[Nosocomial urinary infections].

The concept of nosocomial urinary tract infection now corresponds to a precise definition. It is generally related to bladder catheterization, constitutes the most frequent form of nosocomial infection (30 to 50% of infections), and represents the third most frequent portal of entry of bacteraemia. The organism most frequently isolated is Escherichia coli; but the flora is changing and the ecological distribution is continually modified. Despite their usually benign nature, these nosocomial infections can nevertheless influence hospital mortality; they increase the hospital stay by an average of 2.5 days and their treatment represents a large share of the antibiotic budget. Prevention of these infections is therefore essential, with particular emphasis on simple and universally accessible measures: very precise indications for vesical catheterization, use of closed circuit drainage, maximal asepsis when handling catheters, after washing the hands.