Diagnostic Utility of a Ferritin-to-Procalcitonin Ratio to Differentiate Patients With COVID-19 From Those With Bacterial Pneumonia: A Multicenter Study.

Abstract

BACKGROUND:

There is an urgent need for accurate, rapid, inexpensive biomarkers that can differentiate coronavirus disease 2019 (COVID-19) from bacterial pneumonia. We assess the role of the ferritin-to-procalcitonin (F/P) ratio to classify pneumonia cases into those due to COVID-19 vs those due to bacterial pathogens.

METHODS:

This multicenter case-control study compared patients with COVID-19 with those with bacterial pneumonia, admitted between March 1 and May 31, 2020. Patients with COVID-19 and bacterial pneumonia co-infection were excluded. The F/P in patients with COVID-19 vs with bacterial pneumonia were compared. Receiver operating characteristic curve analysis determined the sensitivity and specificity of various cutoff F/P values for COVID-19 vs bacterial pneumonia.

RESULTS:

A total of 242 COVID-19 pneumonia cases and 34 bacterial pneumonia controls were included. Patients with COVID-19 pneumonia had a lower mean age (57.1 vs 64.4 years; P = .02) and a higher body mass index (30.74 vs 27.15 kg/m2; P = .02) compared with patients with bacterial pneumonia. Cases and controls had a similar proportion of women (47% vs 53%; P = .5), and COVID-19 patients had a higher prevalence of diabetes mellitus (32.6% vs 12%; P = .01). The median F/P was significantly higher in patients with COVID-19 (4037.5) compared with the F/P in bacterial pneumonia (802; P < .001). An F/P ≥877, used to diagnose COVID-19, resulted in a sensitivity of 85% and a specificity of 56%, with a positive predictive value of 93.2% and a likelihood ratio of 1.92. In multivariable analyses, an F/P ≥877 was associated with greater odds of identifying a COVID-19 case (odds ratio, 11.27; 95% CI, 4-31.2; P < .001).

CONCLUSIONS:

An F/P ≥877 increases the likelihood of COVID-19 pneumonia compared with bacterial pneumonia.

• Authors: Amal A Gharamti, Fei Mei, Katherine C Jankousky, Jin Huang, Peter Hyson, Daniel B Chastain, Jiawei Fan, Sharmon Osae, Wayne W Zhang, José G Montoya, Kristine M Erlandson, Sias J Scherger, Carlos Franco-Paredes, Andrés F Henao-Martínez, Leland Shapiro
• Journal: Open forum infectious diseases (Open Forum Infect Dis) Vol. 8 Issue 6 Pg. ofab124 (Jun 2021) ISSN: 2328-8957 [Print] United States
• PMID: 34183978 (Publication Type: Journal Article)
• Copyright: © The Author(s) 2021. Published by Oxford University Press on behalf of Infectious Diseases Society of America.