In this single-center, retrospective cohort analysis of hospitalized coronavirus disease 2019 (COVID-19) patients, we investigate whether inflammatory biomarker levels predict respiratory decline in patients who initially present with stable disease. Examination of C-reactive protein (CRP) trends reveals that a rapid rise in CRP levels precedes respiratory deterioration and intubation, although CRP levels plateau in patients who remain stable. Increasing CRP during the first 48 h of hospitalization is a better predictor (with higher sensitivity) of respiratory decline than initial CRP levels or ROX indices (a physiological score of respiratory function). CRP, the proinflammatory cytokine interleukin-6 (IL-6), and physiological measures of hypoxemic respiratory failure are correlated, which suggests a mechanistic link. Our work shows that rising CRP predicts subsequent respiratory deterioration in COVID-19 and may suggest mechanistic insight and a potential role for targeted immunomodulation in a subset of patients early during hospitalization.

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BACKGROUND: Bebtelovimab is a monoclonal antibody used to prevent progression of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Complications of SARS-CoV-2 infection can include cardiac effects including sinus bradycardia. CASE SUMMARY: We describe the case of an 86-year-old male infected with SARS-CoV-2 who experienced bradycardia with cardiac arrest immediately following infusion of Bebtelovimab with return of spontaneous circulation obtained following 1 minute of chest compressions and administration of atropine. His bradycardia resolved, and he was extubated on hospital day 1, found to be neurologically intact, and discharged on hospital day 9. CONCLUSIONS: Due to the time course of the patient’s symptomatology, we attribute the bradycardic arrest to the Bebtelovimab infusion. This case illustrates the need for further research into the etiology of bradycardia due to SARS-CoV-2 infection and to examine potential links to monoclonal antibody infusion. It also serves as important caution to maintain close cardiac monitoring while administering monoclonal antibodies for SARS-CoV-2.