Sporadic inclusion body myositis misdiagnosed as idiopathic granulomatous myositis

Neuromuscul Disord. 2016 Nov;26(11):741-743. doi: 10.1016/j.nmd.2016.09.003. Epub 2016 Sep 13.

Abstract

We present a case of a 65-year-old woman who was previously diagnosed with idiopathic granulomatous myositis and treated with immunosuppressive therapy for the next 10 years before a clinical diagnosis of inclusion body myositis was made. A review of the previously performed muscle biopsy showed most of the cardinal myopathologic features of sporadic inclusion body myositis, in addition to the granuloma. Her clinical course was strongly suggestive of inclusion body myositis with selective asymmetric weakness of forearm flexor muscles and quadriceps. This report highlights the importance of correlating clinical picture with muscle pathology changes along with judicious use of magnetic resonance imaging and serological studies to establish a definite diagnosis.

Keywords: Granulomatous myositis; Inclusion body myositis; NT5C1A antibody; Sarcoidosis.

Publication types

  • Case Reports

MeSH terms

  • Aged
  • Biomarkers / blood
  • Diagnosis, Differential
  • Diagnostic Errors
  • Disease Progression
  • Female
  • Humans
  • Immunosuppressive Agents / therapeutic use
  • Methotrexate / therapeutic use
  • Muscle, Skeletal / diagnostic imaging*
  • Muscle, Skeletal / pathology*
  • Muscle, Skeletal / physiopathology
  • Myositis, Inclusion Body / diagnosis*
  • Myositis, Inclusion Body / drug therapy
  • Myositis, Inclusion Body / pathology
  • Myositis, Inclusion Body / physiopathology

Substances

  • Biomarkers
  • Immunosuppressive Agents
  • Methotrexate