Liver Pathology and SARS-CoV-2 Detection in Formalin-Fixed Tissue of Patients With COVID-19

Am J Clin Pathol. 2021 May 18;155(6):802-814. doi: 10.1093/ajcp/aqab009.

Abstract

Objectives: The novel coronavirus, severe acute respiratory syndrome coronavirus 2, causing coronavirus disease 2019 (COVID-19) remains a global health threat and a significant source of human morbidity and mortality. While the virus primarily induces lung injury, it also has been reported to cause hepatic sequelae.

Methods: We aimed to detect the virus in formalin-fixed tissue blocks and document the liver injury patterns in patients with COVID-19 compared with a control group.

Results: We were able to detect viral RNA in the bronchioalveolar cell blocks (12/12, 100%) and formalin-fixed, paraffin-embedded tissue of the lung (8/8, 100%) and liver (4/9, 44%) of patients with COVID-19. Although the peak values of the main liver enzymes and bilirubin were higher in the patients with COVID-19 compared with the control group, the differences were not significant. The main histologic findings were minimal to focal mild portal tract chronic inflammation (7/8, 88%, P < .05) and mild focal lobular activity (6/8, 75%, P = .06).

Conclusions: We found that most patients who died of COVID-19 had evidence of mild focal hepatitis clinically and histologically; however, the virus was detected in less than half of the cases.

Keywords: Autopsy; Cytopathology; Gastrointestinal; Hepatopathology; Molecular diagnostics.

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • COVID-19 / virology*
  • Female
  • Formaldehyde*
  • Humans
  • Inflammation / pathology
  • Liver / pathology*
  • Liver / virology
  • Lung / pathology
  • Lung / virology
  • Male
  • Middle Aged
  • RNA, Viral / genetics
  • SARS-CoV-2 / pathogenicity*
  • Tissue Fixation* / methods

Substances

  • RNA, Viral
  • Formaldehyde