Tigecycline-Associated Hypofibrinogenemia and Major Bleeding: Incidence, Predictors, and Clinical Outcomes in a Retrospective Cohort.

Background: Tigecycline-associated hypofibrinogenemia has been increasingly reported, but its clinical significance and predictors of bleeding remain unclear. We assessed incidence, predictors, and bleeding outcomes in routine care. Methods: We conducted a retrospective cohort study of adults receiving tigecycline at a tertiary medical center in 2022. Hypofibrinogenemia was defined as fibrinogen less than 200 mg/dL during treatment. Major bleeding was defined using International Society on Thrombosis and Haemostasis criteria. Patients were followed from treatment initiation until 7 days after discontinuation. Multivariable logistic regression identified independent predictors of hypofibrinogenemia and major bleeding. Receiver operating characteristic analyses determined optimal cut-offs using the Youden index. Results: Among 231 included patients, 98 (42.4%) developed hypofibrinogenemia. Major bleeding occurred in 52 (22.5%) patients and was more frequent in patients with hypofibrinogenemia (30.6% vs 16.5%, p = 0.01). Independent predictors of hypofibrinogenemia included baseline fibrinogen less than 350 mg/dL (aOR: 3.27, 95% CI: 1.73-6.19), hemodialysis (aOR: 2.34, 95% CI: 1.02-5.38), peptic ulcer disease (aOR: 7.10, 95% CI: 1.38-38.53), and cumulative tigecycline dose greater than 1125 mg (aOR: 2.60, 95% CI: 1.40-4.84). Hypofibrinogenemia was the only independent predictor of major bleeding (aOR: 2.25, 95% CI: 1.14-4.44). Conclusion: Hypofibrinogenemia was common during tigecycline therapy and independently associated with major bleeding. Baseline fibrinogen and cumulative exposure may help identify high-risk patients. Routine fibrinogen monitoring should be considered during tigecycline treatment.