AL amyloidosis presenting with limb girdle myopathy

Abstract

An elderly Caucasian man presented with a 10-month history of proximal myopathy and dysphagia. His serum creatine kinase (CK) was elevated at 877 U/L (normal 40-320) and electromyography confirmed a myopathic process. Blood and urine tests suggested myeloma; bone marrow examination showed 30% plasma cells and stained positive for amyloid. The muscle biopsy was initially reported as normal but in the light of the bone marrow report, the biopsy specimen was stained for amyloid, which was positive. We diagnosed systemic amyloidosis causing a myopathy and have started treatment for myeloma.

Skeletal Myopathy as the Initial Manifestation of Light Chain Multiple Myeloma

“…Only 1-2% of patients have EMD at the time of diagnosis and more than 90% of cases of EMD are diagnosed in the head and neck [1] . Skeletal myopathy, as a manifestation of EMD in the setting of MM, is very uncommon and is usually the consequence of AL amyloidosis deposition in the muscles [2,3] . Our case has several distinguishing features.…”