title: Alternating hemiplegia of childhood: metabolic studies in the largest European series of patients.
abstract: Alternating hemiplegia of childhood (AHC) is a rare disorder with diagnosis based on clinical criteria, as no laboratory, neuroradiological or genetic markers are currently available. The pathogenic mechanisms are still an enigma. Some hypotheses have been proposed such as hemiplegic migraine variant, epileptic mechanism, channelopathy and mitochondrial disorder, but none of these has been confirmed. Our aim was to analyze the results of metabolic studies performed on a series of 157 European patients who fulfilled diagnostic criteria for AHC. We tried to find a common metabolic abnormality, related with AHC. We did not find significant abnormalities in basic metabolic screening, at different ages. Neurotransmitters in cerebrospinal fluid (n = 26) were normal in all of the patients. Mitochondrial respiratory chain enzyme activities were analyzed in 19 muscle biopsies; in 4 cases, different MRC enzyme deficiencies were demonstrated, ranging from mild-unspecific deficiencies to more profound and probably primary defects. Although we did not find specific metabolic markers in our series, some metabolic disorders such as pyruvate dehydrogenase deficiency, MELAS, cerebral glucose transporter defect and neurotransmitter deficiency can exhibit symptoms similar to those of AHC and need to be ruled out before a diagnosis of AHC can be established. Further studies including high-throughput diagnostic technologies seem necessary to elucidate the etiology of this severe and enigmatic disorder.
authors.affiliation: Department of Child Neurology, Sant Joan de Déu Hospital, Barcelona University (UB), CIBERER, Spain.
authors.forename: Carmen
authors.initials: C
authors.lastname: Fons
authors.forename: Jaume
authors.initials: J
authors.lastname: Campistol
authors.forename: Eleni
authors.initials: E
authors.lastname: Panagiotakaki
authors.forename: Melania
authors.initials: M
authors.lastname: Giannotta
authors.forename: Alexis
authors.initials: A
authors.lastname: Arzimanoglou
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Gobbi
authors.forename: Brian
authors.initials: B
authors.lastname: Neville
authors.forename: Friedrich
authors.initials: F
authors.lastname: Ebinger
authors.forename: Soňa
authors.initials: S
authors.lastname: Nevšímalová
authors.forename: Laura
authors.initials: L
authors.lastname: Laan
authors.forename: Paul
authors.initials: P
authors.lastname: Casaer
authors.forename: Georg
authors.initials: G
authors.lastname: Spiel
authors.forename: Miriam
authors.initials: M
authors.lastname: Ninan
authors.forename: Guenter
authors.initials: G
authors.lastname: Sange
authors.forename: Rafael
authors.initials: R
authors.lastname: Artuch
authors.forename: Tsveta
authors.initials: T
authors.lastname: Schyns
authors.forename: Rosaria
authors.initials: R
authors.lastname: Vavassori
authors.forename: Dominique
authors.initials: D
authors.lastname: Poncelin
mesh_terms: D000293:Adolescent; D000328:Adult; D001928:Brain Diseases, Metabolic / Q000175:diagnosis / Q000378:metabolism* / Q000503:physiopathology; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D003937:Diagnosis, Differential; D005060:Europe; D005260:Female; D006429:Hemiplegia / Q000175:diagnosis / Q000378:metabolism* / Q000503:physiopathology; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008875:Middle Aged; D028361:Mitochondrial Diseases / Q000175:diagnosis / Q000378:metabolism* / Q000503:physiopathology; D012189:Retrospective Studies; D055815:Young Adult