Laboratory test alterations in patients with COVID-19 and non COVID-19 interstitial pneumonia: a preliminary report.

Introduction: Coronavirus disease 19 (COVID-19) is the greatest pandemic in modern history. Laboratory test alterations have been described in COVID-19 patients, but differences with other pneumonias have been poorly investigated to date, especially in Caucasian populations. The aim of this study was to investigate differences and prognostic potential of routine blood tests in a series of Italian patients with COVID-19 and non-COVID-19 interstitial pneumonia.

Methodology: Clinical data and routine laboratory tests of a consecutive series of 30 COVID-19 patients and 30 age and sex matched patients with non COVID-19 interstitial pneumonia have been retrospectively collected. Differences in laboratory tests between patients with COVID-19 and non COVID-19 pneumonias have been investigated, as well as differences between COVID-19 survivors and non survivors.

Results: COVID-19 patients had lower white blood cells, monocytes, neutrophils, and higher platelet counts. In addition, COVID-19 patients showed higher mean platelet volume, lower C reactive protein concentrations, and higher De Ritis ratio. Combined blood cell indexes of systemic inflammation were significantly lower in COVID-19 patients. In further analysis of the COVID-19 group, the neutrophil count, neutrophil to lymphocyte ratio (NLR), derived NLR, systemic inflammation response index and De Ritis ratio, were significantly higher in non survivors than in survivors, while the number of platelets was significantly lower in non survivors.

Conclusions: Our study showed several alterations in blood cell populations and indexes in patients with COVID-19 pneumonia in comparison with patients with non COVID-19 pneumonia. Some of these indexes showed promising prognostic abilities. Further studies are necessary to confirm these results.