Urinary Β2-microglobulin Levels Research Articles

Estimated proximal tubule fluid phosphate concentration and renal tubular damage biomarkers in early stages of chronic kidney disease

IntroductionAn increase in proximal tubule fluid phosphate concentration is caused by increased serum fibroblast growth factor 23 (FGF23) levels, which resulted in renal tubular damage in a mouse model of chronic kidney disease (CKD). However, few human studies have supported this concept. This study aimed to explore the association among estimated proximal tubule fluid phosphate concentration (ePTFp), serum FGF23 levels, and renal tubular damage biomarkers in middle-aged and older populations with mild decline in renal function. MethodsThis cross-sectional study included 218 participants aged ≥45 with CKD stages G2–G4. Anthropometric measurements, blood tests, spot urine biomarkers, renal ultrasonography, cardiovascular assessment, smoking status, and medication usage were obtained in the morning in fasted states. The ePTFp was calculated using serum creatinine, urine phosphate, and creatinine concentrations. Urinary β2-microglobulin and liver-type fatty acid-binding protein (L-FABP) levels were evaluated to assess renal tubular damage.Results: ePTFp, serum FGF23, urinary β2-microglobulin, and urinary L-FABP levels increased with CKD stage progression (stages G2, G3, and G4). However, serum and urine phosphate concentrations were comparable across the CKD stages. Univariate analysis revealed a stronger correlation of ePTFp with serum FGF23, urinary β2-microglobulin, and urinary L-FABP levels than with the corresponding serum and urine phosphate concentrations. Multivariate analyses demonstrated that increased ePTFp was independently associated with elevated serum FGF23 and urinary β2-microglobulin levels, even after adjusting for potential covariates, including the estimated glomerular filtration rate and urinary albumin-to-creatinine ratio. ConclusionsOur results are consistent with the concept in mouse model and suggest that increased ePTFp are associated with increased serum FGF23 levels and renal tubular damage during the early stages of CKD.

Renal tubular necrosis associated with anagrelide administration: a case report.

A 62-year-old female patient with essential thrombocythemia experienced rapid renal dysfunction and was subsequently referred to our hospital. Further investigations did not reveal any significant abnormalities except for a slight increase in urinary β2-microglobulin levels. A renal biopsy was performed to investigate the cause of her renal dysfunction, revealing acute tubular necrosis, interstitial edema, and arteriosclerosis. No significant glomerular lesions were observed. Immunofluorescence staining and electron microscopy showed no abnormalities. She had been using anagrelide for 4years, and her dosage was increased from 2.0 to 3.0mg/day 10months before her initial admission. Her renal function began to deteriorate 2months after the anagrelide dosage increase. Although 0.625mg of bisoprolol was initiated for tachycardia 3months after the anagrelide dosage adjustment, we suspected that the acute tubular necrosis was associated with anagrelide administration. After transitioning from anagrelide to hydroxyurea and discontinuing bisoprolol, her renal function improved. This case suggests the importance of considering anagrelide as a potential cause of renal dysfunction in patients using this medication. Therefore, renal biopsy, combined with a comprehensive medical history, is crucial for evaluating the etiology of renal injury in such cases.

Antenatal Determinants of Postnatal Renal Function in Fetal Megacystis: A Systematic Review.

Introduction: To evaluate the clinical usefulness of demographic data, fetal imaging findings and urinary analytes were used for predicting poor postnatal renal function in children with congenital megacystis. Materials and methods: A systematic review was conducted in MEDLINE's electronic database from inception to December 2023 using various combinations of keywords such as "luto" [All Fields] OR "lower urinary tract obstruction" [All Fields] OR "urethral valves" [All Fields] OR "megacystis" [All Fields] OR "urethral atresia" [All Fields] OR "megalourethra" [All Fields] AND "prenatal ultrasound" [All Fields] OR "maternal ultrasound" [All Fields] OR "ob-stetric ultrasound" [All Fields] OR "anhydramnios" [All Fields] OR "oligohydramnios" [All Fields] OR "renal echogenicity" [All Fields] OR "biomarkers" [All Fields] OR "fetal urine" [All Fields] OR "amniotic fluid" [All Fields] OR "beta2 microglobulin" [All Fields] OR "osmolarity" [All Fields] OR "proteome" [All Fields] AND "outcomes" [All Fields] OR "prognosis" [All Fields] OR "staging" [All Fields] OR "prognostic factors" [All Fields] OR "predictors" [All Fields] OR "renal function" [All Fields] OR "kidney function" [All Fields] OR "renal failure" [All Fields]. Two reviewers independently selected the articles in which the accuracy of prenatal imaging findings and fetal urinary analytes were evaluated to predict postnatal renal function. Results: Out of the 727 articles analyzed, 20 met the selection criteria, including 1049 fetuses. Regarding fetal imaging findings, the predictive value of the amniotic fluid was investigated by 15 articles, the renal appearance by 11, bladder findings by 4, and ureteral dilatation by 2. The postnatal renal function showed a statistically significant relationship with the occurrence of oligo- or anhydramnion in four studies, with an abnormal echogenic/cystic renal cortical appearance in three studies. Single articles proved the statistical prognostic value of the amniotic fluid index, the renal parenchymal area, the apparent diffusion coefficient (ADC) measured on fetal diffusion-weighted MRI, and the lower urinary tract obstruction (LUTO) stage (based on bladder volume at referral and gestational age at the appearance of oligo- or anhydramnios). Regarding the predictive value of fetal urinary analytes, sodium and β2-microglobulin were the two most common urinary analytes investigated (n = 10 articles), followed by calcium (n = 6), chloride (n = 5), urinary osmolarity (n = 4), and total protein (n = 3). Phosphorus, glucose, creatinine, and urea were analyzed by two articles, and ammonium, potassium, N-Acetyl-l3-D-glucosaminidase, and microalbumin were investigated by one article. The majority of the studies (n = 8) failed to prove the prognostic value of fetal urinary analytes. However, two studies showed that a favorable urinary biochemistry profile (made up of sodium < 100 mg/dL; calcium < 8 mg/dL; osmolality < 200 mOsm/L; β2-microglobulin < 4 mg/L; total protein < 20 mg/dL) could predict good postnatal renal outcomes with statistical significance and urinary levels of β2-microglobulin were significantly higher in fetuses that developed an impaired renal function in childhood (10.9 ± 5.0 mg/L vs. 1.3 ± 0.2 mg/L, p-value < 0.05). Conclusions: Several demographic data, fetal imaging parameters, and urinary analytes have been shown to play a role in reliably triaging fetuses with megacystis for the risk of adverse postnatal renal outcomes. We believe that this systematic review can help clinicians for counseling parents on the prognoses of their infants and identifying the selected cases eligible for antenatal intervention.

A case of tubulointerstitial nephritis and uveitis syndrome accompanied by subclinical choroiditis

BackgroundTubulointerstitial nephritis and uveitis (TINU) syndrome is an uveits characterized by complications of idiopathic acute tubulointerstitial nephritis, and most cases present only anterior uveitis. We report a case of TINU syndrome in which the presence of choroiditis was revealed by multimodal imaging.Case presentationA 12-year-old male visited our hospital with a 6-day history of ocular pain and hyperemia. Conjunctival and ciliary injections, 1 + flare and 3 + cells of anterior chamber inflammation with mutton fat keratic precipitates were observed in both eyes (OU), together with redness and swelling of the optic disc OU. Laboratory tests showed slightly high levels of soluble IL-2R and serum β2 microglobulin and markedly high levels of urinary β2 microglobulin. The diagnosis of probable TINU syndrome was established on the basis of bilateral uveitis and urinalysis results in accordance with a clinical criteria of tubulointerstitial nephritis. With treatment with oral prednisolone (PSL) at 20 mg/day, ocular findings improved, and the dose of PSL was gradually reduced and withdrawn 6 months later. However, 1 month later from the withdrawal, ocular inflammation recurred with the presence of retinal exudates and snowball vitreous opacities in the peripheral retina OU. Fluorescein angiography showed leakages from peripheral retinal vessels and staining corresponding to retinal exudates. Indocyanine green angiography showed hypofluorescent dots scattered over the ocular fundus. Optical coherence tomography revealed the presence of choroidal thickening. Laser speckle flowgraphy color map showed a relatively cooler color. Findings from these multimodal images indicated the presence of subclinical choroiditis; therefore, oral PSL was administered again, and ocular inflammatory findings were improved.ConclusionsTINU syndrome can exhibit subclinical choroiditis detected with multimodal imaging. Further studies are necessary to determine the frequency of subclinical choroiditis in TINU syndrome.

Evidence Linking Cadmium Exposure and β2-Microglobulin to Increased Risk of Hypertension in Diabetes Type 2.

The most common causes of chronic kidney disease, diabetes, and hypertension are significant public health issues worldwide. Exposure to the heavy metal pollutant, cadmium (Cd), which is particularly damaging to the kidney, has been associated with both risk factors. Increased levels of urinary β2-microglobulin (β2M) have been used to signify Cd-induced kidney damage and circulating levels have been linked to blood pressure control. In this study we investigated the pressor effects of Cd and β2M in 88 diabetics and 88 non-diabetic controls, matched by age, gender and locality. The overall mean serum β2M was 5.98 mg/L, while mean blood Cd and Cd excretion normalized to creatinine clearance (Ccr) as ECd/Ccr were 0.59 µg/L and 0.0084 µg/L of filtrate (0.95 µg/g creatinine), respectively. The prevalence odds ratio for hypertension rose by 79% per every ten-fold increase in blood Cd concentration. In all subjects, systolic blood pressure (SBP) showed positive associations with age (β = 0.247), serum β2M (β = 0.230), and ECd/Ccr (β = 0.167). In subgroup analysis, SBP showed a strong positive association with ECd/Ccr (β = 0.303) only in the diabetic group. The covariate-adjusted mean SBP in the diabetics of the highest ECd/Ccr tertile was 13.8 mmHg higher, compared to the lowest tertile (p = 0.027). An increase in SBP associated with Cd exposure was insignificant in non-diabetics. Thus, for the first time, we have demonstrated an independent effect of Cd and β2M on blood pressure, thereby implicating both Cd exposure and β2M in the development of hypertension, especially in diabetics.

An Infant Case of Transient Distal Renal Tubular Acidosis and Fanconi Syndrome Caused by Rotavirus Gastroenteritis.

We report an infant case of transient distal renal tubular acidosis and Fanconi syndrome caused by rotavirus gastroenteritis. A 10-month-old boy was admitted to the hospital because of frequent vomiting, lack of vitality, and dehydration. He was diagnosed with rotavirus gastroenteritis on account of his positive stool rotavirus antigen test. Although he presented with acidemia and severe mixed metabolic acidosis, he also had a urine pH of 6.0, indicating impaired urinary acidification. Therefore, he was diagnosed with distal renal tubular acidosis. On the third day of hospitalization, a relatively low %tubular reabsorption of phosphate level with hypophosphatemia, increased fractional excretion of uric acid with hypouricemia, and high urinary β2-microglobulin levels were observed. Moreover, he was diagnosed with Fanconi syndrome on account of multiple proximal tubular dysfunctions. After remission of rotavirus gastroenteritis, the signs of renal tubular dysfunction improved. This was a case of rotavirus gastroenteritis-caused transient distal renal tubular acidosis and Fanconi syndrome. Severe metabolic acidosis resulted from anion-gap metabolic acidosis due to acute kidney injury by rotavirus gastroenteritis and normal anion-gap acidosis due to renal tubular acidosis. When renal tubular acidosis is associated with a disease that causes anion-gap metabolic acidosis, mixed metabolic acidosis occurs and becomes exacerbated. Furthermore, it is important to consider the complications of renal tubular acidosis in the case of severe metabolic acidosis.

Can Steroid Response in Idiopathic Childhood Nephrotic Syndrome be Predicted? A Single Center Quasi-Experimental Study

Objective: To predict the role of clinical risk factors and urinary β2-microglobulin levels as a biomarker for steroid-resistant nephrotic syndrome.&#x0D; Study Design: Quasi-experimental study.&#x0D; Place and Duration of Study: Paediatric Nephrology Department, Sindh Institute of Urology and Transplantation, Karachi Pakistan, from Jun 2019 to Nov 2020.&#x0D; Methodology: All children (3 months to 12 years) with either first episode or relapse of the nephrotic syndrome were included. A stored urine sample was used on 100 patients with steroid-sensitive (group-1) and 35 patients with steroid-resistant nephrotic syndrome (group-2). In addition, histopathology of all patients with steroid-resistant nephrotic syndrome was recorded.&#x0D; Results: Both groups and those who had focal segmental glomerulosclerosis were compared and analysed to evaluate the predictability of steroid response. There was a significant association in both groups for microscopic haematuria, hypertension, heavy proteinuria (urine spot protein to creatinine ratio &gt;10 g/g) and increased β2-microglobulin levels (&gt; 3× normal) as individual risk factors (p&lt;0.01). The sensitivity of β2-microglobulin levels was 78% and a positive predictive value of 80%. Multivariate regression analysis on steroid-resistant nephrotic syndrome as a group did not confer a higher risk; however, for children with focal segmental glomerulosclerosis, the likelihood of steroid unresponsiveness was significantly higher for the same parameters.&#x0D; Conclusion: The addition of biomarker measurement and known clinical risk factors helped predict steroid-resistant focal segmental glomerulosclerosis. However, further studies are warranted before these results can be generalized.

Identification of VEGF Signaling Inhibition-Induced Glomerular Injury in Rats through Site-Specific Urinary Biomarkers.

Cancer therapies targeting the vascular endothelial growth factor (VEGF) signaling pathway can lead to renal damage by disrupting the glomerular ultrafiltration apparatus. The objective of the current study was to identify sensitive biomarkers for VEGF inhibition-induced glomerular changes in rats. Male Sprague-Dawley rats were administered an experimental VEGF receptor (VEGFR) inhibitor, ABT-123, for seven days to investigate the correlation of several biomarkers with microscopic and ultrastructural changes. Glomeruli obtained by laser capture microdissection were also subjected to gene expression analysis to investigate the underlying molecular events of VEGFR inhibition in glomerulus. ABT-123 induced characteristic glomerular ultrastructural changes in rats, including fusion of podocyte foot processes, the presence of subendothelial electron-dense deposits, and swelling and loss of fenestrations in glomerular endothelium. The subtle morphological changes cannot be detected with light microscopy or by changes in standard clinical chemistry and urinalysis. However, urinary albumin increased 44-fold as early as Day three. Urinary β2-microglobulin levels were also increased. Other urinary biomarkers that are typically associated with tubular injury were not significantly impacted. Such patterns in urinary biomarkers can provide valuable diagnostic insight to VEGF inhibition therapy-induced glomeruli injuries.

Frequency domain analysis and clinical outcomes of pulsatile and non-pulsatile blood flow energy during cardiopulmonary bypass.

The superiority of pulsatile perfusion during cardiopulmonary bypass remains controversial. We analyzed the frequency-domain characteristics and organ protection of pulsatile and nonpulsatile flow in adult patients with valvular disease. EEP and SHE were used to calculate blood flow energy in 60 patients. The Fast Fourier Transform was employed to analyze the power spectral density and power density ratio (Rvpd) of flow energy. Changes in endothelin-1, nitric oxide, interleukin-6,10, tumor necrotic factor, S100β, NSE, blood and urinary β2-microglobulin levels were investigated to assess the endothelial function, inflammatory reaction, kidney and brain injury during CPB. EEP and SHE in PP group at each time point were 1.52-1.62 times and 2.03-2.22 times higher respectively compared with NP group. Power spectral density analysis demonstrated that the blood flow energy frequencies in each group were all within 40 Hz and the low frequency energy (0-5 Hz) was dominant in physiological perfusion (>90%). The energy ratio of 0-5 Hz at radial artery was significantly decreased compared with that of post arterial filter in PP (81% vs 64%) and NP (63% vs 37%) group. The power density ratio (Rvpd) was higher than that of NP in all frequency ranges at the radial artery (9.51 vs 4.68 vs 3.59) and arterial filter (3.87 vs 2.69 vs 2.38). The S100β, NSE Urinary and plasma β2-microglobulin level were significantly increased at 6 and 24 hours after surgery in two group, and significantly higher in group NP. PP provided more energy than NP. The proportion of low frequency energy in the pulsatile or nonpulsatile flow is significantly reduced. The low-frequency energy is significantly attenuated during conduction to peripheral tissues in nonpulsatile flow. The surplus pulsatile energy influences the secretion of endothelial and inflammatory factors, and demonstrate better cerebral and kidney protective effect at the biological marker level.

Elevated cadmium and 8-hydroxy-2'-deoxyguanosine (8-OHdG) levels in residents living near electroplating industries.

This study aims to evaluate the body burdens of cadmium (Cd) associated with potential health impairment in residents living near electroplating industries. A total of 269 residents from exposure area and 106 from control area were recruited. We measured the blood and urinary Cd levels using an inductively coupled plasma mass spectrometer (ICP-MS); performed physical examinations; determined the urinary levels of β2-microglobulin (β2-MG), Nacetyl-β-D-glucosaminidase (NAG), and 8-hydroxy-2'-deoxyguanosine (8-OHdG); and evaluated the associations between Cd and these biomarkers. Blood and urinary Cd levels in exposure group were statistically higher than in control group (1.712 vs. 1.159 μg/L; 1.980 vs. 1.740 μg/L, respectively, p < 0.05). Urinary β2-MG and 8-OHdG levels in exposure group were also statistically higher (0.448 vs. 0.090 mg/L; 12.759 vs. 12.115 μg/L, respectively, p < 0.05), but urinary NAG levels showed no significant difference between the two groups (13.614 vs. 8.246 IU/L, p > 0.05). The proportion of abnormal nasal symptoms occurring in exposed subjects (88.8%) was much higher than in control subjects (78.2%, p < 0.05). Urinary Cd levels were positively correlated with blood Cd levels, urinary 8-OHdG, and NAG levels (r = 0.307, r = 0.185, r = 0.150, p < 0.05), but not correlated with urinary β2-MG levels (p > 0.05). In conclusion, our study revealed that residents living in close proximity to electroplating industries had elevated body burdens of Cd levels, as well as slight renal dysfunction and DNA oxidation damage.

Environmental cadmium exposure induces kidney tubular and glomerular dysfunction in the Myanmar adults.

Cadmium is an environmental toxic metal and its exposure has become a worldwide public health threat. We aimed to evaluate the exposure assessment of cadmium in people living in Ta Zin Yae Kyaw village of Nyaung Don Township in Ayeyarwady Division, Myanmar and adverse effects of cadmium on the kidneys. Subjects (18-40 years) residing in this village were selected as the exposed group (n = 65) and those living in Kamayut Township in Yangon Division, Myanmar as the control group (n = 65). Spot urine samples were taken for determination of urinary cadmium concentration using graphite-furnace atomic absorption spectrometry (GFAAS) method and adjusted to the concentration of creatinine in urine. To assess the kidney function, urinary β2-microglobulin level was determined by ELISA, serum creatinine was measured by colorimetric Jaffe method and estimated glomerular filtration rate (eGFR) was calculated by Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation. Urine cadmium concentrations were significantly higher in the exposed group (median (Interquartile range): 0.96 (0.19-1.77) μg/g Creatinine) compared to the control (p = 0.036). Urinary β2-microglobulin levels were significantly higher (p = 0.000) and eGFR was significantly lower in the exposed group (p = 0.013) compared to the control. In addition, urine cadmium level showed significant positive correlation with urinary β2-microglobulin in all study population (p < 0.01). Positive correlation becomes stronger (p < 0.01) in the exposed group only. For eGFR, significant negative correlation was found in all study population (p < 0.01) and exposed group (p < 0.01). Our findings suggested that environmental cadmium exposure can induce renal dysfunction in both tubular and glomerular functions in apparently healthy human adults.

Tubular Injury Causing Protracted Glycosuria Following Withdrawal of a Sodium-Glucose Cotransporter 2 (SGLT2) Inhibitor: A Possible Role in the Development of Protracted Hypoglycemia and Ketoacidosis.

We herein present the case of a 45-year-old diabetic woman who developed diabetic ketoacidosis following the administration of dapagliflozin, a sodium-glucose cotransporter 2 (SGLT2) inhibitor. The patient had been diagnosed with diabetes three years previously and was being treated with multiple daily injections of insulin. Metformin hydrochloride and dapagliflozin were added seven months and 11 months later, respectively. Her clinical course was uneventful until the onset of influenza. She then discontinued insulin and oral medications voluntarily. On arrival at the hospital, she was found to be in a state of ketoacidosis, and promptly received insulin and saline infusion. In retrospect, the initial amount of glucose infused was insufficient, and the hypoglycemia was thought to have been prolonged. This phenomenon may also have affected her long-term urinary glucose excretion. Her urinary L-type fatty acid-binding protein (L-FABP) level was found to be markedly elevated (48.8 μg/g·Cr, reference value < 8.4 μg/g·Cr) as was her urinary β2-microglobulin level (9,230 μg/L, reference value < 230 μg/L). Patients with SGLT-2 inhibitor-associated diabetic ketoacidosis often exhibit protracted hyperglycosuria, in which acute proximal renal tubular dysfunction is considered to be etiologically implicated.

Hyperechogenic Fetal Kidneys: Uncertain Diagnosis and Unpredictable Future?

AbstractGlomerulocystic kidney with increased renal echogenicity encompasses a number of renal abnormalities that might have cystic glomeruli and be a sequelae of renal obstruction. Increased echogenicity of the kidneys is a non-specific finding and a result of varied etiologies. Multiple microscopic cortical and medullary cysts, interstitial fibrosis and mesangial sclerosis are the etiopathogenesis for renal hyperechogenicity even in the absence of macrocysts. The crucial point is poor predictability of antenatal ultrasound to fully define the extent and severity of parenchymal damage and to forecast its outcome at the time of initial diagnosis. The only exception is the most severe forms of cystic dysplasia associated with severe oligohydramnios. Urinary levels of β2-microglobulin may be a valuable marker of fetal renal function. Hyperechogenic fetal kidneys may have varied etiologies and within each etiological group there may have a wide range of outcomes. Challenges lie in counseling after antenatal diagnosis of fetal hyperechogenic kidneys which carry an uncertain course and prognosis.

Risk factors for cisplatin-induced acute kidney injury: A pilot study on the usefulness of genetic variants for predicting nephrotoxicity in clinical practice.

Several studies have reported risk factors for predicting cisplatin-induced acute kidney injury (AKI), including old age, female sex, smoking, hypoalbuminemia, hypokalemia, hypomagnesemia, a high body surface area, advanced cancer and the total dose of cisplatin administered. Recently, some studies have focused on the associations between genetic alterations in the genes coding for renal drug transporters, such as organic cation transporter 2 (OCT2), and the nephrotoxicity of cisplatin. However, genetic variants have not been fully elucidated for clinical use. Patients who had received cisplatin (≥50 mg/m2)-containing chemotherapy as a first-line treatment were considered as eligible for the present study. The occurrence of AKI and its associations with baseline characteristics, conventional biomarkers and single-nucleotide variants (SNV) were assessed. AKI was defined as an increase in the serum creatinine level of >0.3 mg/dl or to 1.5-2 times the baseline level. Genotyping was conducted using the DMET platform (DMET Plus), which characterizes 1,936 genetic variants (1,931 SNV and 5 copy number variations) in 231 genes. Between April 2014 and June 2016, a total of 28 patients (22 men and 6 women) were enrolled. AKI occurred in 8 of the 28 enrolled patients (28.6%). Univariate analyses demonstrated that the urinary β2-microglobulin level and body surface area were significantly higher in the AKI group (P<0.05). As regards the associations between AKI and SNV, none of the examined SNV were found to be associated with cisplatin-induced AKI. The findings of the present study suggested that certain clinical factors were associated with the onset of AKI, but no associations were identified with genetic factors, including OCT2. Although this was a small pilot study, the findings indicated that genetic factors may not be of value for predicting AKI in clinical practice.

Clinicopathological feature analysis of IgA nephropathy complicated with acute kidney injury in children

Objective To investigate the clinicopathological features of IgA nephropathy(IgAN) complicated with acute kidney injury (AKI) in children. Methods The clinical and pathological data of children with biopsy-proven primary IgAN and complicated with AKI from January 2012 to December 2016 in the First Affiliated Hospital of Zhengzhou University were analyzed retrospectively, and the data of macroscopic hematuria (MH) associated AKI(15 cases) and other MH without AKI(99 cases) were compared. Results (1) Among 211 patients diagnosed with IgAN, 21 (9.95%) patients were complicated with AKI.Among the 21 cases, the average age was (9.5±2.1) years old, in which 17 cases(80.9%) were males, 19 cases with MH, and the range of the peak serum creatinine was 93-627 μmol/L.In histology, cellular/fibrocellular crescents were found in 11 cases, while high proportion of tubules filled with red blood cell(RBC) casts were observed in 8 cases, and moderate to severe acute tubular injury (ATI) were observed in 16 cases.In 2 cases, extensively mixed inflammatory cell infiltration with eosinophils was present in the interstitium.(2) According to the clinical and pathological characteristics, the 21 cases were divided into 3 groups: 15 cases with MH related AKI, 4 cases with crescentic glomerulonephritis, and 2 cases with acute interstitial nephritis.Compared with MH without AKI group(99 cases), the MH associated AKI group(15 cases) had significantly longer duration of MH, higher proteinuria level, urinary levels of β2-microglobulin (β2-MG) and N-acetyl-β-D-glucosaminidase (NAG), and greater frequency of RBC casts and ATI, and the differences were statistically significant(all P<0.05). In 2 acute interstitial nephritis cases, one had a history of taking weight loss drug with unknown ingredients, while the specific cause of the other was not clear.(3) None of the patients was on dialysis, but corticosteroid was prescribed in 17 cases (including methylprednisolone pulse therapy in 6), and 3 cases were combined with cyclophosphamide.Almost all patients achieved normal renal function except for one who had no response within 2 months after treatment.The median follow-up period was 24 months, in which 1 patient with crescentic glomerulonephritis progressed to end-stage renal disease. Conclusions AKI is commonly seen in children with IgAN, and complete recovery of renal function was seen in all patients with MH associated AKI and acute interstitial nephritis. Key words: IgA nephropathy; Acute kidney injury; Macroscopic hematuria; Child

Association between urinary biomarkers and disease progression in adults with autosomal dominant polycystic kidney disease.

BackgroundHeight-adjusted total kidney volume (htTKV) is considered as the best predictor of kidney function in patients with autosomal dominant polycystic kidney disease (ADPKD), but its limited predictive capacity stresses the need to find new biomarkers of ADPKD progression. The aim of this study was to investigate urinary biomarkers of ADPKD progression.Methods This observational study included ADPKD patients, and two comparator groups of ischaemic and non-ischaemic kidney injury: benign nephroangiosclerosis patients and non-ischaemic chronic kidney disease (CKD) patients. Proteinuria, htTKV and urinary levels of molecules are associated with ischaemia and/or tubular injury. The slope of estimated glomerular filtration rate (eGFR) was used as a dependent variable in univariate and multivariate models of kidney function decline.ResultsThe study included 130 patients with ADPKD, 55 with nephroangiosclerosis and 40 with non-ischaemic CKD. All patients had increased urinary concentrations of biomarkers associated with tubular lesions (liver fatty acid-binding protein, kidney injury molecule-1, β2-microglobulin) and molecules overexpressed under ischaemic conditions [hypoxia-inducible factor-1α, vascular endothelial growth factor (VEGF) and monocyte chemoattractant protein-1 (MCP-1)]. These biomarkers correlated positively with htTKV and negatively with the eGFR slope. htTKV was the single best predictor of the eGFR slope variability in univariate analyses. However, a multivariate model including urinary levels of β2-microglobulin, MCP-1 and VEGF improved the capacity to predict the decline of eGFR in ADPKD patients compared with htTKV alone.ConclusionsThe urinary levels of molecules associated with either renal ischaemia (VEGF and MCP-1) or tubular damage (β2-microglobulin) are associated with renal function deterioration in ADPKD patients, and are, therefore, candidates as biomarkers of ADPKD progression.

Correlation between renal pelvic pressure and renal oxidative stress and microinflammation in ureteral lithotripsy

Objective To investigate the effects of ureteral pressure changes on oxidative stress and microinflammation in patients with ureteral lithotripsy. Methods From December 2016 to January 2018, 100 patients with renal calculi underwent ureteroscopic lithotripsy were treated in hospital. The ureteral pressure was monitored during operation. The patients with intraoperative ureteral pressure≥40 cmHg and cumulative time≥10 min were used as the high pressure group. The other patients were used as the low-pressure group. The urine microalbumin, urinary β2-microglobulin level, serum high-sensitivity C-reactive protein, interleukin-6, superoxide dismutase, malondialdehyde, glutathione level were measured before and at 1, 3, 5, and 7 days after operation. Results The blood pressure and heart rate of the two groups were not obvious after operation(P>0.05). The levels of urinary microalbumin, urinary β2-microglobulin, serum high-sensitivity C-reactive protein and interleukin-6 malondialdehyde were significantly increased (P<0.05), but the high-pressure group was in-creased higher significantly (P<0.05), superoxide dismutase and glutathione were significantly lower (P<0.05), and the high pressure group was more significantly (P<0.05). Pearson correlation analysis showed that renal pelvic pressure was positively correlated with urinary β2-microglobulin, serum high-sensitivity C-reactive protein, and malondialdehyde (r=0.716, 0.654, 0.632, P<0.05), and superoxide dismutase. There was a significant negative correlation with glutathione (r=-0.702, -0.711, P<0.05). Conclusions In patients with ureteroscopic lithotripsy, renal pelvic hypertension leads to renal dysfunction, inflammation and redox imbalance. Intraoperative control of renal pelvic pressure is beneficial to restore renal function and avoid further damage to renal function. Key words: Lithotripsy, Laser; Oxidative Stress; Inflammation

Association of liver and kidney functions with Klotho gene methylation in a population environment exposed to cadmium in China

ABSTRACTExposure to the heavy metal cadmium has adverse effects on human health, including DNA methylation. This study aimed to investigate the effects of cadmium on liver and kidney functions and Klotho gene methylation and to explore the relationship of methylation level with indicators of liver and kidney functions. Graphite furnace atomic absorption spectrometry was conducted to determine urinary cadmium, and an automatic biochemical analyzer was used to detect indices of liver and kidney functions. PCR pyrosequencing was performed to detect the methylation rate of Klotho. One-way ANOVA was adopted to compare the differences between groups, and the linear correlation to variables was analyzed. Cadmium exposure was negatively correlated with albumin level (r=-0.143, p=0.021) and positively correlated with urinary β2-microglobulin level (r=0.229, p<0.001). However, the methylation levels of Klotho gene was decreased and increased by low and high doses of cadmium exposure, respectively. And Klothomethylation levels were negatively correlated with albumin levels and positively correlated with β2-microglobulin levels.In this study, cadmium exposure affects liver and kidney functions as well as Klotho methylation levels, but the effect on Klotho methylation levels is not linear. Klotho methylation levels also influence liver and kidney functions.

Glomerular and Tubular Functions in Children and Adults with Transfusion-Dependent Thalassemia.

This study aimed at assessing renal functions in patients with transfusion-dependent thalassemia (TDT). Fifty patients and 30 controls were enrolled in this prospective study. Serum levels of electrolytes and albumin were measured by a spectrophotometer. Serum levels of cystatin-C and urinary levels of β2-microglobulin were measured by nephelometric method. Thirty-eight patients were receiving deferasirox and 8 were on deferiprone. Serum electrolytes and albumin levels of the patients were found to be within normal ranges. Urinary β2-microglobulin and serum cystatin-C levels were significantly higher in patients than controls. They did not significantly differ between the subgroup of patients on deferiprone and the control group, whereas they were found to be higher in patients using deferasirox compared to controls. Urinary β2-microglobulin levels significantly increased in patients who were receiving high-dose deferasirox compared to those who were receiving a daily dose of 15-20 mg/kg or controls. Subclinical renal injury may be present in TDT patients.

Clinical and Genetic Features of Tubulointerstitial Nephritis and Uveitis Syndrome with Long-Term Follow-Up.

Purpose To investigate the clinical manifestations, prognosis, and HLA-type of tubulointerstitial nephritis and uveitis syndrome (TINU) with long-term follow-up. Methods Clinical data of five patients with TINU were retrospectively reviewed. Results The mean age was 15.8 years. The mean follow-up periods were 54.0 months. The initial subjective symptoms were bulbar injection (100%), ocular pain (80%), and blurred vision (60%). The medical department that the patients visited first was ophthalmology in 4 (80%) cases. Urinalysis showed the characteristic increase of the β2 microglobulin in all (100%) patients. Uveitis and nephritis were diagnosed within 1 week from each other. Although two showed recurrences, the topical and systemic steroid treatment with mean duration of 14.1 months brought the resolution of nephritis and uveitis in all patients. Recurrence-free periods ranged from 12 to 71 months. The final visual outcome was 20/20 or better in all cases. HLA-DR4 or the allele of DRB1∗04 was present in all (100%) patients. Conclusions TINU should be considered in the differential diagnosis in young patients with uveitis of unknown origin and renal dysfunction. Urinary β2 microglobulin level and HLA typing may help in the diagnosis of TINU. The prognosis for patients with TINU is generally good with steroid treatment.