Infantile mitochondria encephalomyopathies: report on 4 cases
O Pastoris1, M Dossena, R Scelsi
1Institute of Pharmacology, Faculty of Science, University of Pavia, Italy.
European Neurology
|January 1, 1993
Summary
Biochemical analysis revealed mitochondrial metabolism disorders and cytochrome c oxidase deficiency in children with suspected mitochondrial encephalomyopathy. Morphological changes were minimal in early stages, suggesting biochemical markers are more sensitive.
Area of Science:
- Pediatric Neurology
- Mitochondrial Diseases
- Muscle Physiology
Background:
- Mitochondrial encephalomyopathies are a group of inherited metabolic disorders.
- Early diagnosis is crucial for effective management and treatment.
- Understanding the interplay between biochemical and morphological changes is key.
Observation:
- Muscle biopsies from children with suspected mitochondrial encephalomyopathy were analyzed.
- Biochemical assays showed impaired mitochondrial metabolism, notably reduced cytochrome c oxidase activity.
- Elevated blood lactate and pyruvate levels were observed in all patients, even after glucose loading.
Findings:
- Morphological studies revealed smaller muscle fiber diameters compared to controls.
- Classic red ragged fibers and ultrastructural mitochondrial abnormalities were rare, seen in only one case.
- Focal alterations in sarcoplasmic oxidative enzyme distribution were noted in three patients.
Implications:
- Biochemical derangements in mitochondrial metabolism are prominent early indicators of mitochondriopathies.
- Morphological and ultrastructural changes may not be apparent in the early stages of these conditions.
- Biochemical findings appear more sensitive than morphological assessments for early detection.
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