Routine blood analysis greatly reduces the false-negative rate of RT-PCR testing for Covid-19

Acta Biomed. 2020 Sep 7;91(3):e2020003. doi: 10.23750/abm.v91i3.9843.

Abstract

Background: The COVID-19 outbreak is now a pandemic disease reaching as much as 210 countries worldwide with more than 2.5 million infected people and nearly 200.000 deaths. Amplification of viral RNA by RT-PCR represents the gold standard for confirmation of infection, yet it showed false-negative rates as large as 15-20% which may jeopardize the effect of the restrictive measures taken by governments. We previously showed that several hematological parameters were significantly different between COVID-19 positive and negative patients. Among them aspartate aminotransferase and lactate dehydrogenase had predictive values as large as 90%. Thus a combination of RT-PCR and blood tests could reduce the false-negative rate of the genetic test.

Methods: We retrospectively analyzed 24 patients showing multiple and inconsistent RT-PCR, test during their first hospitalization period, and compared the genetic tests results with their AST and LDH levels.

Results: We showed that when considering the hematological parameters, the RT-PCR false-negative rates were reduced by almost 4-fold.

Conclusions: The study represents a preliminary work aiming at the development of strategies that, by combining RT-PCR tests with routine blood tests, will lower or even abolish the rate of RT-PCR false-negative results and thus will identify, with high accuracy, patients infected by COVID-19.

Publication types

  • Observational Study

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Aspartate Aminotransferases / blood
  • Betacoronavirus / genetics*
  • Biomarkers / blood
  • COVID-19
  • Coronavirus Infections / blood
  • Coronavirus Infections / diagnosis*
  • Coronavirus Infections / epidemiology
  • Diagnosis, Differential
  • False Negative Reactions
  • Female
  • Follow-Up Studies
  • Hematologic Tests / methods
  • Humans
  • Italy / epidemiology
  • L-Lactate Dehydrogenase / blood
  • Male
  • Middle Aged
  • Pandemics*
  • Pneumonia, Viral / blood
  • Pneumonia, Viral / diagnosis*
  • Pneumonia, Viral / epidemiology
  • RNA, Viral / analysis*
  • Real-Time Polymerase Chain Reaction / methods*
  • Reproducibility of Results
  • Retrospective Studies
  • SARS-CoV-2

Substances

  • Biomarkers
  • RNA, Viral
  • L-Lactate Dehydrogenase
  • Aspartate Aminotransferases