunction in which CMV is the most often involved. However, the frequency of antibody rises against various viral antigens without any clinical event to suggest viral etiology; the lack of concomitant virus isolation (except the herpes group), as well as the ocurrence of simultaneous antibody rises against several viruses, all suggest that some of these various antibody rises observed may be related to immunological dysfunction rather than to virus infection.