This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Kidney, Subject name: Medicine
ACE inhibitors are contraindicated in all except? 
Select and explain. 
A. Bilateral Renal artery stenosis, B. Chronic renal failure, C. Pregnancy, D. Hyperkalemia
B: Chronic renal failure
Answer: B: Chronic renal failure 
Explanation: Ans. (b) Chronic Renal FailureRef.: Harrison 19th ed. /1816ACE inhibitors and ARBs inhibit the angiotensin-induced vasoconstriction of the efferent arterioles of the glomerular microcirculation. This inhibition leads to a reduction in both intra-glomerular filtration pressure and proteinuria.* Adverse effects from these agents include cough and angioedema with inhibitors, anaphylaxis, and hyperkalemia.* The most common cause of chronic renal failure is diabetic nephropathy and is benefitted by above mentioned effects of ACE inhibitors.* Choice A bilateral renal artery stenosis leads to hyperkalemia and hence is a contraindication. Choice D is ruled out henceforth.* Choice C pregnancy, the use of ACE inhibitors has been shown to cause teratogenicity