Abstract | BACKGROUND:
McArdle disease is a common metabolic disorder characterized by marked exercise intolerance, premature fatigue during exertion, myalgia, and cramps. Despite the wide knowledge of the molecular basis of McArdle disease, few studies have used a physiological approach or explored the possibility of improving the exercise capacity of these patients. OBJECTIVES: To describe 3 unrelated patients with McArdle disease with a novel mutation in the PYGM gene and to assess the physical capacity in 1 of them. DESIGN: Using molecular genetic approaches, we identified the underlying molecular defect in 3 patients with McArdle disease. Physical performance was evaluated in 1 patient by means of an exercise tolerance test on a bicycle ergometer. SETTING: Two university hospitals. Exercise physiology studies were performed in a university department. Patients The 3 patients showed common features of McArdle disease. They were definitively diagnosed by histochemistry, biochemistry, or molecular genetic analysis. RESULTS: All of the 3 patients were genetic compounds for the common Arg50Stop mutation and a novel c.13_14delCT mutation in the PYGM gene. The peak oxygen uptake (VO(2peak)) of the patient who performed the exercise test was only 20.2 mL x kg(-1) x min(-1). CONCLUSIONS: Together with the novel mutation, there is a markedly decreased exercise capacity in a patient with McArdle disease, which could account for the profound alteration in the capacity for performing normal activities of daily living in this subpopulation.
|
Authors | Juan C Rubio, Alejandro Lucia, Israel Fernández-Cadenas, Ana Cabello, Alberto Blázquez, Josep Gámez, Antoni L Andreu, Miguel A Martín, Joaquin Arenas |
Journal | Archives of neurology
(Arch Neurol)
Vol. 63
Issue 12
Pg. 1782-4
(Dec 2006)
ISSN: 0003-9942 [Print] United States |
PMID | 17172620
(Publication Type: Case Reports, Journal Article, Research Support, Non-U.S. Gov't)
|
Chemical References |
|
Topics |
- Adult
- Anaerobic Threshold
(physiology)
- Electrocardiography
- Exercise Test
- Exercise Tolerance
(physiology)
- Female
- Glycogen Phosphorylase
(genetics)
- Glycogen Storage Disease Type V
(genetics)
- Heart Rate
(physiology)
- Humans
- Mutation
(physiology)
- Oxygen Consumption
(physiology)
- Reverse Transcriptase Polymerase Chain Reaction
|