OBJECTIVE: To determine the occurrence of residual loss of peripheral nerve axons by motor unit number estimation (MUNE) and conventional nerve conduction studies (NCS) in patients with and without severe fatigue. METHODS: Thirty-nine patients at a median of 8 years (range 1-23 years) after diagnosis of Guillain-Barré syndrome were neurologically examined and divided in 2 subgroups based on the presence of severe fatigue (defined as a fatigue severity score ≥5). All patients were investigated with standard NCS and MUNE. Normal values for MUNE were collected in 14 healthy controls. RESULTS: MUNE of the thenar muscles was lower in the 15 patients with severe fatigue (median 125, interquartile range 65-141) compared with the 24 patients without severe fatigue (median 258, interquartile range 120-345) (p = 0.002). In the healthy controls, MUNE was 358 (245-416). Severe fatigue was also related to lower sensory nerve action potential amplitude of the median (p = 0.01) and ulnar nerve (p = 0.03). The 2 subgroups did not differ regarding neurologic deficits, disability, and the remaining conventional motor NCS. CONCLUSION: This study demonstrates that severe fatigue after Guillain-Barré syndrome is related to more pronounced axonal loss, represented by lower MUNEs and lower sensory nerve action potentials.
OBJECTIVE: To determine the occurrence of residual loss of peripheral nerve axons by motor unit number estimation (MUNE) and conventional nerve conduction studies (NCS) in patients with and without severe fatigue. METHODS: Thirty-nine patients at a median of 8 years (range 1-23 years) after diagnosis of Guillain-Barré syndrome were neurologically examined and divided in 2 subgroups based on the presence of severe fatigue (defined as a fatigue severity score ≥5). All patients were investigated with standard NCS and MUNE. Normal values for MUNE were collected in 14 healthy controls. RESULTS: MUNE of the thenar muscles was lower in the 15 patients with severe fatigue (median 125, interquartile range 65-141) compared with the 24 patients without severe fatigue (median 258, interquartile range 120-345) (p = 0.002). In the healthy controls, MUNE was 358 (245-416). Severe fatigue was also related to lower sensory nerve action potential amplitude of the median (p = 0.01) and ulnar nerve (p = 0.03). The 2 subgroups did not differ regarding neurologic deficits, disability, and the remaining conventional motor NCS. CONCLUSION: This study demonstrates that severe fatigue after Guillain-Barré syndrome is related to more pronounced axonal loss, represented by lower MUNEs and lower sensory nerve action potentials.
Authors: Nicola Latronico; Margaret Herridge; Ramona O Hopkins; Derek Angus; Nicholas Hart; Greet Hermans; Theodore Iwashyna; Yaseen Arabi; Giuseppe Citerio; E. Wesley Ely; Jesse Hall; Sangeeta Mehta; Kathleen Puntillo; Johannes Van den Hoeven; Hannah Wunsch; Deborah Cook; Claudia Dos Santos; Gordon Rubenfeld; Jean-Louis Vincent; Greet Van den Berghe; Elie Azoulay; Dale M Needham Journal: Intensive Care Med Date: 2017-03-13 Impact factor: 17.440