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Visualization of Mitochondrial Respiratory Function using Cytochrome C Oxidase / Succinate Dehydrogenase (COX/SDH) Double-labeling Histochemistry
06:53

Visualization of Mitochondrial Respiratory Function using Cytochrome C Oxidase / Succinate Dehydrogenase (COX/SDH) Double-labeling Histochemistry

Published on: November 23, 2011

Benign infantile mitochondrial myopathy due to reversible cytochrome c oxidase deficiency

S DiMauro, J F Nicholson, A P Hays

    Annals of Neurology
    |August 1, 1983
    PubMed

    Insights

    This study describes a rare case of reversible cytochrome c oxidase deficiency in an infant. The infant showed significant improvement, with enzyme activity normalizing over time.

    Area of Science:

    • Biochemistry
    • Pediatrics
    • Mitochondrial Diseases

    Background:

    • Cytochrome c oxidase (COX) deficiency is a severe mitochondrial disorder.
    • The infantile form is typically fatal, presenting with profound weakness and lactic acidosis.

    Observation:

    • A 2-week-old infant presented with severe hypotonia, macroglossia, and lactic acidosis.
    • Muscle biopsies revealed mitochondrial abnormalities and severely reduced COX activity.
    • The infant demonstrated remarkable spontaneous clinical and biochemical recovery by 36 months.

    Findings:

    • Muscle biopsy and biochemical analyses confirmed an isolated COX deficiency.
    • Histochemical COX staining and enzyme activity progressively normalized.
    • This contrasts with the fatal infantile form, suggesting a reversible enzyme defect.

    Implications:

    • This case highlights a potentially reversible form of COX deficiency.
    • Understanding the biochemical basis of this reversibility is crucial.
    • Further research may lead to novel therapeutic strategies for mitochondrial disorders.

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