Platelet aggregates, a marker of severe COVID-19 disease

J Clin Pathol. 2021 Nov;74(11):750-751. doi: 10.1136/jclinpath-2020-206933. Epub 2020 Oct 16.

Abstract

Thrombocytopenia is common in an intensive care unit (ICU) setting due to endogenous and iatrogenic factors. Despite that, thrombocytopenia in patients with severe COVID-19 infections is surprisingly uncommon. By examining the blood film of 20 ICU patients with COVID-19, we observed the presence of platelet aggregates and macrothrombocytes indicating increased platelet activity. We compared these findings with 20 blood films of non-severe COVID-19 cases where these findings were absent. These morphology features could be consistent with severe COVID-19 infection and is further evidence of the important role that platelets play when COVID-19 manifests with thrombotic complications or respiratory failure.

Keywords: blood platelets; morphological and microscopic findings; thrombosis.

MeSH terms

  • Aged
  • Blood Platelets / pathology*
  • Blood Platelets / virology*
  • COVID-19 / blood
  • COVID-19 / complications*
  • Critical Care
  • Humans
  • Middle Aged
  • Platelet Count / methods
  • Thrombocytopenia / blood
  • Thrombocytopenia / physiopathology
  • Thrombocytopenia / virology
  • Thrombosis / blood
  • Thrombosis / physiopathology*
  • Thrombosis / virology*