Alternating hemiplegia of childhood: Metabolic studies in the largest European series of patients

• DOI: 10.1016/j.ejpn.2011.08.006
• Publication Date: 2011-09-26T13:16:51Z
• Authors: Carmen Fons; Jaume Campistol; Eleni Panagiotakaki; Melania Giannotta; Alexis Arzimanoglou; Giuseppe Gobbi; Brian Neville; Friedrich Ebinger; Soňa Nevšímalová; Laura Laan; Paul Casaer; Georg Spiel; Miriam Ninan; Guenter Sange; Rafael Artuch; Tsveta Schyns; Rosaria Vavassori; Dominique Poncelin
• Keywords: Adult; Male; Mitochondrial Diseases; Adolescent; Brain Diseases, Metabolic; Infant, Newborn; Infant; Hemiplegia; Middle Aged; 3. Good health; Cohort Studies; Diagnosis, Differential; Europe; Young Adult; 03 medical and health sciences; 0302 clinical medicine; Child, Preschool; Humans; Female; Child; Retrospective Studies

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.