Neuropsychologic testing of children with elevated BLL is the best indicator of the level of cognitive dysfunction. These tests can document therapy-related improvements in attention, visual-spatial abnormalities, and memory.5
Plain long-bone radiographs may be useful in identifying opaque lead lines that occur with chronic exposure and a BLL of 70 to 80 µg/dL; however, they are not recommended by the AAP.17 Abdominal radiographs can be ordered selectively to identify foreign objects, such as paint chips, providing an opportunity for bowel decontamination therapy to prevent further lead absorption. Selective use of neuroimaging studies, such as CT and MRI, can demonstrate cerebral edema and microhemorrhages and exclude structural lesions in children with an altered mental status suspected to be caused by lead toxicity.
CASE STUDY: AN ENVIRONMENTAL EXPOSURE
A 12-month-old Hispanic girl was evaluated in May 2005 at a County Health Department (CHD) clinic in a routine well-child checkup. The child was found to have an elevated blood lead level (BLL). Initial capillary BLL was 39 g/dL, and confirmatory venous BLL was 26 g/dL. The child was referred to the CHD Childhood Lead Poisoning Prevention Program for evaluation. A home visit and environmental investigation for lead exposure followed.
Medical history The child had no significant medical history. Her parents denied any symptoms or signs associated with lead poisoning. The girl had a good appetite and ate a well-balanced diet, with no use of supplemental vitamins or routine medication.
Housing The child resided in a rental home with her parents; no other children or pets lived with them. The home was a detached apartment, built before 1930. It was not located near a major highway or any lead-producing industries; however, nearby buildings were undergoing renovation. The home contained older plumbing, but the family primarily used bottled water.
Parental occupational history The father's work involved renovating older homes, and the child frequently visited his work site. His work clothes were laundered separately from the household laundry, and he removed his shoes before entering the home.
Nontraditional sources The parents denied use of home remedies, imported spices, or foreign candies but acknowledged using imported candles. Samples of the candles were negative for significant lead content. The parents had observed the child sucking her thumb and putting nonfood items such as paint chips in her mouth.
Potential exposure sources Lead hazards were identified on windows with peeling lead paint and areas of bare soil adjacent to the windows. The parents were advised to refrain from stripping the paint, to mulch areas with bare soil, to keep the child away from the father's work site, and to implement good hand washing and housekeeping practices.
Medical intervention The child's venous BLL was 33 µg/dL 1 month after the environmental inspection, and 6 weeks later, it was 46 µg/dL. The increasing BLL prompted hospitalization and administration of succimer chelation therapy. At discharge, a few days later, the BLL was 34 µg/dL. Subsequent BLL monitoring over the next 3 years showed a continuous decline, and the BLL drawn in February 2009 was 6 µg/dL.
Acknowledgement: This case was contributed by Dr. Aaron Hilliard and Dr Tiffany Turner, Duval County Health Department Childhood Lead Prevention Program, Jacksonville, Florida.
MANAGEMENT AND TREATMENT
Children with a confirmed BLL higher than 10 µg/dL require follow-up testing.2,17,21 A home evaluation should be performed if a child has a BLL higher than 15 to 19 µg/dL for 3 months or more or has an initial BLL higher than 20 µg/dL to determine the source of the lead exposure. Other members of the household should also be tested. Chelating agents are the standard treatment for acute and high levels of lead toxicity. Children with a BLL higher than 45 µg/dL should be treated with succimer. A lead level higher than 70 µg/dL is a medical emergency. Children with lead encephalopathy are best treated in a children's hospital with pediatric intensivists and other specialized resources (see Table 2).
PREVENTION AND PATIENT EDUCATION STRATEGIES
The Lead Contamination Control Act of 1988 gave the CDC authority to establish programs to prevent and eliminate childhood lead poisoning.22 As a result of this legislation, nearly 60 childhood lead-poisoning prevention programs have been established, state and national screening surveillance for lead has been enhanced, and targeted screening and case management guidelines for children with elevated BLL have been developed.
PAs should familiarize themselves with the available resources in their community and state. Anticipatory guidance should be provided to the parents and caregivers of young children, including identifying sources of lead in the child's environment and lead-prevention counseling.6 Community-specific risk-assessment questionnaires and appropriate BLL screening will help identify children at risk. Timely referrals to developmental and early enrichment programs are critical in establishing a lead-safe environment. So are agencies and community resources, such as local health departments, that provide on-site home and environmental assessments, targeted risk-reduction strategies, and ongoing case management for children with elevated BLL (see “Case study: An environmental exposure”).
Primary care clinicians are often the first line of defense in the efforts to prevent and eliminate childhood lead poisoning. A thorough risk assessment, targeted screening, appropriate caregiver education, and prompt referral can help eliminate the effects of lead exposure in children. JAAPA
Patti Ragan works for the Florida Department of Health, Bureau of Epidemiology & Florida Epidemic Intelligence Service Program, Tallahassee, Florida. Tiffany Turner worked for the Duval County Health Department, Division of Environmental Health and Disease Control, Childhood Lead Poisoning Prevention Program, Jacksonville, Florida, at the time this article was written. They have indicated no relationships to disclose relating to the content of this article.
Acknowledgement: The authors wish to thank Aimee Pragle, MS, Julie Kurlfink, and Juanita Jones, MPH, from the Childhood Lead Poisoning Prevention Program, Bureau of Environmental Public Health Medicine, Florida Department of Health, for their contributions to this article.
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