Metaphyseal sclerosis in an infant with anemia, seizures, or encephalopathy should raise suspicion for severe lead poisoning. These dense, radiopaque bands (“lead lines”) reflect impaired endochondral bone remodeling, resulting in retention of mineralized cartilage at the growth plate. Because lead lines generally appear at blood lead concentrations greater than 70 μg/dl, radiographs have limited value as a screening tool for lead poisoning. For further reading on the diagnosis and management of lead poisoning, see this NEJM review article.
Comment
Metaphyseal sclerosis in an infant with anemia, seizures, or encephalopathy should raise suspicion for severe lead poisoning. These dense, radiopaque bands (“lead lines”) reflect impaired endochondral bone remodeling, resulting in retention of mineralized cartilage at the growth plate. Because lead lines generally appear at blood lead concentrations greater than 70 μg/dl, radiographs have limited value as a screening tool for lead poisoning. For further reading on the diagnosis and management of lead poisoning, see this NEJM review article.