# Differences in concentration of neuron-specific enolase (NSE), neutrophil elastase (NE), and calcium-binding protein S100B in viral diseases: a pilot study focused on normoglycemic COVID-19 patients

## TL;DR

This pilot study compared levels of specific proteins in normoglycemic COVID-19 patients and healthy individuals to identify potential diagnostic markers.

## Contribution

The study introduces NSE, NE, and S100B as potential biomarkers for diagnosing normoglycemic COVID-19.

## Key findings

- NSE and S100B levels were significantly higher in symptomatic COVID-19 patients.
- Monocyte and neutrophil counts were positively associated with increased odds of being in the study group.
- NSE showed a statistically significant positive association in the multivariate model.

## Abstract

SARS-CoV-2 infection is characterized by a wide spectrum of clinical severity. Despite more than 2 years having passed since the end of the COVID-19 pandemic, the virus’s properties continue to form the basis for developing diagnostic and therapeutic models relevant to future epidemics. The aim of this study was to evaluate the diagnostic utility of classical inflammatory and metabolic markers, as well as potential variables associated with COVID-19 condition, such as neutrophil elastase (NE), neuron-specific enolase (NSE), and S100B protein. The analysis was conducted in carefully selected, homogeneous groups: the study group (patients with symptomatic COVID-19, without comorbidities) and the control group (healthy individuals, without comorbidities), with approximately 100 participants in each group. In the study group, significantly higher values were observed for numerous markers, including basophils, creatinine, eosinophils, HbA1c, HDL cholesterol, lymphocytes, monocytes, neutrophils, hemoglobin, hematocrit, platelets, as well as NSE and S100B. In a multivariate model assessing the likelihood of a result compared to the control group, monocyte count was positively associated with increased odds (OR = 1.6487; 95% CI: 1.2480–2.4318; p = 0.0001). Neutrophil count showed a positive association per 10-unit increase (OR = 1.0377; 95% CI: 1.0214–1.0622; p < 0.0001). Finally, NSE was also positively associated with increased odds (OR = 1.1466 per unit increase; 95% CI: 1.0175–1.2998; p = 0.0218).

Flowchart illustration showing SARS-CoV-2 infection leading to body tissue infection in patients without comorbidities, diagnostic testing for inflammatory and metabolic markers NE, NSE, S100B, and identification of markers remaining significant in a multivariate model.