Anti-PL7 antisynthetase syndrome under interferon therapy

Joint Bone Spine. 2011 Jan;78(1):94-7. doi: 10.1016/j.jbspin.2010.07.012. Epub 2010 Sep 18.


A 62-year-old woman with a past history of chronic hepatitis C virus infection presented an atypical predominantly painful polymyositis following a flu-like syndrome, persisting despite the withdrawal of PEG-interferon alpha-2b therapy. Clinical assessment, then immunological, electrophysiological and iconographic investigations including myositis antibodies, electromyography, pulmonary functions assessment and thoracic CT-scan found respectively "mechanic hands", arthralgia, presence of antisynthetase anti-PL7 antibody, typical myographic features of hip and shoulder girdles involvement, pulmonary fibrosis and restrictive syndrome features. A deltoid muscle biopsy revealed an unclassified myositis getting closer to anti-J0-1 and connective tissue disease associated myositis featuring: some components of polymyositis, dermatomyositis, and the following peculiar pathological aspects: noncaseous granulomatous infiltrate, endomysial microangiopathy and vascular and sarcolemic deposition of complement membrane attack complex. The diagnosis of interferon induced anti-PL7 antisynthetase syndrome with microangiopathic and granulomatous overlap myositis was retained. A treatment associating intravenous immunoglobulin and moderate tapered oral corticosteroids allowed a complete long-term resolution of myositis and a clear improvement of pulmonary involvement. This case points out the wide range of interferon alpha-associated disorders and call for a precise and detailed immunopathological analysis of myositis, instead of the usual vague classification as idiopathic polymyositis or dermatomyositis about antisynthetase syndrome.

Publication types

  • Case Reports

MeSH terms

  • Antiviral Agents / adverse effects*
  • Autoantibodies / immunology
  • Female
  • Hepatitis C, Chronic / drug therapy*
  • Hepatitis C, Chronic / immunology
  • Humans
  • Interferon alpha-2
  • Interferon-alpha / adverse effects*
  • Middle Aged
  • Myositis / chemically induced
  • Myositis / immunology
  • Polyethylene Glycols / adverse effects*
  • Recombinant Proteins
  • Threonine-tRNA Ligase / immunology*


  • Antiviral Agents
  • Autoantibodies
  • Interferon alpha-2
  • Interferon-alpha
  • Recombinant Proteins
  • Polyethylene Glycols
  • Threonine-tRNA Ligase
  • peginterferon alfa-2b

Supplementary concepts

  • Antisynthetase syndrome