The diagnostic and prognostic role of neutrophil-to-lymphocyte ratio in COVID-19: a systematic review and meta-analysis

Inflammatory Biomarkers for Assessing In-Hospital Mortality Risk in Severe COVID-19-A Retrospective Study

(1) Background: Our study aims to investigate the utility of inflammatory factors as prognostic indicators for disease severity and mortality in COVID-19 patients admitted to the Intensive Care Unit (ICU) Department of Pelican Clinical Hospital Oradea Romania. While elevated white blood cell (WBC) levels are associated with COVID-19 severity and mortality, they may not effectively predict the risk of death; (2) Methods: In our ICU department, we conducted assessments on the 10th and 14th days of COVID-19 patients' hospitalization, measuring the following markers: C-reactive protein (CRP) levels, procalcitonin (PCT) levels, granulocytes/lymphocytes (G/L) ratios, ferritin levels, age, and obesity status. We included a total of 209 eligible COVID-19 patients in the final analysis. Our goal was to identify biomarkers that could quickly identify high-risk patients with a potential for disease progression and mortality; (3) Results: Our study (a retrospective, single-center observational cohort study) demonstrated statistically significant differences in predicting mortality and disease severity based on G/L ratio (p < 0.0001), PCT (p < 0.0002), CRP (p < 0.0001), ferritin (p < 0.0001), age (p < 0.0001), and obesity (p < 0.0001); (4) Conclusions: Having a G/L ratio exceeding 20 units, along with elevated levels of PCR, PCT, and ferritin in older and obese patients on the 3rd day of ICU admission, represents significant risk factors for in-hospital mortality in severe COVID-19 patients.

Sociodemographic, clinical and laboratory characteristics and risk factors for mortality of hospitalized COVID-19 patients at alternate care site: a Latin American experience

BACKGROUND

The establishment of Alternate Care Sites (ACS) helped the most severely impacted countries expand their response capability. The aim of this study was to evaluate the clinical characteristics and risk factors associated with the mortality of hospitalized COVID-19 patients at Alternate Care Site in Mexico City.

PATIENTS AND METHODS

A monocentric cohort study was conducted at Mexico City's Temporary Unit COVID-19 (UTC-19). Sociodemographic, clinical, laboratory and treatment variables were included in the analysis.

RESULTS

A total of 4865 patients were included, with a mean age of 49.33 years ± SD 15.28 years (IQR 38 to 60 years); 50.53% were women. 63.53% of the patients presented at least one comorbidity, the most frequent being: obesity (39.94%), systemic arterial hypertension (25.14%), and diabetes mellitus (21.52%). A total of 4549 patients (93.50%) were discharged due to improvement, 64 patients (1.31%) requested voluntary discharge, 39 patients (0.80%) were referred to another unit, and 213 patients (4.37%) died. Factors that were independently and significantly associated with death included male gender (odds ratio [OR], 1.60), age ≥ 50 years (OR 14.75), null or low schooling (OR 3.47), have at least one comorbidity (OR 3.26), atrial fibrillation (OR 22.14). In the multivariate analysis, the lymphopenia ≤ 1 × 103/μL (OR 1.91), and having required steroid treatment (OR 2.85), supplemental oxygen with high-flow nasal cannula (OR 3.12) or invasive mechanical ventilation (OR 42.52), was significantly associated with an increased risk of death.

CONCLUSIONS

This study identified the clinical characteristics and risk factors for mortality of hospitalized COVID-19 patients at ACS in Mexico City.KEY MESSAGESAn Alternate Care Site (ACS) is any building or structure that is temporarily converted or constructed for healthcare use during a public health emergency.Factors associated with death included male gender, age over 50 years, and lower educational attainment (elementary school or less).The findings corroborate the utility of the CALL score as a predictor of mortality; lymphopenia ≤1 × 103/μL was the most relevant biomarker.

Clinical variables associated with late-onset thrombotic and cardiovascular events, after SARS-CoV-2 infection, in a cohort of patients from the first epidemic wave: an 18-month analysis on the "Surviving-COVID" cohort from Bergamo, Italy

Importance

Population studies have recorded an increased, unexplained risk of post-acute cardiovascular and thrombotic events, up to 1 year after acute severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection.

Objectives

To search for clinical variables and biomarkers associated with late post-acute thrombotic and cardiovascular events after SARS-CoV-2 infection.

Design

Retrospective cohort study.

Setting

Third-level referral hospital in Bergamo (Italy).

Participants

Analysis of an existing database of adult patients, who received care for SARS-CoV-2 infection at our institution between 20 February and 30 September 2020, followed up on a single date ("entry date") at 3-6 months.

Exposure

Initial infection by SARS-CoV-2.

Main outcomes and measures

Primary outcome: occurrence, in the 18 months after entry date, of a composite endpoint, defined by the International Classification of Diseases-9th edition (ICD-9) codes for at least one of: cerebral/cardiac ischemia, venous/arterial thrombosis (any site), pulmonary embolism, cardiac arrhythmia, heart failure. Measures (as recorded on entry date): history of initial infection, symptoms, current medications, pulmonary function test, blood tests results, and semi-quantitative radiographic lung damage (BRIXIA score). Individual clinical data were matched to hospitalizations, voluntary vaccination against SARS-CoV-2 (according to regulations and product availability), and documented reinfections in the following 18 months, as recorded in the provincial Health Authority database. A multivariable Cox proportional hazard model (including vaccine doses as a time-dependent variable) was fitted, adjusting for potential confounders. We report associations as hazard ratios (HR) and 95% confidence intervals (CI).

Results

Among 1,515 patients (948 men, 62.6%, median age 59; interquartile range: 50-69), we identified 84 endpoint events, occurring to 75 patients (5%): 30 arterial thromboses, 11 venous thromboses, 28 arrhythmic and 24 heart failure events. From a multivariable Cox model, we found the following significant associations with the outcome: previous occurrence of any outcome event, in the 18 months before infection (HR: 2.38; 95% CI: 1.23-4.62); BRIXIA score ≥ 3 (HR: 2.43; 95% CI: 1.30-4.55); neutrophils-to-lymphocytes ratio ≥ 3.3 (HR: 2.60; 95% CI: 1.43-4.72), and estimated glomerular filtration rate < 45 ml/min/1.73 m2 (HR: 3.84; 95% CI: 1.49-9.91).

Conclusions and relevance

We identified four clinical variables, associated with the occurrence of post-acute thrombotic and cardiovascular events, after SARS-CoV-2 infection. Further research is needed, to confirm these results.

Association between the Neutrophil-to-Lymphocyte Ratio and Inpatient Mortality in Hospitalized Older Veterans with COVID-19 Infection

OBJECTIVES

Determine the association of high neutrophil-to-lymphocyte ratio (NLR) values with inpatient mortality and other outcomes in older veterans hospitalized with coronavirus disease 2019 (COVID-19).

METHODS

This was a retrospective, multicenter, cohort study of hospitalized adults, with laboratory-confirmed COVID-19 infection who were studied for 1 year after discharge or until death. The NLR was categorized into tertiles, and we determined frailty status with the 31-item Veterans Affairs Frailty Index. Multivariate logistic regression and adjusted odds ratios (aORs) with 95% confidence intervals (CIs) were performed to assess the association between NLR and clinical outcomes.

RESULTS

The study included 615 hospitalized adult veterans, mean age 66.12 (standard deviation 14.79) years, 93.82% (n = 577) male, 57.56% (n = 354) White, 81.0% (n = 498) non-Hispanic, median body mass index of 30.70 (interquartile range 25.64-34.99, standard deviation 7.13), and median length of stay of 8 days (interquartile range 3-15). Individuals in the middle and upper tertile groups had higher inpatient mortality (8.37%, n = 17 and 18.36%, n = 38, respectively) as compared with the lower tertile (2.93%, n = 6, P < 0.001). Compared with the lowest tertile, the middle and upper tertiles had a higher risk of inpatient mortality (aOR 3.75, 95% CI 1.38-10.21, P = 0.01, and aOR 8.13, 95% CI 3.18-20.84, P < 0.001, respectively). The highest tertile had a higher odds of intensive care unit admission (aOR 4.47, 95% CI 2.33-8.58, P < 0.001) and intensive care unit transfer (aOR 3.54, 95% CI 1.84-6.81, P < 0.001).

CONCLUSIONS

The NLR score is a clinically useful tool to predict in-hospital mortality in older patients with COVID-19.

[LDH-neutrophil-lymphocyte index as a predictor of 28-day mortality in patients with COVID-19]

Background

Coronavirus disease 2019 (COVID-19) represents the greatest health crisis of our times; it was declared by WHO a pandemic in March 2020. The risk of presenting a severe disease is inter-individual, since it varies according to age, comorbidities, and immunological status, in addition to the type of SARS-CoV-2 variant. The neutrophil/lymphocyte ratio (NLR) and lactic dehydrogenase (LDH) are widely used markers to assess the severity and predict the course of the disease in patients with COVID-19, with a direct relationship of higher value-worse prognosis.

Objective

To verify if the LDH-neutrophil-lymphocyte index calculated from laboratory tests taken within the first 24 hours of admission is useful as a predictor of 28-day mortality in adult patients diagnosed with COVID-19.

Material and methods

Retrospective and analytical cohort study. All consecutive patients over 16 years of any gender, admitted to a tertiary care center from March 2020 to March 2021, who had a diagnosis of COVID-19 with a positive PCR for SARS-CoV-2, were included.

Results

Higher levels of the LDHNL index were associated with higher mortality in patients hospitalized for COVID-19 (Q2 vs. Q1: RR 1.52 [1.24-1.87], p < 0.05; Q3 vs. Q1: RR 1.87 [1.55-2.25], p < 0.05; and Q4 vs. Q1: RR 2.74 [2.22-3-39], p < 0.05).

Conclusions

The serum LDHNL index taken in the first 24 hours of admission can help to predict early the risk of mortality in hospitalized patients with COVID-19.

Neutrophil to lymphocyte ratio and platelet to lymphocyte ratio, are they markers of COVID-19 severity or old age and frailty? A comparison of two distinct cohorts

The neutrophil-lymphocyte ratio (NLR) and platelet-lymphocyte ratio (PLR) are simple markers of systemic inflammatory responses. It has been previously suggested that they can predict COVID-19 severity. Age and frailty may also influence their values. This study aimed to evaluate the impact of COVID-19 severity versus age and frailty on NLR and PLR values. This was a retrospective, observational two cohorts' comparative study. The first cohort is comprised of patents positive for SARS-CoV-2, with mild or asymptomatic disease, admitted to designated COVID-19 departments in a large geriatric medical center (GMC). The second included patients with COVID-19 admitted to designated COVID-19 departments in a large general hospital for symptomatic disease from March 2020 to March 2021. We compared baseline characteristics including comorbidities and chronic medications, disease symptoms, laboratory tests and compared the NLR and PLR between the two groups. The 177 patients admitted to the COVID-designated department in the GMC were over three decades older than the 289 COVID-19 patients admitted to the general hospital care (HC). They had substantially more comorbidities and chronic medications. All common disease symptoms were significantly more common in the HC group. Almost two thirds of the GMC patients remained asymptomatic compared to 2.1% in the HC group. Inflammatory markers, such as CRP and LDH, were significantly higher in the HC group. The NLR and PLR were both significantly higher in the GMC cohort comprised of older frailer patients with milder disease. NLR and PLR seem to be affected more by age and frailty than COVID-19 severity.

Impact of the SARS-CoV-2 nucleocapsid 203K/204R mutations on the inflammatory immune response in COVID-19 severity

BACKGROUND

The excessive inflammatory responses provoked by SARS-CoV-2 infection are critical factors affecting the severity and mortality of COVID-19. Previous work found that two adjacent co-occurring mutations R203K and G204R (KR) on the nucleocapsid (N) protein correlate with increased disease severity in COVID-19 patients. However, links with the host immune response remain unclear.

METHODS

Here, we grouped nasopharyngeal swab samples of COVID-19 patients into two cohorts based on the presence and absence of SARS-CoV-2 nucleocapsid KR mutations. We performed nasopharyngeal transcriptome analysis of age, gender, and ethnicity-matched COVID-19 patients infected with either SARS-CoV-2 with KR mutations in the N protein (KR patients n = 39) or with the wild-type N protein (RG patients n = 39) and compared to healthy controls (n = 34). The impact of KR mutation on immune response was further characterized experimentally by transcriptomic and proteomic profiling of virus-like-particle (VLP) incubated cells.

RESULTS

We observed markedly elevated expression of proinflammatory cytokines, chemokines, and interferon-stimulated (ISGs) genes in the KR patients compared to RG patients. Using nasopharyngeal transcriptome data, we found significantly higher levels of neutrophils and neutrophil-to-lymphocyte (NLR) ratio in KR patients than in the RG patients. Furthermore, transcriptomic and proteomic profiling of VLP incubated cells confirmed a similar hyper-inflammatory response mediated by the KR variant.

CONCLUSIONS

Our data demonstrate an unforeseen connection between nucleocapsid KR mutations and augmented inflammatory immune response in severe COVID-19 patients. These findings provide insights into how mutations in SARS-CoV-2 modulate host immune output and pathogenesis and may contribute to more efficient therapeutics and vaccine development.

Therapeutic Candidates for Alzheimer's Disease: Saponins

Drug development for Alzheimer's disease, the leading cause of dementia, has been a long-standing challenge. Saponins, which are steroid or triterpenoid glycosides with various pharmacological activities, have displayed therapeutic potential in treating Alzheimer's disease. In a comprehensive review of the literature from May 2007 to May 2023, we identified 63 references involving 40 different types of saponins that have been studied for their effects on Alzheimer's disease. These studies suggest that saponins have the potential to ameliorate Alzheimer's disease by reducing amyloid beta peptide deposition, inhibiting tau phosphorylation, modulating oxidative stress, reducing inflammation, and antiapoptosis. Most intriguingly, ginsenoside Rg1 and pseudoginsenoside-F11 possess these important pharmacological properties and show the best promise for the treatment of Alzheimer's disease. This review provides a summary and classification of common saponins that have been studied for their therapeutic potential in Alzheimer's disease, showcasing their underlying mechanisms. This highlights the promising potential of saponins for the treatment of Alzheimer's disease.

Treatment Outcome with High versus low-to-moderate Dosing of Corticosteroids in Early vis-a-vis Late-onset Hypoxic Cases of COVID-19: A Multicentric Retrospective Cohort Study

Background

Corticosteroid dosing in COVID-19 cases associated with early-onset and late-onset hypoxia have not been separately explored.

Methods

In this retrospective cohort study, we divided hypoxic COVID-19 cases into groups based on timing of initiation of corticosteroids relative to onset of symptoms; Group A (≤6th day), Group B (7th-9th day) and Group C (≥10th day), each group being sub-grouped into high and low-to-moderate dose corticosteroid recipients. Cox regression with propensity scoring was used to compare 28-day mortality between high and low-to-moderate dose recipients separately in Group A, Group B, Group C.

Results

Among 505 patients included, propensity score matched Cox regression showed greater risk of all-cause mortality among high dose recipients in Group A [HR= 7.35, 95%CI 3.36-16.11, p-value<0·01, N=114] and Group B [HR=3.17, 95%CI 1.65-6.07, p-value<0·01, N=251]. In Group C, mortality was lowest [12.8% (18/140)] with no significant difference between sub-groups [HR=2.52, 95%CI 0.22-29.15, p-value=0.459, N=140]. Kruskal-Wallis Test between Group A, Group B and Group C for six pre-defined exposure variables showed significant differences for Neutrophil:Lymphocyte Ratio (NLR).

Conclusion

When steroids were initiated early (owing to an earlier onset of hypoxic symptoms), a high dose of corticosteroid was associated with greater overall 28-day mortality compared to a low-to-moderate dose. NLR, a marker for individual immune response, varied between treatment groups.

Outcomes in COVID-19 Patients with Pneumonia Treated with High-Flow Oxygen Therapy and Baricitinib—Retrospective Single-Center Study

Background. The aim of the study was to assess the effect of baricitinib on 28-day all-cause mortality and the progression of respiratory failure in patients needing transfer to the intensive care unit (ICU) with COVID-19 pneumonia treated with high-flow oxygen therapy. Methods. This retrospective study included hospitalized patients with COVID-19 pneumonia treated with high-flow oxygen non-invasive ventilation receiving standard of care (SOC) or SOC in addition to baricitinib. Data on patients’ characteristics, pro-inflammatory markers, D dimer, and National Early Warning Score 2 (NEWS2) values were collected and compared between groups. The primary endpoint was 28-day all-cause in-hospital mortality and the secondary outcome was transfer to the ICU. Results. The study included 125 patients. The primary outcome was observed in 44.8% of them: 27% in the baricitinib group vs. 62% in the SOC group, p < 0.001. Transfer to the ICU ward was significantly lower in the baricitinib group: 29% vs. 81%, p < 0.001. A significant improvement was observed when the baricitinib group was compared to SOC in procalcitonin, CRP, D-dimer, neutrophil-to-lymphocyte ratio values, and NEWS2. Conclusion. Treatment with baricitinib in addition to SOC was associated with reduced mortality and a lower prevalence of transfer to the ICU in hospitalized patients with COVID-19 pneumonia treated with high-flow oxygen non-invasive therapy.

A multi-subgroup predictive model based on clinical parameters and laboratory biomarkers to predict in-hospital outcomes of plasma exchange-centered artificial liver treatment in patients with hepatitis B virus-related acute-on-chronic liver failure

Background

Postoperative risk stratification is challenging in patients with hepatitis B virus-related acute-on-chronic liver failure (HBV-ACLF) who undergo artificial liver treatment. This study characterizes patients' clinical parameters and laboratory biomarkers with different in-hospital outcomes. The purpose was to establish a multi-subgroup combined predictive model and analyze its predictive capability.

Methods

We enrolled HBV-ACLF patients who received plasma exchange (PE)-centered artificial liver support system (ALSS) therapy from May 6, 2017, to April 6, 2022. There were 110 patients who died (the death group) and 110 propensity score-matched patients who achieved satisfactory outcomes (the survivor group). We compared baseline, before ALSS, after ALSS, and change ratios of laboratory biomarkers. Outcome prediction models were established by generalized estimating equations (GEE). The discrimination was assessed using receiver operating characteristic analyses. Calibration plots compared the mean predicted probability and the mean observed outcome.

Results

We built a multi-subgroup predictive model (at admission; before ALSS; after ALSS; change ratio) to predict in-hospital outcomes of HBV-ACLF patients who received PE-centered ALSS. There were 110 patients with 363 ALSS sessions who survived and 110 who did not, and 363 ALSS sessions were analyzed. The univariate GEE models revealed that several parameters were independent risk factors. Clinical parameters and laboratory biomarkers were entered into the multivariate GEE model. The discriminative power of the multivariate GEE models was excellent, and calibration showed better agreement between the predicted and observed probabilities than the univariate models.

Conclusions

The multi-subgroup combined predictive model generated accurate prognostic information for patients undergoing HBV-ACLF patients who received PE-centered ALSS.

The Diagnostic Value of the Neutrophil-to-Lymphocyte Ratio and Platelet-to-Lymphocyte Ratio for Deep Venous Thrombosis: A Systematic Review and Meta-Analysis

The neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) are emerging tools that can be used in the diagnosis of deep venous thrombosis (DVT). This study aims to evaluate the diagnostic value of NLR and PLR for patients with DVT. Our meta-analysis included 11 eligible studies and extracted relevant diagnostic indicators. Of these studies, 4 focused on the NLR, 1 on the PLR, while 6 evaluated both. For the 10 studies on NLR, the pooled sensitivity, specificity, positive-likelihood ratio, and negative-likelihood ratio were 74%, 66%, 2.16, and 0.4, respectively. The estimated diagnostic odds ratio (DOR) was 5.3, and the area under the curve (AUC) of the summary receiver operating characteristic (SROC) curves was 0.74. For the 7 studies on the PLR, the pooled sensitivity, specificity, positive-likelihood ratio, and negative-likelihood ratio were 0.65, 0.77, 2.89, and 0.45, respectively. The estimated DOR was 6.64, and the SROC-AUC was 0.79. Our findings showed that the NLR and PLR exhibit moderate diagnostic accuracy and may be helpful biomarkers for the diagnosis of DVT. Future prospective, well-designed studies with large sample sizes will be required to provide additional evidence to establish cutoff values and clinical value of these indicators.

COVID19 biomarkers: What did we learn from systematic reviews?

The coronavirus disease 2019 (COVID19) pandemic continues to represent a substantial public health concern. It can rapidly progress to severe disease, with poor prognosis and a high mortality risk. An early diagnosis and specific prognostic tools can help healthcare providers to start interventions promptly, understand the likely prognosis and to identify and treat timely individuals likely to develop severe disease with enhanced mortality risk. Here we focused on an impressive set of systematic reviews and meta-analyses that were performed since the start of the COVID19 pandemic and summarized their results related to the levels of hematologic, inflammatory, immunologic biomarkers as well as markers of cardiac, respiratory, hepatic, gastrointestinal and renal systems and their association with the disease progression, severity and mortality. The evidence outlines the significance of specific biomarkers, including inflammatory and immunological parameters (C-reactive protein, procalcitonin, interleukin-6), hematological (lymphocytes count, neutrophil-to-lymphocyte ratio, D-dimer, ferritin, red blood cell distribution width), cardiac (troponin, CK-MB, myoglobin), liver (AST, ALT, total bilirubin, albumin) and lung injury (Krebs von den Lungen-6) that can be used as prognostic biomarkers to aid the identification of high-risk patients and the prediction of serious outcomes, including mortality, in COVID19. Thus, these parameters should be used as essential tools for an early risk stratification and adequate intervention in improving disease outcomes in COVID19 patients.

Evaluating the neutrophil-to-lymphocyte ratio as an indicator for early referral of patients with COVID-19 pneumonia to a high-care facility

BACKGROUND

Early identification of patients at high risk of severe disease requiring referral and treatment at a high-care facility is imperative in the management of COVID-19 pneumonia in a limited-resource setting, as transfer of unstable patients can be detrimental.

OBJECTIVES

To examine the value of the neutrophil-to-lymphocyte ratio (NLR) calculated on admission to a healthcare facility as a predictor of the need for early referral to a high-care facility for further treatment.

METHODS

We designed a cohort analytical study of 198 patients with COVID-19 pneumonia admitted to the COVID-19 unit at Universitas Academic Hospital in Bloemfontein, South Africa, between 20 May and 30 September 2021.

RESULTS

Of the 198 patients enrolled in the study, 134 (67.7%) were admitted to high care and 93 (46.9%) died. The median (interquartile range (IQR)) NLR measured on admission to the hospital was 8.09 (4.90 - 14.86), and the NLR ranged from 0.26 to 136.7. The admission NLR was statistically significantly higher in the high-care group v. the general ward group (p<0.001). After converting the NLR to log scale, to bring it closer to conditional normality, logistic regression analysis identified log NLR (odds ratio (OR) 4.089; 95% confidence interval (CI) 2.464 - 6.787; p<0.001) and age (OR 1.029; 95% CI 1.004 - 1.056; p=0.024) as significant in determining who will require high care. The area under the receiver operating characteristic curve for the combined model of NLR and age was 0.829 (95% CI 0.767 - 0.891). An NLR cut-off value of 7.5 (sensitivity 0.7462, specificity 0.7968) has been calculated as the optimal cut-off value to determine who will need high care. Admission log NLR and age were significant in determining who died (OR 2.067; 95% CI 1.404 - 3.045; p<0.001, and OR 1.043; 95% CI 1.018 - 1.068; p=0.001, respectively).

CONCLUSION

The NLR measured on admission and age can be used to predict whether a patient with COVID-19 pneumonia will require high care.

Comparison of clinical characteristics and outcome in RT-PCR positive and false-negative RT-PCR for COVID-19: A Retrospective analysis

Cases with SARS-CoV-2 RT-PCR negative pneumonia are an understudied group with uncertainty remaining regarding their treatment approach. We aimed to compare the clinical and radiological characteristics of RT-PCR positive and clinically diagnosed RT-PCR negative COVID-19. This was a single-centre retrospective study conducted at a tertiary care hospital in Western India. All patients (age ≥18 years) with suspicion of COVID-19 with SARI (severe acute respiratory infections) who were subjected to RT-PCR testing (nasal/oropharyngeal swab) were included. Based on RTPCR results, patients were categorized and compared for demographic, clinical, and biochemical characteristics and outcomes. Out of 500 patients, 339 (67.8%) found RT-PCR positive. Except for the radiological findings, both groups differ in clinical presentation, disease severity (inflammatory markers), and outcome. RT-PCR-positive patients had raised ferritin, NLR (Neutrophil-Lymphocyte ratio), LDH, and high mortality compared to the swab-negative group. In-hospital mortality was also significantly high in RT-PCR positive group (HR=1.9, 95% CI=1.4-2.5, p=0.001). On multivariate analysis, NLR, ferritin, and d-dimer were the independent predictors of mortality in RT-PCR-positive (p=0.038, 0.054, and 0.023). At the same time, raised TLC (total leukocyte count) and procalcitonin were the risk factors for poor outcomes in RT-PCR-negative patients (p=0.041 and 0.038). We found significantly raised ferritin, NLR, and LDH levels and increased mortality in RT-PCR positive patients compared to RT-PCR negative. Incorporating clinical features, radiological, and biochemical parameters could be prudent while managing the RT-PCR-negative patients.

Neutrophil-to-Lymphocyte Ratio and Cut-off Values as Predictor of Severity and Mortality in COVID-19 Patients in Millennium COVID-19 Care Center, Addis Ababa, Ethiopia

Background

Early identification of patients at high risk of poor clinical outcomes is the key to success in saving the lives of patients with coronavirus disease 2019 (COVID-19). Neutrophil to Lymphocyte Ratio (NLR) is an easily available and cheap surrogate inflammatory marker, its baseline NLR role in African COVID-19 patients remains to be investigated. The objective of the study aimed to evaluate the role of NLR as a predictor of severity and mortality of COVID-19 patients admitted at the Millennium COVID 19 care center in Addis Ababa, Ethiopia.

Methods

A cross-sectional study was conducted on patients with COVID-19 admitted to the Millennium COVID-19 care center from August 1 to October 30, 2021. Receiver Operating Characteristic curve analysis was used to calculate the area under the curve to assess the predictive capacity of NLR on mortality and severity. Multivariable logistic regression analysis was done to identify the association between independent variables and disease outcomes with an Adjusted Odds Ratio (AOR), P-value, and 95% CI for AOR were used for testing significance.

Results

The NLR of 9.47 was identified as the optimal cut-off value for predicting mortality with a sensitivity of 88.7% and a specificity of 95.4% (Area Under the Curve (AUC):0.95, 95% CI 0.92-98; P<0.001) and the NLR of 5.86 was an effective threshold value in predicting the severity of disease with a sensitivity of 92.2% and a specificity of 75% (AUC:0.85, 95% CI 0.800-0.905; P<0.001). In multivariable logistic regression analysis, after adjusting for confounding factors, NLR of more than 9.47 and 5.86 was significantly associated with all-cause of in-hospital mortality (AOR=4.73, 95% CI, 1.19-33.68; P<0.02), and severity of disease (AOR=12.98, 95% CI 3.85-43.80; P=0.001), respectively.

Conclusion

NLR greater than 9.47 and 5.86 effectively predict mortality and severity of the disease, respectively. It provides an objective input for early decision-making in inpatient management especially in resources limited area.

Excessive neutrophil recruitment promotes typical T-helper 17 responses in Coronavirus disease 2019 patients

Coronavirus disease 2019 (COVID-19) is caused by a recently identified virus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and the disease is a pandemic. Although the hallmarks of severe COVID-19 have been established, the underlying mechanisms that promote severe pathology have not been thoroughly studied. A better understanding of the immune response in severe COVID-19 patients may help guide the development of therapeutic strategies and predict immuno-pathogenicity. This study was set to determine the lymphocyte and cytokine profiles associated with COVID-19 severity. A total of 43 hospitalised COVID-19 patients were recruited for the study and whole blood samples were drawn from each patient. Complete blood counts, lymphocyte subset profiles and C-reactive protein statuses of patients were determined. Cytometric bead array was performed to analyse the cytokine profiles of each patient. The demographic characteristics showed that the median age of the patients was 48.72 years, with an interquartile range from 40 to 60 years, and 69.77% of the patients were male. COVID-19 patients exhibited significantly low CD4⁺ lymphocyte expansion and leucocytosis augmented by elevated neutrophil and immature granulocytes. Stratification analysis revealed that reduced monocytes and elevated basophils and immature granulocytes are implicated in severe pathology. Additionally, cytokine results were noted to have significant incidences of interleukin 17A (IL-17A) expression associated with severe disease. Results from this study suggest that a systemic neutrophilic environment may preferentially skew CD4⁺ lymphocytes towards T-helper 17 and IL-17A promotion, thus, aggravating inflammation. Consequently, results from this study suggest broad activity immunomodulation and targeting neutrophils and blocking IL-17 production as therapeutic strategies against severe COVID-19.

The Neutrophil-to-Lymphocyte Ratio and the Platelet-to-Lymphocyte Ratio as Predictors of Mortality in Older Adults Hospitalized with COVID-19 in Peru

Background

The prognostic value of the neutrophil-lymphocyte ratio (NLR) and platelet-lymphocyte ratio (PLR) in patients with COVID-19 is rarely described in older adults. We aimed to estimate the prognostic value of NLR and PLR, determining the mortality of adults over 60 years of age hospitalized for COVID-19 in three hospitals in Peru from March to May 2020.

Methods

We performed a secondary analysis of data from a retrospective cohort carried out in Lambayeque, Peru, from March 18 to May 13, 2020. Older adults hospitalized for COVID-19 were included. The outcome variable was in-hospital mortality by all causes, while the exposure variable was the NLR and PLR (categorized in tertiles and numerically, performing a logarithmic transformation). We included sociodemographic variables, comorbidities, vital functions, laboratory markers, and treatment received during hospital stay. We evaluated the association between NLR and PLR using the hazard ratio (HR) in a Cox regression model. We estimated HR with their respective 95% confidence intervals (95% CI). We estimated cumulative/dynamic time-dependent ROC curves and reported area under the curve ROC (AUC-ROC) for 15-, 30-, and 60-day mortality with their respective simultaneous confidence intervals (confidence bands (CB)). Also, we estimated an optimal cut-off point based on the maximally selected rank statistics.

Results

A total of 262 hospitalized older adults were analyzed, 71.8% (n = 188) of whom were male with a median age of 70 years (interquartile range: 65-78). The mean NLR and PLR were 16.8 (95% CI: 14.9-18.7; SD: 15.5) and 50.3 (95% CI: 44.6-55.9; SD: 46.3), respectively. The mortality rate was 68.7% (95% CI: 62.7-74.3). The adjusted Cox regression analysis showed that the high NLR (adjusted HR (aHR) = 2.12; 95% CI: 1.43-3.14) and PLR (aHR = 1.90; 95% CI: 1.30-2.79) tertiles were associated with a higher risk of mortality. The maximum AUC-ROC values at 60 days of follow-up for NLR and PLR were 0.713 (95%CB: 0.627-0.800) and 0.697 (95%CB: 0.583-0.754), respectively.

Conclusions

The NLR and PLR are predictors of higher risk of mortality, and these results suggest that both could be reliable and practical markers for the identification of older adults at high risk of mortality by COVID-19. NLR and PLR have prognostic value, with an AUC greater than 0.5; however, by themselves, they are weak prognostic markers. It is important to carry out future studies incorporating these two markers into preexisting models or designing new ones considering them.

Soluble CD137 as a potential biomarker for severe COVID-19

Coronavirus disease 2019 (COVID-19) is a contagious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a highly pathogenic infection responsible for the world pandemic in 2020. COVID-19 is characterized by an increased number of critically ill patients with a high risk of health care system collapse. Therefore, the search for severity biomarkers and potential therapies is crucial. In this study, we evaluated SARS-CoV-2 -induced cytokines, cytokines receptors and growth factors profile, in critical COVID-19 patients admitted in intensive care unit (ICU) aiming to identify potential biomarkers and therapeutic targets. We designed a prospective study enrolling 62 adults with severe COVID-19 during the first two Brazilian COVID-19 waves (from May to July 2020 and December 2020 to May 2021), convenience samples recruitment in first 24 hours and then, every 4 days until day 20 of ICU admission from a tertiary hospital in São Paulo, Brazil. Controls were healthy blood donors. Whole blood was used to evaluate 17 cytokines, cytokines receptors and growth factors. Due to low mortality rate, we used the need of mechanical ventilation as primary endpoint. In our analysis, we found a different pattern in soluble CD137 (sCD137) in critically ill patients with COVID-19, with a direct relationship between increased levels and worse clinical outcome. sCD137 was related with increased risk of mechanical ventilation and World Health Organization (WHO) clinical score for disease severity. CD137 is a tumor necrosis factor receptor (TNF) family member, mainly responsible for T-cell activation. Soluble isoforms of immune checkpoints competitively regulate function of their membrane-bound counterparts. Our study demonstrated the onward increase in sCD137 levels during severe SARS-CoV-2 infection and its correlation with worse outcomes, suggesting sCD137 as a potential reliable severity biomarker.

The effects of curcumin as dietary supplement for patients with COVID-19: A systematic review of randomized clinical trials

Accumulating evidence has been reported regarding the effect of curcumin as a dietary antiviral on patients with COVID-19; however, findings are controversial. Our systematic review aimed to evaluate the effects of curcumin in patients with COVID-19. Electronic databases (PubMed, EMBASE, Scopus, Web of Science, Cochrane Central, and Google Scholar) were systematically searched to identify only randomized clinical trials (RCTs) that assessed curcumin in patients with COVID-19 from inception to September 23, 2021 relevant keywords. The Cochrane risk-of-bias tool for randomized trials was used to evaluate the risk of bias. After a critical review of 1,098 search hits, only six RCTs were selected for discussion. A total of 480 patients were included, with 240 amongst the curcumin groups and 240 in the control group. The lymphocyte count was significantly higher in the curcumin group compared to the placebo group. Curcumin was found to decrease the number of T-helper 17 cells, downregulate T-helper-17 cell-related factors, reduce levels of T-helper-17 cell-related cytokines, yet increase the gene expression of Treg transcription factor forkhead box P3 (FOXP3), and decrease T-Box transcription factor 21 (TBX21). Our review revealed that curcumin might have a positive effect on relieving COVID-19 related inflammatory response due to its powerful immune-modulatory effects on cytokines production, T-cell responses, and gene expression. These findings suggest that curcumin confers clinical benefits in patients with COVID-19. However, due to the limited number of the included studies, further high-quality studies are needed to establish the clinical efficacy of the curcumin.

Inflawell® improves neutrophil-to-lymphocyte ratio and shortens hospitalization in patients with moderate COVID-19, in a randomized double-blind placebo-controlled clinical trial

Aims

COVID-19 is a significant global threat to public health. Despite the availability of vaccines and anti-viral drugs, there is an urgent need for alternative treatments to help prevent and/or manage COVID-19 symptoms and the underlying dysregulated immune response. We hypothesized that administration of Inflawell^® syrup, a Boswellia extract formulation enriched for boswellic acids (BAs), can reduce the excessive or persistent inflammation and thereby prevent disease progression. BAs are medicinally activated triterpenoids found in the resins of Boswellia spp., and possess an immense therapeutic potential due to their anti-inflammatory and immunoregulatory activities. We investigated the effect of Inflawell^® syrup, on moderate COVID-19 patients along with the current standard of care treatment.

Methods

A randomized placebo-controlled double-blind clinical trial was conducted, following definitive confirmation of COVID-19. Forty-seven hospitalized patients with moderate COVID-19 were enrolled and received either the Inflawell^® syrup or placebo. Clinical symptoms and markers of inflammation were evaluated at baseline and completion of the trial.

Results

Our clinical trial revealed an increase in the percentage of oxygen saturation level in patients that received the BAs compared to placebo (P < 0.0001). In addition, the average duration of hospitalization was significantly shorter in the BAs group compared with the placebo group (P < 0.04). Concomitantly, some improvement in the clinical symptoms including cough, dyspnea, myalgia, headache, and olfactory and gustatory dysfunction were detected in the BAs group. Hematologic findings showed a significant decrease in the percentage of neutrophils (P < 0.006) and neutrophil-to-lymphocyte ratio (NLR) levels (P < 0.003), associated with a significant increase in the percentage of lymphocytes in the BAs group compared with the placebo (P < 0.002). Additionally, a significant decrease in CRP, LDH, IL − 6 and TNF − α levels was detected in the BAs group. Following the intervention, fewer patients in the BAs group were PCR-positive for COVID-19 compared to placebo, though not statistically significant.

Conclusion

Overall, the treatment with Inflawell^® resulted in shorter hospital stay, alleviation of COVID-19 clinical symptoms and decline in the level of pro-inflammatory cytokines.

Trial registration

The trial has been registered in https://www.irct.ir with unique identifier: IRCT20170315033086N10 (https://en.irct.ir/trial/51631). IRCT is a primary registry in the WHO registry network (https://www.who.int/clinical-trials-registry-platform/network/primary-registries).

Cross-Sectional and Time-Dependent Analyses on Inflammatory Markers Following Natural Killer Cell Activity

The function of natural killer (NK) cells in inflammation has not been explored enough in large-scale population studies. The cross-sectional and time-dependent relationship between NK cell activity (NKA) and inflammatory markers was examined. Methods: A total of 7031 subjects were involved in the cross-sectional analyses. Non-linear relationship between NKA and inflammatory indices was analyzed using generalized additive models. The time-dependent changes were analyzed in 1005 subjects with repeated measurement in 3–6 months. The changes in inflammatory markers were analyzed based on the changes in NKA. Results: As NKA reduces to a very low level, the white blood cell (WBC) and neutrophil counts increase sharply, and the lymphocyte count exhibits a slow decline. With increasing NKA larger than about 500 pg/mL, WBC and neutrophil-lymphocyte ratio (NLR) reduces in a mild slope. Among the subjects with repeated measurements, the follow-up NKA was increased with advancing baseline NKA levels. The subjects with a reduction in NKA indicated increment in WBC count, neutrophil count, and NLR, and decrease in lymphocyte count. Conclusions: Very low levels of NKA suggest a high inflammatory immune response. The changes in NKA may interact with the balance between neutrophils and lymphocytes.

Neutrophils-to-Lymphocyte Ratio Is Associated with Progression and Overall Survival in Amyotrophic Lateral Sclerosis

Background: Amyotrophic lateral sclerosis (ALS) is a devastating and untreatable motor neuron disease, with a 3–5-year survival from diagnosis. Possible prognostic serum biomarkers include albumin, C-reactive protein, ferritin, creatinine, uric acid, hemoglobin, potassium, sodium, calcium, glucose, and the neutrophil-to-lymphocyte ratio (NLR), a marker of subclinical inflammation. Objective: To ascertain the influence of NLR on ALS progression rate and survival. Methods: Cross-sectional multicenter study including 146 consecutive incident and prevalent patients (88 males), aged >18 years, diagnosed according to the El Escorial criteria. The exclusion criteria were: (1) patients with tracheostomy or receiving mechanical ventilation; (2) patients with percutaneous endoscopic gastrostomy; and (3) patients who did not sign the informed consent. The rate of disease progression (ΔFS score) represents the monthly decline of the ALSFRS-R score, and was computed as (48 − total ALSFRS-R at recruitment)/symptom duration in months. Patients were followed up to tracheotomy, death, or the end of the follow-up, whichever occurred first. To validate our findings, we used data retrieved from the Pooled Resource Open-Access ALS Clinical Trials (PRO-ACT) Database. Results: The median disease duration was 15 (range = 2–30) months. The mean ALSFRS-R score at recruitment was 35.8 ± 8.0 (range: 10–48), and the median ΔFS was 0.66 (range: 0–5.33). Age at onset, at diagnosis, and at recruitment were significantly lower in the lowest NLR tertile. NLR values positively correlated with ΔFS values (r = 0.28): the regression slope of NLR (log-values) was 0.60 (p < 0.001) before and 0.49 (p = 0.006) after adjustment for age at recruitment. The ΔFS score progressively increased from the lowest to the highest NLR tertile: 0.35 (IQR: 0.18–0.93), 0.62 (IQR: 0.25–1.09), and 0.86 (IQR: 0.53–1.92). Patients were followed for a median of 2 years. The mortality rate passed from 15.9 events per 100 person-years in patients belonging to the lowest NLR tertile to 52.8 in those in the highest tertile. The optimal cut-off value which best classified patients with the lowest and the highest mortality rate was set at the NLR value of 2.315. Indeed, the mortality rate of patients with an NLR value above such cut-off was twice the mortality rate of patients with a value below the cut-off (age adjusted hazard ratio (HR): 2.16, 95% confidence interval (CI): 1.32–3.53). In the PRO-ACT validation sample, patients with an NLR value above the cut-off consistently had a higher mortality rate than those with a value below the cut-off (age adjusted HR: 1.17, 95%CI: 1.01–1.35). Conclusions: NLR could be a candidate easy, fast, and low-cost marker of disease progression and survival in ALS. It may be associated with low-grade inflammation either as a direct mirror of the pathological process of disease progression, or as a consequence of neuronal death (reverse causation). However, prospective studies are needed to understand whether NLR changes during the course of the disease, before using it to monitor disease progression in ALS.

The impact of opioid exposure during pregnancy on the human neonatal immune profile

BACKGROUND

The increasing magnitude of the opioid crisis and rising rates of neonatal abstinence syndrome (NAS) diagnoses highlight the need for increased research into how maternal substance use during pregnancy can impact the neonatal immune profile and its functionality. We hypothesized that neonates with opioid exposure would have reduced proportions of some immune cells, an anti-inflammatory cytokine profile, reduced T cell proliferation, and monocyte bacterial killing activity compared to the control population.

METHODS

The present study compares immune cell populations, inflammatory and anti-inflammatory cytokine and chemokine levels in the serum, and monocyte and T cell functional activity using umbilical cord samples from neonates with known opioid exposure during gestation and from control neonates without known exposure.

RESULTS

Our findings demonstrated a significant reduction in neutrophils, decreased levels of inflammatory cytokines in the serum, and reduced IL-2 production during in vitro CD4⁺ T cell proliferation in neonates exposed to opioids compared to controls. The neutrophil findings were supported by retrospective analysis of an extended network of deidentified patient records.

CONCLUSIONS

This study is the first of its kind to evaluate differences in neonatal immunity as a result of opioid exposure in the human population that will inform continued mechanistic studies.

IMPACT

The opioid epidemic has become a public health crisis in the United States, and the corresponding incidence of neonatal abstinence syndrome (NAS) have risen accordingly. New research is required to understand the short and long-term health impacts of opioid exposure to the neonate. This is the first human study to investigate the immunologic profile and functionality in neonates with known opioid exposure in utero. The abundance of neutrophils and the ratio of neutrophils to lymphocytes is significantly reduced along with inflammatory cytokines and chemokines following opioid exposure during pregnancy. The immune profile in opioid-exposed neonates may promote susceptibility to infection.

The predictive and prognostic role of hematologic and biochemical parameters in the emergency department among coronavirus disease 2019 patients

Coronavirus disease 2019 (COVID-19) had caused a worldwide pandemic with public health emergencies since 2020. For the symptomatic patients, high mortality rate was observed if without timely and optimized management. In this study, we aimed to investigate the predictive and prognostic roles of hematologic and biochemical parameters obtained in the emergency department (ED) for COVID-19 patients. We conducted a retrospective study in a dedicated COVID-19 medical center, recruiting a total of 228 COVID-19 patients with 86 severe and 142 non-severe cases. Both the hematologic and biochemical parameters obtained in the ED upon arrival were analyzed to evaluate the association of the biomarkers with disease severity and prognosis among COVID-19 patients. Among these parameters, neutrophil-to-lymphocyte ratio (NLR), C-reactive protein (CRP), procalcitonin (PCT), lactate dehydrogenase (LDH), ferritin, and D-dimer were significantly higher in the severe group than the non-severe one, whereas the platelet count and lymphocyte-to-monocyte ratio were significantly lower. Receiver operating characteristic curve analysis revealed that the areas under curve of CRP, PCT, LDH, ferritin, D-dimer, and NLR for differentiating the severity of COVID-19 were 0.713, 0.755, 0.763, 0.741, 0.733, and 0.683, respectively, whereas the areas under curve of CRP, PCT, LDH, ferritin, D-dimer, and NLR for differentiating the mortality of COVID-19 were 0.678, 0.744, 0.680, 0.676, 0.755, and 0.572, respectively. Logistic regression analysis revealed that CRP, PCT, LDH, ferritin, D-dimer, and NLR were independent indicators for prediction of severe COVID-19, and LDH and ferritin were independent factors associated with the mortality in COVID-19. In conclusion, higher CRP, PCT, LDH, ferritin, D-dimer, and NLR were associated with severe COVID-19, whereas higher LDH and ferritin were associated with the mortality in COVID-19. These findings could help early risk stratification in the ED and contribute to optimized patient management.

Low free-T3 serum levels and prognosis of COVID-19: systematic review and meta-analysis

OBJECTIVES

There is increasing interest regarding the relationship between serum levels of free triiodothyronine (fT3) and outcomes of COronaVIrus Disease-19 (COVID-19) patients. As several recent reports have described a worse prognosis in patients with low fT3 levels, we performed a meta-analysis to assess the prognostic role of fT3 serum levels in patients with COVID-19 as this information could be clinically relevant for the management of these patients.

METHODS

The methodology was registered in the International prospective register of systematic reviews (PROSPERO) database under the protocol number CRD42021260952. A systematic search was carried out on PubMed, Embase, Web of Science, and Scopus from May to June 2021 without time and language restrictions. The literature search strategy was based on the following keywords: (T3 OR fT3 OR triiodothyronine) AND (COVID-19) AND (prognosis OR survival).

RESULTS

The literature search identified 163 studies. Seven retrospective studies met the inclusion and exclusion criteria and were included in the meta-analysis. The included studies had a total of 1,183 patients. From the analysis of the included studies, lower fT3 serum levels were consistently observed in intensive care unit (ICU) than in non-ICU patients and in non-survivors than survivors, respectively.

CONCLUSIONS

Serum fT3 concentrations are significantly lower in patients with severe COVID-19 than in non-severely ill patients and predict all-cause mortality of patients with severe COVID-19. Accordingly, fT3 may become a simple tool for stratified management of patients with severe COVID-19.