Amyloid neuropathy simulating lower motor neuron disease.
We report a 57-year-old man with progressive symmetric weakness and fasciculation affecting the legs. Electromyography revealed fibrillations and neurogenic motor unit potentials in the leg muscles. Biopsy of a motor branch of the obturator nerve revealed axonal degeneration, loss of myelinated nerve fibers, and amyloidosis with deposits of lambda light chains. At 6-month follow-up, the patient manifested sensory and autonomic symptoms, and lambda light chains were first detected in the serum. In this case, diagnosis of amyloidosis remained elusive until motor nerve biopsy.
Department of Neurology, San Raffaele Scientific Institute, University of Milan, Italy.
A
A
Quattrini
R
R
Nemni
B
B
Sferrazza
G
G
Ricevuti
G
G
Dell'Antonio
A
A
Lazzerini
S
S
Iannaccone
D017772:Amyloid Neuropathies / Q000175:diagnosis* / Q000503:physiopathology; D001706:Biopsy; D003937:Diagnosis, Differential; D006801:Humans; D008297:Male; D008875:Middle Aged; D016472:Motor Neuron Disease / Q000175:diagnosis* / Q000503:physiopathology; D009431:Neural Conduction / Q000502:physiology