This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Haematology, Subject name: Anatomy
Anemia in chronic renal failure is due to 
Select and explain. 
A. Decreased erythropoietin production, B. Iron deficiency, C. Hypoplastic bone marrow, D. Decreased folate levels
A: Decreased erythropoietin production
Answer: A: Decreased erythropoietin production 
Explanation: Ref Harrison 19 th ed pg 630 The anemia is primarily due to a failure of EPO production by the diseased kidney and a reduction in red cell survival. In ceain forms of acute renal failure, the correlation between the anemia and renal function is weaker. Patients with the hemolytic-uremic syndrome increase eryth- ropoiesis in response to the hemolysis, despite renal failure requiring dialysis.