I conclude that this patient has thalassemia; however, as indicated in Table 2, the clinical severity of thalassemia is variable. She obviously does not have thalassemia major, which by definition requires long-term transfusion therapy for survival. Therefore, does she have thalassemia intermedia, with its dramatic stress erythropoiesis and splenomegaly, or does she have thalassemia minor (heterozygous thalassemia or thalassemia trait), which is essentially asymptomatic? Because of the high gene frequency, one fifth to one third of Cambodians have thalassemia trait as an incidental finding. Also, if thalassemia intermedia is severe enough to produce extramedullary hematopoiesis, it would be unusual for it to remain undetected until age 62. Thus, although it is tempting to ascribe this patient's findings to thalassemia intermedia, we need more evidence that her thalassemia is more severe than thalassemia trait. Perhaps the peripheral-blood smear will provide some clues.
Dr. Aliyah R. Sohani: The peripheral-blood smear showed marked anisopoikilocytosis, with microcytic hypochromic cells, numerous teardrop and target cells, and occasional elliptocytes, spherocytes, and fragmented red cells (Figure 2AFIGURE 2
Peripheral-Blood Smear, Core-Biopsy Specimen of the Paraspinal Mass, and Bone Marrow–Biopsy Specimen and Aspirate.
). Mild polychromasia was present, although no nucleated red cells were seen. Platelets and white cells were morphologically unremarkable.
Dr. Benz: This smear clearly shows considerably more anisocytosis and poikilocytosis than one typically sees in thalassemia minor, which is characterized by a relatively uniform hypochromia and microcytosis. Unfortunately, a reticulocyte count was not available. However, there are large metachromatic erythrocytes, which are suggestive of an elevated reticulocyte count and brisk erythropoiesis.