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Published on: March 4, 2014
Permanent muscle weakness in McArdle disease.
Aleksandra A Nadaj-Pakleza1, Carlo M Vincitorio, Pascal Laforêt
1Institute of Myology, Pitié-Salpêtrière Hospital, 47-83, Boulevard de l'Hôpital, 75651 Paris Cedex 13, France. anadpak@gmail.com
Muscle & Nerve
|August 12, 2009
Summary
McArdle disease, a muscle glycogenosis, can cause permanent weakness, especially after age 40. This study details the clinical and genetic features of fixed muscle weakness in affected individuals.
Area of Science:
- Neurology
- Genetics
- Metabolic Disorders
Background:
- McArdle disease is an autosomal recessive muscle glycogenosis.
- Typically presents with exercise-induced symptoms.
- Permanent muscle weakness can occur, particularly later in life.
Purpose of the Study:
- To investigate the clinical and genetic characteristics of fixed muscle weakness in McArdle disease.
- To identify patterns and prevalence of permanent weakness in a cohort of McArdle patients.
Main Methods:
- Analysis of clinical data from 80 McArdle patients.
- Muscle biopsy and genetic investigations for diagnosis confirmation.
- Assessment of muscle weakness patterns and fatty infiltration via CT scans.
Main Results:
- Nine out of 80 patients exhibited permanent muscle weakness.
- Two patterns observed: proximal/symmetric (5 patients) and asymmetric mimicking FSHD (4 patients).
- Fatty infiltration noted in shoulder and pelvic girdle muscles; no clear genotype-severity correlation.
Conclusions:
- Permanent muscle weakness affects a subset of McArdle disease patients, often appearing after age 40.
- Weakness can present with distinct patterns, including proximal and FSHD-like presentations.
- Further research may elucidate the mechanisms behind fixed weakness in McArdle disease.
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