Case Study McArdle Disease
McArdle disease: a case report and review
Leite A, Oliveira N, Rocha M (Modified by Kaylynn Schwamb and Michael Helton)
McArdle's Disease is a recessive inherited disorder that presents as an inability to metabolize glycogen, the storage form of glucose. This results in a variety of symptoms affecting the musculoskeletal and urinary systems, with the most common symptom being muscle fatigue. This case study adapted from Leite et al. and expanded by Kaylynn Schwamb and Michael Helton, DPT students at Bellarmine University. This disease can be well managed with a holistic and multidisciplinary approach that involves physical therapy.
This case demonstrates some of the day-to-day struggles of living with McArdle's Disease along with associated signs and symptoms of the disease. It also discusses abnormal lab values and possible physical therapy interventions and outcomes.
Subjective: A 54-year-old man presented to physical therapy with a lifelong history of fatigability that worsened on exertion. Even as a child, he had experienced difficulty going up hills and lagged behind when he went out for a walk with friends. Since his childhood, he had been labeled as “lazy” by family and friends. He consulted several doctors, who were unable to provide an explanation for his symptoms, adding to his unhappiness and resulting in depression. He presented with early fatigue complaints and contractures triggered by dynamic exercise (climbing stairs) during a visit to his mother in hospital. He described a sensation of his legs becoming “stiff like a board” after walking for a while; this symptom was relieved by rest. These symptoms were worse if he was hungry and were alleviated after meals. There were no diurnal fluctuations in symptoms. There was no neuromuscular disease in his family history. He had depression and a long history of alcohol abuse. He had been receiving long-term treatment with tianeptine, bromazepam, omeprazole, and silymarin.
Demographic Information: 54 y/o male; currently employed as a CPA
Medical Diagnosis: N/A
Co-morbidities: Obese, long history of alcohol abuse, 1 pack per day smoker
Previous care or treatment: Received physical therapy three years ago following R TKR
Self-Report Outcome Measures: Pain at rest 2/10; RPE with moderate activity 12
Physical Performance Measures: During 5 Time Sit to Stand, pt expressed fatigue following one repetition; global MMT of UE is a 4-/5, global MMT of LE is a 3+/5; ROM 50% for hamstrings, gastrocs, and hip flexors
Physical therapist referred the patient to his primary care provider for additional testing. Results were as follows.
- Results of routine blood and chemistry tests showed a creatine kinase (CK) level of 7924 U/L, a lactate dehydrogenase level of 624 U/L, and a myoglobulin level of 671 ng/mL.
- Results of tests for autoimmune disease-related antibodies such as antinuclear antibody and anti-SSA, anti-SSB, and Topo-I antibodies were negative.
- Needle electromyography findings were normal at rest but upon volunteer effort, showed a myopathic pattern characterized by reduced duration and amplitude, and increased recruitment of potential short polyphasic motor units in the biceps and deltoid muscles.
- A test of sensory nerve conduction showed normal findings.
- A muscle biopsy specimen stained for glycogen showed subsarcolemmal accumulation of “lakes” of glycogen. Results of enzyme histochemistry were completely negative for myophosphorylase, confirming the diagnosis of McArdle's disease.
- The patient returned to physical therapy after having more knowledge about his condition. He wanted to maintain independence as long as possible and be able to play with his young granddaughter.
Pt has significantly decreased aerobic capacity, decreased strength in all large muscle groups, decreased ROM in the LE, and general intolerance to exercise.
- Light stretching of the hamstrings, hip flexors, and gastrocs (30 sec X 3)
- Treadmill walking program (8 min)
- Floor transfers and weight shifting (10 X)
- Effleurage massage (10 min)
- Pt education about healthy lifestyle choices
Outcomes (PT 8 weeks)
- Pt was able to complete 5 repetitions of the 5 time sit to stand in 17 seconds.
- Pt has increased duration of treadmill training to 20 minutes.
Repeat check performed after cessation of treatment revealed a CK level of 2945 U/L. There was no myoglobinuria
Pt was discharged from therapy after reaching goals and demonstrating an active role in his disease management. He began managing his diet well per McArdle's Disease diet recommendations and lost 10 pounds throughout his 8 weeks in physical therapy.
Case adapted from “McArdle Disease: A case report and review”
- Leite A, Oliveira N, Rocha M. McArdle disease: a case report and review. International Medical Case Reports Journal. 2012.