Impact of the beta-glucan test on management of intensive care unit patients at risk of invasive candidiasis.

Background: The 1,3-beta-D-glucan (BDG) test is used for diagnosis of invasive candidiasis (IC) in intensive care units (ICU). However, its utility for patients9 management is unclear. This study assessed the impact of BDG results on therapeutic decisions. Methods: This was a single-center observational study conducted in ICU over two 6-month periods. All BDG requests for detection of IC were analyzed. Before the second period, the ICU physicians received a pocket card instruction (algorithm) for targeted BDG testing in high-risk patients. BDG performance for IC diagnosis was assessed, as well as its impact on antifungal (AF) prescription. Results: Overall, 72 patients had ≥1 BDG test and 14 (19%) had IC diagnosis. BDG results influenced therapeutic decisions in 41 (57%) cases. The impact of BDG was positive in 30 (73%) of them: AF abstention/interruption following a negative BDG (N=27), AF initiation/continuation triggered by positive BDG and subsequently confirmed IC (N=3). In 10 (24%) cases, a positive BDG resulted in AF initiation/continuation with no further evidence of IC. Negative BDG and AF abstention with subsequent IC diagnosis was observed in one case. The positive predictive value (PPV) of BDG was improved if testing was restricted to the algorithm9s indications (80% vs 36%). However, adherence to the algorithm was low (26%) and no benefit of the intervention was observed. Conclusion: BDG had an impact on therapeutic decisions in more than half cases, which consisted mainly of safe AF interruption/abstention. Targeted BDG testing in high-risk patients improves PPV, but is difficult to achieve in ICU.