Lead lines

Abstract

An 11-month-old female infant was brought in with a 2-day history of vomiting, generalised tonic-clonic seizures, and somnolence. On examination, she was pale, hypotonic, and comatose with a bulging anterior fontanelle. Both pupils were dilated. Cerebrospinal fluid was normal, so we considered lead poisoning as a cause of encephalopathy. Full body radiographs showed dense metaphyseal bands in all the long bones without any flaring or cupping (figure). Haemoglobin was 85 g/L, free erythrocyte protoporphyrin (FEP) was 43 mg/g of haemoglobin, and the blood lead was 297 mg/L. The patient's father made imitation jewellery at home using lead-based paints which were probably the source of lead poisoning. Despite treatment with intravenous edetate disodium calcium, the patient had cardiac arrest and died. The parents were counselled regarding the possibility of lead poisoning in future children.Dense metaphyseal bands or lead lines indicate radioopaque bone at the metaphysis of growing bones and are fairly typical of lead poisoning in young infants with acute encephalopathy. Lead inhibits osteoclastic remodelling, but it has no effect on osteoblasts. Although lead ions are deposited on hydroxyapatite crystal, lead contributes very little to the metaphyseal density, which is due to exuberant calcium deposition in the zone of provisional calcification.Note to potential authorsThe Lancet currently has a large stock of clinical pictures ready for publication. Regretfully, we will not be able to accept any new submissions until January 2004. An 11-month-old female infant was brought in with a 2-day history of vomiting, generalised tonic-clonic seizures, and somnolence. On examination, she was pale, hypotonic, and comatose with a bulging anterior fontanelle. Both pupils were dilated. Cerebrospinal fluid was normal, so we considered lead poisoning as a cause of encephalopathy. Full body radiographs showed dense metaphyseal bands in all the long bones without any flaring or cupping (figure). Haemoglobin was 85 g/L, free erythrocyte protoporphyrin (FEP) was 43 mg/g of haemoglobin, and the blood lead was 297 mg/L. The patient's father made imitation jewellery at home using lead-based paints which were probably the source of lead poisoning. Despite treatment with intravenous edetate disodium calcium, the patient had cardiac arrest and died. The parents were counselled regarding the possibility of lead poisoning in future children. Dense metaphyseal bands or lead lines indicate radioopaque bone at the metaphysis of growing bones and are fairly typical of lead poisoning in young infants with acute encephalopathy. Lead inhibits osteoclastic remodelling, but it has no effect on osteoblasts. Although lead ions are deposited on hydroxyapatite crystal, lead contributes very little to the metaphyseal density, which is due to exuberant calcium deposition in the zone of provisional calcification. Note to potential authors The Lancet currently has a large stock of clinical pictures ready for publication. Regretfully, we will not be able to accept any new submissions until January 2004.