Prognostic value of neutrophile-to-lymphocyte ratio (NLR) and lactate dehydrogenase (LDH) levels for geriatric patients with COVID-19

The Diagnostic Value of Kinetics of NLR to Identify Secondary Pulmonary Bacterial Infection Among COVID-19 Patients at Single Tertiary Hospital in Indonesia

Purpose

Coronavirus disease 2019 (COVID-19) is a new respiratory tract infection caused by severe acute respiratory syndrome coronavirus-2. The presence of secondary pulmonary bacterial infection (SPBI) made COVID-19 difficult to treat. Neutrophil-lymphocyte count ratio (NLR) is a systemic inflammatory marker used in the diagnosis and prognosis of viral or bacterial infection. At the first 3-5 days after hyperinflammation, it occurs in relation to clinical outcome. Therefore, this study aimed to evaluate the diagnostic value of NLR based on leukocyte kinetics upon admission and after 72 hours among COVID-19 patients with or without SPBI.

Patients and Methods

This retrospective cross-sectional study analyzed medical records data of admitted patients with COVID-19 according to the International Classification of Disease 10th Revision (ICD-10) between January and December 2021. The list of patients was extracted and followed by a hand search to identify the inclusion or exclusion criteria and stratified into proven and non-proven SPBI based on clinical data. The study distinguished between SPBI by means of a cut-off value (COV) on the first (D1) and third day (D3), assessed using receiver operating characteristics (ROC), as well as determined the magnitude of sensitivity, specificity, and prevalence ratio.

Results

A screening process was conducted on 2902 COVID-19 patients, of which 236 were included, accounting for 8.1%. Among these patients, 87 (36.9%) were found to have proven SPBI. A considerable difference in NLR value between proven and non-proven SPBI was observed on both D1 (11.1 vs 4.2) and D3 (15.3 vs 5.2), with optimal COV of NLR on D1, D3 was found to be 5.29, 9.47, respectively (p < 0.001).

Conclusion

NLR on the D1 and D3 distinguished the occurrence of SPBI among COVID-19 patients. The application of NLR assisted in the early determination of bacterial infection and helped in controlling the empirical use of antibiotics.

Serum Lactate Dehydrogenase Level One Week after Admission Is the Strongest Predictor of Prognosis of COVID-19: A Large Observational Study Using the COVID-19 Registry Japan

Clinical features of COVID-19 are diverse, and a useful tool for predicting clinical outcomes based on clinical characteristics of COVID-19 is needed. This study examined the laboratory values and trends that influence mortality in hospitalised COVID-19 patients. Data on hospitalised patients enrolled in a registry study in Japan (COVID-19 Registry Japan) were obtained. Patients with records on basic information, outcomes, and laboratory data on the day of admission (day 1) and day 8 were included. In-hospital mortality was set as the outcome, and associated factors were identified by multivariate analysis using the stepwise method. A total of 8860 hospitalised patients were included. The group with lactate dehydrogenase (LDH) levels >222 IU/L on day 8 had a higher mortality rate compared to the group with LDH levels ≤222 IU/L. Similar results were observed in subgroups formed by age, body mass index (BMI), underlying disease, and mutation type, except for those aged <50 years. When age, sex, BMI, underlying disease, and laboratory values on days 1 and 8 were tested for factors strongly associated with in-hospital mortality, LDH on day 8 was most strongly associated with mortality. LDH level on day 8 was the strongest predictor of in-hospital mortality in hospitalised COVID-19 patients, indicating its potential usefulness in post-treatment decision-making in severe COVID-19 cases.

Correlation of alpha-1 antitrypsin levels and exosome associated neutrophil elastase endothelial injury in subjects with SARS-CoV2 infection

Background

Severe acute respiratory syndrome caused by a novel coronavirus 2 (SARS-CoV-2) has infected more than 18 million people worldwide. The activation of endothelial cells is a hallmark of signs of SARS-CoV-2 infection that includes altered integrity of vessel barrier and endothelial inflammation.

Objectives

Pulmonary endothelial activation is suggested to be related to the profound neutrophil elastase (NE) activity, which is necessary for sterilization of phagocytosed bacterial pathogens. However, unopposed activity of NE increases alveolocapillary permeability and extracellular matrix degradation. The uncontrolled protease activity of NE during the inflammatory phase of lung diseases might be due to the resistance of exosome associated NE to inhibition by alpha-1 antitrypsin.

Method

31 subjects with a diagnosis of SARS-CoV2 infection were recruited in the disease group and samples from 30 voluntaries matched for age and sex were also collected for control.

Results

We measured the plasma levels of exosome-associated NE in SARS-CoV-2 patients which, were positively correlated with sign of endothelial damage in those patients as determined by plasma levels of LDH. Notably, we also found strong correlation with plasma levels of alpha-1 antitrypsin and exosome-associated NE in SARS-CoV-2 patients. Using macrovascular endothelial cells, we also observed that purified NE activity is inhibited by purified alpha-1 antitrypsin while, NE associated with exosomes are resistant to inhibition and show less sensitivity to alpha-1 antitrypsin inhibitory activity, in vitro.

Conclusions

Our results point out the role of exosome-associated NE in exacerbation of endothelial injury in SARS-CoV-2 infection. We have demonstrated that exosome-associated NE could be served as a new potential therapeutic target of severe systemic manifestations of SARS-CoV-2 infection.