Supplementary Material for: Safety of Tigecycline in Patients on Antithrombotic Therapy: A Single Center Retrospective Study

Introduction: To investigate the risk factors of tigecycline-induced hypofibrinogenemia, and to evaluate the safety of tigecycline with concomitant antithrombotic drugs. Methods: We performed a retrospective analysis of patients who received tigecycline for more than 3 days between January 2015 and June 2019. Clinical and laboratory data were collected including fibrinogen concertation, tigecycline dose, duration of treatment, disease severity, complete blood count, indicators of infection, liver and renal function. Risk factors of hypofibrinogenemia were analyzed by univariate and multivariate analysis. To evaluate the safety of tigecycline and concomitant antithrombotic drugs, bleeding events were assessed by comparing the decline in hemoglobin and the amount of red blood cell transfusion in patients with antithrombotic drugs and those without. Results: This study included a total of 68 cases, 20 of which experienced hypofibrinogenemia while receiving tigecycline treatment. Duration of treatment, cefoperazone/sulbactam combination therapy, and fibrinogen levels prior to initiation of tigecycline were risk factors associated with tigecycline-induced hypofibrinogenemia. There were 26 recorded bleeding incidents, 25 of which happened before the start of tigecycline. Antithrombotic and non-antithrombotic patients did not differ in their hemoglobin decline or need for red blood cell transfusions while taking tigecycline. Conclusion: A longer treatment duration, cefoperazone/sulbactam combination therapy, and a lower level of fibrinogen level before tigecycline were associated with an increased risk of tigecycline induced hypofibrinogenemia. A combination of antithrombotic drugs and tigecycline did not aggravate the bleeding events during tigecycline treatment.