title: Mucopolysaccharidosis Type IIIA presents as a variant of Klüver-Bucy syndrome.
abstract: Mucopolysaccharidosis Type IIIA (MPS IIIA) is a neurodegenerative disease with behavioral symptoms unique among the mucopolysaccharidoses. Children with MPS IIIA reportedly mouth things, explore novel environments almost continuously, disregard danger, and empathize/socialize and comply less with parents. These characteristics resemble Klüver-Bucy syndrome (K-Bs). To test the K-Bs hypothesis, 30 children with MPS IIIA were compared to 8 "posttransplant" mucopolysaccharidosis Type IH patients in an experimental "risk room." The room contained attractive and mildly frightening objects, exposure to a 92-dB startle noise triggered by contact with an attractive toy, mother's return after a brief absence, and compliance with her cleanup directive. Children with MPS IIIA: (a) left mother sooner, (b) wandered more, (c) were more likely to approach frightening objects, (d) were less likely to respond to loud noise with whole body startle, (e) were less likely to avoid the toy associated with the startle noise, (f) interacted less with mother upon her return, and (g) complied less with her cleanup command. K-Bs is associated with loss of amygdala function. Brain magnetic resonance imaging (MRI) of a subset of the children with MPS IIIA showed volume loss that was greater in the amygdala than in the hippocampus; only amygdala loss correlated with reduced fearfulness. MPS IIIA may be the first identified pediatric disease presenting systematically as a K-Bs variant. If validated by further studies, the K-Bs hypothesis of MPS IIIA would provide important clinical and theoretical information for the guidance of families as well as markers for natural disease progression and treatment effects.
authors.affiliation: Department of Pediatrics and Neurology, Division of Biostatistics, Minneapolis, MN, USA. poteg001@umn.edu
authors.forename: Michael
authors.initials: M
authors.lastname: Potegal
authors.forename: Brianna
authors.initials: B
authors.lastname: Yund
authors.forename: Kyle
authors.initials: K
authors.lastname: Rudser
authors.forename: Alia
authors.initials: A
authors.lastname: Ahmed
authors.forename: Kate
authors.initials: K
authors.lastname: Delaney
authors.forename: Igor
authors.initials: I
authors.lastname: Nestrasil
authors.forename: Chester B
authors.initials: CB
authors.lastname: Whitley
authors.forename: Elsa G
authors.initials: EG
authors.lastname: Shapiro
mesh_terms: D000293:Adolescent; D000679:Amygdala / Q000473:pathology / Q000503:physiopathology; D001245:Association Learning / Q000502:physiology; D001362:Avoidance Learning / Q000502:physiology; D001933:Brain Stem / Q000473:pathology / Q000503:physiopathology; D002540:Cerebral Cortex / Q000473:pathology / Q000503:physiopathology; D002648:Child; D002675:Child, Preschool; D003299:Cooperative Behavior; D003937:Diagnosis, Differential; D018450:Disease Progression; D016057:Evoked Potentials, Auditory, Brain Stem / Q000502:physiology; D005106:Exploratory Behavior / Q000502:physiology; D005239:Fear / Q000502:physiology / Q000523:psychology; D005260:Female; D006624:Hippocampus / Q000473:pathology / Q000503:physiopathology; D006801:Humans; D020232:Kluver-Bucy Syndrome / Q000175:diagnosis* / Q000503:physiopathology / Q000523:psychology; D008279:Magnetic Resonance Imaging; D008297:Male; D009084:Mucopolysaccharidosis III / Q000175:diagnosis* / Q000503:physiopathology / Q000523:psychology; D009769:Object Attachment; D013216:Reflex, Startle / Q000502:physiology; D012931:Social Environment