Criteria of Brodsky et al for Warfarin-Related Nephropathy (Anticoagulation-Related Nephropathy)

The patient may present with unexplained hematuria and/or a rise in serum creatinine.

Clinical criteria:

(1) current therapy with an anticoagulant

(2) INR > 3.0

(3) elevated serum creatinine (increase >=0.3 mg/dL)

(4) exclusion of other causes

Pathologic features:

(1) dysmorphic red blood cells in the glomerulus seen on electron microscopy (EM)

(2) hemorrhage throughout the specimen (hemorrhage limited to the edges could be biopsy artifact)

(3) absence of other explanations for hemorrhage (active glomerulonephritis, interstitial nephritis etc)