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Pure quadriceps myopathy in two sisters
1Department of Neurology, Pietarsaari Hospital, Pietarsaari, Finland. ibrahim.mahjneh@vshp.fi
European Journal of Neurology
|June 26, 2003
Summary
This study followed two sisters with quadriceps myopathy (QM), finding pure QM with likely autosomal recessive inheritance. Their symptoms involved thigh weakness and vasti muscles, with normal lab results and biopsies.
Area of Science:
- Neurology
- Genetics
- Muscle Diseases
Background:
- Quadriceps myopathy (QM) is a rare muscle disorder characterized by progressive weakness in the thigh muscles.
- Understanding the genetic basis and clinical presentation of QM is crucial for diagnosis and management.
Observation:
- A longitudinal study tracked two sisters diagnosed with quadriceps myopathy over an 18-21 year period.
- Onset of symptoms, including thigh weakness, occurred in the fourth decade of life.
- Clinical examination revealed isolated involvement of the vasti muscles.
Findings:
- Despite myopathic features on muscle biopsy and electromyography (EMG), creatine kinase (CK) levels remained normal.
- Immunocytochemical analysis showed normal membrane protein expression, ruling out known muscle pathologies with leading quadriceps involvement.
- The clinical and laboratory findings support a diagnosis of pure quadriceps myopathy.
Implications:
- The probable autosomal recessive inheritance pattern suggested in this case requires further investigation in larger cohorts.
- This case highlights the importance of comprehensive diagnostic approaches for rare myopathies.
- Further research into the specific genetic mutations underlying pure quadriceps myopathy is warranted.
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