A patient with anemia is found to have a low serum erythropoietin level and a high serum creatinine level. What is the most likely underlying cause of their anemia?

A Iron deficiency anemia
B Vitamin B12 deficiency anemia
C Anemia of chronic kidney disease
D Sickle cell anemia
The combination of low serum erythropoietin and high serum creatinine suggests anemia of chronic kidney disease, as the kidneys are responsible for producing erythropoietin.
National Kidney Foundation Guidelines
Hematology Hematology: Anemia Hematology: Anemia Medium MEDICAL Confidence: high