Case:

Rosalie is a 2 year-old girl who comes in for her regular checkup. At the end of the visit, when you hand a lab slip to check hemoglobin and lead levels, her mom asks, “Why should we check her blood again? We did that last year and everything was fine. Last time, they had to try 3 different times to get blood, and I really don’t want her to get stuck again.”

What do you say?

 

child

Why should we care about elevated blood lead levels (BLLs)?

  • NO BLOOD LEAD LEVEL IS CONSIDERED SAFE
  • Toxic Effects to the Following Organ Systems [Papanikolaou NC et al, 2005]:

    • CNS
      • Developmental Delay: Decline in IQ, reduced academic performance, hyperactivity, increased aggression, etc (can been seen at levels ≥35μg/dL).
      • Seizures
      • Encephalopathy (BLL usually > 100μg/dL)
    • Gastrointestinal
      • Constipation
      • Abdominal Pain
    • Hematologic (effects observed at levels as low as 10 μg/dL)
      • Microcytic Anemia
    • Cardiac, Renal

Epidemiology

 

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  • According to the CDC, in 2014 4% of children tested in the United States had elevated BLL (>5 μg/dL)
    • In Rhode Island, slightly more children (5%), had elevated BLLs
  • Unfortunately, of the >24 million children <72 months, only 10% were actually screened.
    • In Rhode Island, 39% of children <72 months were screened
  • Elevated Lead levels are more likely to affect children who are: [MMWR, 2013]
    • Black, non-Hispanic
    • Live in houses built before 1950
    • Receive Medicaid
    • Low socioeconomic status
  • Where is this lead located?
    • Lead Paint (used in older houses; imported hand painted dishes, toys)
    • Contaminated Soil (usually where leaded gasoline deposited)
    • Water (Lead pipes); well water
    • Natural Remedies (certain health tonics, digestive aids, or colic remedies)

When should you check Rosalie’s blood lead level?

  • According to the CDC:
    • Universal screening of all children, at 1 and 2 years of age (of note, ALL children on Medicaid MUST be screened)
  • In Rhode Island it is mandatory to screen all children who are under 36 months at least twice  (www.health.ri.gov). This is usually done at 12 and 24 months
    • Children should be screened annually through 6 years of age
      • After 2 negative blood levels, use risk assessment and screening tools to guide workup.

Her lead level returns elevated, what should you do?

  • Consult with your State’s Lead Prevention Program Recommendation. Table below is from Rhode Island Department of Health
Venous Blood Level Confirmation Interval Recommended actions for Primary Care Providers
< 5 μg/dl No confirmation needed Provide Lead education and continue to assess for lead exposure
5- 14 μg/dl Retest within 3 months ·       Explain lead level to parents

·       Assess Nutrition

·       Test Siblings < 6yo

·       Provide Lead Education

15-19 μg/dl Retest within 3 months ·       Same recommendations as above

·       Dept. of Health will refer to lead center

20- 44 μg/dl Retest within 1 week ·       Refer for evaluation and treatment to local lead clinics
≥ 45 μg/dl Repeat Immediately ·       As above, but consider hospitalization

Adapted from Rhode Island Department of Health Lead Screening and Referral Guidelines. Updated September 2013.

Rosalie’s lead level is 56, which is confirmed on repeat testing. What is the next step?

Moderate Intoxication (45-69mcg/L)

  1. Once level is confirmed, chelation should be started as follows:
    1. DMSA (Succimer)- this is the oral version of dimercaprol
    2. CaNa2EDTA- for children who cannot tolerate DMSA
    3. D-penicillamine (third line agent for children who cannot take 1 or 2 due to adverse affect).

Severe Intoxication (70mcg/L or encephalopathy)

  1. Hospitalize
  2. Repeat labs (especially serum lead); if confirmed
  3. Chelate
    1. Dimercaprol (BAL)
    2. Calcium disodium edetate (CaNa2EDTA)
  4. Monitor
  5. Disposition dependent on availability of follow-up, ensuring lead free household

Summary:

  • No blood lead level is considered safe
  • Lead intoxication remains an important cause of preventable developmental delay
  • All children should be screened at 12 and 24 months of age
  • Know your state’s guidelines on Lead screening and Referral Guidelines!

 

Faculty Reviewers: Shuba Kamath, MD; Chandan Lakhiani, MD

 

Lead Poisoning in Popular Culture

 

References:

“Blood Lead Levels in Children Aged 1–5 Years — United States, 1999–2010.”  Morbidity and Mortality Weekly Report. 2013;62(13);245-248

Chandran L et al. “Lead Poisoning: Basics and New Developments.” Pediatrics in Review. 2010;31(10)399- 406.

Dietrich KN et al. “Effect of Chelation Therapy on the Neuropsychological and Behavioral Development of Lead-Exposed Children After School Entry.” Pediatrics. 2004;114(1)19-26.

Lowry JA et al. “Childhood lead poisoning: Management.”  UpToDate.  http://www.uptodate.com/contents/childhood-lead-poisoning-management. Accessed July 10, 2016.

Papanikolaou NC et al. “Lead toxicity update. A brief review.” Med Sci Monit.. 2005;11(10)RA329-336.

Schmidt, Silke and Dee Hall. “Failure at the faucet: Lead in drinking water poses danger for children, pregnant women.” http://wisconsinwatch.org/2016/01/140477/

“Lead Screening and Referral Guidelines.” Rhode Island Department of Health. September 2013