Biofilms, infection, and parenteral nutrition therapy

Parenteral nutrition therapy is used in patients with a contraindication to the use of the gastrointestinal tract, and infection is one of its frequent and severe complications. The objective of the present study was to detect the presence of biofilms and microorganisms adhering to the central venous catheters used for parenteral nutrition therapy by scanning electron microscopy. Thirty-nine central venous catheters belonging to patients with clinical signs of infection (G1) and asymptomatic patients (G2) and patients receiving central venous catheters for clinical monitoring (G3) were analyzed by semiquantitative culture and scanning electron microscopy. The central venous catheters of G1 presented more positive cultures than those of G2 and G3 (81% vs 50% and 0%, respectively). However, biofilms were observed in all catheters used and 55% of them showed structures that suggested central venous catheters colonization by microorganisms. Approximately 53% of the catheter infections evolved with systemic infection confirmed by blood culture. The authors conclude that the presence of a biofilm is frequent and is an indicator of predisposition to infection, which may even occur in patients who are still asymptomatic.