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Updated: May 9, 2026

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

Case of an infant with hepatic cirrhosis caused by mitochondrial respiratory chain disorder

Shigehiro Enkai1, Sachi Koinuma, Reiko Ito

  • 1Department of Pediatrics, Fussa Hospital, Tokyo, Japan. enkai@fussahp.jp

Pediatrics International : Official Journal of the Japan Pediatric Society
|August 6, 2013
PubMed

Insights

Mitochondrial respiratory chain disorders can cause liver dysfunction and cirrhosis in infants. Testing mitochondrial function via liver biopsy is crucial for diagnosing these rare conditions.

Area of Science:

  • Biochemistry
  • Pediatric Gastroenterology
  • Genetics

Background:

  • Mitochondrial respiratory chain disorders are rare genetic conditions affecting cellular energy production.
  • Liver dysfunction in infants can have various causes, including metabolic and genetic disorders.

Observation:

  • A 1-month-old infant presented with hepatomegaly and liver dysfunction.
  • Imaging revealed multiple liver nodules, and biopsy confirmed extremely low activity of mitochondrial respiratory chain complexes I and IV.
  • Histology was suggestive of a mitochondrial disorder, with progressive cirrhosis noted by age 5.

Findings:

  • The patient exhibited deficiencies in mitochondrial respiratory chain complexes I and IV, indicated by low enzyme activity ratios and weak bands on blue native polyacrylamide gel electrophoresis.
  • These biochemical findings, coupled with clinical and histological data, confirmed a mitochondrial respiratory chain disorder.

Implications:

  • Early diagnosis of mitochondrial respiratory chain disorders is vital for timely intervention and management.
  • Liver biopsy with mitochondrial function testing should be considered in infants with unexplained hepatitis or cirrhosis.
  • This case highlights the importance of considering mitochondrial dysfunction in pediatric liver disease.

Keywords:
chronic hepatitisinfantliver cirrhosismitochondrial respiratory chain complex I and IV deficiencymitochondrial respiratory chain disorder

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