- RED CELL CASTS means renal hematuria, always pathologic
- Causes: acute glomerulonephritis, lupus nephritis, Goodpastures, SBE, renal trauma,renal infarction, severe pyelonephritis, RCHF, renal vein thrombosis
- may appear brown or colorless, may contain only a few RBC’s, RBC casts can degenerate to hemoglobin or blood cast, brown-red in color