Childhood lead poisoning

Although the average blood lead levels of Americans have markedly declined, a significant number of children remain at risk. This article discusses the mechanisms of lead poisoning and the screening of children for lead poisoning, and the treatment of symptomatic and asymptomatic children.     

Iron deficiency in lead poisoning

The anemia of lead poisoning is multifactorial. Of 44 hematologically evaluated children with class III or IV lead intoxication, 50 per cent were anemic and 39 per cent were iron deficient. Iron deficiency may play an important role in the anemia of lead poisoning. Early diagnosis and correction of nutritional deficiencies may decrease the metabolic toxicity of lead poisoning.     

Neonatal lead poisoning. An unusual clinical manifestation

A case of lead encephalopathy in a 2-month-old child is reported. Modes of poisoning are discussed and the unusual clinical manifestations of metallic brownish discoloration of nails and subdural effusion are presented. The possibility of lead poisoning as a cause of convulsions in neonates should be considered by doctors caring for these patients. Detailed history of lead exposure in prenatal and postnatal periods aids in early diagnosis and treatment which, thus, prevent severe neurological sequelae.     

Maternal perceptions of lead poisoning in children with normal and elevated lead levels.

INTRODUCTION: The purpose of this study was to examine mothers' perceptions of the severity and susceptibility of their children to lead poisoning and to determine if a correlation existed between mothers' knowledge of lead poisoning and their children's blood lead levels. It was thought that mothers of children with lead poisoning (lead levels > or = 10 micrograms/dL) would score lower on a test of their perceptions and knowledge of lead poisoning than would mothers of children with normal lead levels (lead levels < or = 9 micrograms/dL). METHOD: A cross-sectional study comparing scores of a questionnaire completed by mothers whose children had elevated blood lead levels and mothers whose children had normal blood lead levels was conducted. RESULTS: No difference was found in the median test score between the 2 groups. For the correct responses on a question-by-question comparison, significant difference existed between groups; however, the percentage of correct responses was not always greater for the mothers of children with normal blood lead levels. DISCUSSION: Mothers' perceptions and knowledge of lead poisoning were not associated with their children's blood lead levels.     

Severe cerebellitis following methadone poisoning

We report a 3-year-old girl with an unusual presentation of cerebellitis following ingestion of methadone. CT showed diffuse symmetrical swelling and oedema of the cerebellum resulting in compression of the fourth ventricle and hydrocephalus. The changes were confirmed on MRI with the addition of watershed injuries. These findings represent a toxic encephalopathy and have been reported in previous cases of heroin intoxication by inhalation, but rarely following opioid ingestion. The aetiology of the watershed infarcts is discussed.     

Six children with lead poisoning

Although most commonly seen in children from lower socioeconomic backgrounds, all children are at risk for lead poisoning. Management is a potential problem for all primary care providers. Because few individuals in the primary care practice of pediatrics have many patients with lead poisoning, it may be difficult to understand the nuances of management. We describe six patients, each of whom reflects different aspects of lead poisoning in children, and discuss the lessons we have learned in the course of their treatment. We have found that graphic representation of the blood lead and erythrocyte protoporphyrin values is helpful in the longitudinal follow-up of these youngsters.     

Prevention of childhood lead poisoning

Although past national public health efforts have reduced lead exposure significantly, lead poisoning remains the most common environmental health problem affecting American children. Currently, lead exposure occurs predominantly through ingestion of lead-contaminated household dust and soil in older housing containing lead-based paint; exposure can be increased with housing deterioration or renovation. Environmental prevention efforts focus on improvement in risk assessment, development of housing-based standards for lead-based paint hazards, and safe and cost-effective lead hazard remediation techniques. Educational efforts address parental awareness of lead exposure pathways, hygiene, and housekeeping measures to prevent ingestion of dust and soil. Blood lead screening is recommended either universally at ages 1 and 2 years or in a targeted manner where local health departments can document a low prevalence of elevated blood lead levels. Nutritional interventions involve provision of regular meals containing adequate amounts of calcium and iron and supplementation for iron deficiency. Lead chelation should complement environmental, nutritional, and educational interventions, when indicated. Collaboration of multiple federal agencies in a new strategy to eliminate childhood lead poisoning should further prevention efforts.     

Need for the lead mobilization test in children with lead poisoning

We evaluated the recommendation of the Centers for Disease Control, that children with moderate lead poisoning undergo the lead mobilization test (LMT) to determine the need for a full course of chelation treatment. Current criteria for selection for this test include a blood Pb concentration (bPb) between 25 and 55 micrograms/dl and an erythrocyte protoporphyrin level greater than 35 micrograms/dl. To determine whether the eligibility criteria could be refined to a smaller group of patients, we compared bPb determinations obtained on the day of the LMT in 198 children with moderate Pb poisoning to the results of the LMT. We found that children with bPb less than 25 micrograms/dl were unlikely to respond to the test dose of calcium disodium ethylenediamine tetraacetate with a Pb diuresis (24/25 patients had low urinary Pb excretion on the LMT). In contrast, 88% of children with bPb greater than or equal to 40 micrograms/dl were likely to excrete sufficient Pb to indicate the need for a full course of chelation. We conclude that the LMT is indicated for children with bPbs between 25 and 40 micrograms/dl. Children with bPb between 40 and 55 micrograms/dl may receive chelation therapy without having an LMT, if the performance of the LMT is not practical. Patients with levels less than 25 micrograms/dl should be followed clinically and removed from further Pb exposure.