1043-3155 Pediatr Neurol Briefs pedneurbriefs Pediatr Neurol Briefs Pediatric Neurology Briefs Pediatr Neurol Briefs 2166-6482 1043-3155 2166-3155 Pediatric Neurology Briefs Publishers Chicago, IL, USA PNB-1-26 10.15844/pedneurbriefs-1-4-5 Degenerative and Metabolic Diseases Neurology Pediatrics Nervous System Diseases Child Development Brain Diseases Neurosurgery Child Infant Spinocerebellar Degeneration http://orcid.org/0000-0002-0173-7931 Millichap J. Gordon MD 1 2 * Division of Neurology, Children's Memorial Hospital, Chicago, IL Departments of Pediatrics and Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL Correspondence: Dr. J. Gordon Millichap, E-mail: jgmillichap@northwestern.edu 09 1987 01 08 2016 1 4 26 27 Copyright: © 1987 The Author(s) 1987 This work is licensed under the Creative Commons Attribution 4.0 International License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Mitochondrial hydroxyapatite deposits in spinocerebellar degeneration

Two children, an 8-year old boy and a 6-year old girl, with progressive ataxia, dysmetria, hypoactive or absent deep tendon reflexes, equivocal plantar response, and sensory impairments, were investigated by pathologists and neurologists at the University of Vermont, Burlington, VT, and University of Saskatchewan, Saskatoon, Canada.

 Progressive Ataxia Equivocal Plantar Response Amino Acids

Two children, an 8-year old boy and a 6-year old girl, with progressive ataxia, dysmetria, hypoactive or absent deep tendon reflexes, equivocal plantar response, and sensory impairments, were investigated by pathologists and neurologists at the University of Vermont, Burlington, VT, and University of Saskatchewan, Saskatoon, Canada. The diagnosis of SCD was established by the clinical course and laboratory tests that were normal for arylsulfatase, amino acids, phytanic acid etc.

Rectal biopsy specimens were examined ultrastructurally by electron microscope and by a laser microprobe mass analyzer (LAMMA). Clusters of acicular osmophilic inclusions in the mitochrondria of neuronal somata were consistent with crystals of calcium hydroxyapatite (CHA). The calcific nature of the deposits was confirmed by LAMMA. Similar mitochrondrial inclusions were found in 10% of smooth muscle cells but not in skeletal muscle and nerve biopsy specimens. Tissue from control subjects had no mitochrondrial acicular deposits. It has been suggested that the calcium overload may interfere with mitochondrial enzyme activity by disrupting oxidative phosphorylation. [1]

COMMENT: An abnormal oxidative phosphorylation in muscle mitochondria of patients with Freidreich’s ataxia (FA) was previously demonstrated by Stumpf DA et al [2]; mitochondrial malic enzyme activity was 10% of control level in FA fibroblasts. Also, glutamate dehydrogenase deficiency has been noted in cultured skin fibroblasts and leukocyte homogenates of patients with spinocerebellar syndrome [3]. These studies and the present report may eventually lead to carrier detection and possible specific therapies for spinocerebellar degenerative disease.

 Munoz DG Emery ES 3rd Highland RA Mitochondrial hydroxyapatite deposits in spinocerebellar degeneration Ann Neurol 1987 Aug 22 2 258 63 2821875 10.1002/ana.410220211 Stumpf DA Parks JK Eguren LA Haas R Friedreich ataxia: III. Mitochondrial malic enzyme deficiency Neurology 1982 Mar 32 3 221 7 7199631 10.1212/WNL.32.3.221 Plaitakis A Nicklas WJ Desnick RJ Glutamate dehydrogenase deficiency in three patients with spinocerebellar syndrome Ann Neurol 1980 Apr 7 4 297 303 7377755 10.1002/ana.410070403