Bacteremic complications of intravascular catheter tip colonization with Gram-negative micro-organisms in patients without preceding bacteremia

Abstract

Although Gram-negative micro-organisms are frequently associated with catheter-related bloodstream infections, the prognostic value and clinical implication of a positive catheter tip culture with Gram-negative micro-organisms without preceding bacteremia remains unclear. We determined the outcomes of patients with intravascular catheters colonized with these micro-organisms, without preceding positive blood cultures, and identified risk factors for the development of subsequent Gram-negative bacteremia. All patients with positive intravascular catheter tip cultures with Gram-negative micro-organisms at the University Medical Center, Utrecht, The Netherlands, between 2005 and 2009, were retrospectively studied. Patients with Gram-negative bacteremia within 48 h before catheter removal were excluded. The main outcome measure was bacteremia with Gram-negative micro-organisms. Other endpoints were length of the hospital stay, in-hospital mortality, secondary complications of Gram-negative bacteremia, and duration of intensive care admission. A total of 280 catheters from 248 patients were colonized with Gram-negative micro-organisms. Sixty-seven cases were excluded because of preceding positive blood cultures, leaving 213 catheter tips from 181 patients for analysis. In 40 (19%) cases, subsequent Gram-negative bacteremia developed. In multivariate analysis, arterial catheters were independently associated with subsequent Gram-negative bacteremia (odds ratio [OR] = 5.00, 95% confidence interval [CI]: 1.20–20.92), as was selective decontamination of the digestive tract (SDD) (OR = 2.47, 95% CI: 1.07–5.69). Gram-negative bacteremia in patients who received SDD was predominantly caused by cefotaxime (part of the SDD)-resistant organisms. Mortality was significantly higher in the group with subsequent Gram-negative bacteremia (35% versus 20%, OR = 2.12, 95% CI: 1.00–4.49). Patients with a catheter tip colonized with Gram-negative micro-organisms had a high chance of subsequent Gram-negative bacteremia from any cause. This may be clinically relevant, as starting antibiotic treatment pre-emptively in high-risk patients with Gram-negative micro-organisms cultured from arterial intravenous catheters may be beneficial.

Low incidence of subsequent bacteraemia or fungaemia after removal of a colonized intravascular catheter tip

“…Some studies have shown that the incidence of bacteraemia was low after removal of IVCs in patients where that tip culture became positive [2,5]. Other authors have postulated that positive tip cultures, in particular those with S. aureus [1,6,7], Candida spp [4], and Gram-negative bacteria [8] with negative concurrent blood cultures, could reflect a recent bloodstream infection, and therefore require a short course of antimicrobial therapy, or point to the potential risk of developing delayed bacteraemia (or fungaemia).…”

Investigation of biofilm formation on a charged intravenous catheter relative to that on a similar but uncharged catheter

“…Intravascular catheters are a major source of bloodstream infections in hospitalized patients. The prevalence of catheter-related infections is approximately five episodes per 1,000 catheter days in Europe 16 and one to six episodes per 1,000 catheter days in the United States. 1 These infections often result in increased morbidity and mortality and increase costs considerably.…”

Expert consensus-based clinical practice guidelines management of intravascular catheters in the intensive care unit

“…Three retrospective [136,182,186] and two prospective observational studies [187,188] on bacterial colonisation recommended a duration of at least 3 days of antibiotic therapy, with at least one of the antibiotics adapted to antibiotic susceptibility testing. Three out of five studies, including two prospective studies, each targeting a particular microorganism, P. aeruginosa and A. baumannii, showed a marked reduction of bacteraemia rates.…”