Materials for this week:
- Case discussion
- Pediatrics in Review on Lead Poisoning
- WA DOH Clinical Algorithm for Targeted Childhood Lead Testing
- Pediatric Environmental Health Specialty Unity (PEHSU) website
Take-home points for lead screening
- What is a safe blood lead level (BLL)? Based on strong research evidence, no measurable BLL is considered safe. Neurotoxicity associated with lower BLLs has been established by overwhelmingly consistent evidence from meta-analysis, so primary prevention of lead exposure is paramount. All detectable BLLs are reportable in WA State and the health department follows up with all BLLs > 5 mcg/dL.
- Why screen for lead? While lead is toxic to multiple body systems, the developing brain is particularly vulnerable. Most lead toxicity in the US is sub-clinical, only found on blood testing. Even low levels (<10mcg/dL) may be associated with behavioral problems (such as attention, aggression) and learning difficulties. Children aged 9-24 months are highest risk due to normal exploratory behavior – crawling, teething, putting non food objects in the mouth. Absorption across the gut is greater in children than adults.
- What are the sources of elevated lead levels? Ingestion of lead-containing dust or soil is the highest source, usually from old paint in homes built before 1950, but up through 1978, and homes from these eras being remodeled. As we have learned from Flint MI, lead is also in water sources, from contaminated water and old pipes. There are also newer sources of lead in imported products including candies, food, spices, make-up, and ceramics.
- Who should receive blood lead testing? In WA state, the 2016 guidelines identify children with these risk factors: 1) Lives in or regularly visits any house built before 1950 or built before 1978 with recent or ongoing renovations or remodeling, 2) From a low income family (<130% of the poverty level). (Federal law mandates screening for all children covered by Medicaid), 3) Known to have a sibling or frequent playmate with an elevated blood lead level, 4) Is a recent immigrant, refugee, foreign adoptee, or child in foster care, 5) Has a parent or principal caregiver who works professionally or recreationally with lead, 6) Uses traditional, folk, or ethnic remedies or cosmetics. Unfortunately, screening questionnaires have not reliably identified kids, as one of our residents found for a topic review at Harborview, so when in doubt, screen.
- What do you do with an elevated level? The PEHSU provides a summary of key next steps based on BLL results on their website. Next steps will include evaluation for anemia/low calcium and Vit D, since these may impact lead absorption, as well as determining the need for imaging or medical management.