Impact of the BACTEC NR system in detecting Candida fungemia

As a result of the growing importance of candidemia, various techniques for the detection of Candida spp. in blood have been designed with a view to speeding up the laboratory procedure. We have performed a retrospective comparison of the efficiencies of the conventional VACUTAINER system (Becton Dickinson Vacutainer Systems) and the BACTEC NR system (Johnston Laboratories, Inc.). During a 4-year period, 88,300 blood cultures were processed, with growth of Candida species in 552. The mean times required for the detection of growth were 7.55 days with the VACUTAINER system and 4.1 days with the BACTEC NR system (P less than 0.05). During the first week of incubation, the VACUTAINER system detected 56.1% of the candidemias and the BACTEC NR detected 93.6% (P less than 0.05). Use of the BACTEC NR therefore permits reduction of the incubation period from the previously established 4 weeks to a more convenient 7 to 14 days.