title: A mitochondrial DNA deletion presenting with corneal clouding and severe Fanconi syndrome.
abstract: BACKGROUND
  Mitochondrial cytopathies are a diverse group of disorders characterized by impaired mitochondrial energy production. Disease manifestations are protean and may include seemingly disparate findings.
  
  
  METHODS
  Here we report a 5-year-old girl with the uncommon pairing of bilateral corneal dystrophy requiring corneal transplantation and severe Fanconi syndrome recalcitrant to oral bicarbonate therapy necessitating intravenous supplementation. Etiological work-up included qualitative urine organic acid testing, which demonstrated abnormalities in lactate, pyruvate, and ketoacids suggestive of a mitochondrial etiology. Confirmatory genetic testing in blood leukocytes revealed a large, novel, heteroplasmic, de novo mitochondrial DNA deletion at nt 8648-16072.
  
  
  CONCLUSIONS
  The finding of Fanconi syndrome with disease processes in other, seemingly unrelated, organ systems should raise clinical suspicion for mitochondrial disease. Early assessment of urine organic acids in the etiological work-up of Fanconi syndrome may assist in the identification of respiratory chain disorders.
authors.affiliation: Women and Children's Hospital of Buffalo, Division of Pediatric Nephrology, 219 Bryant Street, Buffalo, NY 14222, USA. joycelee@buffalo.edu
authors.forename: Joyce J
authors.initials: JJ
authors.lastname: Lee
authors.forename: Laura M
authors.initials: LM
authors.lastname: Tripi
authors.forename: Richard W
authors.initials: RW
authors.lastname: Erbe
authors.forename: Sudha
authors.initials: S
authors.lastname: Garimella-Krovi
authors.forename: James E
authors.initials: JE
authors.lastname: Springate
mesh_terms: D000137:Acid-Base Imbalance / Q000209:etiology; D000138:Acidosis / Q000150:complications; D001639:Bicarbonates / Q000627:therapeutic use; D002675:Child, Preschool; D003318:Corneal Opacity / Q000209:etiology* / Q000235:genetics*; D004272:DNA, Mitochondrial / Q000235:genetics*; D004351:Drug Resistance; D005198:Fanconi Syndrome / Q000150:complications* / Q000235:genetics*; D005260:Female; D006319:Hearing Loss, Sensorineural / Q000209:etiology; D006801:Humans; D007677:Kidney Function Tests; D028361:Mitochondrial Diseases / Q000150:complications* / Q000235:genetics*; D020795:Photophobia / Q000209:etiology; D017384:Sequence Deletion; D015431:Weight Loss
chemical_list: D001639:Bicarbonates; D004272:DNA, Mitochondrial