Red blood cell (RBC) casts may point to glomerulonephritis ... The presence of muddy brown granular casts in acute kidney injury (AKI) supports a diagnosis of ATN, while a near-normal urinalysis ...

Secondly, no validated 'gold standard' exists for discriminating between PRA and ATN (except for kidney biopsy ... of renal tubular epithelial cells and granular casts (that is, a score of ...