Lab Studies:
Creatinine kinase - 205 (mildly elevated)
Lactic acid - normal
Free and total serum carnitine - within normal range
Acyl Carnitine - normal
Other Studies:
Bilateral lower limb venous Dopplers - no evidence of deep venous thrombosis
MRI lower extremities without contrast - no focal intramuscular edema or fatty atrophy of the musculature about the femur, tibia or fibula. Partially imaged tendinosis and interstitial tearing of origin of patellar tendon. Signal arising from bone is within normal limits without acute fracture.
EMG/NCS - normal NCS of motor and sensory nerves in bilateral lower limbs; concentric needle EMG of right tibialis anterior and gastrocnemius muscles show low amplitude polyphasic motor units with early recruitment suggestive of myopathic process.
Consultations:
Neuromuscular consult placed for possible muscle biopsy. Specialist suggested genetic testing for myopathies, a panel was submitted which revealed AMPD1 deficiency.
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