<prompt> Answer this question truthfullyWhat is the recommended next step in the workup for a patient who is found to have microcytic anemia, with a mean corpuscular volume MCV of less than 80, regardless of the underlying cause?  <response>: <reason> The most appropriate next step in the workup for this patient is to perform iron studies, specifically measuring the ferritin level. Microcytic anemia can be caused by a variety of factors, including iron deficiency, thalassemia, and anemia of chronic disease. Iron studies, including serum iron, total iron-binding capacity TIBC, and ferritin, can help differentiate between these etiologies. A low ferritin level suggests iron deficiency anemia, while a normal or high ferritin level suggests anemia of chronic disease or thalassemia. Treatment options will depend on the underlying cause of the microcytic anemia. 