Urinary neutrophil gelatinase-associated lipocalin, kidney injury molecule-1, N-acetyl-β-D-glucosaminidase levels and mortality risk in septic patients with acute kidney injury

Evaluation of the Effect of N-acetylcysteine in the Prevention of Colistin Nephrotoxicity in Critically Ill Patients: A Randomized Controlled Trial

Objective

The present study aimed to evaluate the efficacy of N-acetylcysteine (NAC) in preventing nephrotoxicity in critically ill patients receiving colistin.

Methods

In a randomized, controlled clinical trial, eligible participants receiving colistin were divided into two groups: the drug group (n = 24) and the control group (n = 24). In the drug group, 2 g of NAC was administered intravenously daily for 5 days, simultaneously with colistin. The patients in the control group received only colistin. Serum creatinine (SCr), blood urea nitrogen (BUN), and creatinine clearance (CrCl) at baseline and on each day, and the number of cases of acute kidney injury during the study were recorded. Urinary N-acetyl-beta-D-glucosaminidase (NAG) was determined before the start of treatment and on day 5. The study outcomes were the mortality rate, length of intensive care unit (ICU) stay, and NAG levels. Finally, the values were compared between the groups.

Findings

It was found that the 28-day mortality rate (P = 0.540) and length of ICU stay (P = 0.699) were not significantly improved by coadministration of intravenous N-acetylcysteine with colistin. SCr and BUN showed no significant reduction, and there were no changes in CrCl at the end of treatment. The changes in urinary NAG levels did not differ significantly between the two groups. There was also no difference in the stages of the RIFLE criteria (P = 0.641), and most patients were in the normal stage (58.3%).

Conclusion

Concomitant administration of intravenous NAC at a dose of 2 g daily does not prevent colistin-induced nephrotoxicity, 28-day mortality, and length of ICU stay in critically ill patients.

Clinical role of serum microRNA-155 in early diagnosis and prognosis of septic patients with acute kidney injury

BACKGROUND AND PURPOSE

Acute kidney injury (AKI) is a common complication in patients with sepsis, and early detection and timely treatment are crucial. This article aims to explore the clinical role of microRNA-155 (miR-155) in early diagnosis and prognosis evaluation of septic patients with acute kidney injury.

METHODS

We collected the blood samples of septic patients and measured the relative expression of serum miR-155 by RT-qPCR, and drew the receiver operating characteristic (ROC) curves to evaluate its early diagnosis for septic AKI.

RESULTS

The relative expression of miR-155 in the septic AKI was significantly higher than that in the septic non-AKI, and increased with the aggravation of renal function damage. The ROC curve of miR-155 for the diagnosis of septic AKI was 1.91 (95% CI: 1.61-2.19). When the optimal cut-off value of miR-155 expression was 2.37, its sensitivity for diagnosing septic AKI was 91.12% (95% CI: 80.41-95.07%), and its specificity was 84.52% (95% CI: 71.74-89.36%). Furthermore, the severity of kidney injury, SOFA score, APACHE II score and miR-155 were the risk factors affecting the prognosis of septic patients with AKI.

CONCLUSION

Serum miR-155 can be used as a novel biomarker for the early diagnosis of septic AKI, and also has important clinical value in the prognosis evaluation of septic patients with AKI.

Immunoregulatory mechanism of acute kidney injury in sepsis: A Narrative Review

Sepsis acute kidney injury (SAKI) is a common complication of sepsis, accounting for 26-50 % of all acute kidney injury (AKI). AKI is an independent risk factor for increased mortality risk in patients with sepsis. The excessive inflammatory cascade reaction in SAKI is one of the main causes of kidney damage. Both the innate immune system and the adaptive immune system are involved in the inflammation process of SAKI. Under the action of endotoxin, neutrophils, monocytes, macrophages, T cells and other complex immune network reactions occur, and a large number of endogenous inflammatory mediators are released, resulting in the amplification and loss of control of the inflammatory response. The study of immune cells in SAKI will help improve the understanding of the immune mechanisms of SAKI, and will lay a foundation for the development of new diagnostic and therapeutic targets. This article reviews the role of known immune mechanisms in the occurrence and development of SAKI, with a view to finding new targets for SAKI treatment.

The Effect of Dexmedetomidine on the Prognosis of Mechanically Ventilated Patients with Sepsis: A Meta-Analysis of Randomized Controlled Trials

BACKGROUND

Dexmedetomidine (Dex), as a new and highly selective α2 adrenergic receptor agonist, has been widely used in mechanically ventilated patients. In the present study, we used meta-analysis to study the effect of Dex on the prognosis of mechanically ventilated patients with sepsis.

METHODS

We searched PubMed, Cochrane clinical trial, EMBASE, Web of Science, and Chinese biomedical literature database to analyze relevant literature published from January 2000 to January 2021. We conducted the quality evaluation and data extraction for studies that met the inclusion criteria. RevMan 5.3 software was used to perform a meta-analysis of the 28-day mortality, hospital mortality, the length of ICU stay, and other adverse indicators.

RESULTS

Ten randomized controlled trials (RCTs) that met the inclusion criteria were finally included, including 9 RCTs in English and one in Chinese, with a total of 892 patients. Our meta-analysis results found that in mechanically ventilated patients with sepsis, Dex could significantly reduce the length of ICU stay (P=0.02), but did not reduce the patients' 28-day mortality (P=0.06), hospital mortality (P=0.17) and ventilator-free days (P=0.33). Furthermore, our meta-analysis results also found that Dex had no significant effect on the respiratory rate (P=0.53), heart rate (P=0.02), mean arterial pressure (P=0.63), the level of creatinine (P=0.82) and continuous renal replacement therapy (P=0.39) in mechanically ventilated patients with sepsis.

CONCLUSION

In mechanically ventilated patients with sepsis, Dex can reduce the length of ICU stay, but which cannot reduce the 28-day mortality, hospital mortality, and ventilator-free days.

Protective effect of N-acetylcysteine on acute lung injury in septic rats by inhibiting inflammation, oxidation, and apoptosis

Objectives

Acute lung injury (ALI) is a common comorbidity in patients with sepsis, and finding drugs that can effectively reduce its mortality is a hot spot in current research. The purpose of this study is to explore the protective mechanism of N-acetylcysteine (NAC) on ALI in septic rats.

Materials and Methods

We used NAC to intervene in septic rats to evaluate the plasma inflammatory factors and lung tissue pathological damage. Biochemical methods were used to determine the levels of oxidases in lung tissue, the expression of inducible nitric oxide synthase (iNOS) and endothelial nitric oxide synthase (eNOS) proteins, and observed lung tissue cell apoptosis.

Results

NAC pretreatment decreased the mortality of septic rats, improved lung tissue pathological damage, reduced the levels of tumor necrosis factor-α, interleukin-1β, interleukin-6, interleukin-8, and malondialdehyde, and increased activity of superoxide dismutase, glutathione peroxidase, and catalase. Moreover, NAC pretreatment significantly decreased iNOS protein expression and increased eNOS protein expression in lung tissue. Meanwhile, NAC significantly decreased the number of apoptosis and the levels of Bax and Caspase-3 mRNA and increased the level of Bcl-2 mRNA in the lung tissue of septic rats.

Conclusion

NAC protects ALI in septic rats by inhibiting inflammation, oxidative stress, and apoptosis.

Clinical value of serum miR-320-3p expression in predicting the prognosis of sepsis-induced acute kidney injury

BACKGROUND

For investigating the expression of miR-320-3p in children with sepsis-induced acute kidney injury (AKI) and its prognostic value.

METHODS

A total of 142 patients were grouped into a survival group (n = 95) and death group (n = 47), which was based on their 28-day survival. Serum degrees of miR-320-3p, neutrophil gelatinase-associated lipid carrier protein (NGAL) and kidney injury molecule-1 (KIM-1) were detected. The Acute Physiology and Chronic Health scoring system Ⅱ (APACHE Ⅱ) marks were recorded. Target gene forecast and functional enrichment discussion of miR-320-3p were performed, and a protein-protein interaction (PPI) network diagram was plotted by applying bioinformatics methods. Multivariate logistic regression, ROC curve and Pearson correlation analysis were applied.

RESULTS

The death group showed greatly higher serum levels of miR-320-3p, KIM-1 and APACHE Ⅱ scores than the survival group (p < 0.01). Multivariate logistic regression analysis showed that levels of miR-320-3p, NGAL, KIM-1 and APACHE Ⅱ scores were independent risk elements for death in sepsis children with AKI (p < 0.01). According to ROC curve analysis, the region under the curve (0.963, 95% CI: 0.908-0.996) of miR-320-3p, NGAL, KIM-1 levels and APACHE Ⅱ scores combined to forecast the death of kids suffering from sepsis and AKI were the biggest. According to correlation analysis, the expression degree of serum miR-320-3p in the death group was positively correlated with NGAL, KIM-1 and APACHE Ⅱ scores (all p < 0.01).

CONCLUSIONS

The expression level of serum miR-320-3p in children with sepsis-induced AKI was significantly increased, and the combination of NGAL, KIM-1 and APACHE Ⅱ scores has good value for prognosis prediction in children.

Assessment of the diagnostic ability of rifle classification and neutrophil gelatinase-associated lipocalin biomarker in detecting acute kidney injury in newborns at the intensive care unit

Introduction/Objective. This study was designed to demonstrate the association of the RIFLE classification and neutrophil gelatinase-associated lipocalin (NGAL) in predicting of newborns with AKI. Methods. This was a prospective study. We included 100 newborns suspected of having a kidney injury. These newborns were admitted to the Intensive Care Unit (ICU) at the University Clinic of Pediatrics from the period of two years. The severity of the disease was determined by RIFLE classification. The biochemical marker NGAL was included in this study because it is an early biomarker of AKI in newborns. The statistical processing of the material was by methods of descriptive statistics. Results. The prevalence rate of AKI was 6.25%, but according to the RIFLE classification the prevalence was 8.7%. According to RIFLE classification, we reported "risk" in 36%, "injury? in 50% and ?failure" in 14% of newborns with AKI. In newborns with perinatal asphyxia, kidney injury was seen in 34% and 30%, making perinatal asphyxia the most common predisposing factor. The difference in average value from the SNAPPE 2 result in newborns with AKI and the control group without AKI was confirmed to be significant (p < 0.001). Also, there was a significant difference p<0.001 between serum creatinine and urinary NGAL values NGAL, on the day they were admitted to the ICU. Conclusion. In newborns hospitalized in the ICU, acute renal injury is a serious condition. We could identify kidney injury and follow up the progression of the disease by using RIFLE classification. The need for early diagnosis of kidney injury, in a period when the disease is not clinically manifest, in the first hours of its occurrence, is provided by NGAL.

Combining renal cell arrest and damage biomarkers to predict progressive AKI in patient with sepsis

Background

Sepsis is the most common trigger for AKI and up to 40% of mild or moderate septic AKI would progress to more severe AKI, which is associated with significantly increased risk for death and later CKD/ESRD. Early identifying high risk patients for AKI progression is a major challenge in patients with septic AKI.

Methods

This is a prospective, multicenter cohort study which enrolled adult patients with sepsis and initially developed stage 1 or 2 AKI in the intensive care unit from January 2014 to March 2018. AKI was diagnosed and staged according to 2012 KDIGO-AKI guidelines. Renal cell arrest biomarkers (urinary TIMP2*IGFBP7, u[TIMP-2]*[IGFBP7]) and renal damage biomarkers (urinary KIM-1[uKIM-1] and urinary IL-18 [uIL-18]) were measured at time of AKI clinical diagnosis, and the performance of biomarkers for predicting septic AKI progression alone or in combination were evaluated. The primary outcome was AKI progression defined as worsening of AKI stage. The secondary outcome was AKI progression with subsequent death during hospitalization.

Results

Among 433 screened patients, 149 patients with sepsis and stage 1 or 2 AKI were included, in which 63 patients developed progressive AKI and 49 patients subsequently died during hospitalization. u[TIMP-2]*[IGFBP7], uKIM-1 and uIL-18 independently predicted the progression of septic AKI in which u[TIMP-2]*[IGFBP7] showed the greatest AUC (0.745; 95%CI, 0.667-0.823) as compared to uKIM-1 (AUC 0.719; 95%CI 0.638-0.800) and uIL-18 (AUC 0.619; 95%CI 0.525-0.731). Combination of u[TIMP-2]*[IGFBP7] with uKIM-1 improved the performance of predicting septic AKI progression with AUC of 0.752. u[TIMP-2]*[IGFBP7], alone or combined with uKIM-1/uIL-18, improved the risk reclassification over the clinical risk factor model alone both for the primary and secondary outcomes, as evidenced by significant category-free net reclassification index.

Conclusions

Combination of renal cell arrest and damage biomarkers enhanced the prediction of AKI progression in patients with sepsis and improved risk reclassification over the clinical risk factors.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12882-021-02611-8.

Longitudinal study of physical activity with various methods in maintenance hemodialysis patients

INTRODUCTION

The purpose was to make longitudinal measurements of physical activity and study whether physical activity decreases over time in maintenance hemodialysis (MHD) patients.

METHODS

This was an observational study, where MHD patients were considered in a 12-month follow-up. Laboratory variables and physical activity were tested three times over 12-months in 124 hemodialysis patients. Physical activity was measured using the Human Activity Profile (HAP), the Stanford 7-day Physical Activity Recall Questionnaire (PAR), and walking speed. Repeated measure variance analysis was used to analyze changes of physical activity. The Bonferroni method was used to do pairwise comparisons.

FINDINGS

The proportion of decreased physical activity increased (P < 0.05). The maximal activity score (MAS), adjusted activity score (AAS), HAP dimension scores, and walking speed all decreased at the three time points studied (P < 0.001). At the same time, moderate physical activities and PAR values changed at three time points (P < 0.05). Pairwise comparisons showed that between the baseline and the 6-month follow-up, MAS, AAS, the scores of personal/household work, entertainment/social, independent exercise, leg effort, and back effort, all decreased(P < 0.05). Between the baseline and the 12-month follow-up, and between the 6-month follow-up and the 12-month follow-up, all the scores of HAP and walking speed decreased significantly (P < 0.001). Between the baseline and the 6-month follow-up, moderate physical activities and PAR values increased (P < 0.05). However, between the baseline and the 12-month follow-up, and between the 6-month follow-up and the 12-month follow-up, moderate physical activities and PAR did not change statistically.

CONCLUSION

Physical activity decreased in hemodialysis patients in the 12-month follow-up.

Pretreatment with S-Nitrosoglutathione Attenuates Septic Acute Kidney Injury in Rats by Inhibiting Inflammation, Oxidation, and Apoptosis

Objective

We aimed to investigate the protective effect of s-nitrosoglutathione (SNG) pretreatment on acute kidney injury (AKI) in septic rats.

Methods

We constructed a rat model of sepsis by cecal ligation and puncture and observed the survival of the rats. We obtained kidney and blood samples from rats, observed the pathological damage to the kidney tissues, and evaluated kidney function and the expression levels of inflammatory factors. We also detected the expression of induced nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) in the kidneys by immunohistochemistry and evaluated the apoptosis of kidney tubular epithelial cells (KTEC) by TUNEL.

Results

Pretreatment with SNG significantly reduced the mortality of septic rats, attenuated kidney pathological damage, and decreased the levels of serum creatinine, plasma neutrophil gelatinase-associated lipocalin, and plasma kidney injury molecule-1. Moreover, SNG pretreatment decreased the levels of TNF-α and IL-1β in serum and kidney and reduced the expressions of NO, iNOS, PGE2, and COX-2 in the kidneys. Furthermore, pretreatment with SNG significantly reduced the apoptotic rate of KTEC and decreased the levels of caspase-3 and Bax mRNA, but increased the level of Bcl-2 mRNA.

Conclusion

Pretreatment with SNG has a protective effect on AKI in septic rats, and the specific mechanisms are related to inhibition of inflammation, oxidation, and apoptosis.

Chrysophanol Relieves Cisplatin-Induced Nephrotoxicity via Concomitant Inhibition of Oxidative Stress, Apoptosis, and Inflammation

Cisplatin (CDDP) is one of the most frequently prescribed chemotherapy medications. However, its nephrotoxicity which often leads to acute kidney injury (AKI), greatly limits its clinical application. Chrysophanol (CHR), a mainly active anthraquinone ingredient, possesses various biological and pharmacological activities. In this study, we aimed to investigate the underlying protective mechanisms of CHR against CDDP-induced AKI (CDDP-AKI) using C57BL/6 mouse and human proximal tubule epithelial cells. In vivo, we found that pre-treatment with CHR greatly relieved CDDP-AKI and improved the kidney function and morphology. The mechanistic studies indicated that it might alleviate CDDP-AKI by inhibiting oxidative stress, apoptosis, and IKKβ/IκBα/p65/transcription factor nuclear kappa B (NF-κB) inflammation signaling pathway induced by CDDP. Moreover, we found that the cell viability of HK2 cells reduced by CDDP was partially rescued by CHR pre-incubation. Flow cytometry results further indicated that CHR pre-incubation suppressed CDDP induced cellular reactive oxygen species (ROS) generation and inhibited cell apoptosis in a dose-dependent manner. In summary, our results suggested that CHR might be a novel therapy for CDDP-induced AKI.

Serum and Urine Neutrophil Gelatinase-Associated Lipocalin Levels Measured at Admission Predict Progression to Chronic Kidney Disease in Sepsis-Associated Acute Kidney Injury Patients

Background

To evaluate the ratio of acute kidney injury (AKI) to chronic kidney disease (CKD) in sepsis-associated acute kidney injury (SA-AKI) patients of the intensive care unit (ICU) and predictive value of neutrophil gelatinase-associated lipocalin (NGAL) measured at the admission time in the progression of AKI to CKD.

Methods

A study of 121 consecutive adult patients admitted to the intensive care unit (ICU) diagnosed as SA-AKI. AKI and CKD were defined based on Kidney Disease: Improving Global Outcomes (KDIGO) criteria. Glomerular filtration rate (GFR) was calculated by the CKD-EPI formula. Serum and urine NGAL was measured using the BioVendor Human Lipocalin-2/NGAL ELISA with a blood sample taken at hospital admission time.

Results

The ratio of AKI to CKD in SA-AKI patients was 22.3%. Mean concentration of serum and urine NGAL in AKI to the CKD group was 790.99 ng/ml and 885.72 ng/ml, higher significantly than those of recovery patients (351.86 ng/ml and 264.68 ng/ml), p < 0.001. eGFR, both serum and urine NGAL had a predictive value for AKI to CKD (eGFR: AUC = 0.857, Se = 74.1%, Spe = 92.6%, p < 0.001. Serum NGAL: AUC = 0.868, Se = 77.8%, Spe = 91.5%. Urine NGAL: AUC = 0.869, Se = 77.8%, Spe = 92.6%, p < 0.001.

Conclusion

Serum and urine NGAL, measuring at hospital admission time, were good prognostic biomarkers of AKI to CKD in SA-AKI patients.

Biomarkers of Kidney Injury in Very-low-birth-weight Preterm Infants: Influence of Maternal and Neonatal Factors

BACKGROUND/AIM

Acute kidney injury is an important cause of mortality in very-low-birth-weight (VLBW) preterm infants. As in the general population, the detection of renal damage cannot rely on the measurement of serum creatinine, since it has been demonstrated to be a weak predictor and a delayed indicator of kidney function deterioration. However, several candidate biomarkers have failed to prove sufficient specificity and sensitivity for a routine clinical use because of the poor awareness of their biological role. This study was aimed to investigate the impact of different maternal and neonatal conditions on several renal biomarkers in VLBW preterm infants during the first week of life.

PATIENTS AND METHODS

Preterm infants<32 weeks' gestation and <1500g were enrolled. We measured urinary biomarkers kidney injury molecule 1 (KIM-1), neutrophil gelatinase-associated lipocalin (NGAL), cystatin C, epidermal growth factor (EGF) and osteopontin (OPN) on the 1st, 3rd, and 7th day after birth.

RESULTS

Thirty-tree infants were included. The multivariate analysis showed a significant association between gestational age, the presence of patent ductus arteriosus, antenatal maternal hypertension and the levels of urinary biomarkers.

CONCLUSION

There is a possible relation between early biomarkers of renal injury and antenatal, perinatal and post-natal characteristics in VLBW preterm infants during the first week of life.

Role of the Furosemide Stress Test in Renal Injury Prognosis

Risk stratification and accurate patient prognosis are pending issues in the management of patients with kidney disease. The furosemide stress test (FST) has been proposed as a low-cost, fast, safe, and easy-to-perform test to assess tubular integrity, especially when compared to novel plasma and urinary biomarkers. However, the findings regarding its clinical use published so far provide insufficient evidence to recommend the generalized application of the test in daily clinical routine. Dosage, timing, and clinical outcomes of the FST proposed thus far have been significantly different, which further accentuates the need for standardization in the application of the test in order to facilitate the comparison of results between series. This review will summarize published research regarding the usefulness of the FST in different settings, providing the reader some insights about the possible implications of FST in clinical decision-making in patients with kidney disease and the challenges that research will have to address in the near future before widely applying the FST.

Down-regulation of miR-133a-3p protects lung tissue against sepsis-induced acute respiratory distress syndrome by up-regulating SIRT1

Introduction

MicroRNA-133a-3p (miR-133a-3p) is a potential gene regulator having an important role in the process of inflammation and lung injury. The present work studied the role of miR-133a-3p in sepsis-mediated acute respiratory distress syndrome (ARDS) and the mechanism involved.

Material and methods

C57BL/6 mice were selected for the study. Protein expression of Bcl-2, cleaved caspase-3 and Bax was assessed by western blot analysis. Expression of mRNA was assessed by RT-PCR. Effects of inflammation were studied by myeloperoxidase (MPO) activity. Quantification of albumin was done by measuring the albumin conjugated with Evan's blue. The alveolar macrophages were separated from the lungs of mice by the bronchoalveolar lavage procedure and were submitted to sepsis challenge in vitro; the macrophages were treated with lipopolysaccharide (LPS).

Results

Treatment of LPS resulted in upregulation of miR-133a-3p in alveolar macrophages. Suppression of miR-133a-3p halted the over-expression of inflammatory cytokines in macrophages and caused remission of histopathologic changes. The ARDS lungs showed a decrease in levels of proinflammatory cytokines and an increase in levels of apoptotic protein, establishing the protective role for miR-133a-3p. The results suggested sirtuin 1 (SIRT1) as a potential target of miR-133a-3p in the macrophages, also showing that expression of SIRT1 was inversely associated with expression of miR-133a-3p. The protective effect of miR-133a-3p down-regulation in LPS-mediated alveolar macrophages and sepsis-induced ARDS could be corrected by a SIRT1 inhibitor.

Conclusions

Down-regulation of miR-133a-3p may exert a protective effect on lung tissue against sepsis-mediated ARDS by up-regulating the levels of SIRT1 via suppressing the inflammatory response and inhibiting the cellular apoptosis in lung tissues.

Effect of lymphocyte-to-monocyte ratio on survival in septic patients: an observational cohort study

Introduction

The purpose of the present study was to evaluate the potential relationship of lymphocyte-to-monocyte ratio (LMR) with outcomes of septic patients at intensive care unit (ICU) admission.

Material and methods

3087 septic patients were included in the final cohort by using the Medical Information Mart for Intensive Care (MIMIC) database. We evaluated the association of different groups of LMRmax with 28-day survival and 1-year survival via Kaplan-Meier (K-M) analysis and Cox regression analysis. Subgroups analysis of LMRmax was performed to further explore the effect of LMRmax on survival.

Results

According to the optimal cut-off value, the cohort was divided into low-LMRmax and high-LMRmax groups. The 28-day and 1-year survival rates were 47.9% and 19.9%, respectively, in the low-LMRmax group, and 60.4% and 25.9%, respectively, in the high-LMRmax group. Univariate logistic regression and K-M analyses revealed that the 28-day and 1-year survival rates of the high-LMRmax group were higher than those of the low-LMRmax group (both p < 0.001). A subgroup analysis of LMRmax identified a significant stepwise decrease in the risk of death at 28 days and 1 year from group 1 to group 4 (LMRmax increased gradually) after adjustment for multiple variables.

Conclusions

We report for the first time that a lower LMRmax value is independently predictive of a poor prognosis in septic patients. Therefore, as an inexpensive and readily available indicator, LMRmax may facilitate stratification of prognosis in septic patients.

Prognostic value of serum and urine kidney injury molecule-1 in infants with urinary tract infection

Introduction

Kidney injury molecule-1 (KIM-1) is an important diagnostic and prognostic marker in acute kidney injury and chronic kidney disease of various aetiologies. The aim of the study was to evaluate the usefulness of serum KIM-1 (sKIM-1) and urine KIM-1 (uKIM-1) for predicting febrile and non-febrile urinary tract infection (UTI) in infants.

Material and methods

A prospective study included 101 children divided into three groups: febrile UTI 49 children, non-febrile UTI 22 children, and healthy controls 30 children. The following laboratory tests were performed: sKIM-1, uKIM-1, white blood count (WBC), C-reactive protein (CRP), and procalcitonin (PCT).

Results

Median levels of sKIM-1 were significantly higher in the febrile and non-febrile UTI group compared to the healthy controls (both p < 0.05). Mean levels of uKIM-1 were significantly lower in the febrile UTI group compared to the non-febrile UTI group and healthy controls (p < 0.001 and p < 0.0001, respectively). Univariate logistic regression analysis has demonstrated a positive association of sKIM-1 with febrile and non-febrile UTI (both p < 0.05), and negative association uKIM-1 with febrile UTI (p < 0.0001). Receiver operating curve (ROC) analysis showed good diagnostic profiles of uKIM-1 with a best cut-off value of 2.4 ng/ml and sKIM-1 with a best cut-off value of 3.88 ng/ml for predicting febrile UTI (area under the curve [AUC] 0.82 and 0.67, sensitivity 73% and 63%, specificity 86% and 80%, respectively).

Conclusions

sKIM-1 can be useful for predicting febrile UTI. We do not recommended use of uKIM-1 as a marker of febrile UTI because of its negative association with febrile UTI. Both markers are not useful for predicting non-febrile UTI.

S-nitrosoglutathione protects lipopolysaccharide-induced acute kidney injury by inhibiting toll-like receptor 4-nuclear factor-κB signal pathway

OBJECTIVES

To investigate the therapeutic effects and mechanisms of S-nitrosoglutathione (SNG) on acute kidney injury (AKI) induced by lipopolysaccharide (LPS).

METHODS

We established an AKI model by intraperitoneal administration of LPS in mice and LPS-induced human kidney (HK-2) cells in vitro. We obtained the kidney tissues from mice for histopathological examination, examined inflammatory cytokines by enzyme-linked immunosorbent assay and measured the expression levels of toll-like receptor 4-nuclear factor-κB (TLR4-NF-κB) signal pathway-related proteins by Western blotting.

KEY FINDINGS

Pretreatment of SNG effectively improved the kidney function, reduced the pathological damage score of kidney in mice and decreased the expression levels of IL-1β, IL-6 and TNF-α in a dose-dependent manner in vivo and in vitro. Furthermore, pretreatment of SNG also repressed TLR4, phosphorylated NF-κB IκBα, IKKβ and p65 expression levels in HK-2 cells induced by LPS.

CONCLUSIONS

S-nitrosoglutathione attenuates the severity of LPS-induced AKI by inhibiting the TLR4-NF-κB signalling pathway and may act as a protective agent for septic AKI.