The following is a summary of “Monocyte Distribution Width as a Diagnostic Marker for Infection: A Systematic Review and Meta-analysis,” published in the July 2023 issue of the Chest by Malinovska et al.
The monocyte distribution width (MDW) is an emerging infection biomarker. It is readily available as part of the routine CBC count administered upon hospital admission. The increasing availability and promising results of MDW as a sepsis biomarker have prompted its application to other infectious diseases. How effective is MDW in diagnosing multiple infectious disease outcomes and care settings? By searching PubMed, Embase, Scopus, and Web of Science through February 4, 2022, a systematic review of the diagnostic performance of MDW for multiple infectious disease outcomes was conducted.
A meta-analysis was conducted on products with at least three identified reports (sepsis and COVID-19). Individual diagnostic performance measures were calculated using linear mixed-effects models to generate pooled estimates. Researchers found 29 studies that met the inclusion criteria. Most investigations focused on sepsis (19) and COVID-19 (six). Pooled estimates of diagnostic performance for sepsis varied by reference standard (Second versus Third International Consensus Definitions for Sepsis and Septic Shock criteria) and tube anticoagulant used, ranging from an area under the receiver operating characteristic curve (AUC) of 0.74 to 0.94, with a mean sensitivity of 0.69 to 0.79 and a mean specificity of 0.57 to 0.80.
The pooled AUC of MDW for COVID-19 was 0.76, the mean sensitivity was 0.79, and the mean specificity was 0.59. MDW demonstrated excellent diagnostic efficacy for both sepsis and COVID-19. Diagnostic thresholds for sepsis should be selected with the reference standard and tube type in mind.