Urinary Biomarkers of Inflammation and Oxidative Stress Are Elevated in Obese Children and Correlate with a Marker of Endothelial Dysfunction

Obesity is a state of chronic low-level inflammation closely associated with oxidative stress. Childhood obesity is associated with endothelial dysfunction, inflammation, and oxidative stress markers individually. This study was aimed at determining the association between the biomarkers of inflammation, oxidative stress, and endothelial dysfunction in urine samples of healthy, overweight, and obese children. Eighty-eight elementary school children aged between 6 and 10 years participated in this study. Anthropometric measurements were measured using WHO recommendations. The biomarkers of low-grade inflammation such as C-reactive protein (CRP), interleukin-6 (IL-6), and α-1-acid glycoprotein (AGP); oxidative stress markers such as 8-isoprostane and 8-hydroxy-2'-deoxyguanosine (8-OHdG); and endothelin-1 (ET-1) were analyzed in urine samples. The area under the curve (AUC) by the receiver operating characteristics (ROC) was analyzed to identify the best urinary biomarker in childhood obesity. Linear regression and Pearson correlation were analyzed to determine the association between the parameters. The obese participants have significantly increased levels of CRP, AGP, IL-6, and 8-isoprostane compared to normal-weight participants. The overweight participants had significantly increased levels of ET-1 and 8-OHdG but not the obese group compared to the NW group. The AUC for urinary CRP (AUC: 0.847, 95% CI: 0.765-0.930; p < 0.0001) and 8-isoprostane (AUC: 0.857, 95% CI: 0.783-0.932; p < 0.0001) showed a greater area under ROC curves compared to other inflammatory and oxidative markers. The urinary CRP and 8-isoprostane significantly correlated with the obesity measures (body mass index, waist circumference, and waist-to- height ratio) and ET-1, inflammatory, and oxidative markers. The increased urinary inflammatory markers and 8-isoprostane can serve as a noninvasive benchmark for early detection of the risk of developing cardiovascular disease.

Identification of inflammatory markers suitable for non-invasive, repeated measurement studies in biobehavioral research: A feasibility study

Introduction

Studying the role of the immune system in the interaction between mental and physical health is challenging. To study individuals with an intensive, longitudinal study design that requires repetitive sampling in their daily life, non-invasive sampling techniques are a necessity. Urine can be collected in a non-invasive way, but this may be demanding for participants and little is known about fluctuation of inflammatory markers in urine over time. The aim of this study was to investigate the feasibility of non-invasive sampling, and to explore intra-individual differences in inflammatory markers in urine.

Materials & methods

Ten healthy individuals collected 24-hour urine for 63 consecutive days. In a pilot analysis, 39 inflammatory markers were examined for detectability in urine, stability over time and under storage conditions, and daily fluctuations. Multiplex analyses were used to quantify levels of eight selected markers: C-reactive protein (CRP), Fractalkine, Interleukin-1 receptor-antagonist (IL-1RA), interferon-α (IFNα), interferon-γ (IFNγ), Interferon gamma-induced protein 10 (IP10), Macrophage inflammatory protein-1β (MIP-1β), and Vascular Endothelial Growth Factor (VEGF). Cross-correlations were calculated between the overnight and 24-hour samples were calculated, to examine whether 24-hour urine could be replaced by the overnight portion for better feasibility. We examined intra- and interindividual differences in the levels of inflammatory markers in urine and the fluctuations thereof.

Results

This study showed that levels of selected inflammatory markers can be detected in urine. Cross-correlation analyses showed that correlations between levels of inflammatory markers in the night portion and the 24-hour urine sample varied widely between individuals. In addition, analyses of time series revealed striking inter- and intra-individual variation in levels of inflammatory markers and their fluctuations.

Conclusion

We show that the assessment of urinary inflammatory markers is feasible in an intensive day-to-day study in healthy individuals. However, 24-hour urine cannot be replaced by an overnight portion to alleviate the protocol burden. Levels of inflammatory markers show substantial variation between and within persons.

Urinary excretion of pentraxin-3 correlates with the presence of renal scar following acute pyelonephritis in children

PURPOSE

Acute pyelonephritis is associated with considerable morbidity and potential for renal scarring. Pentraxin3 (PTX3) is a recently discovered mediator of inflammation. The objective of this study was to investigate the changes in serum and urine PTX3 levels in children who had a history of pyelonephritis and were diagnosed with renal parenchymal scar (RPS) and/or vesicoureteral reflux (VUR).

METHODS

The study included 88 children (31 males, 57 females) aged between 3 months and 18 years. The children included in the study were divided into four groups: VUR with RPS (Group 1), RPS without VUR (Group 2), VUR without RPS (Group 3), and healthy children without a history of hydronephrosis or UTI history (Group 4). After the initial evaluation, the participants were further divided into two more groups and re-evaluated: Children with RPS (Group 1 + 2), children without RPS (Group 3 + 4), children with VUR (Group 1 + 3), and children without VUR (Group 2 + 4).

RESULTS

We found that urine pentraxin 3 (uPTX3) and uPTX3/Creatinine levels were significantly higher in the groups with renal scar with or without VUR than the ones without RPS [mean uPTX3, 3.5 pg/ml (min-max 0.0022-12.3668) vs. 2.2 pg/ml (min-max 0.0022-18.5868) and uPTX3/creatinine, 10.5 pg/mg (min-max 0.0035-51.1) vs. 5.8 pg/mg (min-max 0.0004-78.7), p < 0.01]. uPTX3 levels were not different among the groups with and without VUR. In addition, serum PTX3 levels were not different among the groups.

CONCLUSIONS

We showed that urinary PTX3 increased only in patients with scarred kidneys. These results might be helpful to predict RPS due to past pyelonephritis.

Gold/silver/gold trilayer films on nanostructured polycarbonate substrates for direct and label-free nanoplasmonic biosensing

Ultrasmooth gold/silver/gold trilayer nanostructured plasmonic sensors were obtained using commercial Blu-ray optical discs as nanoslits-based flexible polymer substrates. A thin gold film was used as an adhesion and nucleation layer to improve the chemical stability and reduce the surface roughness of the overlying silver film, without increasing ohmic plasmon losses. The structures were physically and optically characterized and compared with nanostructures of single gold layer. Ultrasmooth and chemically stable trilayer nanostructures with a surface roughness <0.5 nm were obtained following a simple and reproducible fabrication process. They showed a figure of merit (FOM) value up to 69.2 RIU^-1 which is significantly higher (more than 95%) than the gold monolayer counterpart. Their potential for biosensing was demonstrated by employing the trilayer sensor for the direct and refractometric (label-free) detection of C-reactive protein (CRP) biomarker in undiluted urine achieving a Limit of Detection (LOD) in the pM order.

A Smartphone-Based Colorimetric Reader for Human C-Reactive Protein Immunoassay

A smartphone-based colorimetric reader (SBCR), comprising a Samsung Galaxy SIII mini, a gadget (iPAD mini, iPAD4, or iPhone 5s) and a custom-made dark hood and base holder assembly, is used for human C-reactive protein (CRP) immunoassay. A 96-well microtiter plate (MTP) is positioned on the gadget's screensaver to provide white light-based bottom illumination only in the specific regions corresponding to the well's bottom. The images captured by the smartphone's back camera are analyzed by a novel image processing algorithm. Based on one-step kinetics-based human C-reactive protein immunoassay (IA), SBCR is evaluated and compared with a commercial MTP reader (MTPR). For analysis of CRP spiked in diluted human whole blood and plasma as well as CRP in clinical plasma samples, SBCR exhibits the same precision, dynamic range, detection limit, and sensitivity as MTPR for the developed IA (DIA). Considering its compactness, low cost, advanced features and a remarkable computing power, SBCR is an ideal point-of-care (POC) colorimetric detection device for the next-generation of cost-effective POC testing (POCT).

Compartmentalization of acute phase reactants Interleukin-6, C-Reactive Protein and Procalcitonin as biomarkers of intra-amniotic infection and chorioamnionitis

BACKGROUND

The arsenal of maternal and amniotic fluid (AF) immune response to local or systemic infection includes among others the acute-phase reactants IL-6, C-Reactive Protein (CRP) and Procalcitonin (PCT). If these molecules can be used as non-invasive biomarkers of intra-amniotic infection (IAI) in the subclinical phase of the disease remains incompletely known.

METHODS

We used time-matched maternal serum, urine and AF from 100 pregnant women who had an amniocentesis to rule out IAI in the setting of preterm labor, PPROM or systemic inflammatory response (SIR: pyelonephritis, appendicitis, pneumonia) to infection. Cord blood was analyzed in a subgroup of cases. We used sensitive immunoassays to quantify the levels of inflammatory markers in the maternal blood, urine and AF compartment. Microbiological testing and placental pathology was used to establish infection and histological chorioamnionitis.

RESULTS

PCT was not a useful biomarker of IAI in any of the studied compartments. Maternal blood IL-6 and CRP levels were elevated in women with subclinical IAI. Compared to clinically manifest chorioamnionitis group, women with SIR have higher maternal blood IL-6 levels rendering some marginal diagnostic benefit for this condition. Urine was not a useful biological sample for assessment of IAI using either of these three inflammatory biomarkers.

CONCLUSIONS

In women with subclinical IAI, the large overlapping confidence intervals and different cut-offs for the maternal blood levels of IL-6, CRP and PCT likely make interpretation of their absolute values difficult for clinical decision-making.

Urinary C reactive protein levels in dogs with leishmaniasis at different stages of renal damage

The objectives of the study were to validate a time-resolved immunofluorometric assay for C reactive protein (CRP) quantification in urine of dogs and to investigate the influence that the presence of proteinuria and azotemia could have on serum and urinary CRP (uCRP) values in dogs with leishmaniasis. Samples obtained from dogs naturally infected with Leishmania infantum were classified into four groups on the basis of the results of urinary protein/creatinine ratio and serum creatinine (sCr). In addition, 7 dogs were monitored at initial diagnosis and after a follow up visit. The assay showed good analytical performance based on precision, accuracy and limit of detection results. Results of the study suggested that CRP is present in urine of dogs with leishmaniasis and renal damage since uCRP/creatinine ratio was significantly increased in dogs with proteinuria, being the highest values observed in dogs with proteinuria and elevated sCr, and that the measurement of uCRP could be a tool to detect and evaluate the possible kidney damage associated with this disease.

[Proinflammatory cytokines and C-reactive protein in urine: prospects for diagnosis in patients with chronic pyelonephritis]

The study involved 85 patients with chronic pyelonephritis in age from 26 to 62 years. All patients determined C-reactive protein (CRP), interleukin 6 and tumor necrosis factor-alpha in the blood and urine by standard techniques. With the simultaneous study of CRP in the blood and urine of patients with chronic pyelonephritis detected high levels of this biomarker in the urine, which is several times higher than its indicators levels in blood. When studying the levels of proinflammatory cytokines, which are the main inducers excretion of CRP, we found that the increase in their concentration in urine was more pronounced than in the blood, which confirms the opinion that CRP can be synthesized in inflammation focus by lymphocytes, macrophages and endothelial. Studying the levels of cytokines and C-reactive protein in the urine can be used to assess the severity of inflammatory changes in the kidney and to monitor the effectiveness of anti-inflammatory therapy.

[Modern principles of diagnosis and prediction of course of chronic obstructive pyelonephritis in children]

An assessment of changes in the levels of cytokines, cell adhesion molecules, acute phase proteins in serum, urine and biopsy using ELISA was performed. The evaluation was performed in 167 patients with various congenital urinary tract obstructions in the perioperative period. It is shown that serum C-reactive protein and IL-6, IL-8 urine levels have high diagnostic significance for determining the severity of inflammation in the urinary tract in the development of chronic obstructive pyelonephritis at different levels of obstruction. The calculation of the proposed index of inflammation activity based on IL-8 and IL-10 urine levels in children in the dynamics allows to estimate the phase of inflammation and efficacy of the treatment.

Homeostasis model assessment of insulin resistance for evaluating insulin sensitivity in patients with type 2 diabetes on insulin therapy

Homeostasis model assessment of insulin resistance (HOMA-IR) is a simple and useful method for evaluating insulin sensitivity. But it is difficult to apply to type2 diabetes patients treated with insulin. We have devised a method for measuring HOMA-IR and investigated the validity of HOMA-IR for evaluating insulin sensitivity in patients with type 2 diabetes on insulin therapy. In the first arm of the study, 19 poorly controlled diabetic subjects were treated with insulin and underwent euglycemic clamp study. Then the relationship between insulin resistance index assessed by the clamp test (clamp-IR) and HOMA-IR was investigated in these subjects. Log transformed HOMA-IR correlated with log transformed M/I values derived from the standard euglycemic clamp (r=-0.753, p=0.002). In the second arm of the study, we investigated the relationship between HOMA-IR and various clinical parameters in 156 patients with poorly controlled diabetes after glycemic control. Log transformed HOMA-IR correlated negatively with age (r=-0.292, p=0.0002), HDL-C (r=-0.342, p<0.0001), log transformed serum adiponectin (r=-0.309, p=0.0006) and log transformed KITT (r=-0.264, p=0.0009), and positively with body mass index (r=0.499, p<0.0001), waist circumstance (r=0.461, p<0.0001), visceral fat area (r=0.401, p<0.0001), diastolic blood pressure (r=0.223, p=0.0054), log transformed triglyceride (r=0.497, p<0.0001), urinary CPR (r=0.216, p=0.0099), ΔCPR of glucagon stimulation test (r=0.496, p<0.0001) and log transformed insulinogenic index (r=0.325, p=0.0002). These results suggest that HOMA-IR is a useful test for the evaluation of insulin sensitivity even in patients with type 2 diabetes treated with insulin.

[Is there an association of uric acid level with preclinical target organ damage in moderate- and high-risk hypertensive patients?]

AIM

To assess an association of uric acid level with preclinical target organ damage in patients with hypertensive disease (HD).

SUBJECTS AND METHODS

The trial enrolled 100 patients (63 men and 37 women) with Stage I-II HD at moderate and high risk for cardiovascular events (CVEs). The mean age of the patients was 44.9 +/- 1.3 years. Their medical history showed that the duration of hypertension averaged 4.4 +/- 0.3 years. The average daily level of systolic blood pressure (BP) was 138.1 +/- 1.4 mm Hg and that of diastolic BP was 84.3 +/- 1.1 mm Hg.

RESULTS

The entire patient group showed a positive correlation between C-reactive protein (CRP) and serum uric acid (SUA) (r = 0.27; p < 0.01), suggesting that the nonspecific inflammatory processes were associated with uric acid levels in patients with HD. An intragroup analysis also revealed a relationship between CRP and SUA levels in the hypertensive patients at high risk for CVEs (r = 0.43; p = 0.01); this relationship was not found in those at their low risk. The hypertensive patients were ascertained to have elevated CRP levels and microalbuminuria, hyperuricosuria, and glomerular hyperfiltration when they had a SUA level >319 micromol/l.

CONCLUSION

It can be assumed that the SUA level >319 micromol/l triggers the activation of nonspecific inflammatory processes, which in turn affects renal microvessels.

Increased urine and serum nerve growth factor levels in interstitial cystitis suggest chronic inflammation is involved in the pathogenesis of disease

Objective

Interstitial cystitis/bladder pain syndrome (IC/BPS) is considered a bladder disorder due to localized chronic inflammation. This study investigated the nerve growth factor (NGF) levels in serum and urine in patients with IC/BPS.

Materials and Methods

Thirty patients with IC/BPS and 28 normal subjects without lower urinary tract symptoms were recruited from an outpatient clinic. IC/BPS was diagnosed by frequency, bladder pain, and the presence of glomerulations during cystoscopic hydrodistention. Serum and urine were collected before any treatment was given. Serum NGF and urinary NGF/Cr levels were compared between IC/BPS and the controls.

Results

Urinary NGF levels were significantly higher in patients with IC/PBS (26.3±11.2 pg/ml) than in controls (1.40±0.63 pg) (p = 0.014). After normalization, the urinary NGF/Cr levels were significantly greater in IC/BPS (0.69±0.38 pg/mg) than controls (0.20±0.01, p = 0.011). Relative to the levels in control subjects (1.90±0.38 pg/mL), the mean serum NGF levels were higher in patients IC/BPS patients (3.48±0.55 pg/mL) (p = 0.015). No significant correlation was found between the serum and urinary NGF levels in IC/BPS patients. However, the clinical characteristics and medical co-morbidities did not show significant difference between IC/BPS patients with a higher and lower serum NGF level.

Conclusions

Increased urinary NGF levels in IC/BPS patients suggest that chronic inflammation is involved in this bladder disorder. Increased circulating serum NGF levels were noted in over half of patients with IC/BPS, however, the urinary and serum NGF were not inter-correlated and elevated serum NGF did not relate with clinical features.

Alterations in L-arginine and inflammatory markers in type 2 diabetic patients with and without microalbuminuria

Low-grade inflammation is closely involved in the pathogenesis of type 2 diabetes and associated micro- and macrovascular complications. The nitric oxide (NO) precursor L-arginine, is relevant to diverse pathological conditions including type 2 diabetes and its complications. High sensitive-CRP (hs-CRP), neopterin and arginine levels were measured in 46 normoalbuminuric, 45 microalbuminuric type 2 diabetics and in 32 healthy controls in order to assess the relationship between markers of inflammation and L: -arginine. Hs-CRP concentrations were higher in microalbuminuric diabetic patients compared to normoalbuminuric patients and controls. Diabetics had higher serum and urine neopterin levels than controls. Urine neopterin and L-arginine levels differed significantly among diabetic patients with and without microalbuminuria. There were significant positive correlations between hs-CRP and BMI in healthy controls and diabetics with and without microalbuminuria. In microalbuminuric diabetics, hs-CRP correlated with microalbuminuria (MAU). Significant predictors for the development of microalbuminuria were higher postprandial glucose levels, lower creatinine clearance and lower serum L-arginine levels. Assessment of early markers of inflammation and endothelial function, such as neopterin and NO precursor L-arginine, may help to predict incipient nephropathy more accurately in type 2 diabetic patients.

Urinary proteins in children with urinary tract infection

The aim of this study was to test our hypothesis that the urinary excretion of C-reactive protein (CRP), alpha 1-microglobulin (A1M), retinol-binding protein (RBP) and Clara cell protein (CC16) is increased in children with urinary tract infection (UTI) and relates to renal damage as measured by acute dimercaptosuccinic acid (DMSA) scintigraphy. Fifty-two children <2 years of age with UTI were enrolled in the study, 44 of whom were febrile. The control group consisted of 23 patients with non-UTI infection and elevated serum CRP (s-CRP) levels. Thirty-six patients had abnormal DMSA uptake, classified as mild, moderate or severe damage (DMSA class 1, 2, 3, respectively). There was a significant association between DMSA class and the excretion of urinary RBP (u-RBP) and u-CC16. There was also a significant difference in u-CRP levels between children with UTI and control children with non-UTI infections, although u-CRP excretion was not significantly correlated to DMSA class. In conclusion, the urinary excretion of the low-molecular-weight proteins RBP and CC16 showed a strong association with uptake defects on renal DMSA scans. The urinary level of CRP seems to distinguish between children with UTI and other febrile conditions. A combination of these biomarkers may be useful in the clinical assessment of children with UTI.

Acute toxicity pilot evaluation of proliferol in rats and swine

Proliferol is an investigational new drug containing lidocaine hydrochloride 0.25%, dextrose 12.5%, glycerin 12.5%, and phenol 1.0% in aqueous solution. Despite extensive previous experience with similar drug solutions administered in humans by intraligamentous injection for chronic musculoskeletal conditions for over 50 years, animal toxicity data are unavailable. A pilot study was conducted to assess acute toxic effects prior to undertaking further assessment of this drug. Test animals were four Sprague-Dawley rats and four Yucatan mini-swine. Rats received injections into lumbar paraspinal muscles, whereas swine received injections into lumbosacral ligaments in an attempt to mirror the method of administration in humans. Two doses were studied equivalent to 1x and 5x the typical human dose. Outcomes measured at 24 h and 14 days included clinical observations, clinical chemistry, hematology, urinalysis, local tolerance, and major organ histopathology. In rats and swine, results from clinical chemistry, hematology, and urinalysis were indicative of acute local inflammation. At the high dose, marked (rats) and moderate (swine) short-term above-normal levels in certain liver enzymes were noted. In rats and swine, local tolerance results were indicative of acute local inflammatory changes in the skin, subcutis, and muscle around the injection sites. In rats and swine, major organ histopathology results did not reveal lesions attributable to the drug and clinical observations were within normal limits. In swine, fibroplasia was noted in deeper muscle tissues after 14 days. Injections of Proliferol in lumbar paraspinal muscles in rats and lumbosacral ligaments in swine elicited a modest acute local inflammatory response with no other indications of local or systemic toxicity.

Reduction in urea distribution volume over time in clinically stable dialysis patients

We have previously shown that, assuming urea distribution volume (V) remains constant for 1 month, ionic dialysance (ID) allows the dialysis dose to be calculated without the need for blood sampling. The aim of this multicenter study was to verify whether the assumption of a constant V can be extended to 1 year. In clinically stable patients receiving thrice-weekly hemodialysis at 13 dialysis centers, V and Kt/V were assessed during three dialysis sessions at baseline and 1 year later using ID as dialyzer urea clearance and the single-pool urea kinetic model. Baseline albumin, hemoglobin, and C reactive protein were prespecified covariates for predicting the change in V over time. Of the 52 enrolled patients, 40 (25 males; age 63.0+/-13.5 years) completed the study. Baseline end-dialysis body weight (62.4+/-13.7 kg) showed a non-significant 1% reduction during follow-up (-0.6+/-2.8 kg; P=0.175), whereas V significantly decreased from 29.0+/-6.8 to 27.4+/-6.0 l (-1.6+/-3.0 l or 4.5%; P=0.002). The reduction in V was greater when baseline albumin was lower (P=0.001) and baseline V was higher (P=0.005). The single-pool K(t)/V calculated using baseline V underestimated the actual value by 0.07+/-0.16 (P=0.008). The slight underestimate of Kt/V during follow-up suggests that annual V evaluations may be sufficient for dialysis dose quantification as the only risk is underestimating the actually delivered dialysis dose. However, the relationship between baseline albumin and the reduction in V over time may have nutritional value, and suggests more frequent V evaluations.

Heterogeneity of early-onset and ketosis-resistant diabetes in Korean subjects--is it possible to determine cut-off age of early-onset type 2 diabetes?

OBJECTIVE

To investigate the heterogeneity of early-onset and ketosis-resistant diabetes and to define a not-arbitrary cut-off age for early-onset diabetes based on its clinical and metabolic characteristics, and diabetes complications.

METHODS

We classified 1015 early-onset diabetes subjects aged 21-40 into four groups (group I, age at diagnosis 21-25 years; group II, 26-30; group III, 31-35; group IV, 36-40). Familial and diabetic history, statue of insulin secretion, metabolic parameters, and diabetes complications were analyzed.

RESULTS

No significant difference in family history or the rate of diabetic complication was found in the four groups. Subjects with a 21 to a 25-year-old diabetes onset had the lowest serum C-peptide levels, with 50% of the cumulative 24-h urine C-peptide levels of the other three groups (p<0.0001). This group also had the lowest prevalence of hyperlipidemia and arterial hypertension (p<0.01 and <0.0001, respectively). Group III was found to have a higher prevalence of insulin insufficiency and hypertension than group IV.

CONCLUSION

Our data based on insulin secretory function and metabolic factors might suggest that a cut-off age of 26 years might be warranted in Korean patients. Korean early-onset type 2 diabetes patients tend to be non-obese and insulin secretory dysfunction.

[Urinary concentration of proinflammatory cytokines with regard to infected urinary tract region]

Uropathogenic bacteria stimulate epithelial cells of interstitial tissue and macrophages to secrete proinflammatory cytokines: interleukin I (IL-1beta), interleukin 6 (IL-6) and interleukin 8 (IL-8). The aim of the study was to check: 1) if the concentration of proinflammatory cytokines (IL-1beta, IL-6, IL-8) differs in dependence on region and clinical picture of urinary tract infection, 2) what is the influence of antibacterial treatment on their concentration.

MATERIAL

We examined 67 children, aged 1-15 years, who were divided into 3 groups: 27 children with acute pyelonephritis (AP), caused by E. coli (group I), in whom the examination was carried out twice: A - before treatment, B - after 14 days of antibacterial treatment, 10 children with chronic urinary tract infection (UTI) associated with neurogenic bladder (group II) and 30 healthy children (group K).

METHOD

Urinary concentration of examined cytokines was assessed using ELISA immunoenzymatic method and was expressed in pg/mg creatinine. Results showed that in group I before treatment the urinary concentration of examined cytokines was increased (p<0.05). After antibacterial treatment concentration of IL-1beta was normal and concentration of IL-6 and IL-8 decreased but was still higher than in control group (p<0.05). In group II before treatment the increase in concentration of IL-1beta and IL-8 was not so high (p<0.05) and the urinary concentration of IL-6 was normal (p>0.05). In examination A in children from group I and II a positive correlation between examined cytokines and C reactive protein was shown. We have also found a positive correlation between urinary concentration of IL-1beta a IL-8.

CONCLUSIONS

1. Urinary concentration of examined proinflammatory cytokines is different in children with AP and UTI associated with neurogenic bladder and correlates with concentration of C-reactive protein. 2. In most of children with AP after 14-days of antibacterial treatment the urinary concentration of proinflammatory cytokines has been increased.

Evidence of fetal C-reactive protein urinary excretion in early gestation

BACKGROUND

C-reactive protein has been measured in amniotic fluid in the second and third trimesters of gestation, and its elevated concentration has been found to be associated with adverse pregnancy outcome. It remains unexplained whether amniotic fluid C-reactive protein is of fetal origin.

CASE

We report the measurement of C-reactive protein in fetal urine obtained by transabdominal vescicocentesis in a fetus at 15 weeks' gestation affected by obstructive uropathy. Using an enzyme-linked immunosorbent assay, C-reactive protein was detected at a concentration of 234 ng/mL.

CONCLUSION

The fetal kidneys excrete C-reactive protein as early as 15 weeks' gestation.

Structure of C-reactive protein excreted in urine during acute rejection episodes

During acute rejection of renal allografts C-reactive protein is excreted in urine in a monomeric form. We developed an immunochemical method for detecting monomeric C-reactive protein in human physiological fluids, which is based on latex agglutination.

Clinical utility of a rapid test for uristatin

OBJECTIVES

Uristatin is a trypsin inhibitor present in urine that is increased in most patients with bacterial or viral infections and in many with inflammatory disorders. We included the assay of uristatin as part of a screening program carried out by pediatricians on 4207 Japanese schoolchildren to judge the ability of uristatin to identify those with an infection and (or) inflammation of any cause. We used urine dipsticks for the assay of uristatin, creatinine, albumin, blood, leukocyte esterase, and protein. We also performed quantitative assays for uristatin and creatinine. Another aim was to estimate the reference range for uristatin in schoolchildren, ages 5 to 14 yr.

METHODS

We prepared dipstick pads that were impregnated with a chromogenic substrate for trypsin and measured the uristatin-caused inhibition of trypsin in urine. We measured creatinine so that the ratio of uristatin to creatinine could be calculated to correct for urine concentration.

RESULTS

We obtained quantitative uristatin and creatinine results for 4207 children. Of these, 177 had an abnormal urine dipstick for albumin or blood or protein or leukocyte esterase or a combination of these. We used data from 3622 children to establish the reference range for the uristatin dipsticks. The 3622 were diagnosed by their pediatricians as free from an infection or inflammation of any cause and with normal urine dipstick tests. We recommend an upper reference limit for uristatin by dipstick of < or = 7.5 mg uristatin/g creatinine. The leftover 408 children ( [4207-3622-177] = 408) fell into two groups: 205 with diagnoses of no infection, possible infection, or possible inflammatory disorders. The remaining 203 children were renal disease follow-up cases. The diagnoses were based on a physical examination, microscopic urinalysis plus urine dipstick tests for albumin, blood, creatinine, protein, leukocyte esterase and a complete blood count. In the 205 children, 46 had an abnormal uristatin dipstick test, 39 had an abnormal uristatin by immunoassay, 41 had an abnormal erythrocyte sedimentation rate (ESR), 27 had an abnormal serum C-reactive protein (CRP), and one had an abnormal urine microscopic exam. For the first 938 children in the study, the agreement was 93% of negative dipstick uristatin results and immunoassays. The agreement of positive uristatin dipsticks with immunoassays was 85%. We assumed that the immunoassay results were correct. In the evaluation of 189 children with fever, 62 also had an abnormal uristatin by dipstick.

DISCUSSION

A rapid dipstick test for uristatin read on a reflectance photometer gave values that compared well with a quantitative immunoassay method. The uristatin test is sensitive but not specific for any cause of infection or inflammation. Uristatin is easy to determine and appears to be a better indicator than fever, ESR, or CRP for the diagnosis of an infection or inflammation.

Usefulness of procalcitonin and C-reactive protein rapid tests for the management of children with urinary tract infection

BACKGROUND

Urinary tract infection (UTI) is a common problem in children. Because clinical findings and commonly used blood indices are nonspecific, the distinction between lower and upper urinary tract infection cannot be made easily in this population. However, this distinction is important because renal infection can induce parenchymal scarring. The objective of this study was to determine the accuracy of procalcitonin (PCT) compared with C-reactive protein (CRP) rapid tests to predict renal involvement in children with febrile UTI.

METHODS

PCT and CRP were measured in the blood of children admitted to the emergency room with fever, signs and symptoms of urinary tract infection and/or a positive urine dipstick analysis. Renal parenchymal involvement was assessed by a 99mTc-labeled dimercaptosuccinic acid renal scan in the acute phase of infection in all children. Sensitivity, specificity and likelihood ratios were determined for both tests.

RESULTS

Fifty-four children with a proven urinary tract infection were enrolled: 63% had renal involvement; and 37% had infection restricted to the lower urinary tract. No difference was found for age, sex and total white blood cell count between the groups. The calculated likelihood ratios of procalcitonin and C-reactive protein rapid tests were between 3.8 and 7 and 1.5 and 2.8, respectively. A positive PCT value predicted renal involvement in 87 to 92% of children with febrile UTI, compared with 44 to 83% using CRP values.

CONCLUSIONS

A rapid determination of procalcitonin concentration could be useful for the management of children with febrile UTI in the emergency room.

Effect of pamidronate administration on markers of bone turnover and disease activity in multiple myeloma

AIM

Bisphosphonates are potent inhibitors of osteoclastic activity and are used in the treatment of multiple myeloma (MM) in combination with chemotherapy. The effect of pamidronate on markers of bone resorption [cross-linked N-telopeptides of type I collagen (NTx)], markers of bone formation [serum alkaline phosphatase (BAP) and osteocalcin (OSC)], interleukin-6 (IL-6), beta2-microglobulin, CRP, paraprotein and disease-related pain and skeletal events has been evaluated in 62 newly diagnosed patients with MM.

PATIENTS AND METHODS

The patients were randomly assigned to two groups: the first included 32 patients under chemotherapy and pamidronate (group I) and the second 30 patients on chemotherapy only (group II). Pamidronate was administered at a monthly dose of 90 mg iv, and the above parameters were evaluated at the beginning of this study and after 1, 3, 6, 9, 12 and 14 months of treatment.

RESULTS

The addition of pamidronate to chemotherapy resulted in a significant reduction of NTx, IL-6 and paraprotein from the 3rd month and of beta2-microglobulin, CRP and pain from the 6th month of treatment. No changes of NTx, IL-6, beta2-microglobulin, CRP or skeletal events were observed in patients of group II, while paraprotein was significantly reduced after 6 months of treatment. The differences in NTx, IL-6, paraprotein and beta2-microglobulin were statistically significant between the two groups. Multivariate analysis revealed a significant correlation between changes of NTx, changes of IL-6 in both groups and reduction of pain and paraprotein in group I.

CONCLUSIONS

These results suggest that pamidronate may have a synergistic action with chemotherapy in decreasing osteoclastic activity, in reducing markers of myeloma activity and myeloma related pain and in improving the quality of life in patients with MM.

[Urinary tract infection and biological markers: C-reactive protein, interleukins and procalcitonin]

Serum C reactive protein (CRP) remains a good marker of the severity of urinary tract infections in children, despite false negative results. Serum IL-6 is not a better marker; urinary IL-6 might have a better prognostic value as it is higher in patients with renal lesions due to infection, but low values are found in some cases. Serum procalcitonin levels are correlated with the importance of renal scars at scintigraphy, with less than 10% of false negative results. Further studies are needed to confirm the sensitivity and sensibility of these markers, especially for procalcitonin.

Serum C-reactive protein is rarely lost into urine in patients with secondary amyloidosis and proteinuria

We studied whether the low serum C-reactive protein (S-CRP) level in patients with inflammatory arthritis and proteinuria was due to the loss of CRP into urine. In 19 patients with secondary amyloidosis (14 with rheumatoid arthritis and five with juvenile chronic arthritis), S-CRP was measured with both immunoturbidimetric and radioimmunoassays. The concentration of urinary CRP was measured with a double-antibody radioimmunoassay. One patient with the most extensive proteinuria (12 g/24 h) excreted CRP at 14 mg/24 h, while in 18 of 19 patients only negligible, if any, amounts of CRP were found in 24-h urine samples. Proteinuria of < 8 g/24 h did not reduce the S-CRP level. Proteinuria exceeding this level may result in increased excretion of CRP into urine and consequently may result in a reduced S-CRP level.

[Predictive value of serum ferritin in the prognosis of acute cerebrovascular accident]

INTRODUCTION

Recent studies show that a raised level of serum ferritin indicates a poor prognosis in CVA patients, as do the well-known hyperglycemia, dyslipemia and arterial hypertension. The evolution and prognosis of acute cerebrovascular accidents are determined by a series of factors, some of which can be modified. This leads to a search for factors which can be modified and therefore influence the course of the illness.

OBJECTIVE

To determine the ferritin levels and other parameters during the course of the illness of patients with serious cerebral vascular pathology and evaluate their effect on prognosis.

MATERIAL AND METHODS

A prospective study was carried out on patients diagnosed as having CVA, admitted to the Neurology Department of the Miguel Servet Hospital (Zaragoza) during 1994, and who were in neurological coma (Glasgow scale less than 7) during the first 24 hours, and unable to swallow. The levels of various plasma parameters were determined (glucose, cholesterol, ferritin, etc.) on admission and then every 10 days.

CONCLUSIONS

Plasma ferritin levels higher than those considered normal by the laboratory, in the first few hours after CVA, are an independent predictive factor suggesting unfavourable evolution of the vascular condition. Equally, raised ferritinemia in the first weeks after CVA indicates a worse prognosis. This laboratory test may be carried out on patients with acute CVA to obtain more information on which to base the prognosis.

Renal graft rejection or urinary tract infection? The value of myeloperoxidase, C-reactive protein, and alpha2-macroglobulin in the urine

Previous investigations have shown that the determination of two acute-phase proteins in the urine, C-reactive protein (CRPu) and alpha2-macroglobulin (alpha2-MGu), allows a noninvasive diagnosis of acute renal graft dysfunction. A reliable differentiation between rejection and urinary tract infection can be made only when considering the C-reactive protein in serum and urine at the same time (CRPs:CRPu ratio). Therefore, a diagnostic procedure independent of parameters other than urinary proteins is needed. As granulocytes play only a minor role in graft rejection but are a common feature in urinary tract infection, we determined a marker of granulocytes (myeloperoxidase) in urine (MPOu). Eighty-nine renal transplant recipients were included in the study. In normal courses, CRPu, alpha2-MGu, and MPOu were within the normal range. In 15 cases of acute interstitial rejection, an increased excretion of CRPu and alpha2-MGu could be confirmed, but MPOu could not be detected. On the occasion of acute vascular rejection (n=6), with the exception of one case, MPOu could not be observed. The pattern of the three urinary proteins differed in urinary tract infections (n=40): MPOu could be detected in all cases, CRPu in 50% of cases, and alpha2-MGu in 73% of cases. In patients with cytomegalovirus infection (n=7), no MPOu, CRPu, or alpha2-MGu was found. In conclusion, the simultaneous measurement of the three proteins allows a complete, noninvasive, differential diagnostic procedure of renal graft dysfunction.

[Differential diagnosis of rejection after kidney transplantation. Noninvasive rapid diagnosis by determining special urinary proteins]

Thanks to the use of highly sensitive assays for specific proteins in the urine, it is now possible to obtain, non-invasively and reproducibly, relevant differential diagnostic information when rejection is suspected following renal transplantation. The determination of C-reactive protein and alpha-2 macroglobulin, for example, makes it possible to decide whether a bacterial infection is present or not. Certain constellations of other proteins in the urine permit conclusions to be drawn, for example, as to the presence of CMV infection, the nature of the rejection, transplant glomerulopathy or cyclosporine toxicity. Follow-up studies with the aim of checking the success of treatment, are possible.

[alpha 2-macroglobulin in urine. Significance for differential diagnosis of rejection and infections after kidney transplantation]

The value of measuring the urinary concentration of alpha 2-macroglobulin in addition to that of C-reactive protein (CRP) was assessed in a prospective study of 78 consecutive patients (29 women, 49 men; mean age 48.7 [19-75] years) after renal transplantation. alpha 2-Macroglobulin was never demonstrated in urine when the course was normal (n = 38), cytomegalovirus infection had occurred (n = 26) or acute cyclosporin nephrotoxicity (n = 5) or glomerular disease in the transplant (n = 10). CRP was present in only a few such cases. Interstitial rejections (n = 26) always led to urinary alpha 2-macroglobulin and CRP excretion without haematuria, while in vascular rejection (n = 3) the haemoglobin test was also positive. Urinary infection (n = 20) and urosepticaemia (n = 6) always brought about the urinary excretion of alpha 2-macroglobulin and CRP, as well as a usually highly positive haemoglobin test. alpha 2-Macroglobulin was absent but CRP always present in extrarenal bacterial infections (n = 30). Postrenal blood admixture was always characterized by a positive haemoglobin test and alpha 2-macroglobulin in urine, while in most cases (83%) CRP was absent. --These results indicate that the constellation "alpha 2-macroglobulin negative/CRP positive" is a pathognomonic for extrarenal bacterial infection (sensitivity 100%, specificity 98.9%). The presence of alpha 2-macroglobulin alone makes postrenal blood admixture probable. If both proteins are present in the urine, rejection and urogenital bacterial infection must be excluded by further tests.

Interleukin-6 and interleukin-8 in serum and urine in patients with acute pyelonephritis in relation to bacterial-virulence-associated traits and renal function

Urine and serum concentrations of interleukin (IL)-6 and IL-8 were determined in 43 women with acute pyelonephritis caused by Escherichia coli. Urine and serum samples were also collected 2 weeks after the infection and during a subsequent episode of cystitis (n = 8) or asymptomatic bacteriuria (n = 8). Concentrations of IL-6 and IL-8 were related to the expression of 5 virulence markers of E. coli and glomerular filtration rate (GFR) after pyelonephritis. Patients with acute pyelonephritis had elevated urine and serum IL-6 and IL-8 levels as compared to 37 healthy women (IL-6: p < 0.001 in both cases, and IL-8: p < 0.001 in both cases). Patients infected with E. coli producing hemolysin and/or cytotoxic necrotizing factor (CNF) had significantly higher IL-6 levels in serum during acute pyelonephritis as compared to patients infected with strains without the ability to produce these factors (p = 0.0025 and p = 0.0154, respectively). Patients who had high concentrations of IL-8 in urine during acute pyelonephritis had lower GFR at follow-up as compared to patients with lower levels of IL-8 in urine (r = -0.48, p = 0.0123). In conclusion, acute pyelonephritis is accompanied by elevated urinary and serum IL-6 and IL-8 levels. Bacteria producing hemolysin and CNF seem to induce higher concentrations of IL-6 in serum. The secretion of IL-8 from renal cells may participate in the initiation and maintenance of renal inflammation which in turn may influence renal function.

Urinary trypsin inhibitory activity for the diagnosis of bacterial infection: a prospective study in 690 patients

OBJECTIVES

During the acute phase response, interleukin-1 induces production of inter-alpha-trypsin inhibitor. The measurement of urinary trypsin inhibitory activity which results from the effects of inter-alpha-trypsin inhibitor degradation products is easy, quick and inexpensive. We conducted a prospective study to investigate its value as a diagnostic tool in comparison with C-reactive protein.

METHODS

Comparisons were made in 690 consecutive patients at admission to a department of internal medicine.

RESULTS

The level of urinary trypsin inhibitory activity was significantly higher in patients with bacterial infection (mean = 123 IU/g creatinine) than in patients with either viral infection (34 IU), cancer (50 IU), elevated erythrocyte sedimentation rate without infection (45 IU), miscellaneous non-inflammatory diseases (27 IU) or in non-organic controls (19 IU) (Dunnet's test, p << 0.01). The receiver operating characteristic curve showed that sensitivity and specificity of urinary trypsin inhibitory activity were higher than those of C-Reactive protein for the diagnosis of bacterial infection. For levels > or = 60 IU, sensitivity was 75% and specificity 89%. Urinary trypsin inhibitory activity levels fell within 2 days in patients treated for acute bacterial infection.

CONCLUSION

Urinary trypsin inhibitory activity could be a useful marker of bacterial infection particularly in patients with fever of unknown origin and/or elevated erythrocyte sedimentation rate.

[Urinary trypsin inhibitor as an acute phase reactant]

Early in this century, trypsin inhibiting activity has already been recognized in patients with acute infection or renal disease. In addition to these, conditions such as coronary thrombosis, surgical operation, artificial fever by heat-killed bacilli, malignancy, leukemia, later stage of normal pregnancy, etc. have been known to cause the elevated excretion of UTI in urine. Typically, maximal excretion of UTI has been observed within one or two days after the onset. It appears that recent studies have overcome the complexity of UTI molecule. Automated measurement of urinary trypsin inhibitor (UTI) in urine sample was carried out by either enzymic or immunologic method. UTI as well as erythrocyte sedimentation rate and C-reactive protein enables us to monitor acute phase response, being confirmed in cases of abdominal surgery.

[C-reactive protein in the urine. The differential diagnosis of renal functional disorders following kidney transplantation]

A prospective study was undertaken in 73 patients (24 women, 49 men; mean age 47.9 [21-64] years) after renal transplantation to discover whether the presence of C-reactive protein in urine (CRPu) and its serum concentration (CRPs) are of value in the differential diagnosis of abnormal function in the transplanted kidney. CRPu concentration was measured with a highly sensitive immunoluminometric assay (minimal threshold value 6 micrograms/l). CRPu was demonstrated in 36 histologically proven rejection episodes and 21 bacterial infections proven by culture. In contrast, no CRPu was demonstrated when the course was normal and in individual cases of cyclosporin renal toxicity, as well as in 27 of 34 cases of cytomegalovirus infection. In addition, the CRPs to CRPu ratio was a sensitive means of distinguishing between rejection (CRPs/CRPu less than 1) and bacterial infection (CRPs/CRPu greater than 1). Determining CRPu concentration thus proved to be useful in the initial monitoring of renal transplantation before starting any specific urinary protein diagnosis, as well as (together with CRPs) in the diagnosis of severe posttransplantation complications.

Urinary excretion of the hydroxypyridinium cross links of collagen in patients with rheumatoid arthritis

Values for urinary hydroxypyridinium cross links of collagen measured by high performance liquid chromatography in a group of 19 seropositive patients with rheumatoid arthritis (RA) were compared with 19 controls matched for age and sex. The amounts of pyridinoline, expressed relative to creatinine, were significantly higher in the RA group, but there was no significant increase in a bone specific analogue, deoxypyridinoline. There were significant positive correlations between pyridinoline excretion and both C reactive protein and erythrocyte sedimentation rate, whereas there was an inverse relation with grip strength. The data indicated that pyridinoline concentrations in urine are strongly associated with disease activity in patients with RA.

Effect of diet restriction on 24-hr urinary C-peptide excretion in non-insulin-dependent non-obese diabetic subjects

Changes in insulin secretory responses by diet restriction were analyzed in non-insulin-dependent non-obese diabetic subjects (NIDDM-NO) as well as in healthy volunteers by determining 24-hr urinary C-peptide immunoreactivity (24-hr UCPR). Insulin sensitivity for glucose utilization was measured by using cyclic somatostatin. Overnight fasting plasma glucose concentrations decreased in NIDDM-NO; however, 24-hr UCPR was reduced in both NIDDM-NO and healthy controls by diet restriction (25 kcal/kg) for 14 days. The level of 24-hr UCPR was higher but insulin sensitivity was lower in NIDDM-NO as compared with those in healthy controls. Therefore, diet restriction may be effective in controlling hyperglycemia and hypersecretion of insulin in NIDDM-NO, but it alone may not improve the reduced insulin sensitivity.