title: Malonic aciduria: long-term follow-up of new patients detected by newborn screening.
abstract: Malonic aciduria is an extremely rare autosomal recessive inborn error of metabolism. We present clinical, biochemical and genetic information for several years of follow-up of new malonic aciduria patients who were diagnosed by newborn screening. These data are discussed with regard to treatment options and possible diagnostic pitfalls. The cases presented here show that the course of malonic aciduria is unpredictable and can even significantly differ in two siblings harbouring identical mutations. Early treatment can lead to the rapid improvement of cardiomyopathy in the course of malonic aciduria. Biochemical parameters seem to be variable and can intermittently be undetectable in the blood or urine samples of affected patients. Therefore, confirmatory tests following a positive newborn screening should be taken with caution and include both malonyl carnitine detection in dried blood spots and urinary organic acid analysis as initial measures.
  
  
  CONCLUSIONS
  Patients with a suspected or confirmed diagnosis of malonic aciduria should undergo thorough diagnostic procedures and be regularly screened for complications such as cardiomyopathy even when they are asymptomatic in order to ensure early therapy of treatable complications.
authors.affiliation: Department of General Pediatrics, Neonatology and Pediatric Cardiology, University Children's Hospital Duesseldorf, Heinrich-Heine-University, Moorenstr. 5, 40225, Duesseldorf, Germany, Fabian.Baertling@med.uni-duesseldorf.de.
authors.forename: Fabian
authors.initials: F
authors.lastname: Baertling
authors.forename: Ertan
authors.initials: E
authors.lastname: Mayatepek
authors.forename: Eva
authors.initials: E
authors.lastname: Thimm
authors.forename: Andrea
authors.initials: A
authors.lastname: Schlune
authors.forename: Alexander
authors.initials: A
authors.lastname: Kovacevic
authors.forename: Felix
authors.initials: F
authors.lastname: Distelmaier
authors.forename: Gajja S
authors.initials: GS
authors.lastname: Salomons
authors.forename: Thomas
authors.initials: T
authors.lastname: Meissner
mesh_terms: D002262:Carboxy-Lyases / Q000172:deficiency*; D002648:Child; D003937:Diagnosis, Differential; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008316:Malonyl Coenzyme A; D008661:Metabolism, Inborn Errors / Q000175:diagnosis*; D008764:Methylmalonic Acid; D015997:Neonatal Screening / Q000379:methods*; D035781:Siblings; D013997:Time Factors
chemical_list: D008316:Malonyl Coenzyme A; D008764:Methylmalonic Acid; D002262:Carboxy-Lyases