Treatment with dimercaptosuccinic acid (DMSA), an oral chelation agent, was linked to reductions in the amount of lead in blood in young children in Zamfara State, Nigeria following environmental lead contamination, according to a study by Jane Greig and colleagues from Médecins Sans Frontières (MSF) published in this week's PLOS Medicine.
The researchers report findings from an MSF program initiated in May 2010 to reduce lead poisoning in children following widespread environmental lead contamination due to gold mining in Zamfara State, Nigeria, leading to the death of an estimated 400 young children in the 3 months before chelation therapy was provided. The analysis included 3180 courses of DSMA chelation therapy administered between 1 June 2010 and 30 June 2011 to 1,156 children ≤5 y of age who had measurements of venous blood lead levels before and after each course of DMSA. The researchers found that, on average, treatment with DSMA was associated with a reduction in venous blood lead levels to 74.5% of the level at the start of the DMSA course. Nine of these 1,156 children died during the period studied, with lead poisoning likely involved in three of these deaths. The researchers report that no clinically severe adverse effects related to DMSA were seen during the study period, and no laboratory findings were recorded that required treatment discontinuation.
While the findings cannot be used to reach any definitive conclusions about the effectiveness or safety of oral DMSA as a treatment for lead poisoning in young children, blood lead levels decreased and the number of deaths was substantially reduced after the program was initiated.
The authors say: "This experience with basic supportive care and chelation in a large paediatric cohort adds significantly to the evidence base for clinical management of epidemic lead poisoning, particularly in resource-poor settings."
Funding: This study was funded as part of MSF operations. Lundbeck donated some DMSA, but had no role in the treatment programme or in study design, data collection and analysis, decision to publish, or preparation of the manuscript. The findings and conclusions in this presentation have not been formally disseminated by the Centers for Disease Control and Prevention/the Agency for Toxic Substances and Disease Registry and should not be construed to represent any agency determination or policy.
Competing Interests: The authors have declared that no competing interests exist.
Citation: Thurtle N, Greig J, Cooney L, Amitai Y, Ariti C, et al. (2014) Description of 3,180 Courses of Chelation with Dimercaptosuccinic Acid in Children #5 y with Severe Lead Poisoning in Zamfara, Northern Nigeria: A Retrospective Analysis of Programme Data. PLoS Med 11(10): pmed.1001739. doi:10.1371/journal.pmed.1001739
Médecins Sans Frontières, HOLLAND
Médecins Sans Frontières, UNITED KINGDOM
Bar Ilan University, ISRAEL
London School of Hygiene & Tropical Medicine, UNITED KINGDOM
National Center for Environmental Health, Centers for Disease Control and Prevention, USA
University of Colorado School of Medicine, USA
Federal Ministry of Health, NIGERIA
Federal Ministry of Communication Technology, NIGERIA
Guy's and St. Thomas' NHS Foundation Trust, UNITED KINGDOM
Médecins Sans Frontières