Prospectively since 11/1997, all central venous catheter related bacteremias in our dialysis center (n = 60) was recorded. We systematically tested antibiotic lock technique using pure heparin (1 ml = 5000 Ul) mixed with antibiotic matched to isolated micro-organism after 15 days of systemic antibiotherapy. During 39 months of study, 27 bacteremias were documented from 23 patients. Seventeen locks in 15 patients were performed after each dialysis sessions during one month. Associated tunnel infection did not allow to stop the lock in 3 cases. In the 12 remaining patients, we observed 4 recurrences for 3 patients after the stop of the lock with the same micro-organism in 3 times/4 without modifications of antibiotics sensibility. No septic metastases were notified and the patency of all catheters were respected. The incidence of bacteremias was 4.6 per 1000 catheters days before the lock and 0.88 after, during a mean observation period of 15 months per patients. Sterilisation of infected catheters seems possible and the incidence of bacteremias is reduce by the lock technique without coming out of septic complications or selected micro-organisms.