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A 1-year-old infant with McArdle disease associated with hyper-creatine kinase-emia during febrile episodes

Yasushi Ito1, Kayoko Saito, Keiko Shishikura

  • 1Department of Pediatrics, Tokyo Women's Medical University, School of Medicine, 8-1 Kawada-cho, Shinjuku-ku, Tokyo 162-8666, Japan. ymitoh@cf6.so-net.ne.jp

Brain & Development
|August 9, 2003
PubMed

Insights

McArdle disease, a rare glycogen storage disorder, can manifest in infancy with elevated creatine kinase (CK) during fever. Early diagnosis is crucial, even with subtle muscle biopsy findings.

Area of Science:

  • Biochemistry
  • Pediatric Neurology
  • Genetics

Background:

  • McArdle disease (glycogen storage disease type V) is a rare inherited metabolic disorder affecting skeletal muscle.
  • It results from a deficiency in muscle glycogen phosphorylase, impairing glycogen breakdown for energy.
  • Diagnosis in early infancy is uncommon, with typical presentations in adolescence or adulthood.

Observation:

  • A 14-month-old girl presented with recurrent hyper-creatine kinase (CK)-emia during febrile episodes.
  • Mild hypotonia was noted, but other physical and neurological examinations were normal.
  • Serum CK levels normalized when afebrile or at rest.

Findings:

  • Muscle biopsy revealed glycogen storage and a complete absence of phosphorylase activity.
  • Histochemical and biochemical analyses confirmed the diagnosis of McArdle disease.
  • This case represents an early-onset presentation with distinct clinical and biopsy findings compared to typical adult cases.

Implications:

  • Transient hyper-CKemia in infants, particularly during fever, should prompt consideration of McArdle disease.
  • The diagnostic criteria for infantile McArdle disease may differ from adult presentations, requiring awareness of subtle biopsy findings.
  • This case highlights the importance of considering rare metabolic myopathies in pediatric hyper-CKemia, even in the absence of significant muscle pathology.

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