The most frequent complications of long term TCVC are catheter related blood steam infections(CRBSI)often caused by microorganisms located in the biofilm formed on the inner surface of the TCVC after a short time. CRBSI may be lifethreatening, will need long term intravenous broad spectrum antibiotic therapy possibly combined with intraluminal antibiotic lock therapy. In spite of this CRBSI may often lead to the premature removal of the TCVC.