Development of subsequent bloodstream infection in patients with positive Hickman catheter blood cultures and negative peripheral blood cultures

There are limited data on the incidence of subsequent bloodstream infection (BSI) and the effect of systemic antibiotics in patients who had positive catheter-drawn blood cultures (CBC) and negative peripheral blood cultures (PBC). We retrospectively reviewed all paired blood cultures from patients with Hickman catheter in the hematology-oncology ward between January 1997 and December 2008. There were 112 episodes with positive CBC and negative PBC. Nine episodes (8.0%; 95% CI, 3.0-13.1%) led to subsequent BSI within 28 days. Subsequent BSI developed in 6 of 31 episodes (19%) where empiric antibiotics were inappropriate but in 3 of 81 episodes (4%) where empiric antibiotics were appropriate (P = 0.01). Subsequent candidemia (50%, 2 of 4) was more common than subsequent bacteremia (6%, 7 of 108) (P = 0.03). In conclusion, for patients with positive CBC and negative PBC, the overall incidence of subsequent BSI was 8.0%, and inappropriate empiric antibiotics was associated with subsequent BSI.