Via practica 1/2020

Anticoagulation-related nephropathy

Anticoagulant (AC) overdose may lead to nephropathy, characterized by acute renal impairment (AKI) due to marked intraglomerular haemorrhages with erythrocyte tubule obstruction and clinical manifestations include hematuria. Anticoagulation-related nephropathy (ARN) accompanies treatment with vitamin K antagonists (VKA) as well as novel oral anticogulants (NOAC). It is a serious, underdiagnosed, clinical complication accompanying AC treatment that increases mortality and morbidity. Significantly reduces 1-year (68.9 % with ARN vs 81.1 % without ARN; p = 0.049) as well as 5-year survival (58 % with ARN vs 73 % without ARN, p < 0.001) in patients with higher INRs (International Normalized Ratio) > 3. It is also a risk factor for the development and progression of chronic kidney disease (CKD). ARN episodes occur in up to 20.5 % of patients treated with warfarin. Risk factors for the development of ARN include previous CKD, age, arterial hypertension, diabetic nephropathy, glomerulonephritis, and heart failure. Chronic renal disease is the most important risk factor for the development of ARN (33 – 37 % vs 16.5 % in patients without CKD), as higher INR values can be achieved at lower doses of warfarin due to non-renal clearance. AKI without any other known renal aetiology, presence of macroscopic or microscopic HU, which may, however, also be absent and increased INR. The basis of ARN therapy is discontinuation of AC therapy with normalization of hemocoagulation parameters (INR), thereby affecting glomerular bleeding and kidney damage and administration of N-acetylcystein using its antioxidant effect to prevent the development of AKI.

Keywords: anticoagulant treatment, anticoagulant-related nephropathy, chronic kidney disease, INR