Extremely Elevated International Normalized Ratio in a Patient with Dabigatran Etexilate Use

A 76-year-old male with a past medical history (PMH) of hypertension, type 2 diabetes mellitus, chronic kidney disease (CKD) stage three, chronic nonvalvular atrial fibrillation (AF) on anticoagulation, and status post-left-sided nephrectomy in 2000 for acute pyelonephritis presented with multiple episodes of epistaxis and shortness of breath. On exam, the patient was afebrile and saturating 95% on room air. There was crusted blood present in bilateral nares along with a 6 x 3-centimeter area of ecchymosis present on the lateral aspect of the right abdominal wall. Laboratory findings revealed hemoglobin of 6.8 g/dL, hematocrit of 26.5%, bicarbonate of 20.0 mmol/L, blood urea nitrogen (BUN) of 106 mg/dL, creatinine of 3.83 mg/dL, and an INR of >10.0. The patient was initially treated with idarucizumab, which is a monoclonal antibody fragment that binds to dabigatran metabolites and in turn neutralizes dabigatran and the anticoagulant effect of its metabolites. Dabigatran was also discontinued in the setting of elevated creatinine and underlying CKD stage three. After the symptoms resolved, the patient was discharged in a stable condition. Follow-up with the primary care physician (PCP) and cardiology clinic was scheduled for further initiating anticoagulation. Dabigatran etexilate, when used in patients with renal impairment, has been associated with an increased risk of bleeding in patients. The medication is predominantly excreted by the kidneys (80%) and therefore, renal impairment patients require a reduced dose. There have been multiple reported cases of bleeding related to dabigatran use. However, to the best of our knowledge, this is the first report of an elevated INR of this extreme with the use of dabigatran.