356. The Role of Procalcitonin in Antimicrobial Stewardship Among Cancer Patients Admitted with COVID-19

Abstract Background Procalcitonin (PCT) has been used to guide antimicrobial therapy in bacterial infections. With the wide spread use of empiric use of antibiotics in cancer patients admitted with COVID-19 disease, we aimed to evaluate the role of PCT in decreasing the duration of empiric antimicrobial therapy among cancer patients admitted with COVID-19. Methods We conducted a retrospective study of cancer patients admitted to MD Anderson Cancer Center who had a PCT test done within 72 hours of admission following their COVID-19 diagnosis between March 1, 2020 and June 6, 2021. Patients were divided into 2 groups of PCT < 0.25 ng/mL and PCT >=0.25 ng/mL. We assessed pertinent cultures including blood and respiratory, as well as antibacterial use and duration of empiric antibacterial therapy. Results We identified 544 patients with a median age of 62 years (range, 14-93). There were 312 (57%) patients that had at least one culture obtained from a sterile or infected site within 7 days following admission. None of the patients who had PCT< 0.25 had a positive culture whereas 41/111 (37%) patients with PCT >= 0.25 had at least one positive culture [P< 0.0001]. Among the 373 patients who had a PCT < 0.25, 129 (35%) patients received more than 72 hours of IV antibiotics compared to 87/171 (51%) among patients with PCT >=0.25 [P= 0.0003]. Conclusion These results confirm the correlation between a PCT level greater than 0.25 and a documented bacterial infection. Furthermore, procalcitonin could be useful in enhancing antimicrobial stewardship in cancer patients with COVID-19 by reducing the duration of antimicrobial therapy beyond the initial empiric 72 hours until PCT results become available. Disclosures Natalie J Dailey Garnes, MD, MPH, AlloVir (Other Financial or Material Support, collaborator on research protocol)

Background. Procalcitonin (PCT) has been used to guide antimicrobial therapy in bacterial infections. With the wide spread use of empiric use of antibiotics in cancer patients admitted with COVID-19 disease, we aimed to evaluate the role of PCT in decreasing the duration of empiric antimicrobial therapy among cancer patients admitted with COVID-19.
Methods. We conducted a retrospective study of cancer patients admitted to MD Anderson Cancer Center who had a PCT test done within 72 hours of admission following their COVID-19 diagnosis between March 1, 2020 and June 6, 2021. Patients were divided into 2 groups of PCT < 0.25 ng/mL and PCT >=0.25 ng/mL. We assessed pertinent cultures including blood and respiratory, as well as antibacterial use and duration of empiric antibacterial therapy.
Results. We identified 544 patients with a median age of 62 years (range, 14-93). There were 312 (57%) patients that had at least one culture obtained from a sterile or infected site within 7 days following admission. None of the patients who had PCT< 0.25 had a positive culture whereas 41/111 (37%) patients with PCT >= 0.25 had at least one positive culture [P< 0.0001]. Among the 373 patients who had a PCT < 0.25, 129 (35%) patients received more than 72 hours of IV antibiotics compared to 87/171 (51%) among patients with PCT >=0.25 [P= 0.0003].
Conclusion. These results confirm the correlation between a PCT level greater than 0.25 and a documented bacterial infection. Furthermore, procalcitonin could be useful in enhancing antimicrobial stewardship in cancer patients with COVID-19 by reducing the duration of antimicrobial therapy beyond the initial empiric 72 hours until PCT results become available.
Disclosures. Natalie J Dailey Garnes, MD, MPH, AlloVir (Other Financial or Material Support, collaborator on research protocol)

Session: P-15. COVID-19 Diagnostics
Background. The purpose of this study was to compare chest computed tomography (CT) scan findings in cancer versus non-cancer patients with COVID-19 infection. We sought to assess the correlation between radiologic patterns of COVID-19 pneumonia, clinical course, and outcomes.
Methods. We performed a retrospective study of COVID-19 positive cancer and non-cancer pts who had chest CT scans at the time of diagnosis, at our hospital and 16 other centers in Asia, Australia, Europe, North America and South America, between March, 2020 and November, 2020. Patients' age, underlying diseases, symptoms, laboratory studies, and radiologic findings consisting of bilateral ground-glass opacities (GGOs), multifocal organizing pneumonia (MOP) were collected in association with clinical outcomes.
Conclusion. This study reveals that non-cancer pts tended to have more radiologic findings on chest CT scan compared to cancer pts at the time of COVID-19 diagnosis and were associated with more worrisome COVID-19-related clinical outcomes. Background. Epicardial adipose tissue (EAT) is a highly inflammatory depot of fat, with high concentrations of IL-6 and macrophages, which can directly reach the myo-pericardium via the vasa vasorum or paracrine pathways. TNF-α and IL-6 diminish cardiac inotropic function, making EAT inflammation a potential cause of cardiac dysfunction.

Early Cardiac Marker of Mortality in COVID-19
Methods. A retrospective cohort study assessing EAT Thickness and Density from CT scans, without contrast, from adult patients during index admission for COVID-19 infection at Mount Sinai Medical Center from March 2020 to January 2021. A total of 1,644 patients were screened, of which 148 patients were included. Follow-up completed until death or discharge. The descriptive analysis was applied to the general population, parametric test of normality for comparisons between groups. Kaplan survival analysis was conducted after survival distribution was confirmed significant. It was followed by the assumption of normality by Q-Q Plot, prior to performing a multiple regression analysis in the vulnerable group using a K-Matrix input for cofounders. A log-rank test was conducted to determine differences in the survival distributions for the different ranges of EAT thickness.
Results. A total of 148 Participants were assigned to two groups based on epicardial adipose tissue in order to classify them as increased or decreased risk of cardiovascular risk: >5mm (n = 99), < 5mm (n = 49). The survival percentage was higher in the group with no EAT inflammation compared to the group with EAT inflammation (95.0% and 65%, respectively). Participants with EAT >5mm had a median day of hospital stay of 18 (95% CI, 16.86 to 29.92). The survival distributions for the two categories were statistically significantly different, χ2(2) = 6.9, p < 0.01. A Bonferroni correction was made with statistical significance accepted at the p < 0.025 level. There was a statistically significant difference in survival distributions for the EAT >5 mm vs EAT < 5 mm, χ2(1) =6.953, p = 0.008.