Chapter 123. Polymyositis

  1. Robert P. Lisak MD, FAAN, FRCP Parker Webber Chair Professor Chair Neurologist-in-Chief Chief3,4,
  2. Daniel D. Truong MD, FAAN Head5,
  3. William M. Carroll MBBS, MD, FRACP, FRCP(E) Head6 and
  4. Roongroj Bhidayasiri MD, FRCP Director7,8
  1. Marinos C. Dalakas MD Chair Professor of Neurology Chief1,2

Published Online: 18 MAY 2010

DOI: 10.1002/9781444317008.ch123

International Neurology: A Clinical Approach

International Neurology: A Clinical Approach

How to Cite

Dalakas, M. C. (2009) Polymyositis, in International Neurology: A Clinical Approach (eds R. P. Lisak, D. D. Truong, W. M. Carroll and R. Bhidayasiri), Wiley-Blackwell, Oxford, UK. doi: 10.1002/9781444317008.ch123

Editor Information

  1. 3

    Wayne State University School of Medicine, Detroit, MI, USA

  2. 4

    Detroit Medical Center, Harper University Hospital, Detroit, MI, USA

  3. 5

    The Parkinson and Movement Disorder Institute, Memorial Neuroscience Institute, Orange Coast Memorial Medical Center, Fountain Valley, CA, USA

  4. 6

    Sir Charles Gairdner Hospital, Nedlands, Perth, Australia

  5. 7

    Chulalongkorn Comprehensive Movement Disorders Center, Chulalongkorn University Hospital, Bangkok, Thailand

  6. 8

    University of California at Los Angeles, School of Medicine, Los Angeles, CA, USA

Author Information

  1. 1

    Imperial College, London, UK

  2. 2

    Thomas Jefferson University, Philadelphia, USA

Publication History

  1. Published Online: 18 MAY 2010
  2. Published Print: 11 SEP 2009

ISBN Information

Print ISBN: 9781405157384

Online ISBN: 9781444317008



  • polymyositis (PM), three main subsets of inflammatory myopathies;
  • dermatomyositis (DM) and inclusion body myositis (IBM);
  • PM, no unique clinical features - diagnosis of exclusion;
  • PM extremely rare in childhood - diagnosis made in patients younger than 16 years;
  • HIV and HTLV-I among viruses - only ones convincingly associated with PM;
  • factors triggering T cell-mediated process in PM remaining unclear;
  • creatine kinase (CK), paralleling disease activity;
  • treatment remaining empirical, and separate - in large-scale, prospective;
  • PM natural history, unknown because steroids are applied early after diagnosis


This chapter contains sections titled:

  • Introduction

  • Clinical manifestations

  • Association conditions

  • Immunopathogenesis

  • Differential diagnosis

  • Diagnosis

  • Therapy

  • Prognosis

  • Further reading