Staphylococcus aureus catheter-associated bacteremia. Minimal effective therapy and unusual infectious complications associated with arterial sheath catheters.

OBJECTIVE: To determine factors that predict complications and examine outcomes of Staphylococcus aureus bacteremia according to the duration of antibiotic therapy.
METHODS: Clinical data were extracted from charts of patients with positive blood cultures for S aureus at a single institution during a 2-year period.
RESULTS: Of 102 patients with S aureus bacteremia, 55 were considered to have bacteremia attributable to an intravascular catheter, including five patients who were bacteremic after percutaneous transluminal coronary angioplasty. Among the other 50 patients with S aureus catheter-associated bacteremia, infection was community acquired in 18 and nosocomial in 32. Septic pulmonary emboli were more common in patients with community-acquired S aureus catheter-associated bacteremia, most of whom had Hickman catheters or venous access disks. Delayed removal of the infected catheter was associated with persistence of bacteremia (P = .01). With patients with early complications excluded, patients treated for 10 to 15 days had clinical characteristics similar to those of patients treated with longer courses of antibiotics and had similarly low rates of relapse (0% vs 4.7%). In contrast, treatment with parenteral antibiotics for less than 10 days appeared to be inadequate in that relapse occurred in two of three such patients. Staphylococcus aureus catheter-associated bacteremia associated with percutaneous transluminal coronary angioplasty was complicated by a femoral artery mycotic aneurysm in two of five patients.
CONCLUSION: Approximately one third of S aureus catheter-related bacteremias were community acquired, reflecting increased usage of intravascular devices for home parenteral support. A 10- to 15-day course of parenteral antibiotics was equivalent to longer courses of therapy in patients without early complications.