A client with pernicious anemia takes supplemental folate and self administers monthly vitamin B2 injections. The client reports feeling increasingly fatigued. Which laboratory value should the nurse review?

A. Serum electrolytes: Electrolytes such as sodium, potassium, and chloride are important for fluid and acid-base balance, but they are not directly related to the evaluation of anemia or the effectiveness of vitamin B12 therapy. Reviewing electrolytes would not provide specific information about the client’s fatigue caused by hematologic deficiencies. B. Complete blood count: A complete blood count (CBC) is the most relevant laboratory test for assessing anemia, including pernicious anemia. The CBC provides hemoglobin, hematocrit, red blood cell indices, and morphology, allowing the nurse to determine whether the client’s fatigue is due to inadequate red blood cell production or persistent macrocytic anemia despite supplementation. This is essential to evaluate the effectiveness of B12 therapy and folate. C. Liver enzymes: Liver function tests (AST, ALT, ALP) assess hepatocellular injury or dysfunction, which may affect medication metabolism but are not primary indicators of hematologic status or B12 deficiency. While chronic disease may affect liver function, these values would not directly explain fatigue in the context of pernicious anemia. D. Platelet count: Platelet count is included in the CBC but is more relevant to assessing bleeding or clotting risk rather than fatigue related to anemia. While severe vitamin B12 deficiency can sometimes cause pancytopenia, the primary focus in a client with persistent fatigue should be red blood cell indices and hemoglobin/hematocrit levels.