Introduction

"Preconception and prenatal counseling sessions present opportunities to prevent lead exposures that could lead to possibly devastating and lifelong effects."

Office of Surgeon General 2008,

With the move away from a designated "level of concern," a new algorithm is needed to provide clinicians with guidance on responding appropriately to the lower range of BLLs. No blood lead threshold for adverse health effects has been identified in children.

Treatment and management strategies for children whose blood levels are equal to or greater than the reference value include nutritional education and intervention (as indicated), lead educational intervention, ongoing monitoring, and coordination with other organizations.

Chelation therapy is considered a mainstay in the medical management of children with BLLs > 45 μg/dL, but should be used with caution. Consultation with a physician with expertise and experience in treating children with lead toxicity is recommended.

Therefore, prior to suggesting or prescribing chelation agents, it would be prudent to consult with a

• Local or state lead poisoning prevention program, a
• Local poison control center, and/or a
• Regional Pediatric Environmental Health Specialty Unit (PEHSU).

Evaluation and Intervention Strategies for Children with BLLs at or Above the Reference Value

When the neurological exam, milestones, or behavior suggest it, further neurobehavioral testing or evaluation for Attention Deficit Hyperactivity Disorder (ADHD) may be indicated.

Table 8 shows ACCLPP Recommended Actions Based on BLLs. It is important to mention the increased urgency of these interventions as BLLs increase to reduce the damage to the persons exposed, especially children.

A BLL of ≥ 45 µg/dL is not a threshold for chelation, but a guideline. Professional judgment should guide the decision to chelate a child or adult, based on their individual clinical considerations. In some instances, a patient may need to be chelated at somewhat lower BLLs.

Table 8: ACCLPP Recommended Actions Based on BLL [ACCLPP 2012]

^*The scope of an "environmental assessment" will vary based on local resources and site conditions. However, at a minimum this would include a visual assessment of paint and housing conditions, but may also include testing of paint, soil, dust, and water and other lead sources [Levin et al. 2008]. This may also include looking for exposure from imported cosmetics, folk remedies, pottery, food, toys, etc. which may be more important in low-level lead exposure [ACCLPP 2012].

Coordination of care with local authorities and organizations, including local Childhood Lead Poisoning Prevention programs, is essential to

• Initiate prompt investigation for the source of lead exposure, and
• Plan a response strategy.

Although these services are typically outside of the clinician's role, medical and environmental interventions should be implemented simultaneously to best protect the child.

In addition, families with children whose BLLs are above the reference value should be given access to services that provide education about:

• Existing codes or ordinances,
• Lead-safe housing rules,
• Disclosure requirements,
• Landlord responsibilities,
• Risk factors for lead exposure in the home and at work, and
• Steps for maintaining a lead safe home (lead hazard identification and repair, lead dust testing, EPA and state Renovation, Repair and Painting (RRP) requirements, and do-it-yourself precautions).

Home visits by CLPPP staff, community health workers, Maternal and Child Health home visiting programs, and other systems to assess the home should:

• Advise occupants of lead hazards,
• Make referrals in response to identified lead hazards, and
• Report observations and lead test results.

Assistance and guidance is available regarding:

• Housing codes, including legal services for egregious situations like evictions and serial offender property owners and referrals to code enforcement,
• Landlord violations of RRP, and
• Other lead rules.

"Low health literacy is a threat to the health and wellbeing of Americans. And low health literacy crosses all sectors of our society. All ages, races, incomes, and education levels are challenged by low health literacy."

Rear Admiral Kenneth P. Moritsugu, MD, MPH Acting United States Surgeon General, December 2006

Health Literacy is the capacity to obtain, process and understand basic health information and services needed to make appropriate health decisions.

Approximately one-half of the adult population may lack the needed health literacy skills to best utilize the U.S. healthcare system. Low health literacy has been linked to poor health outcomes such as higher rates of hospitalization and less frequent use of preventive services [CDC 2013f].

CDC Healthy Homes and Lead Poisoning Prevention Program addresses health literacy. It created several resources to help communicate about childhood lead poisoning.
https://www.cdc.gov/nceh/lead/tools/LeadLiteracy.htm

Recommendations on Medical Management of Childhood Lead Exposure and Poisoning

No level of lead in the blood is safe. In 2012, the CDC established a new "reference range upper value" for BLLs (5 µg/dL), thereby lowering the level at which evaluation and intervention are recommended.

Effective screening policies and practices should ensure that the children of high-risk families (e.g., families on Medicaid) are screened, and that lead-exposed children or children with elevated BLLs receive key environmental interventions and case management services [ACCLPP 2012].

Table 9. Clinical Recommendations Based on Blood Lead Levels (BLLs) [PEHSU 2013]

Given the challenges involved in measuring BLLs as low as 5 µg/dL, quality assurance practices will need to be updated with the goal of improving accuracy and repeatability of BLL testing results.

Management of Children with BLLs Above 45 µg/dL

Chelation therapy is considered a mainstay in the medical management of children with BLLs > 45 µg/dL. However, this level is a guideline, not a threshold for hospitalization and/or chelation, and should be used with caution. Professional judgment should drive determinations of when to chelate. In some instances, a patient may need to be chelated at somewhat lower BLLs. Therefore, prior to suggesting or prescribing chelation agents, primary care providers should consult with their local or state lead poisoning prevention program, local poison control center, or regional Pediatric Environmental Health Specialty Unit (PEHSU) for the names of accessible physicians that have both expertise and experience with chelation for lead toxicity.

A child with an elevated BLL and signs or symptoms consistent with encephalopathy should be chelated in a center capable of providing appropriate intensive care services [ACCLPP 2012].

Physicians who suspect an unusual environmental cause for an illness will often find it useful to contact an expert in pediatric environmental medicine.

• The Pediatric Environmental Health Specialty Units (PEHSU), located in the ten Federal Regions of the United States and in Canada, can provide information, assistance, and referral for clinical evaluation and treatment if environmental exposures are verified (for additional information regarding the PEHSU, visit: http://www.pehsu.net/.
• Regional poison control contact information is available at: http://npic.orst.edu/health/poison.htm.
• CDC's Lead Poisoning Branch is an information resource available to clinicians at: https://www.cdc.gov/nceh/lead/about/program.htm.

Because there are potential side effects associated with each chelating drug, and because treatment protocols differ for each, it is vital that physicians with experience in chelation therapy be consulted before any chelation therapy is begun [AAP 1995].

An accredited regional poison control center, a university medical center, or a state or local health department can help identify an experienced physician.

Note also that the CaNa₂EDTA (i.e., edetate calcium disodium, Calcium EDTA) mobilization (challenge) test is no longer recommended because of its difficulty, expense, and potential for increasing lead toxicity [ACMT 2013; AAP 1995].

The utility of provoked urine tests for the diagnosis of metal poisoning has been addressed previously by the American College of Medical Toxicology [ACMT 2010]. It published a position statement recommending against the use of this test. Similarly, authors from the ATSDR and CDC have detailed the problems with provoked urine tests and have concluded that they should not be used as diagnostic tools [Risher and Amler 2005]. Yet despite these recommendations against the use of provoked urine testing by respected organizations, the test is still commonly used and recommended by some practitioners [Ruha 2014].

Potential Medical Error

There are several commercial drugs with the active ingredient EDTA. Only CaNa₂EDTA (also known as calcium disodium versenate or edetate calcium disodium) is appropriate for chelation. Na₂EDTA (disodium ethylenediaminetetraacetic acid) is not appropriate for chelation.

Please write your script carefully and legibly to avoid mistakes with chelating agents.

Ongoing Monitoring For Lead-Exposed Children

For the child identified with BLL results greater than or equal to the reference value, ongoing monitoring of BLL is indicated during and after appropriate medical, educational, and environmental interventions (See Table 9).

BLLs that increase may be indicative of

• An unrecognized source of exposure,
• Inappropriate abatement activities,
• Failure to mitigate the identified hazard, or
• The redistribution of lead stores within the child's body.

For the child with an increasing BLL, additional medical and environmental evaluation and interventions may be necessary, along with ongoing coordination of care with the local Childhood Lead Poisoning Prevention Program (CLPPP).

This monitoring is essential to identify a given source of lead, help determine if there is any ongoing exposure, and to verify the decline in BLL after lead sources have been reduced or eliminated. Ongoing monitoring is also essential for children undergoing chelation [AAP 1995, CDC 2002].

Table 10. Ongoing Monitoring for Lead-Exposed Children^a

^aSeasonal variation of BLLs exist and may be more apparent in colder climate areas. Greater exposure in the summer months may necessitate more frequent follow-up.

^*Some case managers or PCPs may choose to repeat blood lead tests on all new patients within one month to ensure that their BLL is not increasing more quickly than anticipated [ACCLPP 2012].

Progress Check