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Muscle involvement with pseudohypertrophy in systemic light chain amyloidosis: Case report
Mirela Draghici1,2, Andreea Jercan1,2, Sorina Nicoleta Badelita1
1Fundeni Clinical Institute, Bucharest, Romania.
Medicine
|December 23, 2021
Summary
Muscle pseudohypertrophy is a rare sign of light chain (AL) amyloidosis. Early consideration of muscle involvement is crucial for diagnosing AL amyloidosis, especially with unexplained muscle hypertrophy.
Area of Science:
- Neurology
- Hematology
- Rare Diseases
Background:
- Light chain (AL) amyloidosis is a plasma cell disorder characterized by amyloid deposition.
- Muscle pseudohypertrophy is an uncommon but significant manifestation of AL amyloidosis.
Observation:
- A 63-year-old woman presented with progressive weakness, macroglossia, dysphonia, cachexia, hypotension, paresthesia, and lower limb muscle hypertrophy over two years.
- Diagnostic workup revealed elevated free serum lambda light chains, Congo red-positive fat pad deposits, a myopathic pattern on electromyography, and amyloid deposits in muscle biopsy.
- The patient was diagnosed with lambda light chain AL amyloidosis involving cardiac, renal, nervous system, and skeletal muscle.
Findings:
- The patient underwent three lines of therapy over 23 months.
- Achieved very slow hematological remission.
- Experienced resolution of organ dysfunction.
Implications:
- Muscle involvement should be considered in AL amyloidosis patients presenting with unexplained muscle hypertrophy or weakness.
- Macroglossia and elevated troponin T levels (without clear cardiac involvement) can be indicators of AL amyloidosis.
- Prompt diagnosis and management of AL amyloidosis are essential for improving patient outcomes and preventing further organ damage.
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