Acta Neurologica Belgica

, Volume 117, Issue 1, pp 355–357 | Cite as

Chronic negative myoclonus with hypercapnic encephalopathy

  • Yong-Bang Kim
  • Hyung-Eun Park
  • Dong-Woo Ryu
  • Woojun Kim
  • Joong-Seok KimEmail author
Letter to the Editor

Dear Editor,

“Hypercapnic encephalopathy syndrome” is a respiratory encephalopathy that is a potentially reversible condition associated with acute respiratory failure and severely decompensated respiratory hypercapnic acidosis [1]. There have been few reports of asterixis caused by acute respiratory failure and the presence of asterixis is one of the prognostic markers of acute exacerbations of chronic obstructive pulmonary disease (COPD) [2].

Here we report on a 66-year-old man with COPD accompanied by chronic negative myoclonus. The patient had been healthy prior to the sudden development of myoclonus in the forearm and trunk 4 months earlier. This symptom was evident at rest and pronounced with an out-stretched hand posture. The patient denied any significant medical history including pulmonary diseases or drug exposure.

The physical examination was normal and neurological examination revealed jerky and brisk myoclonic movements of the arms and trunk, and a negative myoclonus that...


Chronic Obstructive Pulmonary Disease Acute Respiratory Failure Video Segment Focal Seizure Hypercapnic Acidosis 
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Compliance with ethical standards

Conflict of interest

The authors have no conflicts of interest or financial support to report.

Ethical approval

The institutional review board at St. Mary’s Hospital approved this case report.

Informed consent

The patients have consented to the submission of the case report to the journal.

Supplementary material

Supplementary material 1 (WMV 10894 kb)

Supplementary material 2 (WMV 9507 kb)

Supplementary material 3 (WMV 18369 kb)


  1. 1.
    Scala R (2011) Hypercapnic encephalopathy syndrome: a new frontier for non-invasive ventilation? Respir Med 105(8):1109–1117CrossRefPubMedGoogle Scholar
  2. 2.
    Roche N, Chavaillon JM, Maurer C, Zureik M, Piquet J (2014) A clinical in-hospital prognostic score for acute exacerbations of COPD. Respir Res 15:99CrossRefPubMedPubMedCentralGoogle Scholar

Copyright information

© Belgian Neurological Society 2016

Authors and Affiliations

  1. 1.Department of Neurology, College of Medicine, Seoul St. Mary’s HospitalThe Catholic University of KoreaSeoulRepublic of Korea

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