TY - JOUR
T1 - Muscle histopathology in upper motor neuron-dominant amyotrophic lateral sclerosis
AU - Sorarù, Gianni
AU - D'Ascenzo, Carla
AU - Nicolao, Piero
AU - Volpe, Marco
AU - Martignago, Sara
AU - Palmieri, Arianna
AU - Romeo, Vincenzo
AU - Koutsikos, Konstantinos
AU - Piccione, Francesco
AU - Cima, Valentina
AU - Pegoraro, Elena
AU - Angelini, Corrado
PY - 2008
Y1 - 2008
N2 - The distinction between primary lateral sclerosis (PLS) and amyotrophic lateral sclerosis (ALS) still remains debated. Recently, PLS patients displaying lower motor neuron (LMN) signs have been defined as 'upper motor neuron (UMN)-dominant ALS', using 'clinically pure PLS' diagnosis to those with no LMN signs. To further characterize the LMN involvement in UMN-dominant ALS we investigated the presence and the extent of neurogenic abnormalities in the skeletal muscle of patients affected with a pyramidal syndrome consistent with UMN-dominant ALS. A total of nine patients affected with UMN-dominant ALS were analysed. In all cases, muscle biopsies showed the presence of scattered or clustered atrophic angulated fibres in small groups, and a mild to moderate fibre type-grouping. Target and targetoid fibres were detected in two cases only. Three patients had a second muscle biopsy which demonstrated a roughly unchanged pattern of chronic denervation with still moderate reinnervation phenomena. This study suggests that in UMN-dominant ALS muscle denervation may be characterized by an early chronic impairment of a restricted number of LMNs. The extent rather than the presence of LMN signs may allow to categorize patients with motor neuron disease involving mainly UMN into distinct entities.
AB - The distinction between primary lateral sclerosis (PLS) and amyotrophic lateral sclerosis (ALS) still remains debated. Recently, PLS patients displaying lower motor neuron (LMN) signs have been defined as 'upper motor neuron (UMN)-dominant ALS', using 'clinically pure PLS' diagnosis to those with no LMN signs. To further characterize the LMN involvement in UMN-dominant ALS we investigated the presence and the extent of neurogenic abnormalities in the skeletal muscle of patients affected with a pyramidal syndrome consistent with UMN-dominant ALS. A total of nine patients affected with UMN-dominant ALS were analysed. In all cases, muscle biopsies showed the presence of scattered or clustered atrophic angulated fibres in small groups, and a mild to moderate fibre type-grouping. Target and targetoid fibres were detected in two cases only. Three patients had a second muscle biopsy which demonstrated a roughly unchanged pattern of chronic denervation with still moderate reinnervation phenomena. This study suggests that in UMN-dominant ALS muscle denervation may be characterized by an early chronic impairment of a restricted number of LMNs. The extent rather than the presence of LMN signs may allow to categorize patients with motor neuron disease involving mainly UMN into distinct entities.
KW - Amyotrophic lateral sclerosis
KW - Lower motor neuron
KW - Primary lateral sclerosis
KW - Skeletal muscle
KW - Upper motor neuron
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U2 - 10.1080/17482960802206801
DO - 10.1080/17482960802206801
M3 - Article
C2 - 18608096
AN - SCOPUS:52649154673
VL - 9
SP - 287
EP - 293
JO - Amyotrophic Lateral Sclerosis and Other Motor Neuron Disorders
JF - Amyotrophic Lateral Sclerosis and Other Motor Neuron Disorders
SN - 1466-0822
IS - 5
ER -