After a brief review about the principal risks of infection caused by the application of dialysis, the Authors describe the results relative to the control of the bacteriological contamination present in a dialysis unit of a large Roman hospital. The results showed a general compliance with the guidelines. However the older models of the apparatus were found to be more contaminated than the more up to date models and the contamination risk was higher in correspondence with connections of the apparatus. Furthermore the presence of opportunistic microrganisms such as P aeruginosa suggests the need for their substitution
