December 22, 2021
Fungus Among Us? Mortality Prognostication Using (1→3)-β-D-glucanBy Nirav Patel, MD
As a highly specific marker of fungal infection, many clinicians use (1→3)-β-D-glucan (BDG) levels to help identify these potentially occult infections, especially when cultures may not be possible or require prolonged incubation. A sub-analysis of data collected as part of the INTENSE study and reported in Clinical Infectious Diseases has suggested another possible use for BDG.
Using a threshold of > 100 pg/mL, investigators noted an increased Sequential Organ Failure Assessment score (2 for < 100 pg/mL vs. 5 for > 100 pg/mL; P < .0001) and an increased mortality (13.7% vs. 39%, P = .0002). Mortality was elevated in patients with invasive candidiasis and BDG > 100 pg/mL at 42% but also elevated in patients without diagnosis of invasive candidiasis but elevated BDG at 37%, compared to 25% for patients who did not have elevated BDG levels nor invasive candidiasis. The INTENSE study did not demonstrate benefit of administration of micafungin, and benefit was not shown in this sub-study either.
There are several pathophysiologic considerations as to why elevations in BDG (especially without evidence of active infection) could impact outcomes, though the clinical association may be helpful in managing critically ill patients. Furthermore, intervention with micafungin did not impact outcome, suggesting a much more complex series of interactions within the host beyond a simplistic understanding: onset of infection, leading to an inflammatory response, leading to organism and host effects. Clearly much more investigation is needed to elucidate these processes that may lead to other opportunities to intervene to improve outcomes.
