Which statement about anemia in chronic kidney disease is accurate?

• A. Iron deficiency is the sole cause of anemia in CKD.
• B. Anemia in CKD stems from decreased erythropoietin production by the kidneys.
• C. CKD does not affect red blood cell production.
• D. Polycythemia is common in CKD.

Answer: (B)

The main idea is that anemia in chronic kidney disease is driven primarily by reduced erythropoietin production by the kidneys. Erythropoietin is the hormone that signals the bone marrow to produce red blood cells. In CKD, damaged kidneys make less erythropoietin, so the marrow isn’t adequately stimulated to keep up with red cell production, leading to anemia that is typically normocytic and normochromic. Iron deficiency or inflammation can worsen anemia in CKD, but they are not the sole cause; without enough erythropoietin, the marrow can’t produce enough red cells regardless of iron status. CKD also tends to shorten red blood cell lifespan and can impair iron utilization, reinforcing the deficit. Polycythemia is not a common feature of CKD, so that option doesn’t fit the usual pattern.