Plasma urea / creatinine ratio of 20:1 may be seen in-: (A) Rhabdomyolysis, (B) Ureteric calculi, (C) Pre-renal failure, (D) Chronic glomerulonephritis
Answer is C. Background. A blood urea nitrogen (BUN)/creatinine ratio (BCR) >20 (0.081 in international unit) is used to distinguish pre-renal azotemia (PRA) and acute tubular necrosis (ATN). However, there is little evidence that BCR can distinguish between these two conditions and/or is clinically useful Ref Harrison20th edition pg 299