Chloroquine-and Hydroxychloroquine-Induced Cardiomyopathy: A Case Report and Brief Literature Review

Urooba Nadeem, Muhammad Raafey, Gene Kim, Jerermy Treger, Peter Pytel, Aliya N Husain, Jefree J. Schulte

Research output: Contribution to journalReview articlepeer-review

14 Scopus citations


Objectives: To present an index case and review the histologic and electron microscopic findings in chloroquine (CQ) and hydroxychloroquine (HCQ) myopathy, focusing primarily on cardiomyopathy. CQ and HCQ are antimalarial drugs with disease-modifying activity in rheumatic diseases (DMARD) and now are among the most widely used DMARDs. Although they are rare, severe adverse effects caused mainly by deposition of intracellular metabolites in both cardiac and skeletal muscle have been described. Currently, both CQ and HCQ have been proposed to have efficacy for patients with coronavirus disease 2019, and several large centers in the United States and other countries have started clinical trials. Methods: A case of HCQ cardiotoxicity diagnosed on an endomyocardial biopsy is presented. A review of the pathology archives was performed to identify additional cases of CQ or HCQ myopathy, and histologic changes were recorded. A brief literature review with an emphasis on pathologic findings in myopathies was performed. Results: Including the index case, 4 cases of CQ or HCQ myopathy were identified. Light microscopic findings included vacuolated myopathy, and electron microscopic findings included myeloid bodies and curvilinear inclusion bodies. Conclusion: CQ and HCQ myopathy can present following long-Term administration of the drug. The pathologic findings are nonspecific and overlap with other vacuolated myopathies, necessitating careful correlation of the histologic changes with the patient's medical history.

Original languageEnglish (US)
Pages (from-to)793-801
Number of pages9
JournalAmerican journal of clinical pathology
Issue number6
StatePublished - Jun 1 2021
Externally publishedYes


  • COVID-19
  • Cardiomyopathy
  • Chloroquine
  • Hydroxychloroquine
  • Myopathy

ASJC Scopus subject areas

  • Pathology and Forensic Medicine


Dive into the research topics of 'Chloroquine-and Hydroxychloroquine-Induced Cardiomyopathy: A Case Report and Brief Literature Review'. Together they form a unique fingerprint.

Cite this