Isolated neck extensor myopathy: is it responsive to immunotherapy?
OBJECTIVE
To determine if isolated neck extensor myopathy (INEM) is responsive to immunosuppressive treatment.


METHODS
We retrospectively reviewed charts of patients with INEM from 2002 to 2008 to identify patients and determine the response to immunomodulatory therapy. Clinical, electrodiagnostic, histologic, and radiographic data were reviewed.


RESULTS
Four patients were identified during the study period. Three were women. The age of onset of neck extensor weakness ranged from 58 to 78 years. Serum creatine kinase levels were within normal limits in all patients. None had clinical, laboratory, or electrophysiological findings to suggest a generalized neuromuscular disorder. On electrodiagnostic studies, all patients had myopathic changes with or without irritative features in cervical paraspinal muscles. No inflammation was present on muscle biopsy from three of the patients. All patients received one or more immunosuppressive agents. Neck strength improved by 1 point or greater on the Medical Research Council scale in all subjects with a peak response observed between 3 and 6 months after treatment initiation.


CONCLUSIONS
A trial of immunosuppressive agents should be offered to patients with INEM because a subset will improve. Rigorously defined, INEM is a noninflammatory myopathy. However, a focal myositis could be missed on muscle biopsy and may explain the favorable response to treatment.
Muppidi
Srikanth
S
Department of Neurology, University of Texas Southwestern Medical Center, Dallas, TX 75390-9129, USA. srikanth.muppidi@utsouthwestern.edu
Saperstein
David S
DS
Shaibani
Aziz
A
Nations
Sharon P
SP
Vernino
Steven
S
Wolfe
Gil I
GI
D000368:Aged; D005260:Female; D006801:Humans; D007166:Immunosuppressive Agents / Q000627:therapeutic use*; D007167:Immunotherapy / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009135:Muscular Diseases / Q000188:drug therapy* / Q000276:immunology* / Q000473:pathology; D009334:Neck Muscles / Q000187:drug effects* / Q000276:immunology* / Q000473:pathology; D012189:Retrospective Studies; D016896:Treatment Outcome
D007166:Immunosuppressive Agents