Positive troponin T without cardiac involvement in inclusion body myositis

Hum Pathol. 2005 Aug;36(8):917-21. doi: 10.1016/j.humpath.2005.06.009.

Abstract

Cardiac troponin T (cTnT) is considered as a specific marker for acute myocardial infarction. Here, we present a case with elevated cTnT, determined by a third-generation assay, without signs of a myocardial lesion. Routine investigation of a 66-year-old female patient with indolent B-cell lymphoma revealed increased serum levels of creatine kinase (CK), MB fraction of CK (CK-MB), and cTnT, although she did not complain of cardiac symptoms. Electrocardiographic monitoring, echocardiography, magnetic resonance computed angiography, and percutaneous coronary angiography excluded myocardial damage. However, the close follow-up showed a steady increase of CK-MB and cTnT levels and gradual development of weakness in both thighs. A biopsy of the right quadriceps muscle led to the diagnosis of inclusion body myositis. In contrast to cTnT, cardiac troponin I could not be detected retrospectively in any of her serum samples. These results demonstrate for the first time that cTnT is elevated in patients with inclusion body myositis.

Publication types

  • Case Reports

MeSH terms

  • Aged
  • Biomarkers / blood
  • Creatine Kinase / blood
  • Diagnosis, Differential
  • Female
  • Humans
  • Lymphoma, B-Cell / complications
  • Muscle, Skeletal / pathology*
  • Myocardium / pathology*
  • Myositis, Inclusion Body / blood*
  • Myositis, Inclusion Body / complications
  • Troponin T / blood*

Substances

  • Biomarkers
  • Troponin T
  • Creatine Kinase