title: Methylmalonic acidemia, cobalamin C type, presenting with cutaneous manifestations.
abstract: BACKGROUND
  Erosive dermatitis resembling the skin lesions of acrodermatitis enteropathica has been described in a number of aminoacidopathies and organic acidemias. In some, the dermatitis is a manifestation of untreated disease, while in others, including methylmalonic acidemia, skin lesions have been ascribed to nutritional deficiency due to therapeutic amino acid restrictions.
  
  
  METHODS
  We report 2 cases of methylmalonic acidemia presenting with cutaneous manifestations in the perinatal period before restrictive nutritional interventions. The cutaneous involvement consisted of cheilitis and diffuse erythema with erosions and desquamation. Methylmalonic acidemia, cobalamin C type, was subsequently diagnosed in both cases.
  
  
  CONCLUSIONS
  An erosive, desquamating dermatitis with histopathologic characteristics resembling acrodermatitis enteropathica may be a presenting sign in cobalamin C methylmalonic acidemia, even in the absence of long-standing nutritional restrictions or deficiency.
authors.affiliation: Department of Dermatology, University of California, San Francisco, USA.
authors.forename: R
authors.initials: R
authors.lastname: Howard
authors.forename: I J
authors.initials: IJ
authors.lastname: Frieden
authors.forename: D
authors.initials: D
authors.lastname: Crawford
authors.forename: T
authors.initials: T
authors.lastname: McCalmont
authors.forename: M L
authors.initials: ML
authors.lastname: Levy
authors.forename: D S
authors.initials: DS
authors.lastname: Rosenblatt
authors.forename: L
authors.initials: L
authors.lastname: Sweetman
authors.forename: S I
authors.initials: SI
authors.lastname: Goodman
authors.forename: C
authors.initials: C
authors.lastname: Ohnstad
authors.forename: K
authors.initials: K
authors.lastname: Hart
authors.forename: M
authors.initials: M
authors.lastname: Berrios
authors.forename: S
authors.initials: S
authors.lastname: Packman
mesh_terms: D000169:Acrodermatitis / Q000097:blood / Q000175:diagnosis; D000592:Amino Acid Metabolism, Inborn Errors / Q000097:blood* / Q000175:diagnosis; D001706:Biopsy; D002613:Cheilitis / Q000097:blood / Q000175:diagnosis; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D007532:Isoleucine / Q000378:metabolism*; D008764:Methylmalonic Acid / Q000097:blood*; D012867:Skin / Q000473:pathology; D012875:Skin Diseases, Metabolic / Q000097:blood* / Q000175:diagnosis; D014633:Valine / Q000378:metabolism*; D014806:Vitamin B 12 Deficiency / Q000097:blood* / Q000175:diagnosis
chemical_list: D007532:Isoleucine; D008764:Methylmalonic Acid; D014633:Valine