ABSTRACT
In the neurocutaneous porphyrias, fecal porphyrins are increased during and between acute attacks. Porphyrias are inherited disorders of enzymes involved in the biosynthesis of heme. Sideroblastic anemia comprises a heterogeneous group of disorders characterized by ring sider-oblasts in the bone marrow, intramedullary cell death of erythroblasts leading to ineffective erythropoiesis, and anemia. Sideroblastic anemia can be hereditary, in which case the disorder is inherited as an autosomal dominant trait. Hereditary sideroblastic anemia is inherited as an autosomal dominant trait. Exposure to chloramphenicol, isoniazid or heavy metals can lead to sideroblastic anemia. Likewise, alcoholism may result in sideroblastic anemia. Bone marrow aspirates from patients with idiopathic sideroblastic anemia show intense megaloblastoid erythroid hyperplasia. Patients with idiopathic sideroblastic anemia may be asymptomatic and not require blood transfusions. In approximately 7–10% of patients with idiopathic sideroblastic anemia, evolution into acute nonlymphoblastic leukemia occurs.
