Neutrophil-to-lymphocyte ratio as a prognostic marker in acute respiratory distress syndrome patients: a retrospective study

The Clinical significance of Peripheral Blood-related Inflammatory Markers in patients with AECOPD

OBJECTIVE

Peripheral blood-related inflammatory markers, including systemic immune inflammation index (SII), inflammatory response index (SIRI), neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and monocyte-to-lymphocyte ratio (MLR), have received increasing clinical attention over the years. This study aims to investigate the clinical significance of peripheral blood-related inflammatory markers in patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD). We hope that this study will provide guidance for clinical individualized treatment and management of AECOPD patients.

METHODS

A total of 254 patients with AECOPD admitted between January 2021 and December 2022 were enrolled in this study and categorized into mild and moderate-to-severe groups. Univariate analysis, Spearman correlation analysis, and receiver operating characteristic curve (ROC) were performed to study the clinical value of peripheral blood-related inflammatory markers. Then, the relationship between the peripheral blood-related inflammatory markers and the risk of readmission owing to acute exacerbation during the first year after discharge was further studied through survival analysis and multivariate Cox regression.

RESULTS

The levels of peripheral blood-related inflammatory markers in patients with moderate-to-severe AECOPD were significantly higher than patients in the mild group, and the levels of peripheral blood-related inflammatory markers are positively correlated with the severity of disease. The highest diagnostic accuracy for moderate-to-severe AECOPD was achieved by combining five indexes, with a cut-off value of 0.38 and an AUC of 0.837 (95 % CI: 0.789-0.885). Higher levels of peripheral blood-related inflammatory markers may indicate a higher risk of readmission within one year of hospital discharge in patients with AECOPD, and SII (HR = 3.478, P < 0.001) was an independent risk factor. Besides, higher levels of peripheral blood-related inflammatory markers also suggest impaired pulmonary ventilation function and enlarged right ventricular diameter.

CONCLUSIONS

Peripheral blood-related inflammatory markers (SII, SIRI, NLR, PLR, MLR) can serve as a reference for identifying patients with moderate-to-severe AECOPD. Patients with higher levels of peripheral blood-related inflammatory markers are more susceptible to experiencing acute exacerbation and readmission events within one year after hospital discharge. Peripheral blood-related inflammatory markers can assist clinicians in evaluating the condition and predicting the risk of readmission in patients with AECOPD more scientifically and objectively.

Epidemiology, clinical features and prognostic factors in patients with Covid-19 and acute limb ischaemia - A single center study

BACKGROUND

The aim of this study was to determine the incidence, clinical and paraclinical characteristics and outcomes of Covid-19 positive patients presenting in the Emergency Department (ED) with and treated for acute limb ischaemia (ALI) during a 2-year period.

METHODS

This retrospective study was conducted in the ED of St. Spiridon County Clinical Emergency Hospital in Iasi, north-east region of Romania. The patients included in this study presented in the ED between March 1st, 2020 and February 28th, 2022 with ALI and Covid-19.

RESULTS

During the study period, a total number of 141018 patients were evaluated in our ED, 8578 (representing 6,08%) patients being diagnosed with Covid-19. Of them, 98 (1.14% of all with Covid-19) presented ALI. The mean age was 70.9 ± 10.23 and 67.3% of the patients were males. At admission, 57% of patients had Covid-19-related pneumonia, identified on X-ray or CT scan. Of all patients, 81 (82%) were diagnosed with ALI in lower limbs with 10% of them having affected both limbs. 95% of the patients presented comorbidities, the main being cardiac (85%), diabetes mellitus (37%), vascular (24%) and neurological (22.6%). Non-survivor patients were more likely to have Covid-19 pneumonia on chest X-ray or CT scan, 92% versus 44% (OR 15, CI 3.3; 68, p < .01), lymphopenia 96% versus 70% (OR 10.2, CI 1.30; 80.9, p < .01), a NLR over 9.77% versus 30% (OR 7.5, CI 2.6; 21.4, p < .01), acidosis 65% versus 33% (OR 3.8, CI 1.4; 9.7, p < .01), abnormal AST, 69% versus 29% (OR 5.4, CI 2; 14.5, p < .01) and secondary amputation, 38.5 versus 11.1% (OR 5, CI 1.7; 14.7, p < 0.1). Overall, the mortality rate was 26.5%.

CONCLUSION

The prevalence of ALI in patients infected with Covid-19 who were evaluated in our ED was 1.14%. The highest mortality rate was probably related to Covid-19 pneumonia. We observed that patients with Covid-19 pneumonia, lymphopenia, a NLR >9, metabolic acidosis, increased AST at ED admission and secondary amputation had a higher mortality.

A study of changes in hematologic parameters in patients with migraine

INTRODUCTION

To evaluate the characteristics of hematological parameters and peripheral inflammatory markers (PIMs) in migraine, including chronic migraine (CM) and episodic migraine (EM), and to explore their underlying mechanisms.

METHOD

A total of 88 subjects were enrolled, 58 with migraine (28 with CM and 30 with EM) and 30 healthy controls. All subjects were matched for age, gender, and body mass index, and peripheral blood was collected. Hematological parameters and PIMs were compared between migraineurs and healthy controls. The patients underwent hematological laboratory testing and calculated the PIMs. PIMs included neutrophil/lymphocyte ratio, lymphocyte/monocyte ratio (LMR), neutrophil/monocyte ratio, platelet/lymphocyte ratio, and platelet/monocyte ratio (PMR) ratio.

RESULT

Monocyte counts in migraine patients were significantly lower compared with healthy controls, while LMR and PMR were significantly higher. Statistically significant differences were observed in monocyte counts, LMR, and PMR among the three groups of CM, EM, and HC patients. Post hoc Bonferroni t-test showed that monocyte counts were significantly lower in the EM group compared with the HC group, while LMR and PMR were significantly higher. Comparison between the EM and CM groups showed that LMR was significantly higher in the EM group. Differences in monocyte counts, LMR, and PMR between the CM and HC groups were not statistically significant. Receiver operating characteristic curve analysis indicated that the area under the curve (AUC) for the diagnosing migraine using the combination of Mon, LMR, and PMR was 0.707, and the AUC for the diagnosis of EM was 0.758. The AUC value of PMR for diagnosing CM was 0.669, while the AUC for the combination of LMR and platelet/lymphocyte ratio in distinguishing CM and EM was 0.705.

CONCLUSION

Our findings indicate that migraine and its subtypes exhibit abnormalities in monocyte counts and PIMs, which possess diagnostic predictive value for differentiating migraine and its subtypes. This suggests that systemic inflammation may play a role in the pathogenesis of migraine.

Hemogram-Based Phenotypes of the Immune Response and Coagulopathy in Blunt Thoracic Trauma

Background: Blunt thoracic trauma possesses unique physiopathological traits due to the complex interaction of immune and coagulation systems in the lung tissue. Hemogram-based ratios such as neutrophil-to-lymphocyte (NLR), platelet-to-lymphocyte (PLR), neutrophil-to-lymphocyte × platelet (NLPR) ratios have been studied as proxies for immune dysregulation and survival in trauma. We hypothesized that blunt thoracic trauma patients exhibit distinct patterns of coagulation and inflammation abnormalities identifiable by the use of readily available hemogram-derived markers. Methods: The present study represents a retrospective observational analysis that included 86 patients with blunt thoracic trauma from a single high-volume level one trauma center. The primary outcome was mortality prediction in blunt thoracic trauma patients using these derived biomarkers. Secondary outcomes included phenotypes of the immune response and coagulopathy and the prediction of non-fatal adverse events. Results: A U-shaped distribution of mortality was found, with high rates of early deaths in patients with an NLPR value of <3.1 and high rates of late deaths in patients with NLPR > 9.5. A subgroup of blunt thoracic trauma patients expressing moderate inflammation and inflammation-induced hypercoagulation objectified as NLPR between 3.1 and 9.5 may have a survival benefit (p < 0.0001). The NLPR cut-off for predicting early deaths and the need for massive transfusion was 3.1 (sensitivity = 80.00% and specificity = 71.05%). Conclusions: These findings suggest that blunt thoracic trauma patients exhibit distinct phenotypes of the immune response and coagulopathy from the early stages. A controlled, balanced interaction of immune, coagulation, and fibrinolytic systems might effectively achieve tissue repair and increase survival in thoracic trauma patients and should be subject to further research.

Neutrophil-to-lymphocyte ratio as a prognostic biomarker in patients with peripheral artery disease: A systematic review and meta-analysis

BACKGROUND

The neutrophil-to-lymphocyte ratio (NLR) is a simple and routinely obtained parameter reflecting systemic inflammation, including in peripheral artery disease (PAD).

METHODS

This systematic review aimed to assess the role of NLR as a prognostic biomarker in patients with PAD. A systematic search was conducted across PubMed, ScienceDirect, Web of Science, Scopus, ProQuest, EBSCO, and Cochrane. Random-effects meta-analysis was used to pool risk ratios, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV). A bivariate model was used to generate summary receiver operating characteristics with the corresponding area under the curve (AUC).

RESULTS

This review included 5243 patients with PAD from nine eligible studies. High NLR corresponded to at least a twofold increased risk of all-cause mortality (ACM), major adverse limb events (MALE), and major adverse cardiovascular events (MACE). NLR's performance was good for predicting 1-year ACM (AUC 0.71 [95% CI: 0.59-0.79], sensitivity 58.2% [95% CI: 45.3-71.0], specificity 72.6% [95% CI: 65.6-79.62], PPV 41.0% [95% CI: 31.2-50.7], NPV 82.7% [95% CI: 74.1-91.3]) and 1-year MALE (AUC 0.78 [95% CI: 0.75-0.80], sensitivity 65.4% [95% CI: 41.6-89.2], specificity 77.7% [95% CI: 71.0-84.3], PPV 53.7% [95% CI: 47.3-60.1], NPV 83.91% [95% CI: 73.2-94.6]). However, these values tended to decrease as the follow-up duration extended, except for the pooled specificities, which exhibited the opposite pattern.

CONCLUSION

NLR emerges as a simple and cost-effective prognostic biomarker with decent performance for poor outcomes in patients with PAD (PROSPERO Registration No.: CRD42023486607).

Admission neutrophil-to-lymphocyte ratio to predict mortality in burn patients: a meta-analysis

BACKGROUND

The neutrophil-to-lymphocyte ratio (NLR) proves to be a convenient and cost-effective marker with studies showing that a high NLR can serve as a mortality indicator in burn cases. We conducted a meta-analysis aiming to explore whether on-admission NLR values could serve as predictors of mortality in burn patients.

METHODS

PubMed, Web of Science, Scopus and Embase were searched from inception until January 2024. We included all studies investigating burn patients that contain information on the NLR value at the time of hospital admission and mortality outcomes. The studies were critically appraised using the NIH Quality Assessment Tool.

RESULTS

Nine studies fulfilled our criteria with a total population of 1837 participants, including 1526 survivor Burn patients and 311 non-survivor Burn patients. The overall mean difference measured by random model showed a significant increase in NLR by 5.06 (95% CI 3.42, 6.68) p ≤ 0.001 for the non-survivor group over the survivors group with heterogeneity I2 = 67.33%, p ≤ 0.001. A meta-regression was done to investigate the potential source of heterogeneity among studies. The results showed that age (p = 0.394), gender (p = 0.164), and sample size (p = 0.099) did not contribute to the source of heterogeneity, however, the burn surface area contributed significantly (p = 0.002). A leave-one-out meta-analysis was done, showing that omitting Le Qui et al., leads to significantly decrease the heterogeneity to be I2 = 2.73%. Meta-regression repeated to assess the burn surface area again to be found noncontributing (p = 0.404).

CONCLUSIONS

Our findings support that elevated NLR values can serve as a mortality indicator in burn cases. This will have a great clinical impact by aiding in stratifying the burn patients on admission.

Maternal prenatal systemic inflammation indexes predicts premature neonatal respiratory distress syndrome

Neonatal respiratory distress syndrome (NRDS) is one of the leading causes of neonatal mortality in low-income countries. It is caused by a lack of surface-active substances in the lungs, and the maternal inflammatory response plays an important role in the formation of surface-active substances in the fetal lungs. We aimed to investigate the correlation between maternal prenatal systemic inflammatory indices and respiratory distress syndrome in preterm neonates. This is a retrospective case-control study that collected data from all patients who delivered between 28 and 36 weeks of gestation at Longhua District People's Hospital in Shenzhen City and whose infants were admitted to the neonatal unit, newborns with respiratory distress syndrome were in the experimental group (NRDS group), and newborns without NRDS were in the control group (non-NRDS group). To minimize the effect of confounders on the results, propensity score matching was performed on baseline characteristics. Totally, 524 patients were included (93 in the NRDS group and 431 in the non-NRDS group), and 71 matched pairs (142 patients). The neutrophil-to-lymphocyte ratio (NLR), derived neutrophil-to-lymphocyte ratio (dNLR), systemic immune-inflammation index (SII), systemic inflammation response index (SIRI), aggregate index of systemic inflammation (AISI) and neutrophil lymphocyte to platelet ratio (NLPR) were higher in the NRDS group than in the non-NRDS group (p < 0.05). The ROC curves of NLR, dNLR, SII, SIRI, AISI and NLPR for the diagnosis of NRDS were plotted, and it was found that the combined diagnostic efficacy of these six systemic inflammatory markers was better (AUC: 0.643, P = 0.003). Patients were divided into two groups based on the cut-off values determined from the ROC curves, and analysis using binary regression models revealed that SII ≥ 1199.94 (OR, 2.554; 95% CI 1.245-5.239, P = 0.011) and NLPR ≥ 0.0239 (OR, 2.175; 95% CI 1.061-4.459, P = 0.034) were independent risk factors predicting NRDS. Maternal prenatal SII ≥ 1199.94 and NLPR ≥ 0.0239 are independent risk factors for NRDS, and clinicians may be used to prevent neonatal respiratory distress in advance to reduce the incidence of NRDS.

Clinical study of neutrophil-to-lymphocyte ratio and platelet-to-lymphocyte ratio in hypertriglyceridemia-induced acute pancreatitis and acute biliary pancreatitis with persistent organ failure

BACKGROUND

The neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) are novel inflammatory indicators that can be used to predict the severity and prognosis of various diseases. We categorize acute pancreatitis by etiology into acute biliary pancreatitis (ABP) and hypertriglyceridemia-induced acute pancreatitis (HTGP).

AIM

To investigate the clinical significance of NLR and PLR in assessing persistent organ failure (POF) in HTGP and ABP.

METHODS

A total of 1450 patients diagnosed with acute pancreatitis (AP) for the first time at Shanxi Bethune Hospital between January 2012 and January 2023 were enrolled. The patients were categorized into two groups according to the etiology of AP: ABP in 530 patients and HTGP in 241 patients. We collected and compared the clinical data of the patients, including NLR, PLR, and AP prognostic scoring systems, within 48 h of hospital admission.

RESULTS

The NLR (9.1 vs 6.9, P < 0.001) and PLR (203.1 vs 160.5, P < 0.001) were significantly higher in the ABP group than in the HTGP group. In the HTGP group, both NLR and PLR were significantly increased in patients with severe AP and those with a SOFA score ≥ 3. Likewise, in the ABP group, NLR and PLR were significantly elevated in patients with severe AP, modified computed tomography severity index score ≥ 4, Japanese Severity Score ≥ 3, and modified Marshall score ≥ 2. Moreover, NLR and PLR showed predictive value for the development of POF in both the ABP and HTGP groups.

CONCLUSION

NLR and PLR vary between ABP and HTGP, are strongly associated with AP prognostic scoring systems, and have predictive potential for the occurrence of POF in both ABP and HTGP.

Evaluation of the Effectiveness of Systemic Inflammatory Indices in the Diagnosis of Respiratory Distress Syndrome in Preterm with Gestational Age of ≤32 Weeks

OBJECTIVE

It is not yet known whether systemic inflammatory indices affect the development of respiratory distress syndrome (RDS) in premature infants. We aimed to evaluate the relationship between systemic inflammatory indices obtained on the first day of life and the development of RDS in premature infants.

STUDY DESIGN

Premature infants with gestational age of ≤32 weeks were included in the study. Six systemic inflammatory indices involving neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), monocyte-to-lymphocyte ratio (MLR), systemic immune-inflammation index (SII), pan-immune-inflammation value (PIV), and systemic inflammation response index (SIRI) were measured in the first 1 hour after birth and compared in premature infants with and without RDS.

RESULTS

A total of 931 premature infants, 579 infants in the RDS group and 352 infants in the non-RDS group, were included in the study. MLR, PLR, and SIRI values were similar between the groups (p > 0.05 for all parameters). NLR, PIV, and SII values in the RDS group were significantly higher than those in the non-RDS group (p = 0.005, p = 0.011, and p < 0.001, respectively). In the predictivity of RDS, the AUC value of SII was 0.842 and the cut-off value was ≥78.200. Multiple logistic analysis showed that a higher level of SII (≥78.2) was independently associated with RDS (odds ratio: 3.03, 95% confidence interval: 1.761-5.301).

CONCLUSION

Our results demonstrated that a higher SII level (≥78.2) may be a predictor for the development of RDS in premature infants with gestational age of ≤32 weeks.

KEY POINTS

· It is not yet known whether systemic inflammatory indices affect the development of RDS.. · Our results demonstrated high SII levels may be a predictor for the development of RDS.. · SII may provide an advantage as a low-cost, easy-to-detect, useful and powerful parameter in RDS..

Association of biomarkers with successful ventilatory weaning in COVID-19 patients: an observational study

OBJECTIVE

To evaluate the association of biomarkers with successful ventilatory weaning in COVID-19 patients.

METHODS

An observational, retrospective, and single-center study was conducted between March 2020 and April 2021. C-reactive protein, total lymphocytes, and the neutrophil/lymphocyte ratio were evaluated during attrition and extubation, and the variation in these biomarker values was measured. The primary outcome was successful extubation. ROC curves were drawn to find the best cutoff points for the biomarkers based on sensitivity and specificity. Statistical analysis was performed using logistic regression.

RESULTS

Of the 2,377 patients admitted to the intensive care unit, 458 were included in the analysis, 356 in the Successful Weaning Group and 102 in the Failure Group. The cutoff points found from the ROC curves were -62.4% for C-reactive protein, +45.7% for total lymphocytes, and -32.9% for neutrophil/lymphocyte ratio. These points were significantly associated with greater extubation success. In the multivariate analysis, only C-reactive protein variation remained statistically significant (OR 2.6; 95%CI 1.51 - 4.5; p < 0.001).

CONCLUSION

In this study, a decrease in C-reactive protein levels was associated with successful extubation in COVID-19 patients. Total lymphocytes and the neutrophil/lymphocyte ratio did not maintain the association after multivariate analysis. However, a decrease in C-reactive protein levels should not be used as a sole variable to identify COVID-19 patients suitable for weaning; as in our study, the area under the ROC curve demonstrated poor accuracy in discriminating extubation outcomes, with low sensitivity and specificity.

Physiological changes in captive elephants in northern Thailand as a result of the COVID-19 tourism ban-stress biomarkers

The international travel ban instituted by the Thai government in March 2020 in response to the COVID-19 pandemic greatly affected how tourist camp elephants were managed, with reductions in exercise opportunities, longer chaining hours, and diminished food provisioning. This study was conducted to determine how those changes affected health and welfare biomarkers in individual elephants over the 2 years of the countrywide lockdown (April 2020-April 2022). Blood and fecal samples were collected from 58 elephants at six camps (monthly in Year 1, quarterly in Year 2) and analyzed for stress biomarkers - fecal glucocorticoid metabolites (fGCM), serum oxidative stress [malondialdehyde (MDA) and 8-hydroxy-2'-deoxyguanosine (8-OHdG)], and stress leukograms. Overall, fGCM concentrations increased within the first few months and remained higher than pre-COVID levels, as did the H/L ratio, a measure affected by cortisol. Serum 8-OHdG, an indicator of DNA oxidative damage, also increased over time, while monocytosis and lymphopenia further suggested alterations in immune function as a result of stress. By contrast, another marker of oxidative stress, serum MDA, declined, possibly in response to reduced roughage and supplement intake. A notable finding was a seasonal pattern of fGCM that was significantly different from previous studies. Whereas higher fGCM during the rainy season were observed in this study, previously, concentrations were highest during the winter, high tourist season. Thus, ironically, both the presence and absence of tourists have been associated with increased fGCM concentrations, albeit for different reasons. Camp management factors negatively affecting stress outcomes included shorter chain lengths, longer chain hours, lack of exercise, and reduced roughage and supplements. Overall, it was clear that camps struggled to maintain adequate care for elephants during the COVID-19 pandemic, highlighting the importance of tourist income and need for contingency plans to cope with potential future disruptions to tourism.

Evaluation of red blood cell distribution width, neutrophil-to-lymphocyte ratio, and other hematologic parameters in canine acute pancreatitis

OBJECTIVE

To determine if RBC distribution width (RDW), neutrophil-to-lymphocyte ratio (NLR), and other hematological parameters are associated with increased odds of in-hospital mortality, increased length of hospitalization (LOH), or disease severity as measured by the Canine Acute Pancreatitis Severity (CAPS) score in dogs with acute pancreatitis (AP).

DESIGN

Retrospective, multicenter study from January 2016 to August 2020.

SETTING

Four private emergency and specialty referral centers.

ANIMALS

On initial case search, 118 client-owned dogs were identified with a clinical diagnosis of AP. Out of these cases, 114 dogs met inclusion criteria, defined as sudden onset of ≥2 compatible clinic signs (lethargy, anorexia, vomiting, or abdominal pain), a specific canine pancreatic lipase concentration >400 μg/L, hospital admission, as well as CBC and serum biochemistry run within 48 hours of initial hospitalization. Disease severity was calculated and measured using the CAPS score, in addition to LOH and in-hospital mortality.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Clinical endpoints were in-hospital mortality, LOH, and disease severity, as evaluated by the CAPS score. Overall in-hospital mortality was 36.8%. NLR was significantly associated with survival, with a higher percentage being associated with an increased likelihood of nonsurvival (odds ratio: 1.1, 95% confidence interval: 1.0-1.2; P = 0.006, adjusted P = 0.04). Increased NLR was found to be significantly associated with a longer LOH based on the unadjusted P-value (P = 0.02) but was not statistically significant based on a P-value adjusted for multiple comparisons (P = 0.12). No significant associations were noted when RDW, platelet-to-lymphocyte ratio, WBC count, mean platelet volume, RDW-to-platelet ratio, or RDW-to-total serum calcium ratio was evaluated against outcome measures.

CONCLUSIONS

This study retrospectively evaluated the prognostic utility of several readily available hematological parameters in dogs hospitalized for AP. Dogs with an increased NLR may have a higher risk of in-hospital mortality and increased LOH, although future prospective studies are necessary to confirm these findings.

Neutrophil-to-Lymphocyte Ratio: An Easy Marker for the Diagnosis and Monitoring of Inflammatory Bowel Disease in Children

BACKGROUND

The neutrophil-to-lymphocyte ratio (NLR) is a simple and inexpensive inflammation biomarker that reflects systemic inflammation based on complete blood count values.

AIMS

In our study, we aimed to compare the NLR values in pediatric inflammatory bowel disease (IBD) and in healthy controls, and to define NLR levels in children with IBD during diagnosis, active disease, and remission.

METHODS

NLR values of patients with IBD at diagnosis, remission, and active disease of the patients were recorded retrospectively. Age- and sex-matched healthy subjects enrolled as the control group.

RESULTS

Sixty-three patients with IBD and 92 healthy subjects as the control group enrolled. The mean age of the patients with IBD was 9.31 ± 5.24 years, and 57.1% were males. The mean NLR values of the patients with IBD at diagnosis and remission were significantly higher than that of healthy controls (p < 0.001). The mean NLR values of the patients at diagnosis and active disease were significantly higher than that of during remission (p < 0.001). The best cutoff of NLR for prediction of diagnosis of IBD in children was 1.46 with a sensitivity of 86.2% and specificity of 93.5%. There was no significant difference regarding NLR between patients with IBD with and without associated diseases. At diagnosis the mean NLR level of patients with Crohn's disease was significantly higher than that of ulcerative colitis (p = 0.019).

CONCLUSIONS

It was shown for the first time that NLR levels were significantly increased at diagnosis and active disease of childhood IBD, compared to the remission period. We believe that NLR can be a non-invasive inflammatory biomarker that should be used in the initial evaluation and follow-up of the disease activity in children.

The complex lipid, SPPCT-800, reduces lung damage, improves pulmonary function and decreases pro-inflammatory cytokines in the murine LPS-induced acute respiratory distress syndrome (ARDS) model

CONTEXT

Acute respiratory distress syndrome (ARDS) is a highly fatal, inflammatory condition of lungs with multiple causes. There is no adequate treatment.

OBJECTIVE

Using the murine LPS-induced ARDS model, we investigate SPPCT-800 (a complex lipid) as treatment for ARDS.

MATERIALS AND METHODS

C57B16/N mice received 50 μg of Escherichia coli O111:B4 lipopolysaccharide (LPS). SPPCT-800 was given as either: (1) 20 or 200 mg/kg dose 3 h after LPS; (2) 200 mg/kg (prophylactically) 30 min before LPS; or (3) eight 200 mg/kg treatments over 72 h. Controls received saline installations.

RESULTS

At 48 and 72 h, SpO₂ was 94% and 90% in controls compared to 97% and 94% in treated animals. Expiration times, at 24 and 48 h, were 160 and 137 msec for controls, but 139 and 107 msec with SPPCT-800. In BALF (24 h), cell counts were 4.7 × 10⁶ (controls) and 2.9 × 10⁶ (treated); protein levels were 1.5 mg (controls) and 0.4 mg (treated); and IL-6 was 942 ± 194 pg/mL (controls) versus 850 ± 212 pg/mL (treated) [at 72 h, 4664 ± 2591 pg/mL (controls) versus 276 ± 151 pg/mL (treated)]. Weight losses, at 48 and 72 h, were 20% and 18% (controls), but 14% and 8% (treated). Lung injury scores, at 24 and 72 h, were 1.4 and 3.0 (controls) and 0.3 and 2.2 (treated).

DISCUSSION AND CONCLUSIONS

SPPCT-800 was effective in reducing manifestations of ARDS. SPPCT-800 should be further investigated as therapy for ARDS, especially in longer duration or higher cumulative dose studies.

Regulatory T cells in inflammation and resolution of acute lung injury

Introduction

Acute respiratory distress syndrome (ARDS) is characterized by hypoxemia and increased lung permeability and would result in acute respiratory failure and with high mortality. In patients who survive from acute lung injury (ALI)/ARDS, it is an active process of the transition from injury to resolution depending on the coordinated immune system. The roles of regulatory CD4⁺T cells (Tregs) are now gradually being clarified during inflammation and resolution of ARDS. However, clear conclusions about roles of Tregs in ALI/ARDS are only a few.

Objective

This review provides an overview of phenotype, differentiation, and suppressive mechanisms of Tregs and focuses on keys of biology of Tregs in alveolar space during the inflammatory response and resolution of ALI/ARDS.

Data Source

Literature search of Web of Science, PubMed, and EMBASE was made to find relative articles about Tregs in ALI/ARDS. We used the following search terms: Tregs, ALI, ARDS, inflammation, and resolution.

Conclusion

More and more studies have indicated Tregs involved in the processes of inflammation and resolution of ALI/ARDS. A deep understanding of the roles of Tregs may indicate new treatments for patients of ARDS. Therapies aimed at expansion or adaptive transfer of Tregs could be an effective therapy to ARDS patients.

Using neutrophil to lymphocyte ratio to predict discharge among geriatric patients with influenza infection in emergency department

The neutrophil-to-lymphocyte ratio (NLR) is used to predict the prognosis of various diseases, such as coronavirus disease 2019, community-acquired pneumonia, bacteremia, and endocarditis. However, NLR has never been reported to predict patient discharge in geriatric patients with influenza infection. This retrospective case-control study enrolled geriatric patients (≥65 years) with influenza virus infection who visited the emergency department of a medical center between January 01, 2010 and December 31, 2015. Demographic data, vital signs, past histories, influenza subtypes, outcomes, and disposition were analyzed. The optimal NLR cut-off value to predict patient discharge was determined using the Youden index. We also evaluated the accuracy of NLR in predicting patient discharge using logistic regression and receiver operating characteristic analysis. The study included 409 geriatric patients in the emergency department with a mean age of 79.5 years and an approximately equal sex ratio. NLR was significantly lower in the discharged group than in the nondischarged group (5.8 ± 3.7 vs 9.7 ± 8.4). Logistic regression revealed that patients with NLR ≤ 6.5 predicted discharge with an odds ratio of 3.62. The Hosmer-Lemeshow goodness-of-fit test was calculated as 0.36, and the adjusted area under the receiver operating characteristic was 0.75. The negative predictive value of NLR ≤ 6.5, to predict patient discharge, was 91.8%. NLR ≤ 6.5 is a simple and easy-to-obtain laboratory tool to guide the physicians to discharge geriatric patients with influenza infection in the crowded emergency department.

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 is Associated with the Requirement and the Duration of Invasive Mechanical Ventilation in Acute Respiratory Distress Syndrome Patients: A Retrospective Study

Background

Acute respiratory distress syndrome (ARDS) is associated with high in-hospital mortality and most ARDS patients require ventilatory support. Applying appropriate ventilation strategies based on patients' individual situations has a direct impact upon patients' outcome. The neutrophil-to-lymphocyte ratio (NLR) has been shown to predict the early requirement of invasive mechanical ventilation (IMV) in patients with coronavirus disease 2019 (COVID-19). Our study aimed to investigate the relationship between baseline NLR and IMV in ARDS.

Methods

A retrospective study was performed on patients who were diagnosed with ARDS using the Berlin definition and admitted to the First Affiliated Hospital of Soochow University from 2017 to 2022. Clinical data within 24 h after the ARDS diagnosis were collected from the medical record system. Based on the ventilation strategies during hospitalization, patients were divided into three groups and their clinical characteristics were compared. Furthermore, logistic regression analysis was used to screen the independent risk factors for IMV. STROBE checklist was used for this manuscript.

Results

520 ARDS patients were included and the median NLR value in IMV group was significantly higher than that of other groups (P < 0.001). NLR was significantly associated with the requirement of IMV in ARDS patients (OR, 1.042; 95% CI, 1.025–1.060; P < 0.001), other independent risk factors included PaO₂/FiO₂, Hb, lactate, and use of vasoactive drugs (all P < 0.05). Moreover, we found that the duration of IMV was longer in patients with high NLR (8[IQR, 3–13], 10[IQR, 6–16], respectively, P=0.025).

Conclusions

Our results revealed that high baseline NLR level was significantly correlated with an increased risk of IMV in patients with ARDS. Furthermore, higher NLR was associated with prolonged duration of IMV in patients with ARDS.

The Impact of Neutrophil-Lymphocyte Count Ratio in COVID-19: A Systematic Review and Meta-Analysis

Background: The neutrophil-lymphocyte count ratio (NLR) has emerged as a potential prognostic tool for different diseases. In the current coronavirus disease (COVID-19) pandemic, the NLR may be a useful tool for risk scarification and the optimal utilization of limited healthcare resources. However, there is no consensus regarding the optimal value of NLR, and the association with disease severity and mortality. Thus, this study aims to systematically analyze the current evidence of the utility of baseline NLR as a predictive tool for mortality, disease severity in COVID-19 patients. Methods: A compendious screening of electronic databases up to June 15, 2021, was done after enlisting the protocol in PROSPERO (CRD42020202659). Studies evaluating the utility of baseline NLR in COVID-19 are included for this review as per the PRISMA statement. Results: We retrieved a total of 13112 and 12986 COVID-19 patients for survivability and severity over 90 studies. The expired and critically sick patients had elevated baseline NLR on admission, in comparison to survivors and noncritical patients. (SMD = 3.82; 95% CI: 2.79-4.85; I2 = 100% and SMD = 1.42; 95% CI: 1.22-1.63; I2 = 95%, respectively). The summary receiver operating curve analysis for mortality (AUC = 0.87; 95% CI: 0.86-0.87; I2 = 94.7%), and severity (AUC = 0.82; 95% CI: 0.80-0.84; I2 = 79.7%) were also suggestive of its significant predictive value. Conclusions: The elevated NLR on admission in COVID-19 patients is associated with poor outcomes.

Time-Dependent Changes of Laboratory Parameters as Independent Predictors of All-Cause Mortality in COVID-19 Patients

Independent predictors of mortality for COVID-19 patients have been identified upon hospital admission; however, how they behave after hospitalization remains unknown. The aim of this study is to identify clinical and laboratory parameters from admission to discharge or death that distinguish survivors and non-survivors of COVID-19, including those with independent ability to predict mortality. In a cohort of 266 adult patients, clinical and laboratory data were analyzed from admission and throughout hospital stay until discharge or death. Upon admission, non-survivors had significantly increased C reactive protein (CRP), neutrophil count, neutrophil to lymphocyte ratio (NLR) (p < 0.0001, each), ferritin (p < 0.001), and AST (aspartate transaminase) (p = 0.009) compared to survivors. During the hospital stay, deceased patients maintained elevated CRP (21.7 mg/dL [admission] vs. 19.3 [hospitalization], p = 0.060), ferritin, neutrophil count and NLR. Conversely, survivors showed significant reductions in CRP (15.8 mg/dL [admission] vs. 9.3 [hospitalization], p < 0.0001], ferritin, neutrophil count and NLR during hospital stay. Upon admission, elevated CRP, ferritin, and diabetes were independent predictors of mortality, as were persistently high CRP, neutrophilia, and the requirement of invasive mechanical ventilation during hospital stay. Inflammatory and clinical parameters distinguishing survivors from non-survivors upon admission changed significantly during hospital stay. These markers warrant close evaluation to monitor and predict patients’ outcome once hospitalized.

A targetable ‘rogue’ neutrophil-subset, [CD11b+DEspR+] immunotype, is associated with severity and mortality in acute respiratory distress syndrome (ARDS) and COVID-19-ARDS

Neutrophil-mediated secondary tissue injury underlies acute respiratory distress syndrome (ARDS) and progression to multi-organ-failure (MOF) and death, processes linked to COVID-19-ARDS. This secondary tissue injury arises from dysregulated neutrophils and neutrophil extracellular traps (NETs) intended to kill pathogens, but instead cause cell-injury. Insufficiency of pleiotropic therapeutic approaches delineate the need for inhibitors of dysregulated neutrophil-subset(s) that induce subset-specific apoptosis critical for neutrophil function-shutdown. We hypothesized that neutrophils expressing the pro-survival dual endothelin-1/VEGF-signal peptide receptor, DEspR, are apoptosis-resistant like DEspR+ cancer-cells, hence comprise a consequential pathogenic neutrophil-subset in ARDS and COVID-19-ARDS. Here, we report the significant association of increased peripheral DEspR+CD11b+ neutrophil-counts with severity and mortality in ARDS and COVID-19-ARDS, and intravascular NET-formation, in contrast to DEspR[-] neutrophils. We detect DEspR+ neutrophils and monocytes in lung tissue patients in ARDS and COVID-19-ARDS, and increased neutrophil RNA-levels of DEspR ligands and modulators in COVID-19-ARDS scRNA-seq data-files. Unlike DEspR[-] neutrophils, DEspR+CD11b+ neutrophils exhibit delayed apoptosis, which is blocked by humanized anti-DEspR-IgG4^S228P antibody, hu6g8, in ex vivo assays. Ex vivo live-cell imaging of Rhesus-derived DEspR+CD11b+ neutrophils showed hu6g8 target-engagement, internalization, and induction of apoptosis. Altogether, data identify DEspR+CD11b+ neutrophils as a targetable ‘rogue’ neutrophil-subset associated with severity and mortality in ARDS and COVID-19-ARDS.

Prognostic Role of the Neutrophil-to-Lymphocyte Ratio in Intracerebral Hemorrhage: A Systematic Review and Meta-Analysis

The neutrophil-to-lymphocyte ratio (NLR) plays an important role in the progression of intracerebral hemorrhage (ICH). An increasing number of studies have reported that a high NLR is correlated with poor clinical outcomes among patients with ICH. Here, we conducted a systematic review and meta-analysis to evaluate the prognostic value of NLR in the setting of ICH. We performed a comprehensive search of electronic literature databases to identify all relevant studies evaluating the prognostic role of NLR in patients with ICH. Two researchers independently screened the studies and extracted relevant data. We extracted, pooled, and weighted odds ratio (OR) and 95% confidence interval (CI) values using a generic inverse-variance method, and then evaluated the heterogeneity among studies using Q test and I² statistic. Finally, we selected a total of 26 studies including 7,317 patients for the current study. Overall, our results indicated that a high NLR was significantly associated with a poor outcome (OR, 1.32; 95% CI, 1.19–1.46; P < 0.00001), mortality (OR, 1.05; 95% CI, 1.01–1.09; P = 0.02), and neurological deterioration (OR, 1.65; 95% CI, 1.08–2.52; P = 0.02). We did not observe a significant association between NLR and hematoma expansion (OR, 1.04; 95% CI, 0.99–1.08; P = 0.09). Our study indicated that a high NLR is significantly associated with poor clinical outcomes in patients with ICH. As NLR is a simple and easily available biomarker, future studies should focus on exploring its application in the prognostic evaluation of patients with ICH.

Novel predictor of the occurrence of DKA in T1DM patients without infection: A combination of neutrophil/lymphocyte ratio and white blood cells

The role of inflammation has been identified in the pathogenesis of diabetic ketoacidosis (DKA). The neutrophil/lymphocyte ratio (NLR) and white blood cells (WBC) can be used to predict a systemic inflammatory response. Changes in NLR and WBC levels have never been explored in type 1 diabetes mellitus (T1DM) patients with DKA and an uninfected state. This retrospective study included a total of 644 participants. NLR and WBC were measured in the control group (n = 316) and in T1DM patients with mild-DKA (n = 92), severe-DKA (n = 52), and non-DKA (n = 184) in an uninfected state. Then, we assessed the independent predictors of DKA occurrence in T1DM patients in an uninfected state. The diagnostic performance of variables was determined by receiver operating characteristic curve analysis. Serum NLR of T1DM patients is significantly higher than that of normal controls, and if DKA occurs, NLR increases further and increases with the severity of DKA. In addition to diastolic blood pressure, blood urea nitrogen, glycated hemoglobin (HbA1c), and WBC, NLR was also independently associated with DKA in T1DM patients with an uninfected state (OR = 1.386, 95% CI: 1.127-1.705, p = 0.002). Furthermore, the diagnosis analysis showed that except for NLR and WBC, the area under the curve (AUC) of indicators with a statistical difference in patients with and without DKA were 0.747 for DKA diagnosis, and after the addition of NLR and WBC, the AUC was 0.806. The increased NLR level represents a low-cost and highly accessible predictor for DKA in T1DM patients with an uninfected state. The addition of inflammation indicators can play a statistically significant role in the prediction model of the DKA occurrence.

Delayed viral clearance despite high number of activated T cells during the acute phase in Argentinean patients with hantavirus pulmonary syndrome

Background

The hallmarks of HPS are increase of vascular permeability and endothelial dysfunction. Although an exacerbated immune response is thought to be implicated in pathogenesis, clear evidence is still elusive. As orthohantaviruses are not cytopathic CD8⁺ T cells are believed to be the central players involved in pathogenesis.

Methods

Serum and blood samples from Argentinean HPS patients were collected from 2014 to 2019. Routine white blood cell analyses, quantification and characterization of T-cell phenotypic profile, viral load, neutralizing antibody response and quantification of inflammatory mediators were performed.

Findings

High numbers of activated CD4⁺ and CD8⁺ T cells were found in all HPS cases independently of disease severity. We found increased levels of some proinflammatory mediators during the acute phase of illness. Nonetheless, viral RNA remained high, showing a delay in clearance from blood up to late convalescence, when titers of neutralizing antibodies reached a high level.

Interpretation

The high activated phenotypic profile of T cells seems to be unable to resolve infection during the acute and early convalescent phases, and it was not associated with the severity of the disease. Thus, at least part of the activated T cells could be induced by the dysregulated inflammatory response in an unspecific manner. Viral clearance seems to have been more related to high titers of neutralizing antibodies than to the T-cell response.

Funding

This work was supported mainly by the Administración Nacional de Laboratorios e Institutos de Salud (ANLIS) “Dr. Carlos Malbrán”. Further details of fundings sources is included in the appendix.

The red blood cell distribution width-albumin ratio: A promising predictor of mortality in heart failure patients - A cohort study

BACKGROUND

Epidemiological studies suggest that increases in red blood cell distribution width (RDW) and decreases in albumin level can independently predict adverse cardiovascular outcomes. The prognostic value of RDW-albumin ratio (RAR), an innovate biomarker of inflammation, in heart failure (HF) patients has not been assessed. This study aimed to explore the association between RAR and mortality of HF patients.

METHODS

Data on patients diagnosed with HF were extracted from MIMIC-III database version 1.4. Cox proportional hazards models were used to investigate the associations between RAR and mortality of HF patients. HF patients admitted to the Second Affiliated Hospital of Wenzhou Medical University were also enrolled to explore the relationship between RAR and existing indicators of HF.

RESULTS

For 90-day mortality, the HR (95% CI) for the second (4.33＜RAR＜5.44) and the third (RAR＞5.44) tertiles were 2.00 (1.58, 2.54) and 3.63 (2.91, 4.53), respectively, compared to the first tertile (RAR＜4.33). When adjusted for age, gender and ethnicity in Model 1, the adjusted HR (95% CI) value of third tertiles was 3.66 (2.93, 4.56). Further adjust the vital signs, blood biochemical indicators, SOFA score and other parameters in Model II, the adjusted HR value of third tertiles was still statistically significant (HR: 2.70, 95% CI: 2.07-3.51, P < 0.0001). A similar trend was observed for 30-day, one-year mortality. For HF patients, high RAR significantly increased the risk of sepsis and requirement for renal replacement therapy. Additionally, there is a positive correlation between RAR, CRP levels, and NT-proBNP respectively.

CONCLUSION

High level of RAR is associated with increased short- and long-term mortality of patients with heart failure. The RAR is a promising biomarker that is easy to obtain and readily predicts mortality in heart failure patients.

Correlation of neutrophil-to-lymphocyte ratio and clinical outcome of acute thrombotic stroke in patients with COVID-19

The coronavirus disease 2019 (COVID-19) pandemic has caused millions of deaths worldwide. Acute ischemic stroke is a life-threatening risk factor for COVID-19 infection. Neutrophil-to-lymphocyte ratio (NLR) is one of the predictors of poor prognosis in acute ischemic stroke. The aim of this study was to assess the correlation between NLR values and the clinical outcome of acute thrombotic stroke patients with COVID-19 that was measured using the National Institutes of Health Stroke Scale (NIHSS). A cross- sectional hospital-based study was conducted in Dr. Soetomo General Hospital Surabaya, Indonesia. Patients with acute thrombotic stroke and COVID-19 admitted between 1 March 2020 and 31 May 2021 were recruited. The NLR values and the NIHSS scores were assessed during the admission and the correlation between NLR and NIHSS scores was calculated. This study included 21 patients with acute thrombotic stroke and COVID-19, consisting of 12 males and 9 females. The mean age was 57.6 years old. The mean NLR values was 8.33±6.7 and the NIHSS scores ranging from 1 to 33. Our data suggested a positive correlation between NLR values and NIHSS scores, r=0.45 with p=0.041. In conclusion, the NLR value is potentially to be used as a predictor of the clinical outcome in acute thrombotic stroke patients with COVID-19. However, further study is warranted to validate this finding.

Neutrophil-to-lymphocyte ratio is a powerful predictor of adult patients with acute respiratory distress syndrome who might benefit from corticosteroid therapy

BACKGROUND

There is no convincing pharmacological treatment for patients withacute respiratory distress syndrome (ARDS). The efficacy of corticosteroids in ARDS patients remains controversial. Neutrophil-to-Lymphocyte Ratio (NLR) has displayed as a good biomarker for inflammation and immune status, and thus a prognostic marker in some critical patients of ARDS. In this study, we hypothesized that NLR could also serve as an indicator for the efficacy of corticosteroid therapy in ARDS patients.

METHODS

Subjects included in this retrospective cohort study with ARDS patients who were admitted to an academic hospital in Wuhan, China, from May 1st, 2020 to April 20th, 2021. Multivariable logisitic regression model was used to evaluate risk factors of 30-day in-hospital mortality and ventilator-free days. Multi-Cox regression model was used to assess the efficacy of corticosteroid treatment in terms of NLR cutoff value.

RESULTS

Among the 357 patients in our study, 89 (24.9%) had NLR≥14.35 and 268 (75.1%) had NLR<14.35. Among them, 53 patients with NLR≥14.35 (58.9%) received corticosteroids and 99 patients with NLR<14.35 (37.1%) received corticosteroids. Post-adjustment analysis (by APACHE II score and age) revealed that corticosteroid treatment was associated with a decreased risk of 30-day mortality in the NLR≥14.35 group but with an increased risk of death in the NLR<14.35 group. Use of corticosteroid in NLR≥14.35 group significantly increased ventilator-free days (7.0 vs. 13.0, P<0.001).

CONCLUSION

NLR may be used to help identify ARDS patients who may benefit from corticosteroid treatment. Large-sized randomized controlled trials are warranted to determine the optimal cutoff value of NLR.

Increased Neutrophil-Subset Associated With Severity/Mortality In ARDS And COVID19-ARDS Expresses The Dual Endothelin-1/VEGFsignal-Peptide Receptor (DEspR): An Actionable Therapeutic Target

Neutrophil-mediated secondary tissue injury underlies acute respiratory distress syndrome (ARDS) and progression to multi-organ-failure (MOF) and death, processes linked to severe COVID19. This 'innocent bystander' tissue injury arises in dysregulated hyperinflammatory states from neutrophil functions and neutrophil extracellular traps (NETs) intended to kill pathogens, but injure cells instead, causing MOF. Insufficiency of prior therapeutic approaches suggest need to identify dysregulated neutrophil-subset(s) and induce subset-specific apoptosis critical for neutrophil function-shutdown and clearance. We hypothesized that neutrophils expressing the pro-survival dual endothelin-1/signal peptide receptor, DEspR, are apoptosis-resistant just like DEspR+ cancer cells, hence comprise a consequential pathogenic neutrophil-subset in ARDS and COVID19-ARDS. Here, we report correlation of circulating DEspR+CD11b+ activated neutrophils (DESpR+actNs) and NETosing-neutrophils with severity in ARDS and in COVID19-ARDS, increased DEspR+ neutrophils and monocytes in post-mortem ARDS-patient lung sections, and neutrophil DEspR/ET1 receptor/ligand autocrine loops in severe COVID19. Unlike DEspR[-] neutrophils, ARDS patient DEspR+actNs exhibit apoptosis-resistance, which decreased upon ex vivo treatment with humanized anti-DEspR-IgG4S228P antibody, hu6g8. Ex vivo live-cell imaging of non-human primate DEspR+actNs showed hu6g8 target-engagement, internalization, and induction of apoptosis. Altogether, data differentiate DEspR+actNs as a targetable neutrophil-subset associated with ARDS and COVID19-ARDS severity, and suggest DEspR-inhibition as a potential therapeutic paradigm.

Monocyte-to-lymphocyte ratio is associated with 28-day mortality in patients with acute respiratory distress syndrome: a retrospective study

Background

Systemic inflammation relates to the initiation and progression of acute respiratory distress syndrome (ARDS). Neutrophil-to-lymphocyte ratio (NLR) and red blood cell distribution width (RDW)/albumin ratio have been reported to be predictive prognostic biomarkers in ARDS patients. However, the role of monocyte-to-lymphocyte ratio (MLR) as a prognostic inflammatory biomarker in a variety of diseases is rarely mentioned in ARDS. In this study, we explored the relationship between MLR and disease severity in ARDS patients and compared it with other indicators associated with 28-day mortality in patients with ARDS.

Methods

We retrospectively included 268 patients who fulfilled the Berlin definition of ARDS and were admitted to a single institute from 2016 to 2020. Clinical characteristics and experimental test data were collected from medical records within 24 h after the ARDS diagnosis. MLR, NLR, and RDW/albumin ratio levels were calculated. The primary clinical outcome was 28-day mortality. Logistic regression analysis was used to illustrate the relationship between indicators and 28-day mortality. Receiver operating characteristic (ROC) curve was used to evaluate the area under the curve (AUC), and propensity score matching (PSM) was employed to validate our findings.

Results

The median MLR values were higher for non-survivors than for survivors before and after matching (P<0.001, P=0.001, respectively). MLR values were significantly associated with 28-day mortality (OR 2.956; 95% CI 1.873–4.665; P<0.001). MLR and NLR indicators were combined for predictive efficacy analysis, and its AUC reached 0.750. There was a significant increase in 28-day mortality depending on the increasing MLR level: low MLR group 38 (20.4%), high MLR group 47 (57.3%) (P<0.001).

Conclusions

Higher MLR values were associated with 28-day mortality in patients with ARDS. Further investigation is required to verify this relationship with prospectively collected data.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40560-021-00564-6.

Association between Advanced Lung Inflammation Index and 30-Day Mortality in Patients with Acute Respiratory Distress Syndrome

Background and objectives: The advanced lung inflammation index (ALI) was developed to assess the degree of systemic inflammation and has an association with prognosis in patients with lung malignancy. The prognostic value of ALI has not yet been evaluated in patients with acute respiratory distress syndrome (ARDS). Materials and Methods: Between January 2014 and May 2018, patients with ARDS in the medical intensive care unit (ICU) were reviewed retrospectively. The ALI value was calculated as the (body mass index × serum albumin level)/neutrophil-lymphocyte ratio. The cut-off value for distinguishing low from high ALI was defined according to receiver-operating characteristic curve analysis. Results: A total of 164 patients were analyzed. Their median age was 73 years, and 73% was male. The main cause of ARDS was pneumonia (95.7%, 157/164). ICU and in-hospital mortality rates were 59.8% (98/164) and 64% (105/164), respectively. The 30 day mortality was 60.9% (100/164). The median ALI value in non-survivors was lower than that in survivors at 30 day (3.81 vs. 7.39, p = 0.005). In multivariate analysis, low ALI value (≤5.38) was associated with increased 30 day mortality (odds ratio, 2.944, confidence interval 1.178–7.355, p = 0.021). Conclusions: A low ALI value was associated with increased 30 day mortality in patients with ARDS.

The Controversy About the Effects of Different Doses of Corticosteroid Treatment on Clinical Outcomes for Acute Respiratory Distress Syndrome Patients: An Observational Study

Background: Corticosteroid usage in acute respiratory distress syndrome (ARDS) remains controversial. We aim to explore the correlation between the different doses of corticosteroid administration and the prognosis of ARDS.

Methods: All patients were diagnosed with ARDS on initial hospital admission and received systemic corticosteroid treatment for ARDS. The main outcomes were the effects of corticosteroid treatment on clinical parameters and the mortality of ARDS patients. Secondary outcomes were factors associated with the mortality of ARDS patients.

Results: 105 ARDS patients were included in this study. Corticosteroid treatment markedly decreased serum interleukin-18 (IL-18) level (424.0 ± 32.19 vs. 290.2 ± 17.14; p = 0.0003) and improved arterial partial pressure of oxygen/fraction of inspired oxygen (PaO₂/FiO₂) (174.10 ± 65.28 vs. 255.42 ± 92.49; p < 0.0001). The acute physiology and chronic health evaluation (APACHE II) score (16.15 ± 4.41 vs. 14.88 ± 4.57, p = 0.042) decreased significantly on the seventh day after systemic corticosteroid treatment. Interestingly, the serum IL-18 decreased significantly (304.52 ± 286.00 vs. 85.85 ± 97.22, p < 0.0001), whereas the improvement of PaO₂/FiO₂ (24.78 ± 35.03 vs. 97.17 ± 44.82, p < 0.001) was inconspicuous after systemic corticosteroid treatment for non-survival patients, compared with survival patients. Furthermore, the receiver operating characteristic (ROC) model revealed, when equivalent methylprednisolone usage was 146.5 mg/d, it had the best sensitivity and specificity to predict the death of ARDS. Survival analysis by Kaplan–Meier curves presented the higher 45-day mortality in high-dose corticosteroid treatment group (logrank test p < 0.0001). Multivariate Cox regression analyses demonstrated that serum IL-18 level, APACHE II score, D-dimer, and high-dose corticosteroid treatment were associated with the death of ARDS.

Conclusion: Appropriate dose of corticosteroids may be beneficial for ARDS patients through improving the oxygenation and moderately inhibiting inflammatory response. The benefits and risks should be carefully weighed when using high-dose corticosteroid for ARDS.

Trial registration: This work was registered in ClinicalTrials.gov. Name of the registry: Corticosteroid Treatment for Acute Respiratory Distress Syndrome. Trial registration number: NCT02819453. URL of trial registry record: https://register.clinicaltrials.gov.

A systematic review and meta-analysis of effect of vitamin D levels on the incidence of COVID-19

BACKGROUND

Coronavirus disease 2019 (COVID-19) is a disease primarily affecting the respiratory tract, however due to the nature of the pathogenesis it is able to affect the whole body. So far, no causative treatment has been found and the main strategy when dealing with COVID-19 relies on widespread vaccination programs and symptomatic treatment. Vitamin D due to its ability to modulate the immunological system has been proposed as a factor playing role in the organism response to the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Therefore, we decided to perform this meta-analysis which aimed to establish a connection between vitamin D status and COVID-19 infection.

METHODS

Study was designed as a systematic review and meta-analysis. PubMed, EMBASE, Web of Science, Cochrane Collaboration Databases and Scopus electronic databases were searched for relevant studies from database inception to May 10th, 2021. Mean differences (MDs) with their 95% confidence intervals (CI) were calculated.

RESULTS

Thirteen studies providing data for 14,485 participants met the inclusion criteria. Mean vitamin D levels in SARS-CoV-2 negative patients was 17.7 ± 6.9 ng/mL compared to SARS-CoV-2 positive patients 14.1 ± 8.2 ng/mL (MD = 3.93; 95% CI 2.84-5.02; I2 = 99%; p < 0.001).

CONCLUSIONS

Low serum vitamin D levels are statistically significantly associated with the risk of COVID-19 infection. Supplementation of vitamin D especially in the deficiency risk groups is indicated.

The Effects of Neutrophil-Lymphocyte Ratio, Platelet-Lymphocyte Ratio and Prognostic Markers in Determining the Mortality in Patients Diagnosed With Pneumonia in Intensive Care

Objective

In this study, we aimed to reveal the level of predicting mortality of the Neutrophil/Lymphocyte (NLR) and Platelet/Lymphocyte Ratios (TLR) calculated in patients hospitalized with the diagnosis of pneumonia in the intensive care unit when compared with other prognostic scores.

Method

The hospital records of 112 patients who were admitted to the intensive care unit between January 2015 and January 2018 and met the inclusion criteria were retrospectively reviewed. The patients’ demographic data, the NLR and PLR levels, and the APACHE II (Acute Physiology and Chronic Health Evaluation II) and SOFA (Sequential Organ Failure Assessment) scores were calculated from the patient files.

Results

Of the 112 patients examined, 70 were males. The risk analysis showed that the male gender had 2.7 times higher risk of mortality. The NLR, PLR, APACHE II, and SOFA values were found statistically significant in predicting mortality (p<0.001). An evaluation of the risk ratios demonstrated that each one point increase in the NLR increased the mortality risk by 5%, and each one point increase in the SOFA score increased the mortality risk by 13% (p<0.05). In the ROC (receiver operating characteristic) analysis, the NLR assessment proved to be the most powerful, most specific, and sensitive test. The cut-off values were 11.3 for the NLR, 227 for the PLR, 29.8 for the APACHE II scores, and 5.5 for the SOFA scores

Conclusion

We believe that NLR and PLR are strong and independent predictors of mortality that can be easily and cost-effectively tested.

An analysis of the 28-day mortality risk factors in acute respiratory distress syndrome patients and the establishment of prediction models

OBJECTIVE

To explore the risk factors and prediction models of 28-day mortality in acute respiratory distress syndrome (ARDS) patients.

METHODS

A total of 215 ARDS patients treated in our hospital were enrolled in this prospective observational study, including 70 patients who died within 28 days and were placed in the death group, and the remaining 145 patients who survived and were placed in the survival group. The laboratory examination indexes and critical scoring system scores were compared between the two groups. A Cox regression analysis was used to analyze the factors associated with 28-day mortality, and a receiver operating characteristic (ROC) curve was used to analyze the performance of the prediction models.

RESULTS

The ROC curve analysis showed that the erythrocyte distribution width (RDW), the neutrophil to lymphocyte ratio (NLR), the procalcitonin to albumin ratio (PAR), and the Murray lung injury score (MLIS) were effective at diagnosing the 28-day mortality, each with an area under the curve (AUC) of >0.5 (P<0.001). A multivariate Cox analysis showed that the RDW, NLR, PAR, and MLIS were independent predictors of 28-day mortality. The results of the multi-index joint prediction showed that the AUC of RDW+NLR+PAR+MLIS was 0.945 (95% CI: 0.910-0.979), and the sensitivity was as high as 94.25%.

CONCLUSION

NLR, PAR, RDW, and MLIS are independent predictors of 28-day mortality, and their combined prediction can significantly improve the predictive ability of the 28-day mortality in ARDS patients.

Value of quantitative analysis in lung computed tomography in patients severely ill with COVID-19

Introduction

Quantitative computed tomography (QCT) is used to objectively assess the degree of parenchymal impairment in COVID-19 pneumonia.

Materials and methods

Retrospective study on 61 COVID-19 patients (severe and non-severe; 33 men, age 63+/-15 years) who underwent a CT scan due to tachypnea, dyspnoea or desaturation. QCT was performed using VCAR software. Patients’ clinical data was collected, including laboratory results and oxygenation support. The optimal cut-off point for CT parameters for predicting death and respiratory support was performed by maximizing the Youden Index in a receiver operating characteristic (ROC) curve analysis.

Results

The analysis revealed significantly greater progression of changes: ground-glass opacities (GGO) (31,42% v 13,89%, p<0.001), consolidation (11,85% v 3,32%, p<0.001) in patients with severe disease compared to non-severe disease. Five lobes were involved in all patients with severe disease. In non-severe patients, a positive correlation was found between severity of GGO, consolidation and emphysema and sex, tachypnea, chest x-ray (CXR) score on admission and laboratory parameters: CRP, D-dimer, ALT, lymphocyte count and lymphocyte/neutrophil ratio. In the group of severe patients, a correlation was found between sex, creatinine level and death. ROC analysis on death prediction was used to establish the cut-off point for GGO at 24.3% (AUC 0.8878, 95% CI 0.7889–0.9866; sensitivity 91.7%, specificity 75.5%), 5.6% for consolidation (AUC 0.7466, 95% CI 0.6009–0.8923; sensitivity 83.3%, specificity 59.2%), and 37.8% for total (GGO+consolidation) (AUC 0.8622, 95% CI 0.7525–0.972; sensitivity 75%, specificity 83.7%). The cut-off point for predicting respiratory support was established for GGO at 18.7% (AUC 0.7611, 95% CI 0.6268–0.8954; sensitivity 87.5%, specificity 64.4%), consolidation at 3.88% (AUC 0.7438, 95% CI 0.6146–0.8729; sensitivity 100%, specificity 46.7%), and total at 23.5% (AUC 0.7931, 95% CI 0.673–0.9131; sensitivity 93.8%, specificity 57.8%).

Conclusion

QCT is a good diagnostic tool which facilitates decision-making regarding intensification of oxygen support and transfer to an intensive care unit in patients severely ill with COVID-19 pneumonia. QCT can make an independent and simple screening tool to assess the risk of death, regardless of clinical symptoms. Usefulness of QCT to predict the risk of death is higher than to assess the indications for respiratory support.

The Association Between the Baseline and the Change in Neutrophil-to-Lymphocyte Ratio and Short-Term Mortality in Patients With Acute Respiratory Distress Syndrome

Background: Two previous studies have shown that increased neutrophil to lymphocyte ratio (NLR) is associated with short-term prognosis in patients with acute respiratory distress syndrome (ARDS), but it is usually assessed as a single threshold value at baseline. We investigated the relationship between the baseline and the early change in NLR and 30-day mortality in patients with ARDS to evaluate the prognostic value of NLR baseline and NLR changes during the first 7 days after ICU admission. Methods: This is a retrospective cohort study, with all ARDS patients diagnosed according to the Berlin definition from the Medical Information Mart for Intensive Care III (MIMIC-III) database. We calculated the NLR by dividing the neutrophil count by the lymphocyte count. The multivariable logistic regression analysis was used to investigate the relationship between the baseline NLR and short-term mortality. Then the generalized additive mixed model was used to compare trends in NLR over time among survivors and non-survivors after adjusting for potential confounders. Results: A total of 1164 patients were enrolled in our study. Multivariable logistic regression analysis showed that after adjusting for confounders, elevated baseline NLR was a significant risk factor predicting 30-day mortality (OR 1.02, 95%CI 1.01, 1.03, P = 0.0046) and hospital mortality (OR 1.02, 95%CI 1.01, 1.03, P = 0.0003). The result of the generalized additive mixed model showed that the NLR decreased in the survival group and increased in the non-survival group gradually within 7 days after ICU admission. The difference between the two groups showed a trend of increase gradually and the difference increased by an average of 0.67 daily after adjusting for confounders. Conclusions: We confirmed that there was a positive correlation between baseline NLR and short-term mortality, and we found significant differences in NLR changes over time between the non-survival group and the survival group. The early increase in NLR was associated with short-term mortality in ARDS patients.

AI-based analysis of CT images for rapid triage of COVID-19 patients

The COVID-19 pandemic overwhelms the medical resources in the stressed intensive care unit (ICU) capacity and the shortage of mechanical ventilation (MV). We performed CT-based analysis combined with electronic health records and clinical laboratory results on Cohort 1 (n = 1662 from 17 hospitals) with prognostic estimation for the rapid stratification of PCR confirmed COVID-19 patients. These models, validated on Cohort 2 (n = 700) and Cohort 3 (n = 662) constructed from nine external hospitals, achieved satisfying performance for predicting ICU, MV, and death of COVID-19 patients (AUROC 0.916, 0.919, and 0.853), even on events happened two days later after admission (AUROC 0.919, 0.943, and 0.856). Both clinical and image features showed complementary roles in prediction and provided accurate estimates to the time of progression (p < 0.001). Our findings are valuable for optimizing the use of medical resources in the COVID-19 pandemic. The models are available here: https://github.com/terryli710/COVID_19_Rapid_Triage_Risk_Predictor .

The use of neutrophil-to-lymphocyte ratio (NLR) as a marker for COVID-19 infection in Saudi Arabia: A case-control retrospective multicenter study

Objectives:

To assess the neutrophil-to-lymphocyte ratio (NLR) diagnostic and prognostic value in the context of Coronavirus disease-2019 (COVID-19) infection in Saudi Arabia.

Methods:

A case-control study in which 701 confirmed COVID-19 patients (of which 41 were intensive care unit [ICU]-admitted) and 250 control subjects were enrolled. The study was conducted retrospectively in October on patients admitted to 3 separate hospitals in Saudi Arabia namely: King Abdullah Bin Abdulaziz University Hospital (Riyadh), Ohud Hospital (Madinah), and Nojood Medical Center (Madinah) between May and September 2020. Neutrophil-to-lymphocyte ratio was calculated based on absolute neutrophil and lymphocyte count. Institutional ethical approval was obtained prior to the study.

Results:

Patients (median age 35 years), of which 54.8% were females, were younger than the control cohort (median age 48 years). Patients had significantly higher NLR compared to the control group. Intensive care unit admitted patients had significantly higher platelet, WBC and neutrophil counts. The ICU patients’ NLR was almost twice as of the non-intensive patients. The NLR value of 5.5 was found to be of high specificity (96.4%) and positive predictive value (91.4%) in diagnosing COVID-19. Furthermore, it had a very good sensitivity (86.4%) in predicting severe forms of disease, such as, ICU admission.

Conclusion:

Neutrophil-to-lymphocyte ratio is an important tool in determining the COVID-19 clinical status. This study further confirms the prognostic value of NLR in detecting severe infection, and those patients with high NLR should be closely monitored and managed.

Cytopathology of bronchoalveolar lavages in COVID___19 pneumonia: A pilot study

BACKGROUND

Bronchoalveolar lavage (BAL) in patients with severe coronavirus disease 2019 (COVID‐19) may provide additional and complementary findings for the management of these patients admitted to intensive care units (ICUs). This study addresses the cytological features of the infection and highlights the more influential inflammatory components. The correlation between pathological variables and clinical data is also analyzed.

METHODS

The authors performed a retrospective analysis of the cytopathological features of BAL in 20 COVID‐19 patients and 20 members of a matched cohort from a critical ICU who had acute respiratory distress syndrome caused by other pulmonary conditions.

RESULTS

A comparison of the controls (n = 20) and the COVID‐19 patients (n = 20) revealed that the latter had a higher neutrophil count (median, 63.8% of the cell count) with lower percentages of macrophages and lymphocytes. An increase in the expression of CD68‐positive, monocytic multinucleated giant cells (MGCs) was reported; megakaryocytes were not detected on CD61 staining. Perls staining showed isolated elements. In situ RNA analysis demonstrated scattered chromogenic signals in type II pneumocytes. An ultrastructural analysis confirmed the presence of intracytoplasmic vacuoles containing rounded structures measuring 140 nm in diameter (putative viral particles). In COVID‐19 patients, the clinicopathological correlation revealed a positive correlation between lactate dehydrogenase values and MGCs (r = 0.54).

CONCLUSIONS

The analysis of BAL samples might be implemented as a routine practice for the evaluation of COVID‐19 patients in ICUs in the appropriate clinical scenario. Additional studies using a larger sample size of patients who developed COVID‐19 during the second wave of the epidemic in the autumn of 2020 are needed to further support our findings.

An analysis of the cytological features of bronchoalveolar lavage samples can provide useful information for the management of coronavirus disease 2019 patients in the intensive care unit.

Clinical criteria for COVID-19-associated hyperinflammatory syndrome: a cohort study

BACKGROUND

A subset of patients with COVID-19 develops a hyperinflammatory syndrome that has similarities with other hyperinflammatory disorders. However, clinical criteria specifically to define COVID-19-associated hyperinflammatory syndrome (cHIS) have not been established. We aimed to develop and validate diagnostic criteria for cHIS in a cohort of inpatients with COVID-19.

METHODS

We searched for clinical research articles published between Jan 1, 1990, and Aug 20, 2020, on features and diagnostic criteria for secondary haemophagocytic lymphohistiocytosis, macrophage activation syndrome, macrophage activation-like syndrome of sepsis, cytokine release syndrome, and COVID-19. We compared published clinical data for COVID-19 with clinical features of other hyperinflammatory or cytokine storm syndromes. Based on a framework of conserved clinical characteristics, we developed a six-criterion additive scale for cHIS: fever, macrophage activation (hyperferritinaemia), haematological dysfunction (neutrophil to lymphocyte ratio), hepatic injury (lactate dehydrogenase or asparate aminotransferase), coagulopathy (D-dimer), and cytokinaemia (C-reactive protein, interleukin-6, or triglycerides). We then validated the association of the cHIS scale with in-hospital mortality and need for mechanical ventilation in consecutive patients in the Intermountain Prospective Observational COVID-19 (IPOC) registry who were admitted to hospital with PCR-confirmed COVID-19. We used a multistate model to estimate the temporal implications of cHIS.

FINDINGS

We included 299 patients admitted to hospital with COVID-19 between March 13 and May 5, 2020, in analyses. Unadjusted discrimination of the maximum daily cHIS score was 0·81 (95% CI 0·74-0·88) for in-hospital mortality and 0·92 (0·88-0·96) for mechanical ventilation; these results remained significant in multivariable analysis (odds ratio 1·6 [95% CI 1·2-2·1], p=0·0020, for mortality and 4·3 [3·0-6·0], p<0·0001, for mechanical ventilation). 161 (54%) of 299 patients met two or more cHIS criteria during their hospital admission; these patients had higher risk of mortality than patients with a score of less than 2 (24 [15%] of 138 vs one [1%] of 161) and for mechanical ventilation (73 [45%] vs three [2%]). In the multistate model, using daily cHIS score as a time-dependent variable, the cHIS hazard ratio for worsening from low to moderate oxygen requirement was 1·4 (95% CI 1·2-1·6), from moderate oxygen to high-flow oxygen 2·2 (1·1-4·4), and to mechanical ventilation 4·0 (1·9-8·2).

INTERPRETATION

We proposed and validated criteria for hyperinflammation in COVID-19. This hyperinflammatory state, cHIS, is commonly associated with progression to mechanical ventilation and death. External validation is needed. The cHIS scale might be helpful in defining target populations for trials and immunomodulatory therapies.

FUNDING

Intermountain Research and Medical Foundation.

CT-based Rapid Triage of COVID-19 Patients: Risk Prediction and Progression Estimation of ICU Admission, Mechanical Ventilation, and Death of Hospitalized Patients

The wave of COVID-19 continues to overwhelm the medical resources, especially the stressed intensive care unit (ICU) capacity and the shortage of mechanical ventilation (MV). Here we performed CT-based analysis combined with electronic health records and clinical laboratory results on Cohort 1 (n = 1662 from 17 hospitals) with prognostic estimation for the rapid stratification of PCR confirmed COVID-19 patients. These models, validated on Cohort 2 (n = 700) and Cohort 3 (n = 662) constructed from 9 external hospitals, achieved satisfying performance for predicting ICU, MV and death of COVID-19 patients (AUROC 0.916, 0.919 and 0.853), even on events happened two days later after admission (AUROC 0.919, 0.943 and 0.856). Both clinical and image features showed complementary roles in events prediction and provided accurate estimates to the time of progression (p<.001). Our findings are valuable for delivering timely treatment and optimizing the use of medical resources in the pandemic of COVID-19.

Neutrophil-to-Lymphocyte Ratio and Outcomes in Louisiana COVID-19 Patients

BACKGROUND

Due to the rapidly escalating number of cases and the low baseline of overall health in Louisiana, we sought to determine the prognostic value of the neutrophil-to-lymphocyte ratio (NLR) in hospitalized COVID patients in two major metropolitan areas with the highest prevalence of cases and exceedingly high rates of obesity and other comorbid conditions. We hypothesized that elevated NLR would be a prognostic indicator of mortality.

METHODS

This was a review of a prospective registry of adult (18+ years) hospitalized Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) patients from two large urban safety net hospitals in Louisiana. Blood cell counts at days 2 and 5 were used to obtain NLR. Receiver operating characteristic curve analysis assessed predictive capacity of NLR on mortality. Kaplan-Meier survival analysis and Cox regression models examined the effect of NLR on survival.

RESULTS

The study population of 125 patients was majority African American (88.6%) and female (54.8%) with a mean age and body mass index of 58.7 years and 34.2. Most (96.0%) had comorbidities of which hypertension (72.0%), obesity (66.7%), and diabetes (40.0%) were the most common. Mortality was 18.4%. NLR > 4.94 on day 1 predicted intubation (P = 0.02). NLR above established cutoff values on hospital days 2 and 5 each significantly predicted mortality (P < 0.001 and P = 0.002, respectively).

CONCLUSIONS

NLR is a prognostic factor for endotracheal intubation upon hospital admission and independent predictor for risk of mortality in SARS-CoV-2 patients on subsequent hospital days. Clinical research efforts should examine effects of strategies such as arginase inhibition alone and/or inhaled nitric oxide to ameliorate the effects of elevated NLR.

Prognostic Value of Neutrophil-to-Lymphocyte Ratio in Predicting Death Risk in Patients with Severe Hand, Foot and Mouth Disease

INTRODUCTION

Severe hand, foot, and mouth disease (HFMD) may lead to serious complications, which cause child mortality during outbreaks. The aim of this study was to determine whether neutrophil-to-lymphocyte ratio (NLR) can predict death risk in severe HFMD.

METHODS

Medical records for 664 severe HFMD patients were retrospectively examined, and NLR was calculated from blood counts. Youden's index was calculated to determine the optimal NLR cutoff. Uni- and multivariate logistic regression were used to determine death risk factors associated with severe HFMD.

RESULTS

An NLR cutoff value of 2.01 and 2.50 respectively predicted mortality among all 664 severe HFMD and 137 critical HFMD. Among all 664 patients, the multivariate model identified the following as independently associated with death risk: high fever (OR 3.342, 95% CI 1.736-6.432), EV71 infection (OR 3.200, 95% CI 1.529-6.698), fasting glucose (OR 37.343, 95% CI 18.616-74.909), and NLR (>2.01) (OR 2.142, 95% CI 1.125-4.079). Among 137 critical HFMD, EV71 infection (OR 3.441, 95% CI 1.132-10.462), fasting glucose (OR 14.173, 95% CI 4.920-40.827), and NLR (>2.50) (OR 4.166, 95% CI 1.570-11.051) were associated with death risk.

CONCLUSION

In conclusion, NLR (>2.01) in severe HFMD and NLR (>2.50) in critical HFMD patients may be associated with increased death risk.

Blood urea nitrogen to serum albumin ratio independently predicts 30-day mortality and severity in patients with Escherichia coli bacteraemia

BACKGROUND

Elevated blood urea nitrogen to serum albumin (BUN/ALB) ratio had been identified as an independent risk factor related to mortality in community-acquired and hospital-acquired pneumonia. This study aimed to investigate whether this clinical index can predict the clinical outcomes of E. coli bacteraemia.

MATERIAL AND METHODS

Clinical data were collected from patients with E. coli bacteraemia attended at our hospital between January 2012 and December 2018. The endpoints were mortality within 30 days after the diagnosis of E. coli bacteraemia and intensive care (IC) requirement. Cox regression analysis was performed to evaluate the risk factors.

RESULTS

A total of 398 patients with E. coli bacteraemia were enrolled in this study and 56 patients died within 30 days after bacteraemia onset. Multivariate Cox regression analysis showed that age greater than 65 years, lymphocyte count<.8×10e9/L, elevated BUN/ALB ratio, increased SOFA score, carbapenem resistance, central venous catheterization before onset of bacteraemia, and infection originating from abdominal cavity were independent risk factors for 30-day mortality (P<.05). The risk factors associated with IC requirement were similar to those for 30-day mortality except central venous catheterization before onset of bacteraemia. The area under the receiver-operating characteristic curve for BUN/ALB ratio predicting 30-day mortality and IC requirement was similar to that for SOFA score, but higher than that for lymphocyte count. The cut-off points of BUN/ALB ratio to predict 30-day mortality and IC requirement were both .3.

CONCLUSIONS

BUN/ALB ratio is a simple but independent predictor of 30-day mortality and severity in E. coli bacteraemia. A higher BUN/ALB ratio at the onset of bacteraemia predicts a higher mortality rate and IC requirement.

Inflammation, Thrombosis, and Destruction: The Three-Headed Cerberus of Trauma- and SARS-CoV-2-Induced ARDS

Physical trauma can be considered an unrecognized "pandemic" because it can occur anywhere and affect anyone and represents a global burden. Following severe tissue trauma, patients frequently develop acute lung injury (ALI) and/or acute respiratory distress syndrome (ARDS) despite modern surgical and intensive care concepts. The underlying complex pathophysiology of life-threatening ALI/ARDS has been intensively studied in experimental and clinical settings. However, currently, the coronavirus family has become the focus of ALI/ARDS research because it represents an emerging global public health threat. The clinical presentation of the infection is highly heterogeneous, varying from a lack of symptoms to multiple organ dysfunction and mortality. In a particular subset of patients, the primary infection progresses rapidly to ALI and ARDS. The pathophysiological mechanisms triggering and driving severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-induced ALI/ARDS are still poorly understood. Although it is also generally unknown whether insights from trauma-induced ARDS may be readily translated to SARS-CoV-2-associated ARDS, it was still recommended to treat coronavirus-positive patients with ALI/ARDS with standard protocols for ALI/ARDS. However, this strategy was questioned by clinical scientists, because it was documented that some severely hypoxic SARS-CoV-2-infected patients exhibited a normal respiratory system compliance, a phenomenon rarely observed in ARDS patients with another underlying etiology. Therefore, coronavirus-induced ARDS was defined as a specific ARDS phenotype, which accordingly requires an adjusted therapeutic approach. These suggestions reflect previous attempts of classifying ARDS into different phenotypes that might overall facilitate ARDS diagnosis and treatment. Based on the clinical data from ARDS patients, two major phenotypes have been proposed: hyper- and hypo-inflammatory. Here, we provide a comparative review of the pathophysiological pathway of trauma-/hemorrhagic shock-induced ARDS and coronavirus-induced ARDS, with an emphasis on the crucial key points in the pathogenesis of both these ARDS forms. Therefore, the manifold available data on trauma-/hemorrhagic shock-induced ARDS may help to better understand coronavirus-induced ARDS.

Neutrophil-to-Lymphocyte Ratio and Platelet-to-Lymphocyte Ratio as Inflammatory Markers in Patients With Welders' Lung Disease

OBJECTIVE

To investigate neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) in patients with welders' lung disease (PWLD) and its relation with pulmonary function parameters.

METHODS

One hundred sixteen male PWLD and 118 healthy non-exposed individuals were recruited. Pulmonary function tests (PFTs), complete blood count, erythrocyte sedimentation rate (SED), c-reactive protein (CRP), NLR and PLR of both groups were retrospectively analyzed.

RESULTS

NLR, PLR, WBC, ESR, and CRP were significantly higher in PWLD compared to controls (all P < 0.001). All PFTs, except for FEV1/FVC, significantly decreased in PWLD compared to controls as. NLR correlated positively with ESR (r = 0.241 and P < 0.001).

CONCLUSION

Our results show that NLR and PLR can be considered as new inflammatory markers in PWLD with their cheap, fast and easily measurable feature with routine blood count analysis.

Use of Neutrophil-to-Lymphocyte and Platelet-to-Lymphocyte Ratios in COVID-19

BACKGROUND

As the pandemic of coronavirus disease 2019 (COVID-19) continues, prognostic markers are now being identified. The neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) are easily accessible values that have been known to correlate with inflammation and prognosis in several conditions. We used the available data to identify the association of NLR and PLR with the severity of COVID-19.

METHODS

A literature search using EMBASE, MEDLINE, and Google Scholar for studies reporting the use of NLR and PLR in COVID-19 published until April 28, 2020, was performed. Random effects meta-analysis was done to estimate standard mean difference (SMD) of NLR and PLR values with 95% confidence interval (CI) between severe and non-severe COVID-19 cases.

RESULTS

A total of 20 studies with 3,508 patients were included. Nineteen studies reported NLR values, while five studies reported PLR values between severe and non-severe COVID-19 patients. Higher levels of NLR (SMD: 2.80, 95% CI: 2.12 - 3.48, P < 0.00001) and PLR (SMD: 1.82, 95% CI: 1.03 - 2.61, P < 0.00001)) were seen in patients with severe disease compared to non-severe disease.

CONCLUSIONS

NLR and PLR can be used as independent prognostic markers of disease severity in COVID-19.

Complete Blood Count and Derived Indices: Evolution Pattern and Prognostic Value in Adult Burned Patients

Certain parameters of complete blood count (CBC) such as red cell distribution width (RDW) and mean platelet volume, as well as neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and RDW-to-platelet ratio (RPR) have been associated with inflammatory status and outcome in diverse medical conditions. The aim of this study was to describe the evolution pattern of these parameters in adult burned patients. Adult burned patients admitted to the National Burn Center in Uruguay between May 2017 and February 2018 (discovery cohort) and between March 2018 and August 2019 (validation cohort) were included. Patients' characteristics and outcomes were recorded, as well as CBC parameters on days 1, 3, 5, and 7 after thermal injury. Eighty-eight patients were included in the discovery cohort. Total body surface area burned was 14 [7-23]% and mortality was 15%. Nonsurvivors presented higher RDW and mean platelet volume (P < .01). NLR decreased after admission in all patients (P < .01), but was higher in nonsurvivors (P < .01). Deceased patients also presented higher RPR on days 3, 5, and 7 (P < .001). On the contrary, PLR was reduced in nonsurvivors (P < .05). There was a significant correlation between NLR on admission and burn extension and severity. Kaplan-Meier analysis revealed that NLR, PLR, and RPR could identify patients with increased mortality. These findings were confirmed in the validation cohort (n = 95). Basic CBC parameters and derived indices could be useful as biomarkers to determine prognosis in adults with thermal injuries.

A systematic review of biomarkers multivariately associated with acute respiratory distress syndrome development and mortality

Background

Heterogeneity of acute respiratory distress syndrome (ARDS) could be reduced by identification of biomarker-based phenotypes. The set of ARDS biomarkers to prospectively define these phenotypes remains to be established.

Objective

To provide an overview of the biomarkers that were multivariately associated with ARDS development or mortality.

Data sources

We performed a systematic search in Embase, MEDLINE, Web of Science, Cochrane CENTRAL, and Google Scholar from inception until 6 March 2020.

Study selection

Studies assessing biomarkers for ARDS development in critically ill patients at risk for ARDS and mortality due to ARDS adjusted in multivariate analyses were included.

Data extraction and synthesis

We included 35 studies for ARDS development (10,667 patients at risk for ARDS) and 53 for ARDS mortality (15,344 patients with ARDS). These studies were too heterogeneous to be used in a meta-analysis, as time until outcome and the variables used in the multivariate analyses varied widely between studies. After qualitative inspection, high plasma levels of angiopoeitin-2 and receptor for advanced glycation end products (RAGE) were associated with an increased risk of ARDS development. None of the biomarkers (plasma angiopoeitin-2, C-reactive protein, interleukin-8, RAGE, surfactant protein D, and Von Willebrand factor) was clearly associated with mortality.

Conclusions

Biomarker data reporting and variables used in multivariate analyses differed greatly between studies. Angiopoeitin-2 and RAGE in plasma were positively associated with increased risk of ARDS development. None of the biomarkers independently predicted mortality. Therefore, we suggested to structurally investigate a combination of biomarkers and clinical parameters in order to find more homogeneous ARDS phenotypes.

PROSPERO identifier

PROSPERO, CRD42017078957