Single emergency room measurement of neutrophil/lymphocyte ratio for early detection of acute kidney injury (AKI)

Early Identification of Sepsis-Induced Acute Kidney Injury by Using Monocyte Distribution Width, Red-Blood-Cell Distribution, and Neutrophil-to-Lymphocyte Ratio

Sepsis-induced acute kidney injury (AKI) is a common complication in patients with severe illness and leads to increased risks of mortality and chronic kidney disease. We investigated the association between monocyte distribution width (MDW), red-blood-cell volume distribution width (RDW), neutrophil-to-lymphocyte ratio (NLR), sepsis-related organ-failure assessment (SOFA) score, mean arterial pressure (MAP), and other risk factors and sepsis-induced AKI in patients presenting to the emergency department (ED). This retrospective study, spanning 1 January 2020, to 30 November 2020, was conducted at a university-affiliated teaching hospital. Patients meeting the Sepsis-2 consensus criteria upon presentation to our ED were categorized into sepsis-induced AKI and non-AKI groups. Clinical parameters (i.e., initial SOFA score and MAP) and laboratory markers (i.e., MDW, RDW, and NLR) were measured upon ED admission. A logistic regression model was developed, with sepsis-induced AKI as the dependent variable and laboratory parameters as independent variables. Three multivariable logistic regression models were constructed. In Model 1, MDW, initial SOFA score, and MAP exhibited significant associations with sepsis-induced AKI (area under the curve [AUC]: 0.728, 95% confidence interval [CI]: 0.668-0.789). In Model 2, RDW, initial SOFA score, and MAP were significantly correlated with sepsis-induced AKI (AUC: 0.712, 95% CI: 0.651-0.774). In Model 3, NLR, initial SOFA score, and MAP were significantly correlated with sepsis-induced AKI (AUC: 0.719, 95% CI: 0.658-0.780). Our novel models, integrating MDW, RDW, and NLR with initial SOFA score and MAP, can assist with the identification of sepsis-induced AKI among patients with sepsis presenting to the ED.

The predictive value of hematological inflammatory markers for acute kidney injury and mortality in adults with hemophagocytic Lymphohistiocytosis: A retrospective analysis of 585 patients

BACKGROUND

Hemophagocytic lymphohistiocytosis (HLH) is a rare immunological hyperactivation-related disease with a high mortality rate. The purpose of this study was to examine the relationship between complete blood count parameters and the occurrence of acute kidney injury (AKI) and mortality in patients with HLH.

METHODS

We included 585 adult patients with HLH. Logistic regression models for AKI and 28-day mortality were developed.

RESULTS

Multivariate logistic regression models revealed that hemoglobin (HB) ≤ 7.3 g/dl (adjusted OR, 1.651; 95% CI, 1.044-2.612), hemoglobin-to-red blood cell distribution width ratio (HRR) < 0.49 (adjusted OR, 1.692), neutrophil-to-lymphocyte ratio (NLR) ≥ 3.15 (adjusted OR, 1.697), and neutrophil-to-lymphocyte-platelet ratio (NLPR) ≥ 11.0 (adjusted OR, 1.608) were independent risk factors for the development of AKI. Moreover, lower platelet levels (31 × 109/L < platelets < 84 × 109/L, adjusted OR, 2.133; platelets ≤ 31 × 109/L, adjusted OR, 3.545) and higher red blood cell distribution width-to-platelet ratio (RPR) levels (0.20 < RPR < 0.54, adjusted OR, 2.595; RPR ≥ 0.54, adjusted OR, 4.307), lymphocytes ≤ 0.34 × 109/L (adjusted OR, 1.793), NLPR ≥ 11.0 (adjusted OR, 2.898), and the aggregate index of systemic inflammation (AISI) ≤ 7 (adjusted OR,1.778) were also independent risk factors for 28-day mortality. Furthermore, patients with AKI had a worse prognosis than those without AKI (P < 0.05).

CONCLUSION

In patients with HLH, hematological parameters are of great value for the early identification of patients at high risk of AKI and 28-day mortality.

Dynamic nature and prognostic value of the neutrophil-to-lymphocyte ratio in critically ill patients with acute kidney injury on continuous renal replacement therapy: A multicenter cohort study

Introduction

Patients with acute kidney injury (AKI) receiving renal replacement therapy constitute the subgroup of AKI with the highest risk of mortality. Despite recent promising findings on the neutrophil-to-lymphocyte ratio (NLR) in AKI, studies have not yet addressed the clinical implication of the NLR in this population. Therefore, we aimed to examine the prognostic value of NLR in critically ill patients requiring continuous renal replacement therapy (CRRT), especially focusing on temporal changes in NLR.

Methods

We enrolled 1,494 patients with AKI who received CRRT in five university hospitals in Korea between 2006 and 2021. NLR fold changes were calculated as the NLR on each day divided by the NLR value on the first day. We performed a multivariable Cox proportional hazard analysis to assess the association between the NLR fold change and 30-day mortality.

Results

The NLR on day 1 did not differ between survivors and non-survivors; however, the NLR fold change on day 5 was significantly different. The highest quartile of NLR fold change during the first 5 days after CRRT initiation showed a significantly increased risk of death (hazard ratio [HR], 1.65; 95% confidence intervals (CI), 1.27–2.15) compared to the lowest quartile. NLR fold change as a continuous variable was an independent predictor of 30-day mortality (HR, 1.14; 95% CI, 1.05–1.23).

Conclusion

In this study, we demonstrated an independent association between changes in NLR and mortality during the initial phase of CRRT in AKI patients receiving CRRT. Our findings provide evidence for the predictive role of changes in the NLR in this high-risk subgroup of AKI.

Neutrophil-to-Lymphocyte ratio as a prognostic marker of mortality and disease severity in septic Acute kidney injury Patients: A retrospective study

BACKGROUND

Acute kidney injury (AKI) is a frequent complication of sepsis associated with increased mortality and morbidity. The neutrophil-to-lymphocyte ratio (NLR) has been shown as a risk factor for septic AKI. In this study, we aimed to further evaluate NLR's prediction value on the prognosis of septic AKI patients.

METHODS

Septic AKI patients at a tertiary university-affiliated medical center were retrospectively enrolled from August 2015 to August 2021. The primary outcomes were 30-day and 90-day mortality, and secondary outcomes were disease severity, length of stay, and rehospitalization in survivors. Kaplan-Meier curves, Cox proportional hazards, cubic spline and logistics regression analyses were performed for adverse outcomes basing on NLR. The predictive value of NLR on morality was also estimated by the area under the receiver operating characteristic curve (AUROC).

RESULTS

A total of 309 septic AKI patients were included with a mean age of 57.8 ± 18.1 years and 92 (29.8 %) being female. The 30-day mortality was 43.4 % and 90-day morality was 61.8 %. When divided by the median of NLR at hospital admission, patients in the high NLR group were associated with an increased 30-day/90-day mortality. After adjusting for multiple covariates, the predictive value of NLR remained significant for 30-day mortality (HR: 2.96, 95 % CI: 1.48-5.92, p = 0.002) and 90-day mortality (HR: 1.88, 95 % CI: 1.11-3.16, p = 0.018). NLR at admission had the highest AUROC (0.618) for 30-day mortality compared with other parameters such as white blood cell (0.573), neutrophil (0.579), lymphocyte (0.567), platelet (0.546), BUN (0.580), albumin (0.545), C-reactive protein (0.571) and procalcitonin (0.534). A similar predictive value on mortality was also observed for NLR measured at septic AKI diagnosis. For secondary outcomes, high NLR was associated with increased risk of transfer to ICU, mechanical ventilation, stage-3 AKI and renal replacement therapy, but not with length of hospital/ICU stay or long-term rehospitalization.

CONCLUSION

High NLR is independently associated with 30-day/90-day mortality and disease severity in septic AKI patients. NLR may serve as an economic and widely available biomarker of septic AKI prognosis.

Factors associated with acute kidney injury in patients undergoing extracorporeal membrane oxygenation: retrospective cohort

OBJECTIVE

To identify factors associated with acute kidney injury in patients undergoing extracorporeal membrane oxygenation.

METHOD

Retrospective cohort study conducted in an adult Intensive Care Unit with patients undergoing extracorporeal membrane oxygenation from 2012 to 2021. The research used the Kidney Disease Improving Global Outcomes as criteria for definition and classification of acute kidney injury. A multiple logistic regression model was developed to analyze the associated factors.

RESULTS

The sample was composed of 122 individuals, of these, 98 developed acute kidney injury (80.3%). In multiple regression, the associated factors found were vasopressin use, Nursing Activities Score, and glomerular filtration rate.

CONCLUSION

The use of vasopressin, the Nursing Activities Score, and the glomerular filtration rate were considered as factors related to the development of acute kidney injury in patients undergoing extracorporeal membrane oxygenation.

Immature granulocytes as biomarkers of inflammation in children with predialysis chronic kidney disease

BACKGROUND

Chronic inflammation in patients with predialysis chronic kidney disease (CKD) is quite common. We aimed to investigate the relationship of the percentage of immature granulocytes (IG%) and immature granulocyte count (IGC) with inflammation in children with predialysis CKD.

METHODS

The data from children with stage 2-4 CKD and a control group of healthy children were evaluated retrospectively. A highly-sensitive C-reactive protein (hs-CRP) level above 5 mg/dL was considered the presence of inflammation. The IGCs were calculated in the white cell differential channel of the Sysmex XN-9000 using the fluorescent flow cytometry method. The IG% was expressed as percentage of total leucocyte concentration.

RESULTS

The data from 57 patients (30 stage 2 CKD, 15 stage 3 CKD, 12 stage 4 CKD) and 46 controls were analyzed. hs-CRP levels, IG%, IGC, white blood cell (WBC) and neutrophil counts, and neutrophil-to-lymphocyte ratio (NLR) were higher in patients than the control group (p < 0.000, p < 0.000, p < 0.000, p = 0.001, p = 0.002, p < 0.000, respectively). Both IG% and IGC were positively correlated with hs-CRP, WBC and neutrophil counts, and NLR (r = 0.485, p < 0.000; r = 0.379, p = 0.004; r = 0.543, p < 0.000; r = 0.628, p < 0.000 for IG%; r = 0.379, p = 0.004; r = 0.351, p = 0.007; r = 0.525, p < 0.000; r = 0.601, p < 0.000 for IGC, respectively). A ROC analysis of the relationship between IGC, IG%, and inflammation showed IGC and IG% had predictive value for the presence of inflammation (cut-off value: 0.035 × 10⁶/mL, AUC: 0.799 ± 0.061, sensitivity: 74.2%, specifity: 63%, p < 0.001 for IGC; cut-off value: 0.45%, AUC: 0.838 ± 0.056, sensitivity: 70.8%, specifity: 67.3%, p = 0.001 for IG%).

CONCLUSIONS

Immature granulocytes may be used as a biomarker of inflammation in children with predialysis CKD. A higher resolution version of the Graphical abstract is available as Supplementary information.

Neutrophil-to-lymphocyte ratio-a new diagnostic and prognostic marker of acute kidney injury. Barriers to broad clinical application

Hospital-acquired acute kidney injury is a heterogeneous clinical syndrome that has multiple aetiologies, widely differing pathogeneses, variable clinical manifestations, and diverse outcomes. There is a persistent unmet need for novel biomarkers that offer timely diagnosis and accurate prediction of the short- and long-term sequelae of acute kidney injury (AKI). AKI is associated with systemic and intrarenal inflammation. The neutrophil-to-lymphocyte ratio (NLR), a readily available marker of inflammation and physiologic stress, has gained increasing attention as universal marker in AKI patients. Numerous retrospective cross-sectional studies assessed the clinical usefulness of this test in high-risk patients with a known time point of the renal injury (surgery, radiological procedures). Strong associations have been demonstrated between high NLR and early onset, progression or recovery of AKI, and the in-hospital and post-discharge mortality of these patients. However, the results were contradictory. The huge heterogeneity of reporting concerning the timing and numbers of blood samples, calculation of the optimal cut-off and the demographic and clinical features of the patient cohorts were confounders. Uncertainty in the optimal cut-off values defining high NLR, the lack of prospective validation of this test and limited understanding of the strengths of associations between NLR and clinical outcomes were further barriers for the clinical adoption of NLR as a valid diagnostic and prognostic test in AKI patients.

The Predictive Role of Systemic Inflammatory Markers in the Development of Acute Kidney Failure and Mortality in Patients with Abdominal Trauma

Background: Abdominal trauma is defined as a variety of injuries to the abdominal wall, solid or hollow intra-abdominal organs, and various intra-abdominal vessels. Recently, there has been a significant amount of interest in the establishment of a reliable biomarker that can predict the outcome in patients with an abdominal injury. The purpose of this study is to confirm the predictive role of inflammatory biomarkers and underlying risk factors and the risk of acute kidney insufficiency (AKI) developing and mortality in abdominal trauma patients; Materials and methods: The current study was intended as an observational, analytical, retrospective cohort study and included all patients over 18 years of age with a diagnosis of abdominal trauma confirmed through a CT scan admitted to the County Emergency Clinical Hospital of Targu-Mureș, Romania between January 2017, and December 2021; Results: Non-survivor patients had a greater age (p = 0.02), as well as a higher prevalence of ischemic heart disease (IHD) (p = 0.007), history of myocardial infarction (MI) (p = 0.002), peripheral arterial disease (PAD) (p = 0.01), chronic kidney disease (CKD) (p = 0.01), and all risk factors (p = 0.0004 and p < 0.0001). In terms of injured organs, we have in the second group a higher incidence of kidney injury (p = 0.003) and hemoperitoneum (p = 0.008). Multivariate analysis showed a high baseline value for all inflammatory biomarkers that are independent predictors of adverse outcomes for all recruited patients. Furthermore, for all hospitalized patients, the history of MI (p = 0.03; p = 0.001; and p = 0.003), PAD (p = 0.01; p = 0.01; and p = 0.002), obesity (for all p < 0.0001), CKD (p < 0.001; p = 0.01; and p = 0.001), and kidney injury (p = 0.02; p = 0.004; and p = 0.01) were independent predictors of all outcomes. Moreover, IHD (p = 0.008 and p = 0.02), tobacco (p < 0.0001 and p = 0.02), and hemoperitoneum (p = 0.009 and p = 0.01) were predictors of mortality and composite endpoint, but not for AKI risk, as well as atrial fibrillation [AF] (p = 0.04) as predictors of the composite endpoint Conclusions: Higher monocyte to lymphocyte ratio (MLR), platelets to lymphocyte ratio (PLR), systemic inflammatory index (SII), neutrophil to lymphocyte ratios (NLR), aggregate inflammatory systemic index (AISI), and systemic inflammatory response index (SIRI) levels at admission, according to our data, highly predict AKI risk and death.

Preoperative Neutrophil-Lymphocyte Ratio for predicting surgery-related acute kidney injury in non-cardiac surgery patients under general anaesthesia: A retrospective cohort study

Background

This study was conducted to investigate the relationship between the Neutrophil-Lymphocyte Ratio (NLR) and the incidence of surgery-related acute kidney injury (AKI) in non-cardiac surgery patients under general anaesthesia.

Methods

In this retrospective study, 5057 patients from Third Xiangya hospital from January 2012 to December 2016 and 1686 patients from Second Xiangya hospital from January 2016 to December 2016 for non-cardiac surgery under general anesthesia were included. According to receiver operating characteristic (ROC) curve constructed by NLR for postoperative AKI, the cut-off point was obtained as the basis for grouping low or high NLR. The baseline characteristics of two sets were compared with each other. A multi-factor model was constructed by Least absolute shrinkage and selection operator (LASSO) method with the training set, and verified by outside validation set.

Results

243 patients (3.604%) developed postoperative AKI. The ROC curve showed that the AUC of the NLR for predicting postoperative AKI in non-cardiac surgery was 0.743 (95% CI, 0.717–0.769), and the cut-off value was 3.555 (sensitivity, 86.4%; specificity 51.9%). There was no significant difference in the baseline characteristics of training set and validation set. The AUC in the training set was 0.817 (95% CI, 0.784–0.850), and the AUC in the validation set was 0.804 (95% CI, 0.749–0.858), the AUC deviation was 0.012 (P > 0.05) from validation set, and the likelihood ratio test showed P < 0.05.

Conclusion

This study showed that preoperative high NLR (NLR≥3.555) was an independent risk factor associated with postoperative AKI (OR, 2.410; 95% CI, 1.371–4.335) in patients for non-cardiac surgery under general anesthesia.

Prediction Models for One-Year Survival of Adult Patients with Acute Kidney Injury: A Longitudinal Study Based on the Data from the Medical Information Mart for Intensive Care III Database

Acute kidney injury (AKI) is a common complication of acute illnesses with unfavorable outcomes. This cohort study aimed at constructing prediction models for one-year survival in adult AKI patients based on prognostic nutritional index (PNI), platelet-to-lymphocyte ratio (PLR), neutrophil percentage-to-albumin ratio (NPAR), or neutrophil-to-lymphocyte ratio (NLR), respectively. In total, 6050 patients from Medical Information Mart for Intensive Care III (MIMIC-III) were involved. The least absolute shrinkage and selection operator (LASSO) regression was utilized to screen possible covariates. The samples were randomly divided into the training set and the testing set at a ratio of 7.5 : 2.5, and the prediction models were constructed in the training set by random forest. The prediction values of the models were measured via sensitivity, specificity, negative prediction value (NPV), positive prediction value (PPV), area under the curve (AUC), and accuracy. We found that NLR (OR = 1.261, 95% CI: 1.145–1.388), PLR (OR = 1.295, 95% CI: 1.152–1.445), and NPAR (OR = 1.476, 95% CI: 1.261–1.726) were associated with an increased risk, while PNI (OR = 0.035, 95% CI: 0.020–0.059) was associated with a decreased risk of one-year mortality in AKI patients. The AUC was 0.964 (95% CI: 0.959–0.969) in the training set based on PNI, age, gender, length of stay (LOS) in hospital, platelets (PLT), ethnicity, LOS in ICU, systolic blood pressure (SBP), diastolic blood pressure (DBP), heart rate, glucose, AKI stage, atrial fibrillation (AF), vasopressor, renal replacement therapy (RRT), and mechanical ventilation. The testing set was applied as the internal validation of the model with an AUC of 0.778 (95% CI: 0.754–0.801). In conclusion, PNI accompanied by age, gender, ethnicity, SBP, DBP, heart rate, PLT, glucose, AF, RRT, mechanical ventilation, vasopressor, AKI stage, LOS in ICU, and LOS in hospital exhibited a good predictive value for one-year mortality of AKI patients.

Hematological Ratios Are Associated with Acute Kidney Injury and Mortality in Patients That Present with Suspected Infection at the Emergency Department

The early recognition of acute kidney injury (AKI) is essential to improve outcomes and prevent complications such as chronic kidney disease, the need for renal-replacement therapy, and an increased length of hospital stay. Increasing evidence shows that inflammation plays an important role in the pathophysiology of AKI and mortality. Several inflammatory hematological ratios can be used to measure systemic inflammation. Therefore, the association between these ratios and outcomes (AKI and mortality) in patients suspected of having an infection at the emergency department was investigated. Data from the SPACE cohort were used. Cox regression was performed to investigate the association between seven hematological ratios and outcomes. A total of 1889 patients were included, of which 160 (8.5%) patients developed AKI and 102 (5.4%) died in <30 days. The Cox proportional-hazards model revealed that the neutrophil-to-lymphocyte ratio (NLR), segmented-neutrophil-to-monocyte ratio (SMR), and neutrophil-lymphocyte-platelet ratio (NLPR) are independently associated with AKI <30 days after emergency-department presentation. Additionally, the NLR, SMR and NLPR were associated with 30-day all-cause mortality. These findings are an important step forward for the early recognition of AKI. The use of these markers might enable emergency-department physicians to recognize and treat AKI in an early phase to potentially prevent complications.

Association between neutrophil-to-lymphocyte ratio and major postoperative complications after carotid endarterectomy: A retrospective cohort study

BACKGROUND

Carotid artery cross-clamping during carotid endarterectomy (CEA) may damage local cerebral perfusion and induce cerebral ischemia–reperfusion injury to activate local inflammatory responses. Neutrophil-to-lymphocyte ratio (NLR) is an indicator that reflects systemic inflammation. However, the correlation between NLR and complications after CEA remains unclear.

AIM

To investigate the association between NLR and major complications after surgery in patients undergoing CEA.

METHODS

This retrospective cohort study included patients who received CEA between January 2016 and July 2018 at Beijing Tiantan Hospital. Neutrophil and lymphocyte counts in whole blood within 24 h after CEA were collected. The primary outcome was the composite of major postoperative complications including neurological, pulmonary, cardiovascular and acute kidney injuries. The secondary outcomes included infections, fever, deep venous thrombosis, length of hospitalization and cost of hospitalization. Statistical analyses were performed using EmpowerStats software and R software.

RESULTS

A total of 224 patients who received CEA were screened for review and 206 were included in the statistical analyses; of whom, 40 (19.42%) developed major postoperative complications. NLR within 24 h after CEA was significantly correlated with major postoperative complications (P = 0.026). After confounding factors were adjusted, the odds ratio was 1.15 (95%CI: 1.03–1.29, P = 0.014). The incidence of major postoperative complications in the high NLR group was 8.47 times that in the low NLR group (P = 0.002).

CONCLUSION

NLR is associated with major postoperative complications in patients undergoing CEA.

Neutrophil-to-lymphocyte ratio is a marker for acute kidney injury progression and mortality in critically ill populations: a population-based, multi-institutional study

Backgrounds

Neutrophil-to-lymphocyte ratio (NLR), a surrogate marker of systemic response to physiological stress, is used for prognosis prediction in many diseases. However, the usefulness of this marker for predicting acute kidney injury (AKI) progression is unclear.

Methods

This retrospective study was based on the Chang Gung Research Database. Patients admitted to the intensive care unit with a diagnosis of stage 1 or 2 AKI were identified. The primary outcome was a composite of progression to stage 3 AKI, requirement of renal replacement therapy, or 14-day in-hospital mortality. The association between NLR and the primary outcome was examined using a logistic regression model and multivariable analysis. The nonlinearity and cutoff points of this relationship were determined using a restricted cubic spline model.

Results

A total of 10,441 patients were enrolled. NLR level at the time of stage 1–2 AKI diagnosis was a marker of adverse outcomes. After adjustment for confounders, NLR was independently associated with the composite outcome of AKI progression, renal replacement therapy, or mortality. The restricted cubic spline model revealed a J-shaped curve, with the lowest odds ratio for an NLR between 7 and 38. Subgroup analysis revealed linear and J-shaped relationships between NLR and the primary outcome in patients admitted to the intensive care unit for medical reasons and for cardiovascular surgery, respectively.

Conclusions

NLR is an independent marker of AKI progression and in-hospital mortality. Because it is readily available in daily practice, it might be used for risk stratification in the AKI population.

Graphic abstract

Supplementary Information

The online version contains supplementary material available at 10.1007/s40620-021-01162-3.

Dynamics in perioperative neutrophil-to-lymphocyte*platelet ratio as a predictor of early acute kidney injury following cardiovascular surgery

BACKGROUND

In this study, we applied a composite index of neutrophil-lymphocyte * platelet ratio (NLPR), and explore the significance of the dynamics of perioperative NLPR in predicting cardiac surgery-associated acute kidney injury (CSA-AKI).

METHODS

During July 1^st and December 31^th 2019, participants were prospectively derived from the 'Zhongshan Cardiovascular Surgery Cohort'. NLPR was determined using neutrophil counts, lymphocyte and platelet count at the two-time points. Dose-response relationship analyses were applied to delineate the non-linear odds ratio (OR) of CSA-AKI in different NLPR levels. Then NLPRs were integrated into the generalized estimating equation (GEE) to predict the risk of AKI.

RESULTS

Of 2449 patients receiving cardiovascular surgery, 838 (34.2%) cases developed CSA-AKI with stage 1 (n = 658, 26.9%), stage 2-3 (n = 180, 7.3%). Compared with non-AKI patients, both preoperative and postoperative NLPR were higher in AKI patients (1.1[0.8, 1.8] vs. 0.9[0.7,1.4], p < 0.001; 12.4[7.5, 20.0] vs. 10.1[6.4,16.7], p < 0.001). Such an effect was a 'J'-shaped relationship: CSA-AKI's risk was relatively flat until 1.0 of preoperative NLPR and increased rapidly afterward, with an odds ratio of 1.13 (1.06-1.19) per 1 unit. Similarly, patients whose postoperative NLPR value >11.0 were more likely to develop AKI with an OR of 1.02. Integrating the dynamic NLPRs into the GEE model, we found that the AUC was 0.806(95% CI 0.793-0.819), which was significantly higher than the AUC without NLPR (0.799, p < 0.001).

CONCLUSION

Dynamics of perioperative NPLR is a promising marker for predicting acute kidney injury. It will facilitate AKI risk management and allow clinicians to intervene early so as to reverse renal damage.

Development and External Validation a Novel Inflammation-Based Score for Acute Kidney Injury and Prognosis in Intensive Care Unit Patients

Purpose

We aimed to evaluate the predictive ability of an integrated score based on several inflammatory indices of acute kidney injury (AKI) in patients in the intensive care unit (ICU).

Patients and Methods

In this observational study, 2555 patients from the Medical Information Mart for Intensive Care III database were randomly assigned to the test set (n=1599) and internal validation set (n=656). Moreover, 412 coronary care unit patients from Zhongnan Hospital, Wuhan University were also included in the external validation set. The AKI-specific inflammatory index (ASII) was created using various inflammatory indices significantly associated with AKI. We further developed and validated two nomograms based on the ASII and other informative clinical features of AKI and prognosis.

Results

The ASII was calculated as 2.317×MLR+0.417×GPS+0.007×ALRI. In the training set, patients with a high ASII had a higher risk of incident AKI (odds ratio [OR], 5.33; 95% confidence index [CI], 3.60–7.88; P<0.001) than those with a low ASII with or without pre-existing chronic kidney disease. The nomograms for AKI and prognosis based on the ASII and other significant clinical characteristics had high predictive value in the prediction of AKI and prognosis in patients in the ICU. Moreover, the results in the internal validation set and in the external validation cohort were almost consistent with those in the training set.

Conclusion

The ASII is an AKI-specific tool based on the combination of available inflammatory indices. A high ASII is a strong predictor of a higher risk of AKI and worse survival outcomes in patients in the ICU.

The neutrophil-to-lymphocyte ratio as a marker of vasculitis activity, severe infection and mortality in anca-associated vasculitis: A retrospective study

INTRODUCTION

Anti-neutrophil cytoplasmic antibody-associated vasculitis (AAV) is a multisystemic disease. Despite the improvement in mortality rate since the introduction of immunosuppression, long-term prognosis is still uncertain not only because of the disease activity but also due to treatment associated adverse effects. The neutrophil-to-lymphocyte ratio (NLR) has been demonstrated as an inflammatory marker in multiple settings. In this study, we aimed to investigate the prognostic ability of the NLR in AAV patients.

METHODS

We conducted a retrospective analysis of the clinical records of all adult patients with AVV admitted to the Nephrology and Renal Transplantation Department of Centro Hospitalar Universitário Lisboa Norte from January 2006 to December 2019. NLR was calculated at admission. The outcomes measured were severe infection at 3 months and one-year mortality. The prognostic ability of the NLR was determined using the receiver operating characteristic (ROC) curve. A cut-off value was defined as that with the highest validity. All variables underwent univariate analysis to determine statistically significant factors that may have outcomes. Only variables which significantly differed were used in the multivariate analysis using the logistic regression method.

RESULTS

We registered 45 cases of AVV. The mean age at diagnosis was 67.5±12.1 years and 23 patients were male. The mean Birmingham Vasculitis Activity Score (BVAS) at presentation was 26.0±10.4. Twenty-nine patients were ANCA-MPO positive, 7 ANCA-PR3 positive and 9 were considered negative ANCA vasculitis. At admission, mean serum creatinine (SCr) was 4.9±2.5mg/dL, erythrocyte sedimentation rate (ESR) was 76.9±33.8mm/h, hemoglobin was 9.5±1.7g/dL, C-reactive protein was 13.2±5.8mg/dL and NLR was 8.5±6.8. Thirty-five patients were treated with cyclophosphamide, eight patients with rituximab for induction therapy. Twenty patients developed severe infection within the first three months after starting induction immunosuppression. In a multivariate analysis, older age (73.6±10.5 vs. 62.6±11.3, p=0.002, adjusted OR 1.08 [95% CI 1.01-1.16], p=0.035) and higher NLR (11.9±7.4 vs. 5.9±5.0, p=0.002, adjusted OR 1.14 [95% CI 1.01-1.29], p=0.035) were predictors of severe infection at 3 months. NLR ≥4.04 predicted severe infection at 3 months with a sensitivity of 95% and specificity of 52% and the AUROC curve was 0.0794 (95% CI 0.647-0.900). Nine patients died within the first year. Severe infection at 3 months was independently associated with mortality within the first year (OR 6.19 [95% CI 1.12-34.32], p=0.037).

CONCLUSIONS

NLR at diagnosis was an independent predictor of severe infection within the first 3 months after immunosuppression start, and severe infection within the first three months was consequently correlated with one-year mortality. NLR is an easily calculated and low-cost laboratory inflammation biomarker and can prove useful in identifying AAV patients at risk of infection and poorer prognosis.

Targeting Cytokine Storm in COVID-19: A Role of Online Hemodiafiltration with Asymmetric Cellulose Triacetate in Maintenance Hemodialysis Patients-A Report of 10 Cases

Early reports have suggested that maintenance hemodialysis (MHD) patients could be more susceptible to a severe course of COVID-19. Among the therapeutic approaches, the use of drugs that reduce the cytokine storm characteristic of this disease has been proposed. Some dialyzers, such as the new generation of asymmetric cellulose triacetate (ATA) membranes, could favor the effective elimination of medium-sized molecules and other inflammatory mediators. In this case series, we describe in depth the clinical, analytical, and radiological details, therapeutic aspects, and outcomes of the case series of 10 MHD patients of our dialysis unit, who tested positive for SARS-CoV-2 from 5 October to 30 November 2020. Furthermore, we evaluate the removal of hyperinflammatory parameters with the ATA membrane in postdilution online hemodiafiltration (OL-HDF) in these patients through a variety of biomarkers of systemic inflammation from the diagnosis until stripping. Biochemical blood analysis was carried out at baseline and at days 7 and 14 after diagnosis, respectively. 50% of the patients presented COVID-19 pneumonia and required hospital admission. Median hospitalization time was 21 days. A total of 4 patients developed severe pneumonia (3 of them died) and 1 patient developed moderate pneumonia. Patients who died (n = 3) were more likely to present bilateral pneumonia (100% vs 14.3%) at diagnosis and less reduction in interleukin 6 (IL-6) at day 14, as compared to those who survived. The use of the ATA membrane could be considered a therapeutic option, due to its immunomodulatory effect in MHD patients with SARS-CoV-2 infection, especially at the beginning of the disease, where the inflammatory component is predominant.

The neutrophil-to-lymphocyte ratio as a marker of vasculitis activity, severe infection and mortality in anca-associated vasculitis: A retrospective study

INTRODUCTION

Anti-neutrophil cytoplasmic antibody-associated vasculitis (AAV) is a multisystemic disease. Despite the improvement in mortality rate since the introduction of immunosuppression, long-term prognosis is still uncertain not only because of the disease activity but also due to treatment associated adverse effects. The neutrophil-to-lymphocyte ratio (NLR) has been demonstrated as an inflammatory marker in multiple settings. In this study, we aimed to investigate the prognostic ability of the NLR in AAV patients.

METHODS

We conducted a retrospective analysis of the clinical records of all adult patients with AVV admitted to the Nephrology and Renal Transplantation Department of Centro Hospitalar Universitário Lisboa Norte from January 2006 to December 2019. NLR was calculated at admission. The outcomes measured were severe infection at 3 months and one-year mortality. The prognostic ability of the NLR was determined using the receiver operating characteristic (ROC) curve. A cut-off value was defined as that with the highest validity. All variables underwent univariate analysis to determine statistically significant factors that may have outcomes. Only variables which significantly differed were used in the multivariate analysis using the logistic regression method.

RESULTS

We registered 45 cases of AVV. The mean age at diagnosis was 67.5±12.1 years and 23 patients were male. The mean Birmingham Vasculitis Activity Score (BVAS) at presentation was 26.0±10.4. Twenty-nine patients were ANCA-MPO positive, 7 ANCA-PR3 positive and 9 were considered negative ANCA vasculitis. At admission, mean serum creatinine (SCr) was 4.9±2.5mg/dL, erythrocyte sedimentation rate (ESR) was 76.9±33.8mm/h, hemoglobin was 9.5±1.7g/dL, C-reactive protein was 13.2±5.8mg/dL and NLR was 8.5±6.8. Thirty-five patients were treated with cyclophosphamide, eight patients with rituximab for induction therapy. Twenty patients developed severe infection within the first three months after starting induction immunosuppression. In a multivariate analysis, older age (73.6±10.5 vs. 62.6±11.3, p=0.002, adjusted OR 1.08 [95% CI 1.01-1.16], p=0.035) and higher NLR (11.9±7.4 vs. 5.9±5.0, p=0.002, adjusted OR 1.14 [95% CI 1.01-1.29], p=0.035) were predictors of severe infection at 3 months. NLR ≥4.04 predicted severe infection at 3 months with a sensitivity of 95% and specificity of 52% and the AUROC curve was 0.0794 (95% CI 0.647-0.900). Nine patients died within the first year. Severe infection at 3 months was independently associated with mortality within the first year (OR 6.19 [95% CI 1.12-34.32], p=0.037).

CONCLUSIONS

NLR at diagnosis was an independent predictor of severe infection within the first 3 months after immunosuppression start, and severe infection within the first three months was consequently correlated with one-year mortality. NLR is an easily calculated and low-cost laboratory inflammation biomarker and can prove useful in identifying AAV patients at risk of infection and poorer prognosis.

Systemic Inflammatory Markers Predict Detrimental Outcome of Urosepsis in Kidney Transplant Recipients

BACKGROUND

Urosepsis is a frequent cause of hospitalization among kidney transplant recipients (KTxR). Systemic inflammatory markers may reflect disease severity; nevertheless, their predictive value has not been evaluated in KTxRs.

AIMS

We sought to investigate the diagnostic and prognostic value of blood-derived systemic inflammatory markers during urosepsis in KTxR.

METHODS

We retrospectively enrolled 80 transplant recipients who were hospitalized between 2014 and 2017 due to urosepsis and followed for at least 1 year. Multiple parameters were calculated from medical records. The study endpoint was defined as death, graft loss, or a more than double serum creatinine level compared with baseline.

RESULTS

Seventeen patients reached an endpoint and presented at admission significantly lower total serum protein [g/dL] (5.0 ± 0.6 vs 6.0 ± 0.7) and higher urea [mg/dL] (161, 118-218 vs 80, 56-125), neutrophil-to-lymphocyte ratio (NLR) (20.0, 12.5-48.3 vs 12.9, 7.0-20.1), platelet-to-lymphocyte ratio (PLR) (447, 203-706 vs 231, 160-357), derived neutrophil-to-lymphocyte ratio (dNLR) (8.5, 5.6-10.4 vs 5.3, 2.9-8.5), and maximal Sequential Organ Failure Assessment (SOFA) score (6, 4-7 vs 3, 3-5). Among blood markers, NLR showed the strongest correlation with C-reactive protein, procalcitonin, creatinine, urea, and maximal SOFA score. The NLR cut-off value >15 predicted endpoint occurrence with 59% specificity and 75% sensitivity (area under the curve [AUC] 0.67, P = .038). The combined impact of NLR, urea, and total serum protein increased the prognostic precision (sensitivity 85% and specificity 84%, AUC = 0.88, P < .001).

CONCLUSIONS

The combined impact of NLR, urea, and total serum protein identifies KTxR who are at risk of a bad outcome after urosepsis and require more meticulous care.

Neutrophil-lymphocyte count ratio as a diagnostic marker for acute kidney injury: a systematic review and meta-analysis

BACKGROUND

The neutrophil-to-lymphocyte ratio (NLR) is calculated from the white cell differential blood count. Recently, NLR was identified as a potential biomarker for the prediction of acute kidney injury (AKI). We conducted this systematic review and meta-analysis to evaluate the diagnostic value of NLCR for AKI in adult patients.

METHODS

Studies in the PubMed, EMBASE, Web of Science and Cochrane Library databases were systematically searched from the date of database inception to February 28, 2019. The predictive value of NLR for AKI was evaluated by the pooled sensitivity, specificity, and summary receiver operating characteristic curve (SROC) analyses. Review Manager and Stata were used for all statistical analyses. The sources of potential heterogeneity were explored by a sensitivity analysis and subgroup analysis.

RESULTS

This meta-analysis returned 89 reports, of which 9 fulfilled the inclusion criteria, accounting for 9766 patients. Bivariate analysis yielded a mean sensitivity of 0.736 (95% CI 0.675-0.790) and specificity of 0.686 (95% CI 0.601-0.759). The SROC was 0.77 (95% CI 0.74-0.81). The studies had no significant heterogeneity (Q = 0.675, p = 0.357, I² = 0).

CONCLUSIONS

Our findings indicate that the NLR may be a reliable biomarker for the early detection of AKI. Our findings also provide important information and assistance for clinicians in the prediction of AKI.

Complete blood count in acute kidney injury prediction: a narrative review

Acute kidney injury (AKI) is a complex syndrome defined by a decrease in renal function. The incidence of AKI has raised in the past decades, and it is associated with negative impact in patient outcomes in the short and long term. Considering the impact of AKI on patient prognosis, research has focused on methods to assess patients at risk for developing AKI, diagnose subclinical AKI, and on prevention and treatment strategies, for which it is crucial an understanding of pathophysiology the of AKI. In this review, we discuss the use of easily available parameters found in a complete blood count to detect patients at risk for developing AKI, to provide an early diagnosis of AKI, and to predict associated patient outcomes.

Relation of neutrophil-to-lymphocyte ratio to acute kidney injury in patients with sepsis and septic shock: A retrospective study

BACKGROUND

The purpose of this study was to determine the association of the neutrophil-to-lymphocyte ratio (NLR) measured at the time of admission to intensive unit (ICU) with acute kidney injury (AKI) in patients with sepsis and septic shock. In addition, we investigated whether the NLR affects in-hospital mortality in septic AKI patients.

METHODS

In this retrospective study, a total of 222 adult patients with sepsis and septic shock were included, who were admitted to the ICU of Zhongnan Hospital of Wuhan University from January 2015 to December 2017. Sepsis and septic shock were diagnosed based on sepsis-3 consensus. AKI was diagnosed according to the KDIGO-AKI criteria. The primary outcome of the study was septic AKI. The secondary endpoint was in-hospital mortality of patients with septic AKI.

RESULTS

132 patients (59.46%) had AKI, and 64 (28.83%) died, of whom 55 (41.67%) in the AKI group and 9 (10.00%) in the non-AKI group. The NLR of the AKI group was significantly higher than that of the non-AKI group, and there was a statistically significant difference between the two groups (P < 0.001). Multivariate logistic regression analysis suggested that the NLR was independent predictors of septic AKI (OR = 1.047, 95% CI: 1.005-1.091, P = 0.026). The ROC curve showed that the AUC of the NLR for predicting septic AKI was 0.656 (95% CI 0.584-0.728, P < 0.001) and the cutoff value was 17.11 (sensitivity, 62.1%; specificity, 68.9%). However, no correlation was found between the NLR and in-hospital mortality in septic AKI patients.

CONCLUSION

NLR, a laboratory variable that is simple, widely available and inexpensive, was associated with the development of septic AKI and may be potential for risk stratification of septic AKI.

Neutrophil, lymphocyte and platelet ratio as a predictor of postoperative acute kidney injury in major abdominal surgery

BACKGROUND

Surgery is one of the leading causes of acute kidney injury (AKI) in hospitalized patients. Major abdominal surgery has the second higher incidences of AKI, after cardiac surgery. AKI results from a complex interaction between hemodynamic, toxic and inflammatory factors. The pathogenesis of AKI following major abdominal surgery is distinct from cardiac and vascular surgery. The neutrophil, lymphocytes and platelets (N/LP) ratio has been demonstrated as an inflammatory marker and an independent predictor for AKI and mortality after cardiovascular surgery. The aim of this study was to evaluate the prognostic ability of the post-operative N/LP ratio after major abdominal surgery.

METHODS

We cross-examined data of a retrospective analysis of 450 patients who underwent elective or urgent major nonvascular abdominal surgery at the Department of Surgery II of Centro Hospitalar Lisboa Norte from January 2010 to February 2011. N/LP ratio was determined using maximal neutrophil counts and minimal lymphocyte and platelet counts in the first 12 h after surgery. AKI was considered when developed within 48 h after surgery.

RESULTS

One-hundred and one patients (22.4%) developed AKI. Patients with higher N/LP ratio had an increased risk of developing postoperative AKI (6.36 ± 7.34 vs 4.33 ± 3.36, p < 0.001; unadjusted OR 1.1 (95% CI 1.04-1.16), p = 0.001; adjusted OR 1.05 (95% CI 1.00-1.10), p = 0.048). Twenty-nine patients died (6.44%). AKI was an independent predictor of mortality (20.8 vs 2.3%, p < 0.0001; unadjusted OR 11.2, 95% CI 4. 8-26.2, p < 0.0001; adjusted OR 3.56, 95% CI 1.0 2-12.43, p = 0.046). In a multivariate analysis higher N/LP ratio was not associated with increased in-hospital mortality.

CONCLUSION

Postoperative N/LP ratio was independently associated with AKI after major abdominal surgery, although there was no association with in-hospital mortality.

Acute Kidney Injury Definition and Diagnosis: A Narrative Review

Acute kidney injury (AKI) is a complex syndrome characterized by a decrease in renal function and associated with numerous etiologies and pathophysiological mechanisms. It is a common diagnosis in hospitalized patients, with increasing incidence in recent decades, and associated with poorer short- and long-term outcomes and increased health care costs. Considering its impact on patient prognosis, research has focused on methods to assess patients at risk of developing AKI and diagnose subclinical AKI, as well as prevention and treatment strategies, for which an understanding of the epidemiology of AKI is crucial. In this review, we discuss the evolving definition and classification of AKI, and novel diagnostic methods.

Prediction of acute kidney injury in cirrhotic patients: a new score combining renal, liver and inflammatory markers

Introduction

Acute kidney injury (AKI) is common in hospitalized patients with cirrhosis and is associated with poor prognosis. A risk prediction score combining values easily measured at admission could be valuable to stratify patients for prevention, monitoring and early intervention, ultimately improving patient care and outcomes. The aim of this study was to develop a risk score for AKI in a cohort of cirrhotic patients.

Patients and methods

We cross-examined the data from a retrospective analysis of 186 patients with cirrhosis admitted to the Gastroenterology and Hepatology Service of Centro Hospitalar Lisboa Norte from January 2003 to December 2005. AKI was defined as an increase in serum creatinine (SCr)≥0.3 mg/dL within 48 hours or a percentage increase in SCr≥50% from baseline. Neutrophil-to-lymphocyte ratio (NLR) was used as a marker for inflammation. A receiver operating characteristic (ROC) curve was produced to assess the discriminative ability of the variables. Cutoff values were defined as those with highest validity. The final AKI risk score model was assessed using the ROC curve.

Results

A total of 52 patients (28%) developed AKI. Higher baseline SCr (p<0.001), more severe liver disease as evaluated by the modified Model of End-stage Liver Disease (MELD)-Na score (p<0.001) and higher NLR (p=0.028) were independently associated with AKI. The area under the ROC (AUROC) curve for the prediction of AKI was 0.791 (95% CI 0.726–0.847) for SCr, 0.771 (95% CI 0.704–0.829) for modified MELD-Na and 0.757 (95% CI 0.689–0.817) for NLR. Cutoff values with the highest validity for predicting AKI were determined and defined as 0.9 for the SCr, 21.7 for the modified MELD-Na and 6 for the NLR. The risk score was created allowing 3 points if the SCr is higher than 0.9, 1 point if the modified MELD-Na is higher than 21.7 and 1 point if the NLR is higher than 6. The AUROC curve of the risk prediction score for AKI was 0.861. A risk score of ≥2 points predicts AKI in cirrhotic patients with a sensitivity of 88.5% and specificity of 72.4%.

Conclusion

A new score combining SCr, MELD-Na and NLR demonstrated a strong discriminative ability to predict AKI in cirrhotic patients.