Rapid diagnostics have been demonstrated to be a crucial component of antimicrobial stewardship programs. However, most of the studies have been conducted in developed countries where health-care facilities have 24/7 microbiology laboratories. Colombia is an example of a developing country with limited resources in which hospitals are not able to implement a 24/7 model and samples are usually processed once a day. Here, we compared time to pathogen identification by QuickFISH® with conventional cultures and its effect on decrease duration of therapy in critical patients.
A multicenter, ambispective cohort study was conducted in four high-complexity ICU hospitals between 2016-2017. Adult patients admitted to the ICU with positive blood cultures and signs of systemic inflammatory response syndrome were included in the study. Patients with bloodstream infections identified by either QuickFISH® or PNA FISH® were observed prospectively and compared with those patients with bloodstream infections identified by conventional blood cultures alone who were analyzed retrospectively. Duration of treatment, time to final reports and survival rate were compared between the two groups. Additionally, the performance of the molecular test was compared with the conventional blood culture.
A total of 153 patients were included in the study. Among them, 72 (47%) were in the QuickFISH® / PNA FISH® group and 81 (53%) in the conventional blood culture group. 87% of the patients had a bacteria identified (n=133) and 13% (n=20) a candida. QuickFISH® / PNA FISH® had 96% (89%-100%) concordance with blood culture. The microbiological identification report was 26 hours faster in the QuickFISH® group than in blood culture group (29 hours vs. 55 hours; p = 0.0001). The duration of antimicrobial therapy was 3.2 days shorter in the QuickFISH® group compared to the BC group (13.7 days vs. 16.9 days; p = 0.026).
Molecular diagnostic methods such as QuickFISH® reduce the time to final reports as well as the duration of therapy in ICU patients with bloodstream infections. Despite having more impact in 24/7 laboratories, QuickFISH® methods may be a promising diagnostic tool in developing countries if incorporated with antimicrobial stewardship programs.