What is the difference between RIFLE & KDIGO criteria in differentiating a tubular injury?

Ans. C. Urinary NGALRIFLE originally used urinary sodium, urine osmolarity, FeNa to define tubular dysfunction/injury.Currently urinary NGAL/Kim-1/Cystatin C/L-FABP all are being evaluated as more sensitive and specific markers of tubular injury (KDIGO 2017/18).