Eosinophils as potential biomarkers in respiratory viral infections

Prognostic value of the platelet, neutrophil, monocyte, basophil, and eosinophil to lymphocyte ratios in patients with severe community-acquired pneumonia (SCAP)

Severe community-acquired pneumonia (SCAP) is a serious respiratory inflammation disease with high morbidity and mortality. This study aimed to evaluate the prognostic value of the platelet-to-lymphocyte ratio (PLR), neutrophil-to-lymphocyte ratio (NLR), monocyte-to-lymphocyte ratio (MLR), basophil-to-lymphocyte ratio (BLR) and eosinophil-to-lymphocyte ratio (ELR) in patients with SCAP. The study retrospectively included 554 patients with SCAP, and the clinical data were obtained from the electronic patient record (EMR) system. The primary outcome was in-hospital mortality, and the secondary outcomes included hospital length of stay (LOS), overall survival (OS), admission to ICU, ICU LOS, and ICU mortality. The results showed that both NLR and BLR were significant but not independent prognostic factors for in-hospital mortality; NLR was negatively correlated with hospital LOS while ELR was positively correlated with hospital LOS; both increased NLR and increased BLR were associated with reduced OS, while increased ELR was associated with improved OS; increased PLR, NLR, MLR, and BLR were all correlated with elevated ICU admission rates, while increased ELR was correlated with a reduced ICU admission rate; ELR was positively correlated with ICU LOS; both higher NLR and higher BLR were associated with increased ICU mortality. In summary, NLR and BLR were useful prognostic factors for clinical outcomes in patients with SCAP.

Eosinophils as modulators of host defense during parasitic, fungal, bacterial, and viral infections

Eosinophils, traditionally associated as central innate effector cells with type 2 immunity during allergic and helminth parasitic diseases, have recently been revealed to have important roles in tissue homeostasis as well as host defense in a broader variety of infectious diseases. In a dedicated session at the 2023 biennial conference of the International Eosinophil Society titled "Eosinophils in Host Defense," the multifaceted roles eosinophils play against diverse pathogens, ranging from parasites to fungi, bacteria, and viruses, were presented. In this review, the session speakers offer a comprehensive summary of recent discoveries across pathogen classes, positioning eosinophils as pivotal leukocytes in both host defense and pathology. By unraveling the intricacies of eosinophil engagement in host resistance, this exploration may provide valuable insights not only to understand specific underpinnings of eosinophil functions related to each class of pathogens but also to develop novel therapeutics effective against a broad spectrum of infectious diseases.

A New Laboratory Tool for COVID-19 Severity Prediction, CENIL Score

BACKGROUND/OBJECTIVES

Several studies investigated the risk factors for severe COVID-19-related outcomes. Early identification and proper treatment of COVID-19 patients who may develop severe pneumonia are crucial. The aim of this study was to detect the importance of the laboratory parameters for risk prediction of severe pneumonia in COVID-19 patients.

METHODS

This retrospective cohort study included COVID-19 patients' laboratory parameters at admission. Biochemical, hematological, coagulation, and inflammatory parameters values were compared between the non-severe and severe groups.

RESULTS

A total of 534 COVID-19 patients were screened, and 472 of them were included in this study. The mean age of patients was 64 (±3.1) years; 242 (51.3%) were men. A total of 204 (43.2%) patients were diagnosed as severe cases. The independent predictors of severe illness were C-reactive peptide, Eosinophil, neutrophil-lymphocyte ratio, interleukin-6, and lactate dehydrogenase. These parameters were named as CENIL scores from 0 to 5 points. The findings of this study indicate that these biomarkers identified tend to increase progressively with disease severity in severe COVID-19 patients. Additionally, the CENIL risk score identified a specific cut-off value of 3, highlighting it as a critical threshold for identifying patients at high risk of severe COVID-19 progression.

CONCLUSIONS

In this study, we identified biomarkers-including CRP, eosinophil count, NLR, IL-6, and LDH-named as CENIL risk score that can help predict the likelihood of severe disease at diagnosis. Clinicians may be more vigilant regarding the development of severe disease in patients with high CENIL risk scores, guided by clinical and radiological findings.

Blood Eosinophils Matter in Post-COVID-19 Pneumonia

BACKGROUND

Even after the development of vaccines, SARS-CoV-2 continues to cause severe pneumonia all over the world. Consequently, in order to improve the management of patients and optimize the use of resources, predictors of disease severity and lung complications after COVID-19 pneumonia are urgently needed. Blood cell count is an easily available and reproducible biomarker. With this study, we aimed to explore the role of eosinophils in predicting disease behavior and pulmonary sequelae at first follow-up with computed tomography (CT).

METHODS

we evaluated blood cell count and other inflammatory markers, both at baseline and during hospitalization, in a large population of hospitalized COVID-19 patients.

RESULTS

327 patients were finally enrolled, 214 were classified as low-intensity medical care (LIMC) and 113 as high-intensity medical care. Eosinophils were higher at discharge in the HIMC group [0.1 (0-0.72) vs. 0.05 (0-0.34) × 109/L; p < 0.0001]. Moreover, in the multivariable analysis, age ≥ 62 years (OR 1.76 (1.05-2.8) p = 0.03) and Δ eosinophils ≥ 0.05 (OR 1.75 (1.05-2.9) p = 0.03) were two independent predictors of residual lung abnormalities in the whole patient population at first follow-up.

CONCLUSIONS

an eosinophil increase during hospitalization could be a potential predictor of pulmonary sequelae in surviving patients after COVID-19 pneumonia.

Cord blood granulocyte levels are associated with severe bronchiolitis in the first year of life

Objectives

Bronchiolitis is a leading cause of infant hospitalisation in the first year of life, and it preferentially affects infants born to mothers with asthma. Here, we evaluate cord blood granulocytes in infants born to mothers with asthma participating in the Breathing for Life Trial (BLT), to investigate early life determinants of bronchiolitis hospitalisation within the first year of life.

Methods

Cord blood from 89 participants was collected into EDTA tubes and processed within 6 h of birth. Cells were stained in whole cord blood for eosinophils (CD45+, CD193+, CD16-), and neutrophils (CD45+, CD193-, CD16+). Medical records were reviewed for bronchiolitis hospitalisation in the first 12 months of life. Statistical analyses were conducted using Stata IC16.1.

Results

Logistic regression adjusted for caesarean section, gestational age, maternal smoking during pregnancy, foetal heart deceleration during labour, and season of birth revealed an association between cord blood eosinophil levels and bronchiolitis hospitalisation in the first 12 months of life with an Area Under the Curve (AUC) of the Receiver Operating Characteristic (ROC) curve of 0.943 (aOR = 1.35, P = 0.011). Neutrophils were associated with the risk of bronchiolitis hospitalisation in a univariable logistic regression (OR = 0.93, P = 0.029); however, there was no statistical significance in the adjusted model.

Conclusions

Higher eosinophil numbers in cord blood were associated with bronchiolitis hospitalisation in the first 12 months in a cohort of infants born to asthmatic mothers. This suggests that susceptibility to bronchiolitis in later life is influenced by the immune cell profile prior to viral infection.

Aberrant innate immune profile associated with COVID-19 mortality in Pretoria, South Africa

The African continent reported the least number of COVID-19 cases and deaths of all the continents, although the exact reasons for this are still unclear. In addition, little is known about the immunological profiles associated with COVID-19 mortality in Africa. The present study compared clinical and immunological parameters, as well as treatment outcomes in patients admitted with COVID-19 in Pretoria, South Africa, to determine if these parameters correlated with mortality in this population. The in-hospital mortality rate for the cohort was 15.79%. The mortality rate in people living with HIV (PLWH) was 10.81% and 17.16% in people without HIV (p = 0.395). No differences in age (p = 0.099), gender (p = 0.127) or comorbidities were found between deceased patients and those who survived. All four of the PLWH who died had a CD4+ T-cell count <200 cells/mm3, a significantly higher HIV viral load than those who survived (p = 0.009), and none were receiving antiretroviral therapy. Seven of 174 (4%) patients had evidence of auto-antibodies neutralizing Type 1 interferons (IFNs). Two of the them died, and their presence was significantly associated with mortality (p = 0.042). In the adjusted model, the only clinical parameters associated with mortality were: higher fraction of inspired oxygen (FiO2) (OR: 3.308, p = 0.011) indicating a greater need for oxygen, high creatinine (OR: 4.424, p = 0.001) and lower platelet counts (OR: 0.203, p = 0.009), possibly secondary to immunothrombosis. Overall, expression of the co-receptor CD86 (p = 0.021) on monocytes and percentages of CD8+ effector memory 2 T-cells (OR: 0.45, p = 0.027) was lower in deceased patients. Decreased CD86 expression impairs the development and survival of effector memory T-cells. Deceased patients had higher concentrations of RANTES (p = 0.003), eotaxin (p = 0.003) and interleukin (IL)-8 (p < 0.001), all involved in the activation and recruitment of innate immune cells. They also had lower concentrations of transforming growth factor (TGF)-β1 (p = 0.40), indicating an impaired anti-inflammatory response. The immunological profile associated with COVID-19 mortality in South Africa points to the role of aberrate innate immune responses.

[Assessment of blood eosinophil count in respiratory disease from primary care]

Most physicians in general, and family physicians in particular, are familiar with certain parameters when ordering a hematological study, such as hemoglobin (including hematocrit and its features), leukocytes (including lymphocytes) and platelets. Nevertheless, there are two values that we use to overlook which are eosinophils and basophils. Specifically, eosinophils have a tendency to increase with allergic pathology. This article focuses on this type of cells, helping to interpret the values obtained and highlighting their importance in two of the most frequent respiratory pathologies in primary care: asthma and COPD. In addition to observing how the increase or normality of these parameters condition the diagnosis, phenotype and even the treatment.

Eosinophil activation during immune responses: an ultrastructural view with an emphasis on viral diseases

Eosinophils are cells of the innate immune system that orchestrate complex inflammatory responses. The study of the cell biology of eosinophils, particularly associated with cell activation, is of great interest to understand their immune responses. From a morphological perspective, activated eosinophils show ultrastructural signatures that have provided critical insights into the comprehension of their functional capabilities. Application of conventional transmission electron microscopy in combination with quantitative assessments (quantitative transmission electron microscopy), molecular imaging (immunoEM), and 3-dimensional electron tomography have generated important insights into mechanisms of eosinophil activation. This review explores a multitude of ultrastructural events taking place in eosinophils activated in vitro and in vivo as key players in allergic and inflammatory diseases, with an emphasis on viral infections. Recent progress in our understanding of biological processes underlying eosinophil activation, including in vivo mitochondrial remodeling, is discussed, and it can bring new thinking to the field.

Ally, adversary, or arbitrator? The context-dependent role of eosinophils in vaccination for respiratory viruses and subsequent breakthrough infections

Eosinophils are a critical type of immune cell and central players in type 2 immunity. Existing literature suggests that eosinophils also can play a role in host antiviral responses, typically type 1 immune events, against multiple respiratory viruses, both directly through release of antiviral mediators and indirectly through activation of other effector cell types. One way to prime host immune responses toward effective antiviral responses is through vaccination, where typically a type 1-skewed immunity is desirable in the context of intracellular pathogens like respiratory viruses. In the realm of breakthrough respiratory viral infection in vaccinated hosts, an event in which virus can still establish productive infection despite preexisting immunity, eosinophils are most prominently known for their link to vaccine-associated enhanced respiratory disease upon natural respiratory syncytial virus infection. This was observed in a pediatric cohort during the 1960s following vaccination with formalin-inactivated respiratory syncytial virus. More recent research has unveiled additional roles of the eosinophil in respiratory viral infection and breakthrough infection. The specific contribution of eosinophils to the quality of vaccine responses, vaccine efficacy, and antiviral responses to infection in vaccinated hosts remains largely unexplored, especially regarding their potential roles in protection. On the basis of current findings, we will speculate upon the suggested function of eosinophils and consider the many potential ways by which eosinophils may exert protective and pathological effects in breakthrough infections. We will also discuss how to balance vaccine efficacy with eosinophil-related risks, as well as the use of eosinophils and their products as potential biomarkers of vaccine efficacy or adverse events.

Application of peripheral blood routine parameters in the diagnosis of influenza and Mycoplasma pneumoniae

OBJECTIVES

Influenza and Mycoplasma pneumoniae infections often present concurrent and overlapping symptoms in clinical manifestations, making it crucial to accurately differentiate between the two in clinical practice. Therefore, this study aims to explore the potential of using peripheral blood routine parameters to effectively distinguish between influenza and Mycoplasma pneumoniae infections.

METHODS

This study selected 209 influenza patients (IV group) and 214 Mycoplasma pneumoniae patients (MP group) from September 2023 to January 2024 at Nansha Division, the First Affiliated Hospital of Sun Yat-sen University. We conducted a routine blood-related index test on all research subjects to develop a diagnostic model. For normally distributed parameters, we used the T-test, and for non-normally distributed parameters, we used the Wilcoxon test.

RESULTS

Based on an area under the curve (AUC) threshold of ≥ 0.7, we selected indices such as Lym# (lymphocyte count), Eos# (eosinophil percentage), Mon% (monocyte percentage), PLT (platelet count), HFC# (high fluorescent cell count), and PLR (platelet to lymphocyte ratio) to construct the model. Based on these indicators, we constructed a diagnostic algorithm named IV@MP using the random forest method.

CONCLUSIONS

The diagnostic algorithm demonstrated excellent diagnostic performance and was validated in a new population, with an AUC of 0.845. In addition, we developed a web tool to facilitate the diagnosis of influenza and Mycoplasma pneumoniae infections. The results of this study provide an effective tool for clinical practice, enabling physicians to accurately diagnose and differentiate between influenza and Mycoplasma pneumoniae infection, thereby offering patients more precise treatment plans.

Clinical and hematological characteristics of children infected with the omicron variant of SARS-CoV-2: role of the combination of the neutrophil: lymphocyte ratio and eosinophil count in distinguishing severe COVID-19

Purpose

Investigate the clinical/hematological characteristics of children infected with the Omicron variant of severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) and identify an effective indicator to distinguish coronavirus disease 2019 (COVID-19) severity in children.

Methods

A retrospective study was conducted through electronic medical records from pediatric patients. The demographic, clinical, and routine blood test (RBT) features of children diagnosed by real-time PCR for SARS-CoV-2 were collected.

Results

Data of 261 patients were analyzed. The most common abnormality shown by RBTs was increased monocyte count (68%). Children had "mild-moderate" or "severe" forms of COVID-19. Prevalence of abnormal neutrophil count (p = 0.048), eosinophil count (p = 0.006), mean corpuscular volume (p = 0.033), mean platelet volume (p = 0.006), platelet-large cell ratio (p = 0.043), and red blood cell distribution width-standard deviation (p = 0.031) were significantly different in the two types. A combination of the neutrophil: lymphocyte ratio (NLR) and eosinophil count for diagnosing severe COVID-19 presented the largest AUC (0.688, 95% CI = 0.599-0.777; p < 0.001), and the AUC increased with a decrease in age.

Conclusions

Combination of the NLR and eosinophil count might be a promising indicator for identifying severe COVID-19 in children at infection onset.

Spontaneous Lethal Outbreak of Influenza A Virus Infection in Vaccinated Sows on Two Farms Suggesting the Occurrence of Vaccine-Associated Enhanced Respiratory Disease with Eosinophilic Lung Pathology

Influenza A virus (IAV) infections in swine are usually subclinical, but they can reach high morbidity rates. The mortality rate is normally low. In this study, six vaccinated, spontaneously deceased sows revealed IAV infection and enhanced neutrophilic bronchopneumonia with unexpectedly large numbers of infiltrating eosinophils. The purpose of this study was to characterize these lung lesions with special emphasis on the phenotypes of inflammatory cells, the presence of eosinophilic peroxidase (EPO), and neutrophil extracellular traps (NETs). The number of Sirius red-stained eosinophils was significantly higher in the lungs of IAV-infected sows compared to healthy pigs, indicating a migration of eosinophils from blood vessels into the lung tissue stimulated by IAV infection. The detection of intra- and extracellular EPO in the lungs suggests its contribution to pulmonary damage. The presence of CD3+ T lymphocytes, CD20+ B lymphocytes, and Iba-1+ macrophages indicates the involvement of cell-mediated immune responses in disease progression. Furthermore, high numbers of myeloperoxidase-positive cells were detected. However, DNA-histone-1 complexes were reduced in IAV-infected sows, leading to the hypothesis that NETs are not formed in the IAV-infected sows. In conclusion, our findings in the lungs of IAV-infected vaccinated sows suggest the presence of so far unreported field cases of vaccine-associated enhanced respiratory disease.

Immune Response to Respiratory Viral Infections

The respiratory system is constantly exposed to viral infections that are responsible for mild to severe diseases. In this narrative review, we focalized the attention on respiratory syncytial virus (RSV), influenza virus, and severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) infections, responsible for high morbidity and mortality in the last decades. We reviewed the human innate and adaptive immune responses in the airways following infection, focusing on a particular population: newborns and pregnant women. The recent Coronavirus disease-2019 (COVID-19) pandemic has highlighted how our interest in viral pathologies must not decrease. Furthermore, we must increase our knowledge of infection mechanisms to improve our future defense strategies.

Dimethyl fumarate alleviates allergic asthma by strengthening the Nrf2 signaling pathway in regulatory T cells

Allergic asthma is a widely prevalent inflammatory condition affecting people across the globe. T cells and their secretory cytokines are central to the pathogenesis of allergic asthma. Here, we have evaluated the anti-inflammatory impact of dimethyl fumarate (DMF) in allergic asthma with more focus on determining its effect on T cell responses in allergic asthma. By utilizing the ovalbumin (OVA)-induced allergic asthma model, we observed that DMF administration reduced the allergic asthma symptoms and IgE levels in the OVA-induced mice model. Histopathological analysis showed that DMF treatment in an OVA-induced animal model eased the inflammation in the nasal and bronchial tissues, with a particular decrease in the infiltration of immune cells. Additionally, RT-qPCR analysis exhibited that treatment of DMF in an OVA-induced model reduced the expression of inflammatory cytokine (IL4, IL13, and IL17) while augmenting anti-inflammatory IL10 and Foxp3 (forkhead box protein 3). Mechanistically, we found that DMF increased the expression of Foxp3 by exacerbating the expression of nuclear factor E2-related factor 2 (Nrf2), and the in-vitro activation of Foxp3+ Tregs leads to an escalated expression of Nrf2. Notably, CD4-specific Nrf2 deletion intensified the allergic asthma symptoms and reduced the in-vitro iTreg differentiation. Meanwhile, DMF failed to exert protective effects on OVA-induced allergic asthma in CD4-specific Nrf2 knock-out mice. Overall, our study illustrates that DMF enhances Nrf2 signaling in T cells to assist the differentiation of Tregs, which could improve the anti-inflammatory immune response in allergic asthma.

Eosinophils in Oral Disease: A Narrative Review

The prevalence of diseases characterised by eosinophilia is on the rise, emphasising the importance of understanding the role of eosinophils in these conditions. Eosinophils are a subset of granulocytes that contribute to the body's defence against bacterial, viral, and parasitic infections, but they are also implicated in haemostatic processes, including immunoregulation and allergic reactions. They contain cytoplasmic granules which can be selectively mobilised and secrete specific proteins, including chemokines, cytokines, enzymes, extracellular matrix, and growth factors. There are multiple biological and emerging functions of these specialised immune cells, including cancer surveillance, tissue remodelling and development. Several oral diseases, including oral cancer, are associated with either tissue or blood eosinophilia; however, their exact mechanism of action in the pathogenesis of these diseases remains unclear. This review presents a comprehensive synopsis of the most recent literature for both clinicians and scientists in relation to eosinophils and oral diseases and reveals a significant knowledge gap in this area of research.

Asthma in patients with the syndrome of undifferentiated dysplasia of connective tissue: peculiarities of the course or mutually aggravating mechanisms?

OBJECTIVE

Aim: To analyse laboratory and biochemical features of the severe persistent course of asthma in patients with undifferentiated connective tissue dysplasia (UCTD) syndrome, and their phenotypic and visceral stigmas of dysembryogenesis.

PATIENTS AND METHODS

Materials and Methods: We enrolled 60 male patients with asthma, aged from 23 to 62 years (mean age (46.83 ±0.85) years): 30 patients with the background of UCTD, and 30 - without UCTD. We analysed clinical, somatometric, surveying (original questionnaire based on the phenotypic map of Glesby), instrumental (spirography, echocardiography, endoscopy, esophagofibrogastroduodenoscopy) and laboratory (including eosinophilic granulocytes and aldosterone levels) data.

RESULTS

Results: Correlations were found in men with UCTD between the number of UCTD markers and rate of earlobe diagonal fold (r=+0.75; р<0.05), asthenic constitution (r=+0.72; р<0.05), easy bruising (r=+0.7; p<0.05) and straight abdominal line hernia (r=+0.52; p<0.05). Average aldosterone serum level in patients with UCTD (176,10 ±11,22) was significantly higher than in those without UCTD (142,77 ±9,43), (p<0.05), as well as average eosinophils levels (1.3 ±0.25 vs. 0.57 ±0.12, p<0.05). In the absolute majority of patients with UCTD (93.3%) asthma onset was confirmed after pneumonia, and their age of asthma manifestation was significantly higher (37.2 ±1.21) than in patients without UCTD (21.4 ±1.13). Also, in patients with UCTD there was a high number of severe exacerbations during the last year (2.7 ±0.12 per year) on the background of high doses of combined inhaled glucocorticosteroids use.

CONCLUSION

Conclusions: Identified "phenotypic profile", clinical and biochemical features of patients with asthma on the background of UCTD syndrome, which determine the severe course and early formation of asthma complications, will further accelerate the diagnosis of this asthma phenotype and improve approaches to the selection of treatment regimens for these patients.

Persistence of circulating CD169+monocytes and HLA-DR downregulation underline the immune response impairment in PASC individuals: the potential contribution of different COVID-19 pandemic waves

The use of CD169 as a marker of viral infection has been widely discussed in the context of COVID-19, and in particular, its crucial role in the early detection of SARS-CoV-2 infection and its association with the severity and clinical outcome of COVID-19 were demonstrated. COVID-19 patients show relevant systemic alteration and immunological dysfunction that persists in individuals with post-acute sequelae of SARS-CoV-2 infection (PASC). It is critical to implement the characterization of the disease, focusing also on the possible impact of the different COVID-19 waves and the consequent effects found after infection. On this basis, we evaluated by flow cytometry the expression of CD169 and HLA-DR on monocytes from COVID-19 patients and PASC individuals to better elucidate their involvement in immunological dysfunction, also evaluating the possible impact of different pandemic waves. The results confirm CD169 RMFI is a good marker of viral infection. Moreover, COVID-19 patients and PASC individuals showed high percentage of CD169+ monocytes, but low percentage of HLA-DR+ monocytes and the alteration of systemic inflammatory indices. We have also observed alterations of CD169 and HLA-DR expression and indices of inflammation upon different COVID-19 waves. The persistence of specific myeloid subpopulations suggests a role of CD169+ monocytes and HLA-DR in COVID-19 disease and chronic post-infection inflammation, opening new opportunities to evaluate the impact of specific pandemic waves on the immune response impairment and systemic alterations with the perspective to provide new tools to monitoring new variants and diseases associated to emerging respiratory viruses.

ANCOC Score to Predict Mortality in Different SARS-CoV-2 Variants and Vaccination Status

BACKGROUND

More than three years after the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic outbreak, hospitals worldwide are still affected by coronavirus disease 19 (COVID-19). The availability of a clinical score that can predict the risk of death from the disease at the time of diagnosis and that can be used even if population characteristics change and the virus mutates can be a useful tool for emergency physicians to make clinical decisions. During the first COVID-19 waves, we developed the ANCOC (age, blood urea nitrogen, C-reactive protein, oxygen saturation, comorbidities) score, a clinical score based on five main parameters (age, blood urea nitrogen, C-reactive protein, oxygen saturation, comorbidities) that accurately predicts the risk of death in patients infected with SARS-CoV-2. A score of less than -1 was associated with 0% mortality risk, whereas a score of 6 was associated with 100% risk of death, with an overall accuracy of 0.920. The aim of our study is to internally validate the ANCOC score and evaluate whether it can predict 60-day mortality risk independent of vaccination status and viral variant.

METHODS

We retrospectively enrolled 843 patients admitted to the emergency department (ED) of our hospital with a diagnosis of COVID-19. A total of 515 patients were admitted from July 2021 to September 2021, when the Delta variant was prevalent, and 328 in January 2022, when the Omicron 1 variant was predominant. All patients included in the study had a diagnosis of COVID-19 confirmed by polymerase chain reaction (PCR) on an oropharyngeal swab. Demographic data, comorbidities, vaccination data, and various laboratory, radiographic, and blood gas parameters were collected from all patients to determine differences between the two waves. ANCOC scores were then calculated for each patient, ranging from -6 to 6.

RESULTS

Patients infected with the Omicron variant were significantly older and had a greater number of comorbidities, of which hypertension and chronic obstructive pulmonary disease (COPD) were the most common. Immunization was less common in Delta patients than in Omicron patients (34% and 56%, respectively). To assess the accuracy of mortality prediction, we constructed a receiver operating characteristic (ROC) curve and found that the area under the ROC curve was greater than 0.8 for both variants. These results suggest that the ANCOC score is able to predict 60-day mortality regardless of viral variant and whether the patient is vaccinated or not.

CONCLUSION

In a population with increasingly high vaccination rates, several parameters may be considered prognostic for the risk of fatal outcomes. This study suggests that the ANCOC score can be very useful for the clinician in an emergency setting to quickly understand the patient's evolution and provide proper attention and the most appropriate treatments.