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Disclosure Statement. No financial interest or affiliation concerning material discussed in this presentation Will not discuss any non FDA approved or investigational drugs/medical devices. Congenital Lead Poisoning. Nachammai Chinnakaruppan,MD Neonatologist
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Disclosure Statement • No financial interest or affiliation concerning material discussed in this presentation • Will not discuss any non FDA approved or investigational drugs/medical devices
Congenital Lead Poisoning Nachammai Chinnakaruppan,MD Neonatologist Lehigh Valley Health Network, Allentown, PA
Outline • Case presentation • Association between BLL and development • ??Screen pregnant women • Strategies to enhance development • Strategies to decrease exposure • Latest CDC recommendations on prevention of childhood lead poisoning
Introduction • Lead poisoning is the most common preventable cause of neurotoxicity in children • Associated with impaired cognitive, motor, and behavioral abilities Binns et al Advisory Committee on Childhood Lead poisoning , Pediatrics 2007
Introduction-continued • In 1991,CDC defined the BLL of concern to be 10 mcg/dl • Advisory Committee on CLP concluded that there is no safe BLL. • BLL<10 have been associated with decreased scores on psychometric tests in children Dietrich et al,Treatment of Lead exposed children in clinical trial, Pediatrics 2004)
The Mother • 23 yo Mexican woman 36 weeks into a gestation is screened for lead • Result: 58.4 mcg/dl • Rescreened 4 days later: 57.2 mcg/dl • Anemic Hb 9.5g% • Prescribed iron supplements • Spontaneous labor 2 weeks later
The Child • Normal term female infant, AGA 3030g • Good Apgars, normal neurological exam • Sent to nursery • Pb level available at 36 hours of age: 72 mcg/dl • Other labs: Hb 17g%, FEP 175 mcg/dl, No basophillic stippling in peripheral blood smears
Basophilic Stippling Lead poisoning (arrow indicates an erythrocyte with basophilic stippling, NEJM 2005.
Treatment Options • CaNa2EDTA • BAL • BAL/ CaNa2EDTA • Succimer • Other
Management • Transferred to NICU • Consult with toxicologist • Decision made to perform a double volume exchange transfusion despite the risks of the procedure • BLL 6 hours after exchange was 11mcg/dl • Also started on chelation therapy
Management- Continued • 6 doses of IM dimercaprol (BAL) • Infusion of calcium disodium ethylenediaminetetraacetate (CaNa2EDTA) • Oral succimer for 3 weeks • Infant discharged home on full feeds and normal discharge neurological exam
Double volume exchange transfusion BAL/CaNa2EDTA succimer Mother’s Blood lead
Follow-Up • At 1 year, healthy, not on any medications • Weight at 10%, length 50%, head circumference 25% • Bayleys assessment showed cognitive score of 135, motor score of 103 • 2 y.o sister with BLL of 8mcg/dl
“Sources” found • Treats made in Mexico • Flowered bowls made in Thailand • Gibson plates made in China • Express china bowl made in China • Atelier plate made in Indonesia • Small metal pitcher made in Colombia • Cerebyl (Suplemento Alimentico) from Mexico
Sources -Continued • Mother has pica • Lipstick (tested hers=negative) • Chews nail polish( hers=negative) • Eats “bean stones” • Chews bottle tops and knitting needles and on her necklace: all tested negative
Lead And The Brain • Pb disrupts synapse formation • Increases transmitter release • Decreases stimulated transmitter release • Interferes with neurotransmission • Decreases synapse formation • Decreases neuron growth Johnston et al Current Opinions Neurology 1998
Is there a safe BLL? • 2002-2004, CDC LPPC analyzed 23 reports on 16 populations and concluded that BLL →1/ Cognitive function
Is there a safe BLL- continued • IQ decreases more than 7 points over the first 10 mcg/dl increase in lifetime average BLL • Likely causal association • NO SAFE BLL
Lead in Pregnancy • 0.5% women still have BLL more than 10mcg/dl • Pb moves freely from mother to baby by diffusion and there is net accretion over time • Results in babies that are growth restricted, delayed dentition and adverse neurological outcomes Gardella Obst and Gyn Survey 2001
Routine Prenatal Screening?? • Argue that this identifies at risk women and remove the lead sources to decrease neonatal morbidity • Don’t know how to respond to the blood screens. Who responds? • Chelation well tolerated by mothers but it mobilizes Pb stores and can potentially increase transmission to the fetus
Recommended Lead Risk Assessment Questions for Pregnant Women • Were you born, or have you spent any time, outside of the United States? • In NYC, approximately 95% of identified lead-poisoned pregnant women are foreign-born. Countries of birth in descending order of frequency include Mexico, India, Bangladesh, Russia, Pakistan, Ecuador, Haiti, Jamaica, • Morocco, Dominican Republic, Guatemala, Guyana, El Salvador, Gambia, Ghana, Honduras, Israel, Ivory • Coast, Korea, Nepal, Sierra Leone, and Trinidad. • During the past 12 months, did you use any imported health remedies, spices, foods, ceramics, or cosmetics? • At any time during your pregnancy, did you eat, chew on, or mouth non-food items such as clay, crushed pottery, soil, or paint chips? • In the last 12 months, has there been any renovation or repair work in your home or apartment building? • Have you ever had a job or hobby that involved possible lead exposure, such as home renovation or working with glass, ceramics, or jewelry?
Anticipatory Guidance and Risk Reduction Education For Pregnant Women • Avoid using health remedies, spices, foods, or cosmetics from other countries. • Avoid using clay pots and dishes from other countries to cook, serve, or store food and do not use pottery that is chipped or cracked. • Never eat non-food items such as clay, soil, pottery, or paint chips. • Stay away from any repair work being done in the home. • Avoid jobs or hobbies that may involve contact with lead, such as home renovation or working with glass, ceramics, or jewelry.
Management Options • Chelation of mother • Prenatal • Postnatal • Chelation of newborn • Role of prenatal counseling, induction, termination • Timing of lead screening • Breastfeeding • Role of exchange transfusion in the newborn with extremely elevated BLL
Why concentrate on the Newborn? • Chelation at 12 months should improve outcome • DB Placebo controlled 1994-2003, multiple centers (n=800) • Randomized and stratified by BLL and language to treatment or placebo • Tested at 7 years • All kids received lead control measures • Results: Chelation decreased BLL for 6 months with NO benefit in cognition, behavior and neuromotor end points • SO PREVENTION is the only way Rogan et al Pediatrics 2007
Strategies to Enhance Development • Elevated BLL does not guarantee problems • Greater impact on the at risk children i.e. those with other environmental, genetic, biological, social risk factors. Nurture them. Early intervention
Strategies to Decrease Exposure • 4.1 million homes have lead paint • Home inspection limited to children with elevated BLL • Funds to repair not available • Case management to homes with BLL>10 • Relocating families during renovation, containing dust • Screen at risk 12mth, 24 mths, (36 to 72 mths) • Education
Advisory Committee on CLPP-Clinicians • Anticipatory Guidance • Occupation • Toys, folk remedies, candy, make-up • Developmental Assessment • Nurture Kids • Use good labs
Advisory Committee on CLPP-Government • Decrease Lead Based Hazard • Safe Elimination of Lead Hazards • Decrease Pb exposure in Food • Primary Prevention in Highest risk areas • Additional Research
Conclusion • No consensus on managing the results of a gestational screen • Focus should be on education of target population to decrease lead exposure