Nosocomial pseudobacteremia. Positive blood cultures due to contaminated benzalkonium antiseptic
R. A. Kaslow, D. C. Mackel and G. F. Mallison
Pseudomonas cepacia or Enterobacter species or both were isolated from
blood cultures of 79 patients in a community hospital between April 1971
and March 1972. No common exposures other than venipuncture correlated with
positive blood cultures. Pseudomonas cepacia, Enterobacter, and other
Gram-negative enteric bacteria were cultured from aqueous benzalkonium
chloride used for skin antisepsis prior to ordinary and blood culture
venipuncture. Contamination of blood cultures by organisms from the
antiseptic most likely accounted for positive cultures in 35 to 38 patients
(92%) with P cepacia. The remaining three patients had repeated blood
cultures positive for P cepacia and circumstantial clinical evidence of
bacteremia; they may have contracted disease through exposure to the
contaminated antiseptic. Substitution of an iodine-alcohol antiseptic
abruptly reduced the isolation of P cepacia and Enterobacter.
