title: Persistent 5-oxoprolinuria with normal glutathione synthase and 5-oxoprolinase activities.
abstract: 5-Oxoprolinuria is primarily associated with inborn errors of the gamma-glutamyl cycle. In addition, transient 5-oxoprolinuria has been reported to occur in a variety of conditions, such as prematurity and malnutrition, and during medication. We report an unusual case of permanent 5-oxoprolinuria. The patient presented 3 days after birth with acidosis, and metabolic screening revealed massive excretion of 5-oxoproline. Following recovery, growth and psychomotor development were normal, but 5-oxoprolinuria persisted. Primary defects in the gamma-glutamyl cycle were ruled out since glutathione synthase and 5-oxoprolinase activities were normal. All known secondary causes of 5-oxoprolinuria were also excluded, leaving the basis of the permanent 5-oxoprolinuria in this patient unresolved.
authors.affiliation: Metabolic Diseases Laboratory, Leiden University Medical Centre, The Netherlands.
authors.forename: G J G
authors.initials: GJ
authors.lastname: Ruijter
authors.forename: P E C
authors.initials: PE
authors.lastname: Mourad-Baars
authors.forename: E
authors.initials: E
authors.lastname: Ristoff
authors.forename: W
authors.initials: W
authors.lastname: Onkenhout
authors.forename: B J H M
authors.initials: BJ
authors.lastname: Poorthuis
mesh_terms: D002648:Child; D005981:Glutathione Synthase / Q000378:metabolism*; D006801:Humans; D008297:Male; D011752:Pyroglutamate Hydrolase / Q000378:metabolism*; D011761:Pyrrolidonecarboxylic Acid / Q000652:urine*
chemical_list: D011752:Pyroglutamate Hydrolase; D005981:Glutathione Synthase; D011761:Pyrrolidonecarboxylic Acid