Exploring systemic inflammation in children with chronic kidney disease: correlates of interleukin 6.

BACKGROUND: Systemic inflammation (SI) is linked to chronic kidney disease (CKD) progression and multiple complications. Data regarding SI biomarkers in pediatric patients are scarce. This case-control and cross-sectional study investigates the correlation of neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR), total iron binding capacity (TIBC) and serum albumin to serum interleukin-6 (IL-6). METHODS: NLR and PLR were measured in 53 patients (median age: 12.9 years), including 17 on dialysis and 36 with a median glomerular filtration rate of 39 ml/min/1.73m2, and in 25 age and sex-matched healthy controls. Iron profile, serum albumin and IL-6 were measured in the patient group. IL-6 levels > 3rd quartile were classified as high. RESULTS: Patients presented higher NLR and PLR and particularly those on dialysis (p < 0.001 and p = 0.001). We observed a significant correlation between natural logarithm (ln) of IL-6 (lnIL-6) and NLR (rs = 0.344, p = 0.014), serum albumin (rs = -0.350, p = 0.011) and TIBC (rs = -0.345, p = 0.012) after adjustment for CKD stage, while the correlation between lnIL-6 and PLR was not significant (rs = 0.206, p = 0.151). Combination of NLR, serum albumin and TIBC predicted high IL-6 (13 patients) with an AUC of 0.771 (95% CI 0.608-0.943). Pairing of NLR ≥ 1.7 and TIBC ≤ 300 µg/dL exhibited the highest sensitivity (76.9%), while incorporating serum albumin ≤ 3.8 g/dL along with them achieved the highest specificity (95%) for detecting high IL-6 levels. CONCLUSION: Both NLR and PLR levels increase in CKD, especially in patients on chronic dialysis. NLR, rather than PLR, along with TIBC and serum albumin, are associated with IL-6 in pediatric CKD.

Association Between Adipokine Profile, Systemic Inflammation, Muscle and Protein Energy Wasting in Children With Chronic Kidney Disease.

OBJECTIVES: This cross-sectional study explores the association of adipokines and interleukin-6 (IL-6) with muscle and protein energy wasting (PEW) in children with chronic kidney disease (CKD). METHODS: We measured serum adiponectin, leptin, resistin and IL-6 in 53 patients with CKD stage 3-5. Lean tissue (LTI) and fat tissue index (FTI) were estimated by bioimpedance analysis spectroscopy. PEW was defined as muscle wasting [LTI adjusted to height age (LTI HA) z-score < -1.65 SD) and at least 2 of the following: reduced body mass [body mass index adjusted to height age (BMI HA) z-score < -1.65 SD), poor growth [height z-score < -1.88 SD], questionnaire-based decreased appetite, and serum albumin ≤3.8 g/dL. RESULTS: PEW, observed in 8 (15.1%) patients, was more prevalent in CKD stage 5 (P = .010). Among the adipokines, adiponectin, and resistin levels were significantly higher in CKD stage 5 (P < .001, P = .005). Adiponectin was correlated to LTI HA z-score (Rs = -0.417, P = .002), leptin to FTI z-score (Rs = 0.620, P < .001), while no correlation was observed between resistin and body composition parameters. Resistin was the only adipokine correlated to IL-6 (Rs = 0.513, P < .001). After adjustment for CKD stage and patient age, PEW was associated with adiponectin and IL-6 rise by 1 µg/mL and 10 pg/mL respectively (odds ratio (OR) 1.240, 95% confidence interval (CI) 1.040, 1.478 and OR 1.405, 95% CI 1.075-1.836) but not with leptin, while resistin association with PEW lost its significance. CONCLUSIONS: In pediatric CKD, adiponectin is associated with muscle wasting, leptin with adiposity and resistin with systemic inflammation. Adiponectin and cytokine IL-6 may serve as PEW biomarkers.

Fibroblast growth-factor 23 and vitamin D are associated with iron deficiency and anemia in children with chronic kidney disease.

BACKGROUND: This cross-sectional study investigates the association of fibroblast growth-factor 23 (FGF23) and other bone mineral parameters with iron status and anemia in pediatric chronic kidney disease (CKD). METHODS: Serum calcium, phosphorus, 25-hydroxyvitamin D (25(OH)D), intact parathormone, c-terminal FGF23, a-Klotho, iron (Fe), ferritin, unsaturated iron-binding capacity, and hemoglobin (Hb) were measured in 53 patients from 5 to 19 years old with GFR < 60 mL/min/1.73 m2. Transferrin saturation (TSAT) was calculated. RESULTS: Absolute (ferritin ≤ 100 ng/mL, TSAT ≤ 20%) and functional iron deficiency (ferritin > 100 ng/mL, TSAT ≤ 20%) were observed in 32% and 7.5% of patients, respectively. In CKD stages 3-4 (36 patients), lnFGF23 and 25(OH)D were correlated with Fe (rs = - 0.418, p = 0.012 and rs = 0.467, p = 0.005) and TSAT (rs = - 0.357, p = 0.035 and rs = 0.487, p = 0.003) but not to ferritin. In this patient group, lnFGF23 and 25(OH)D were correlated with Hb z-score (rs = - 0.649, p < 0.001 and rs = 0.358, p = 0.035). No correlation was detected between lnKlotho and iron parameters. In CKD stages 3-4, in multivariate backward logistic regression analysis, including bone mineral parameters, CKD stage, patient age, and daily alphacalcidol dose as covariates, lnFGF23 and 25(OH)D were associated with low TSΑΤ (15 patients) (OR 6.348, 95% CI 1.106-36.419, and OR 0.619, 95% CI 0.429-0.894, respectively); lnFGF23 was associated with low Hb (10 patients) (OR 5.747, 95% CI 1.270-26.005); while the association between 25(OH)D and low Hb did not reach statistical significance (OR 0.818, 95% CI 0.637-1.050). CONCLUSIONS: In pediatric CKD stages 3-4, iron deficiency and anemia are associated with increased FGF23, independently of Klotho. Vitamin D deficiency might contribute to iron deficiency in this population. A higher resolution version of the Graphical abstract is available as Supplementary information.

Serum-Targeted HILIC-MS Metabolomics-Based Analysis in Infants with Ureteropelvic Junction Obstruction.

Ureteropelvic junction obstruction (UPJO) constitutes the predominant cause of obstructive nephropathy in both neonates and infants. Fundamental questions regarding UPJO's mechanism, assessment, and treatment still remain unanswered. The aim of the present study was to elucidate potential differences through serum metabolic profiling of surgical cases of infants with UPJO compared to both nonsurgical cases and healthy age-matched controls. Early diagnosis of renal dysfunction in this cohort based on highlighted biomarkers was the ultimate goal. Thus, serum samples were collected from 20 patients preoperatively, 19 patients with mild stenosis treated conservatively, and 17 healthy controls. All samples were subjected to targeted metabolomics analysis by hydrophilic interaction liquid chromatography coupled to mass spectrometry (HILIC LC-MS/MS). Both univariate and multivariate statistical analyses were performed. Principal component analysis (PCA) and orthogonal partial least squares-discriminant analysis (OPLS-DA) score plots showed that the studied groups differed significantly, with a panel of metabolites, including creatinine, tryptophan, choline, and aspartate, distinguishing patients who required surgery from those followed by systematical monitoring as well as from healthy controls, showing high performance as indicators of UPJO disease.

Causes of double-negative T-cell lymphocytosis in children and adults.

AIMS: The causes and diagnosis of 'double-negative' (CD3+CD4-CD8-) T-cell lymphocytosis are not well studied. We aimed to define the causes of double-negative T-cell lymphocytosis in children and adults, and to identify simple clinical and laboratory features that would help to differentiate between the underlying conditions. METHODS: We collected clinical and laboratory data on 10 children and 30 adults with significantly increased peripheral-blood double-negative T-cells (>10% of total lymphocytes). We identified conditions associated with double-negative T-lymphocytosis with flow cytometry, peripheral-blood morphology and T-cell receptor-gene rearrangement studies. Patients were assigned to diagnostic categories on the basis of these test results. RESULTS AND CONCLUSIONS: The causes of double-negative T-cell lymphocytosis in children were autoimmune lymphoproliferative syndrome (ALPS) and reactive γ/δ Τ-lymphocytosis. T-cell large granular lymphocyte (T-LGL) leukaemia, reactive γ/δ T-lymphocytosis and hepatosplenic T-cell lymphoma (HSTL) were the the most common disorders underlying double-negative T-cell lymphocytosis in adults. Less common causes included hypereosinophilic syndrome, peripheral T-cell lymphoma, ALPS and monoclonal, double-negative T-lymphocytosis of uncertain significance. CD5/CD7/Vδ2 expression and absolute double-negative lymphocyte count (<1.8×109/L) were useful discriminators for distinguishing patients with reactive γ/δ T-lymphocytosis from those with γ/δ lymphoproliferative disorders. Differentiating between γ/δ T-LGL and HSTL can be difficult. Expression of CD57 and cellular morphology (pale cytoplasm with distinct granules) would support a diagnosis of γ/δ T-LGL.

The role of urinary NGAL and serum cystatin C in assessing the severity of ureteropelvic junction obstruction in infants.

BACKGROUND: The ideal management of ureteropelvic junction obstruction (UPJO) remains debatable. This prospective case-control study aimed to investigate if urinary levels of Neutrophil Gelatinase-Associated Lipocalin (NGAL) and serum levels of cystatin C could distinguish surgical from non-surgical cases of UPJO and if they could detect earlier impairment of renal function. METHODS: Biomarkers were measured in the following age-matched groups: (a) 22 infants with surgical UPJO, at initial diagnosis and 12 months postoperatively (groups A1 and A2, respectively); (b) 19 infants with non-surgical UPJO (group B); and (c) 17 controls (group C). Based on serum cystatin C levels, estimated glomerular filtration rate (eGFR) was calculated. RESULTS: Urinary NGAL (uNGAL) was significantly higher in group A1 vs. group A2 (p = 0.02) and in group A1 vs. group C (p = 0.03), whereas there was no statistically significant difference between groups A2 and C (p = 0.77). Likewise, cystatin C levels were significantly higher in group A1 vs. group A2 and in group A1 vs. group C (p = 0.004 and p = 0.02, respectively), but no statistically significant difference between groups A2 and C (p = 0.82). uNGAL and serum cystatin C did not differ between groups B and A, nor did they differ between groups B and C. Cystatin C levels and eGFR of group A1 were significantly higher than those of group A2 and group C (p = 0.0001 and p = 0.02, respectively). CONCLUSION: It seems that NGAL and cystatin C are able to distinguish patients who were treated surgically from healthy controls, and their levels appear to improve significantly following surgery.

Interference of bone marrow CD56+ mesenchymal stromal cells in minimal residual disease investigation of neuroblastoma and other CD45- /CD56+ pediatric malignancies using flow cytometry.

BACKGROUND: Bone marrow (BM) samples obtained from minimal residual disease (MRD)-negative children with B-cell acute lymphoblastic leukemia (B-ALL) were used in our laboratory as negative biological controls for the development of a neuroblastoma (NBL) flow-cytometric (FC) protocol. The accidental, but systematic, identification of rare cell populations (RCP) mimicking NBL cells (CD45- /CD56+ ) in these samples indicated the need for their thorough immunophenotypic identification, in order to elucidate their possible interference in NBL-MRD assessment. PROCEDURE: RCP observed in BM samples from 14 children recovering from BM aplasia due to intensive chemotherapy for B-ALL were investigated with the following markers: CD81, CD200, CD24, GD2, CD73, CD13, CD90, CD146, CD9, CD117, CD10, CD99, and NG2. BM samples from six newly diagnosed patients with NBL and an NBL cell line were simultaneously investigated as positive controls. RESULTS: The frequency of RCP in B-ALL BM samples was < 1/1 × 104 cells (bulky lysis), and their immunophenotypic profile was indicative of CD56+ mesenchymal stromal cells (MSCs) (CD45- , CD90+ , CD146+ , CD73+ ). Also, RCP expressed CD81 and CD200, simulating NBL cells. The most useful discriminative markers for CD56+ MSCs were CD13 and CD73. An appropriate protocol consisting of two tubes with seven color combinations was further proposed: SYTO-16, GD2 (first tube) or CD73 (second tube)-PE, CD24-ECD, CD13-PC5.5, CD45-PC7, CD81-APC, and CD56-APC700. CONCLUSIONS: RCP that were immunophenotypically similar to NBL were identified as CD56+ MSCs. As these cells might pose an obstacle to accurate NBL disease assessment by FC, especially MRD, an enhanced NBL-FC protocol is proposed for prospective evaluation.

Urine neutrophil gelatinase-associated lipocalin to predict acute kidney injury in preterm neonates. A pilot study.

BACKGROUND: The efficacy of urine neutrophil gelatinase-associated lipocalin (uNGAL) as an early acute kidney injury (AKI) biomarker in preterm neonates was evaluated. METHODS: Thirty-five preterm neonates were prospectively evaluated for serum creatinine (sCre)-documented AKI during the first 14 days of life. Urine samples were collected daily throughout the study period. Of the neonates evaluated, we analyzed 11 who developed AKI (cases) and an equal number of neonates without AKI (controls) matched for gestational and postnatal age (case-control study). uNGAL was measured on the day of AKI occurrence (day 0) and on the 2 days preceding the event (day -1 and day -2, respectively) using an enzyme-linked immunosorbent assay. RESULTS: Cases had significantly higher sCre levels than controls on day 0 (1.21 ± 0.48 vs. 0.83 ± 0.16 mg/dL, p =0.031) but not on days -1 and -2. Similarly, uNGAL levels (ng/mL) were significantly higher in cases than in controls only on day 0 (19.1 ± 3.5 vs. 13.3 ± 7.3, p=0.017) and not on days -1 (18.8 ± 3.4 vs. 16.3 ± 5.9, p=0.118) and -2 (19.3 ± 1.8 vs. 19.4 ± 0.8, p =0.979). The receiver operating characteristic curve analysis showed no significant ability of uNGAL to predict AKI on days -2 and -1. CONCLUSIONS: In this pilot study in preterm neonates, although uNGAL detected sCre-based AKI upon its documentation, it failed to predict its development 1-2 days earlier.

Serum and urine acute kidney injury biomarkers in asphyxiated neonates.

BACKGROUND: We evaluated serum (s) cystatin C (CysC) and neutrophil gelatinase-associated lipocalin (NGAL) and urine (u) CysC, NGAL and kidney injury molecule-1 (KIM-1) as markers of acute kidney injury (AKI) in asphyxiated neonates. METHODS: AKI biomarkers were measured in 13 asphyxiated neonates born at ≥ 36 weeks gestational age (eight with AKI and five without AKI) and 22 controls. AKI was defined as serum creatinine ≥ 1.5 mg/dl for >24 h or rising values >0.3 mg/dl from day of life (DOL) 1. Biomarkers were measured on DOL 1, 3, and 10. RESULTS: Asphyxiated neonates had significantly higher sCysC on DOL 1 as well as sNGAL and uCysC and uNGAL (standardized to urine creatinine and absolute values) than controls at all time points. Compared to controls, significantly higher sNGAL, uCysC, and uNGAL values were observed in the asphyxia-AKI and asphyxia-no AKI subgroups. Regarding uKIM-1, only the absolute values were significantly higher in asphyxiated neonates (DOL 10). sNGAL, uCyst, and uNGAL had a significant diagnostic performance as predictors AKI on DOL 1. CONCLUSIONS: sNGAL, uCysC, and uNGAL are sensitive, early AKI biomarkers, increasing significantly in asphyxiated neonates even in those not fulfilling AKI criteria. Their measurement on DOL 1 is predictive of post-asphyxia-AKI.

Ghrelin levels in patients with juvenile idiopathic arthritis: relation to anti-tumor necrosis factor treatment and disease activity.

Studies in adults with rheumatoid arthritis reported low serum ghrelin that increased following anti-tumor necrosis factor (TNF) infusion. Data on juvenile idiopathic arthritis (JIA) are lacking. The aim of this pilot study was to explore serum ghrelin levels in patients with JIA and the possible association with anti-TNF treatment, disease activity, and nutritional status. Fifty-two patients with JIA (14/52 on anti-TNF treatment) were studied. Juvenile idiopathic arthritis was inactive in 3 of 14 anti-TNF-treated patients and in 11 of 38 non-anti-TNF-treated patients. The nutritional status, energy intake/requirements, appetite, and fasting serum ghrelin levels were assessed. Ghrelin control values were obtained from 50 individuals with minor illness matched for age, sex, and body mass index. Ghrelin levels in patients with JIA were significantly lower than in controls (P < .001, confidence interval [CI] = -101 to -331). Analysis according to anti-TNF treatment and disease activity showed that ghrelin levels were comparable to control values only in 3 patients with anti-TNF-induced remission. Ghrelin in non-anti-TNF-treated patients in remission was low. Multiple regression analysis showed that disease activity (P = .002, CI = -84.16 to -20.01) and anti-TNF treatment (P = .003, CI = -82.51 to -18.33) were significant independent predictors of ghrelin after adjusting for other potential confounders. Ghrelin did not correlate with nutritional status, energy balance, and appetite. Serum ghrelin is low in patients with JIA and is restored to values similar to those in controls following anti-TNF-induced remission. Our study provides evidence that TNF blockade is independently associated with serum ghrelin, which possibly contributes to anti-TNF-induced remission. These preliminary results could form the basis for future research.

Thrombomodulin and von Willebrand factor: relation to endothelial dysfunction and disease outcome in children with acute lymphoblastic leukemia.

The severe endothelial dysfunction in children with acute lymphoblastic leukemia (ALL) can result from the disease itself, from treatment, or from other conditions (e.g. sepsis). The aim of this study was to determine the levels of markers of endothelial activation in children with ALL and to assess their potential prognostic value. Fifty-two children with ALL, 19 children with ALL 1-10 years after the completion of therapy, and 28 healthy children were studied. In children with ALL, there was a significant increase in thrombomodulin (TM) and von Willebrand factor (vWF) levels during the acute phase of the disease and during treatment. Children with an unfavorable outcome had higher levels of TM. In conclusion, severe endothelial dysfunction is present during the acute phase of ALL and during treatment and appears to result from the disease itself. Serum TM and vWF levels might represent additional, but not independent, prognostic markers in childhood ALL.

Interactions between human phagocytes and Candida albicans biofilms alone and in combination with antifungal agents.

BACKGROUND: Biofilm formation is an important component of vascular catheter infections caused by Candida albicans. Little is known about the interactions between human phagocytes, antifungal agents, and Candida biofilms. METHODS: The interactions between C. albicans biofilms and human phagocytes alone and in combination with anidulafungin or voriconazole were investigated and compared with their corresponding planktonic counterparts by means of an in vitro biofilm model with clinical intravascular and green fluorescent protein (GFP)-expressing strains. Phagocyte-mediated and antifungal agent-mediated damages were determined by 2,3-bis[ 2- methoxy-4-nitro-5-sulfophenyl]2H-tetrazolium-5-carboxanilide assay, and structural effects were visualized by confocal microscopy. Oxidative burst was evaluated by flow cytometric measurement of dihydrorhodamine 123 oxidation, and cytokine release was measured by enzyme-linked immunosorbent assay. RESULTS: Phagocytes alone and in combination with antifungal agents induced less damage against biofilms compared with planktonic cells. However, additive effects occurred between phagocytes and anidulafungin against Candida biofilms. Confocal microscopy demonstrated the absence of phagocytosis within biofilms but marked destruction caused by anidulafungin and phagocytes. Anidulafungin but not voriconazole elicited tumor necrosis factor alpha release from phagocytes compared with that from untreated biofilms. CONCLUSIONS: C. albicans within biofilms are more resistant to phagocytic host defenses but are susceptible to additive effects between phagocytes and an echinocandin.

Diagnostic utility of elevated serum soluble triggering receptor expressed on myeloid cells (sTREM)-1 in infected neonates.

OBJECTIVE: To assess the value of serum levels of soluble triggering receptor expressed on myeloid cells-1 (sTREM-1) for early diagnosis of late-onset sepsis (LOS) in neonates, compared with interleukin-6 (IL-6). DESIGN AND SETTING: Prospective, observational study in a single, level III neonatal intensive care unit of a university hospital. PATIENTS: Fifty-two preterm and term neonates evaluated for suspected LOS were studied. Neonates were classified into two groups: infected [confirmed sepsis (n = 22) and possible sepsis (n = 9)] and noninfected neonates (n = 21). MEASUREMENTS AND RESULTS: Serum sTREM-1 and IL-6 were measured (enzyme-linked immunosorbent assays) when signs suggestive of sepsis emerged. Infected neonates had significantly higher sTREM-1 (p = 0.004) and IL-6 (p < 0.0001) than noninfected neonates. Receiver operating characteristic (ROC) curve analysis resulted in significant areas under the curve (AUC) for both sTREM-1 (AUC = 0.733, p = 0.005) and IL-6 (AUC = 0.892, p = 0.001) for identification of infected neonates, with the difference between the two AUC not being significant. Further analysis documented acceptable diagnostic performance of sTREM-1 and IL-6, which was not improved, however, when the two markers were combined. CONCLUSIONS: Serum sTREM-1 increases in infected neonates. Diagnostic accuracy of sTREM-1 either alone or in combination with IL-6 is not better than that of IL-6.

In vivo effect of rhGM-CSF And rhG-CSF on monocyte HLA-DR expression of septic neonates.

OBJECTIVE: To investigate the effect of rhGM-CSF and rhG-CSF on the monocyte HLA-DR expression of septic neonates. SUBJECTS: 60 septic neonates and 41 healthy ones. Septic neonates were randomly assigned into three treatment groups, the GM-CSF group [n=20, rhGM-CSF 5 mcg/kg/d for 4 days, intravenously over 2h (IV)], the G-CSF group (n=20, rhG-CSF 10 mcg/kg/d for 4 days, IV) and the placebo group (n=20, normal saline for 4 days, IV). MEASUREMENTS: Serial (days 0,1, 3 and 5 after the onset of sepsis) measurements of the percentage of HLA-DR positive monocytes (%HLA-DR+ monocytes) and mean fluorescence intensity (MFI) by flow-cytometry as well as the absolute monocyte counts (AMC). MAIN RESULTS: On day 0, the HLA-DR expression of the septic neonates (%HLA-DR+ monocytes: 38%+/-1.8% (mean+/-SEM) and MFI: 73+/-3.4) was significantly lower than the healthy control values (%HLA-DR+ monocytes: 68%+/-2% and MFI: 123+/-4.6) (P<0.0001, for both parameters). On follow up (days 1, 3 and 5), a significant increase of HLA-DR expression was observed in all the groups of septic neonates. Healthy control values of %HLA-DR+ monocytes were reached by day 1 in the GM-CSF group and by day 3 in the G-CSF and placebo groups. Healthy control values of MFI were reached by day 3 in all groups of septic neonates. The AMC showed a significant increase in the GM-CSF group (during the whole follow up period) and in the G-CSF group (for the first 3 days of follow up). CONCLUSIONS: The monocyte HLA-DR expression is depressed on the onset of neonatal sepsis and is progressively restored during the following days. Treatment with rhGM-CSF results in an earlier increase of the number of monocytes expressing the HLA-DR.