Infections a staphylocoques coagulase-negatifs liees aux catheterismes veineux

In recent years, the incidence and severity of nosocomial infections due to coagulase negative staphylococci (CNS) dramatically increased. About 5 to 10% of venous catheterizations are responsible for clinic and/or bacteriologic sepsis, but true incidence vary from 0 to more than 30 infections per day of catheter use. Bacteria spread from the colonization of the fibrin sheath within and around the catheter tip. The potential sources and routes of colonization by CNS include skin flora at the entry site, hub during manipulations of the line and rarely hematogenous seeding after intestinal translocation (Granulocytopenia). The process of adherence, colonization and infection exist in a sequential relationship, in some way dependant on hydrophobicity and/or slime production by numerous strains of SCN. The most reliable means of confirming the diagnosis of catheter related sepsis is the (semi) quantitative culture of the catheter tip, which needs removal of the catheter. To avoid unnecessary removal, and when the catheter must be kept "in situ", (semi) quantitative blood cultures through the catheter, eventually compared with quantitative peripheral blood cultures, appear to be a safe and useful tool to diagnose catheter sepsis. Based on clinical, anamnestic and bacteriological data, the treatment lies on removal of the catheter whenever possible, replacement of catheter over a guide-wire and/or antibiotic therapy. Antibiotics should be given by the catheter kept in place, using either a systemic therapy or the "antibiotic-lock" method. For prevention, primary importance must be attached to frequent handwashing, meticulous aseptic techniques and strict attention to protocols. Progress will be the fruits of a better understanding of host defense mechanisms in the vicinity of catheters, of the conception of new bio compatible and antiadhesive surfaces and/or optimal local conditions that will not permit colonization by highly virulent strains of some microorganisms, especially coagulase negative staphylococci.