|Establishment of an in vitro model system for the study of biofilm formation in Hemodialysis tunneled catheters
|This project aims to better understand infections related to Hemodialysis (HD) catheters and to improve their prevention and treatment. In Portugal this is particularly relevant since our country has a higher incidence and prevalence of end stage-renal disease (ESRD) compared to most of other European countries. However, the outputs of the project can have world-wide implications. Hemodialysis is the most widely renal replacement therapy (RRT) used for patients with ESRD. A major complication of this technique is the infection-related morbidity and mortality due to bacteremia. In particular, the use of tunnelled cuffed catheters (TCC) is associated with a substantially greater risk of sepsis, hospitalization and mortality compared to the use of an arteriovenous fistula (AVF). In our country, a TCC is used for the initial dialysis session in more than 50% of incident HD patients and ~20% of prevalent HD patients. It is known that biofilm formation occurs within 24 hours of catheter insertion, however the HD catheter is different from others used for intravenous delivery because the rate of blood flow through its lumen is extremely high. These facts demonstrate the critical importance of research on the biology of both TCC infection development and avoidance. Previous studies have relied strictly on in vitro models to study biofilm formation, but in order to reproduce the conditions observed in HD-catheter infections one needs to capture the characteristic parameters which mimic the in vivo environment in a cultivation system. Parameters include medium composition, fluid flow conditions, catheter-material analysis and isolation of the microbiota prevalent on HD-catheter biofilms.
Biofilm development in TCC is often an underestimated problem. Thus, to improve the current knowledge the relationship between biofilm formation and TCC-related infections, this project focuses on two main research lines: 1) evaluation of clinical isolates from TCCs removed from HD pat
|Maria Pia Ferraz