Dabigatran-induced anticoagulant-related nephropathy with undiagnosed IgA nephropathy in a patient with normal baseline renal function

Occasionally, over-anticoagulation with warfarin induces acute kidney injury (AKI) characterized by glomerular hemorrhage with tubular obstruction by red blood cell casts, which is widely acknowledged as warfarin-related nephropathy. Owing to extensive use of direct oral anticoagulants, similar AKI cases have been reported among patients treated with dabigatran. Dabigatran is primarily excreted by the kidneys; thus, renal impairment is one of the risk factors for dabigatran-induced bleeding complications. Nevertheless, risk factors for dabigatran-induced anticoagulant-related nephropathy (ARN) remain partially clarified. Here, we report a histologically established case of dabigatran-induced ARN with undiagnosed IgA nephropathy in a patient with normal baseline renal function. In addition, we summarize previously published cases of biopsy-proven, dabigatran-related ARN. A 67-year-old female with normal preexisting renal function developed macrohematuria and AKI. She had been treated with dabigatran for deep vein thrombosis. A renal biopsy diagnosed ARN with inactive IgA nephropathy. After dabigatran withdrawal, her macrohematuria and renal function improved. This report demonstrates that ARN could occur in patients with normal baseline renal function. Our case and prior reports suggest that IgA nephropathy could be a risk factor for dabigatran-induced ARN.