Infection assessment of totally implanted long-term venous access devices

Comparison of catheter tip versus port content culture techniques to assess infection in totally implanted vascular access devices (TIVAD).

Comparison of pocket swab, catheter-tip and port content cultures after removing the silicon puncture septum in a prospectively collected consecutive series of 102 TIVAD removed for clinical suspicion of infection, between May 2000 and March 2003.

102 totally implanted port-catheters in 98 patients, age ranging from 1 to 90 years (median 53 years), were removed 7 to 2616 days after insertion (median 210 days). Infection of the pocket surrounding the port was found in 21 cases, all proven by a positive culture of the pocket swab. Out of the remaining 81 cases without pocket infection, 32 had only a positive catheter tip culture, whereas 56 had a positive port content culture (p = 0.0002). Always the same microorganism was isolated in the 32 patients with positive catheter tip and port content cultures. The main organisms identified within TIVAD were Coagulase Negative Staphylococcus (CNS) (41 cases) and Candida sp (15 cases). Eight out of the 21 pocket infections were caused by Staphylococcus aureus.

In the presence of local signs of infection, taking cultures of the pocket surrounding the port is sufficient for diagnostic purposes. When infection is localized within the device only, port content cultures taken after removal of the silicon septum are more often positive than cultures of the catheter tip, and constitute therefore a more reliable tool for the assessment of TIVAD infection.