ITEMS IN AFP WITH MESH TERM:
Alpha and Beta Thalassemia - Article
ABSTRACT: The thalassemias are a group of inherited hematologic disorders caused by defects in the synthesis of one or more of the hemoglobin chains. Alpha thalassemia is caused by reduced or absent synthesis of alpha globin chains, and beta thalassemia is caused by reduced or absent synthesis of beta globin chains. Imbalances of globin chains cause hemolysis and impair erythropoiesis. Silent carriers of alpha thalassemia and persons with alpha or beta thalassemia trait are asymptomatic and require no treatment. Alpha thalassemia intermedia, or hemoglobin H disease, causes hemolytic anemia. Alpha thalassemia major with hemoglobin Bart's usually results in fatal hydrops fetalis. Beta thalassemia major causes hemolytic anemia, poor growth, and skeletal abnormalities during infancy. Affected children will require regular lifelong blood transfusions. Beta thalassemia intermedia is less severe than beta thalassemia major and may require episodic blood transfusions. Transfusion-dependent patients will develop iron overload and require chelation therapy to remove the excess iron. Bone marrow transplants can be curative for some children with beta thalassemia major. Persons with thalassemia should be referred for preconception genetic counseling, and persons with alpha thalassemia trait should consider chorionic villus sampling to diagnose infants with hemoglobin Bart's, which increases the risk of toxemia and postpartum bleeding. Persons with the thalassemia trait have a normal life expectancy. Persons with beta thalassemia major often die from cardiac complications of iron overload by 30 years of age.
Lightening the Lead Load in Children - Article
ABSTRACT: More than 4 percent of preschool-aged children in the United States have blood lead levels above 10 microg per dL (0.50 pmol per L), and these levels have been associated with a decline in IQ. The Centers for Disease Control and Prevention advocates the use of a screening questionnaire to identify lead exposure or toxicity in all children. Primary prevention through the removal of lead from gasoline and paint has led to a reduction of blood lead levels in children. Secondary prevention through paint hazard remediation is effective in homes that have a high lead burden. Children with lead levels of 45 to 69 microg per dL (2.15 to 3.35 pmol per L) should receive chelation therapy using succimer (DMSA) or edetate calcium disodium (CaNa2EDTA). Use of both CaNa2EDTA and dimercaprol (BAL in oil) is indicated in children with blood lead levels higher than 70 microg per dL (3.40 micromol per L). Current treatment recommendations are based on the reduction of blood lead levels, which may not represent a significant overall reduction of the lead burden. Clinical trials of existing agents are needed to determine patient-oriented outcomes, such as the effect on IQ.