INTRODUCTION:The most severe complication of parenteral nutrition (PTN) is catheter-related infection (CRI). OBJECTIVES:To study the incidence rate and factors associated to CRI. MATERIAL AND METHODS:271 patients followed at the Nutrition Unit for 6 months. The composition of the PTN was calculated according to the metabolic demands. 20.3% received a lipid solution enriched with omega-3 fatty acids (SMOF Fresenius Kabi®) and 79.7% with olive oil (Clinoleic Baxter®). RESULTS:The rate of CRI was 25 per 1,000 days of PTN (55 patients: 61.7±17.8 years, 60.3% males, 29.3±10.6 days of hospital stay and 10.4% mortality). Coagulase-negative Staphylococcus was the most frequently isolated microorganism. There were no differences by age, gender, mortality, or composition of the PTN between patients with or without infection. The patients treated with omega-3 received more calories with the PTN, at the expense of higher intake of glucose and lipids. However, the rate of infection was similar, although there was a not significant trend towards a lower infection rate when using the omega-3 composition (14.5% vs. 23.1%, respectively, p = 0.112). The duration of the nutritional support was higher in patients with CRI (13.0 ± 9.7 vs. 9.3 ± 8.1, p = 0.038). Total mortality (16.9%) was independent of the presence or absence of CRI (10.4% vs. 18.7%, p = 0.090) or of the use of omega-3 lipids or olive oil in the PTN (10.9% vs. 18.5%, p = 0.125). CONCLUSION:Patients submitted to PTN have a high rate of CRI. The presence of infection is related to the duration of the PTN, being independent of the age, gender, and composition of the solution. The use of omega-3 lipid solutions may be beneficial although further studies are needed to confirm this.