This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Medicine
What is the difference between RIFLE & KDIGO criteria in differentiating a tubular injury? 
Select and explain. 
A. Uosm, B. Urinary Na, C. Urinary NGAL, D. FeNa (UN, x Scr / SNa x Ucr)
C: Urinary NGAL
Answer: C: Urinary NGAL 
Explanation: 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).