title: Case report: a metabolic disorder presenting as pediatric manganism.
abstract: BACKGROUND
  Manganese is a trace element, essential for physiologic functioning but neurotoxic at high doses. Common exposure sources include dietary intake as well as drinking water in some regions; toxicity is most often associated with inhalation exposures in occupational settings. In this article we describe the investigation of a pediatric case of manganism using both clinical and environmental assessment methods.
  
  
  METHODS
  A previously healthy 6-year-old child presented with severe Mn neurotoxicity, iron deficiency, and elevated cobalt levels. Immediate and selected extended family members had elevated plasma Mn but remained asymptomatic. An exposure assessment identified seasonal ingestion exposures to Mn at the family's summer cottage; these were common to the four immediate family members. Well water used for drinking and cooking exceeded recommended guidelines, and foods high in Mn predominated in their diet. No inhalation exposures were identified. Only pica was unique to the patient.
  
  
  CONCLUSIONS
  The combined evidence of the environmental assessment and biomonitoring of blood Mn levels supported a seasonal ingestion exposure source; this alone was insufficient to explain the toxicity because the patient's 7-year-old sibling was asymptomatic with almost identical exposures (except pica). A metabolic disorder involving divalent metals (Mn, Fe, and Co) interacting with environmental exposures is the most likely explanation.
  
  
  CONCLUSIONS
  This case report adds to the emerging body of evidence linking neurologic effects to ingestion Mn exposure.
authors: Canadian Field Epidemiology Program, Ottawa, Ontario, Canada. vanitasahni@hotmail.com
authors: Vanita
authors: V
authors: Sahni
authors: Yves
authors: Y
authors: Léger
authors: Linda
authors: L
authors: Panaro
authors: Mark
authors: M
authors: Allen
authors: Scott
authors: S
authors: Giffin
authors: Diane
authors: D
authors: Fury
authors: Nadine
authors: N
authors: Hamm
mesh_terms: D002648:Child; D004912:Erythrocytes; D005260:Female; D005293:Ferritins / Q000097:blood; D006801:Humans; D008345:Manganese / Q000097:blood; D020149:Manganese Poisoning / Q000473:pathology*; D008659:Metabolic Diseases / Q000473:pathology*; D013997:Time Factors
chemical_list: D008345:Manganese; D005293:Ferritins