Anticoagulant-related nephropathy (ARN) is a rare but important disease and often misdiagnosed. The hallmark of the diagnosis is acute kidney injury (AKI) superimposed on preexisting kidney disease due to anticoagulation-induced glomerular hemorrhage with histologic features of widespread tubular obstruction by red blood cells and red cell casts. As ARN is a diagnosis of exclusion only proven by renal biopsy, the diagnosis is often unlikely to be confirmed histologically because of fear of biopsy-related bleeding during anticoagulant therapy. Given the large differential diagnosis in AKI, diagnosing ARN remains a challenge for clinicians. A case report and the pitfalls related to diagnosis and management will be discussed in this paper.