eMedicine Specialties > Neurology > Neurotoxicology

Lead Encephalopathy: Follow-up

Author: Adam K Rowden, DO, Assistant Professor of Emergency Medicine, Thomas Jefferson University; Director, Division of Toxicology, Department of Emergency Medicine, Albert Einstein Medical Center; Consulting Toxicologist, Children's Hospital of Philadelphia
Coauthor(s): Christopher P Holstege, MD, Associate Professor of Emergency Medicine and Pediatrics, University of Virginia; Director, Division of Medical Toxicology, Center of Clinical Toxicology; Medical Director, Blue Ridge Poison Ctr, Associate Medical Toxicology Fellowship Director, VA Dept of Health; J Stephen Huff, MD, Associate Professor, Emergency Medicine and Neurology, Department of Emergency Medicine, University of Virginia Health Sciences Center; Rika Nagakuni O'Malley, MD, Fellow, Division of Toxicology, Department of Emergency Medicine, Albert Einstein Medical Center
Contributor Information and Disclosures

Updated: Oct 26, 2009

Follow-up

Further Outpatient Care

  • After chelation, the blood lead level should be rechecked in 7-21 days to determine whether repeat chelation therapy is required.
  • Do not discharge patients from the hospital until they can go to a lead-free environment.

Transfer

Chelation therapy, especially in the setting of encephalopathy, can be complicated. Consider transfer to an institution that is capable of managing an encephalopathic patient and also has a provider experienced in lead poisoning and chelation therapy.

Deterrence/Prevention

  • In cooperation with local health departments, the physician should educate families about the following:
    • Causes and effects of lead poisoning
    • Relationship between blood lead level and anticipated medical or neuropsychological problems
    • Importance of follow-up or serial blood lead level determinations to monitor effects of treatment and environmental lead abatement
    • Identifying and eliminating possible sources of lead exposure
    • Increased lead absorption in patients with iron-deficiency anemia
    • Local resources about lead exposure and treatment
  • Each patient requiring treatment for lead toxicity should be reported to local health authorities, so that they may initiate appropriate environmental evaluation and lead abatement.

Prognosis

  • Lead poisoning in children has been associated with lower intelligence quotient (IQ) scores. Prospective cohort studies have demonstrated effects with blood lead levels as low as 10 mcg/dL. Cohort studies demonstrate an effect regardless of socioeconomic group and indicate a loss of 3 IQ points for every 10 mcg/dL blood lead level above 10 mcg/dL.15,16,17,18
  • Impairment of attention also may result from lead poisoning, creating a clinical syndrome difficult to distinguish from attention deficit hyperactivity disorder.
  • Fine motor coordination may be impaired, with one cohort study suggesting a dose-effect relationship between incoordination and lifetime postnatal lead exposure.5
  • Both receptive and expressive language may be impaired with lead poisoning. Verbal comprehension and auditory processing have been reported in affected children.
  • With occupational exposure, progressive cognitive decline years after the exposure has terminated has been documented.

Patient Education

See Deterrence/Prevention.

Miscellaneous

Medicolegal Pitfalls

  • The primary medical legal pitfall is not considering lead as a potential cause of encephalopathy in a child or adult. Lead toxicity is a tremendous mimicker of other diseases.
  • Another pitfall is failure to assess the source of lead. Children in particular should not be allowed to return to a lead-contaminated environment. Involvement of the local Health Department can assist in assessment of the source of lead.

Special Concerns

Lead can cross the placenta. Blood lead levels tend to remain constant throughout pregnancy in women who were exposed to lead previously, even if no additional exposure to lead is present. Further occupational exposure or ingestion of lead may result in harm to the fetus. This may range from delay in later cognitive development to stillbirth, depending on the extent of exposure.

 
Acknowledgments

The authors and editors of eMedicine gratefully acknowledge the contributions of previous author David A Griesemer, MD to the development and writing of this article.



More on Lead Encephalopathy

Overview: Lead Encephalopathy
Differential Diagnoses & Workup: Lead Encephalopathy
Treatment & Medication: Lead Encephalopathy
Follow-up: Lead Encephalopathy
References
[ CLOSE WINDOW ]

References

  1. Stewart WF, Schwartz BS, Davatzikos C, et al. Past adult lead exposure is linked to neurodegeneration measured by brain MRI. Neurology. May 23 2006;66(10):1476-84. [Medline].

  2. Nawrot TS, Thijs L, Den Hond EM, et al. An epidemiological re-appraisal of the association between blood pressure and blood lead: a meta-analysis. J Hum Hypertens. Feb 2002;16(2):123-31. [Medline].

  3. Bressler J, Kim KA, Chakraborti T, Goldstein G. Molecular mechanisms of lead neurotoxicity. Neurochem Res. Apr 1999;24(4):595-600. [Medline].

  4. Norman EH, Bordley WC, Hertz-Picciotto I, Newton DA. Rural-urban blood lead differences in North Carolina children. Pediatrics. Jul 1994;94(1):59-64. [Medline].

  5. Dietrich KN, Berger OG, Succop PA. Lead exposure and the motor developmental status of urban six-year-old children in the Cincinnati Prospective Study. Pediatrics. Feb 1993;91(2):301-7. [Medline].

  6. Fluri F, Balestra G, Christ M, Marsch S, Fuhr P, Rüegg S. Stimulus-induced rhythmic, periodic or ictal discharges (SIRPIDs) elicited by stimulating exclusively the ophthalmic nerve. Clin Neurophysiol. Aug 2008;119(8):1934-8. [Medline].

  7. Holstege CP, Ferguson JD, Wolf CE, et al. Analysis of moonshine for contaminants. J Toxicol Clin Toxicol. 2004;42(5):597-601. [Medline].

  8. American Academy of Pediatrics Committee on Environmental Health. Lead exposure in children: prevention, detection, and management. Pediatrics. Oct 2005;116(4):1036-46. [Medline].

  9. Elevated Lead in D.C. Drinking Water – A Study of Potential Causative Events, Final Summary Report. EPA; August 2007. [Full Text].

  10. Carton JA, Maradona JA, Arribas JM. Acute-subacute lead poisoning. Clinical findings and comparative study of diagnostic tests. Arch Intern Med. Apr 1987;147(4):697-703. [Medline].

  11. Dietrich KN, Ware JH, Salganik M, et al. Effect of chelation therapy on the neuropsychological and behavioral development of lead-exposed children after school entry. Pediatrics. Jul 2004;114(1):19-26. [Medline].

  12. American Academy of Pediatrics. Treatment guidelines for lead exposure in children. American Academy of Pediatrics Committee on Drugs. Pediatrics. Jul 1995;96(1 Pt 1):155-60. [Medline]. [Full Text].

  13. Atre AL, Shinde PR, Shinde SN, Wadia RS, Nanivadekar AA, Vaid SJ. Pre- and posttreatment MR imaging findings in lead encephalopathy. AJNR Am J Neuroradiol. Apr 2006;27(4):902-3. [Medline].

  14. Rogan WJ, Dietrich KN, Ware JH, et al. The effect of chelation therapy with succimer on neuropsychological development in children exposed to lead. N Engl J Med. May 10 2001;344(19):1421-6. [Medline].

  15. Bellinger DC, Stiles KM, Needleman HL. Low-level lead exposure, intelligence and academic achievement: a long-term follow-up study. Pediatrics. Dec 1992;90(6):855-61. [Medline].

  16. Chen A, Dietrich KN, Ware JH, et al. IQ and blood lead from 2 to 7 years of age: are the effects in older children the residual of high blood lead concentrations in 2-year-olds?. Environ Health Perspect. May 2005;113(5):597-601. [Medline].

  17. Hornung R, Lanphear B, Dietrich K. Response to: "What is the meaning of non-linear dose-response relationships between blood lead concentration and IQ?". Neurotoxicology. Jul 2006;27(4):635. [Medline].

  18. Lanphear BP, Hornung R, Khoury J, et al. Low-level environmental lead exposure and children's intellectual function: an international pooled analysis. Environ Health Perspect. Jul 2005;113(7):894-9. [Medline].

  19. Benjamin JT, Platt C. Is universal screening for lead in children indicated? An analysis of lead results in Augusta, Georgia in 1997. J Med Assoc Ga. Dec 1999;88(4):24-6. [Medline].

  20. Finkelstein Y, Markowitz ME, Rosen JF. Low-level lead-induced neurotoxicity in children: an update on central nervous system effects. Brain Res Brain Res Rev. Jul 1998;27(2):168-76. [Medline].

  21. Friedman JA, Weinberger HL. Six children with lead poisoning. Am J Dis Child. Sep 1990;144(9):1039-44. [Medline].

  22. Gordon RA, Roberts G, Amin Z, et al. Aggressive approach in the treatment of acute lead encephalopathy with an extraordinarily high concentration of lead. Arch Pediatr Adolesc Med. Nov 1998;152(11):1100-4. [Medline].

  23. Jacob B, Ritz B, Heinrich J, et al. The effect of low-level blood lead on hematologic parameters in children. Environ Res. Feb 2000;82(2):150-9. [Medline].

  24. Johnston MV, Goldstein GW. Selective vulnerability of the developing brain to lead. Curr Opin Neurol. Dec 1998;11(6):689-93. [Medline].

  25. Klitzman S, Leighton J. Decreasing childhood lead poisoning in New York City: 1970-1998. J Urban Health. Dec 1999;76(4):542-5. [Medline].

  26. Liu X, Dietrich KN, Radcliffe J, et al. Do children with falling blood lead levels have improved cognition?. Pediatrics. Oct 2002;110(4):787-91. [Medline].

  27. Needleman HL, Schell A, Bellinger D, et al. The long-term effects of exposure to low doses of lead in childhood. An 11-year follow-up report. N Engl J Med. Jan 11 1990;322(2):83-8. [Medline].

  28. Pischik E, Kauppinen R. Lead poisoning from the beauty case: neurologic manifestations in an elderly woman. Neurology. Jul 22 2008;71(4):302; author reply 302-3. [Medline].

  29. Pueschel SM, Linakis JG, Anderson AC. Paul H. ed. Lead Poisoning in Childhood. Baltimore, MD: Brooks; 1996:1-238.

  30. Rowland AS, McKinstry RC. Lead toxicity, white matter lesions, and aging. Neurology. May 23 2006;66(10):1464-5. [Medline].

  31. Silbergeld EK. Lead poisoning: the implications of current biomedical knowledge for public policy. Md Med J. Mar 1996;45(3):209-17. [Medline].

  32. Silbergeld EK. Mechanisms of lead neurotoxicity, or looking beyond the lamppost. FASEB J. Oct 1992;6(13):3201-6. [Medline].

  33. Tang HW, Huel G, Campagna D, et al. Neurodevelopmental evaluation of 9-month-old infants exposed to low levels of lead in utero: involvement of monoamine neurotransmitters. J Appl Toxicol. May-Jun 1999;19(3):167-72. [Medline].

  34. Tong S, Baghurst PA, Sawyer MG, et al. Declining blood lead levels and changes in cognitive function during childhood: the Port Pirie Cohort Study. JAMA. Dec 9 1998;280(22):1915-9. [Medline].

[ CLOSE WINDOW ]

Further Reading

[ CLOSE WINDOW ]

Keywords

lead encephalopathy, lead poisoning, lead toxicity, plumbism, lead-based paint, lead absorption, effects of lead poisoning, lead exposure

[ CLOSE WINDOW ]

Contributor Information and Disclosures

Author

Adam K Rowden, DO, Assistant Professor of Emergency Medicine, Thomas Jefferson University; Director, Division of Toxicology, Department of Emergency Medicine, Albert Einstein Medical Center; Consulting Toxicologist, Children's Hospital of Philadelphia
Adam K Rowden, DO is a member of the following medical societies: American Academy of Emergency Medicine, American College of Emergency Physicians, American College of Medical Toxicology, American College of Osteopathic Emergency Physicians, American Osteopathic Association, and Society for Academic Emergency Medicine
Disclosure: Nothing to disclose.

Coauthor(s)

Christopher P Holstege, MD, Associate Professor of Emergency Medicine and Pediatrics, University of Virginia; Director, Division of Medical Toxicology, Center of Clinical Toxicology; Medical Director, Blue Ridge Poison Ctr, Associate Medical Toxicology Fellowship Director, VA Dept of Health
Christopher P Holstege, MD is a member of the following medical societies: American Academy of Clinical Toxicology, American Academy of Emergency Medicine, American Association for the Advancement of Science, American College of Emergency Physicians, American College of Medical Toxicology, American Medical Association, Medical Society of Virginia, Society for Academic Emergency Medicine, Society of Toxicology, and Wilderness Medical Society
Disclosure: Nothing to disclose.

J Stephen Huff, MD, Associate Professor, Emergency Medicine and Neurology, Department of Emergency Medicine, University of Virginia Health Sciences Center
J Stephen Huff, MD is a member of the following medical societies: American Academy of Emergency Medicine, American Academy of Neurology, American College of Emergency Physicians, and Society for Academic Emergency Medicine
Disclosure: Nothing to disclose.

Rika Nagakuni O'Malley, MD, Fellow, Division of Toxicology, Department of Emergency Medicine, Albert Einstein Medical Center
Disclosure: Nothing to disclose.

Medical Editor

Jonathan S Rutchik, MD, MPH, Assistant Professor, Department of Occupational and Environmental Medicine, University of California at San Francisco
Jonathan S Rutchik, MD, MPH is a member of the following medical societies: American Academy of Neurology, American Association of Neuromuscular and Electrodiagnostic Medicine, American College of Occupational and Environmental Medicine, and Society of Toxicology
Disclosure: Nothing to disclose.

Pharmacy Editor

Francisco Talavera, PharmD, PhD, Senior Pharmacy Editor, eMedicine
Disclosure: eMedicine Salary Employment

Managing Editor

Richard J Caselli, MD, Professor, Department of Neurology, Mayo Medical School, Rochester, MN; Chair, Department of Neurology, Mayo Clinic of Scottsdale
Richard J Caselli, MD is a member of the following medical societies: American Academy of Neurology, American Association of Neuromuscular and Electrodiagnostic Medicine, American Medical Association, American Neurological Association, and Sigma Xi
Disclosure: Nothing to disclose.

CME Editor

Selim R Benbadis, MD, Professor, Director of Comprehensive Epilepsy Program, Departments of Neurology and Neurosurgery, University of South Florida School of Medicine, Tampa General Hospital
Selim R Benbadis, MD is a member of the following medical societies: American Academy of Neurology, American Academy of Sleep Medicine, American Clinical Neurophysiology Society, American Epilepsy Society, and American Medical Association
Disclosure: Nothing to disclose.

Chief Editor

Tarakad S Ramachandran, MBBS, FRCP(C), FACP, Professor of Neurology, Clinical Professor of Medicine, Clinical Professor of Family Medicine, Clinical Professor of Neurosurgery, State University of New York Upstate Medical University; Chair, Department of Neurology, Crouse Irving Memorial Hospital
Tarakad S Ramachandran, MBBS, FRCP(C), FACP is a member of the following medical societies: American Academy of Neurology, American Academy of Pain Medicine, American College of Forensic Examiners, American College of International Physicians, American College of Managed Care Medicine, American College of Physicians, American Heart Association, American Stroke Association, Royal College of Physicians, Royal College of Physicians and Surgeons of Canada, Royal College of Surgeons of England, and Royal Society of Medicine
Disclosure: Abbott Labs  Honoraria Consulting; Teva Marion Honoraria Consulting; Boeringer-Ingelheim Honoraria Speaking and teaching

 
 
HONcode

We subscribe to the
HONcode principles of the
Health On the Net Foundation

All material on this website is protected by copyright, Copyright© 1994- by Medscape.
This website also contains material copyrighted by 3rd parties.

DISCLAIMER: The content of this Website is not influenced by sponsors. The site is designed primarily for use by qualified physicians and other medical professionals. The information contained herein should NOT be used as a substitute for the advice of an appropriately qualified and licensed physician or other health care provider. The information provided here is for educational and informational purposes only. In no way should it be considered as offering medical advice. Please check with a physician if you suspect you are ill.