Leptin,soluble leptin receptor,and transforming growth factor-β1 levels in minimal change nephrotic syndrome

Leptin may contribute to renal pathology in some situations by stimulating transforming growth factor-1 (TGF-1) synthesis. The soluble leptin receptor (sOb-R) is a transport protein contributing to binding and activation of circulating leptin. We investigated the interaction between serum and urinary leptin, TGF-1, and serum sOb-R levels in 38 patients with minimal change nephrotic syndrome (MCNS) aged between 6 and 12 years and 10 age- and sex-matched healthy controls (group III). Patients were divided into two groups: group I, proteinuria exceeding >40 mg/m² per hour and group II, patients in remission. Serum leptin levels in group I were significantly lower than those in group II and group III (P=0.011, P=0.007, respectively). There was a negative correlation between serum leptin levels and proteinuria (r=–0.52, P=0.02) as well as between serum leptin and sOb-R levels (r=–0.82, P=0.000) in group I. Urine leptin and sOb-R levels in group I were significantly higher than in group II (P=0.0021, P=0.001, respectively) and group III (P=0.07, P=0.009, respectively). Serum TGF-1 levels in healthy controls (406±424 pg/ml) were significantly lower than those in groups I and II (P=0.004, P=0.000, respectively). However, no significant correlation was found between the serum TGF-1 and leptin levels in MCNS patients. In conclusion, low serum leptin, high serum TGF-1 and sOb-R levels, and elevated urine leptin concentrations were observed at the onset of MCNS. Since long-term proteinuria and leptinuria might be associated with the progression of renal damage, future in vivo and in vitro studies are needed to explain the interaction between these parameters in different types of nephrotic syndrome.     

Sodium dodecyl sulphate polyacrylamide gel electrophoresis patterns of proteinuria in various renal diseases of childhood

This study examined the potential of an automated electrophoretic system (PHASTSYSTEM, Pharmacia, Uppsala, Sweden) to distinguish patterns of proteinuria in children with various renal diseases. It proved possible to produce ready-to-read sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS PAGE) separation of 1 l of unconcentrated urine in 2 h. Glomerular, tubular and mixed patterns of proteinuria were identified. Steroid-responsive nephrotic syndrome (SRNS) was readily identified by strong bands of albumin and transferrin during relapses. In contrast, steroid-resistant nephrotic syndrome was associated with two additional bands of haptoglobin and IgG. Albumin dimers (M _r 120 kDa) were found in the active phase of the disease in the urine of 90% of children with SRNS. Patterns of tubular proteinuria were found in children with proximal renal tubular abnormalities. The presence of mixed patterns of glomerular and tubular proteinuria strongly suggest renal insufficiency. SDS PAGE electrophoresis can readily be applied in clinical practice. It may prove helpful in the diagnosis and management of children with renal diseases enabling correlation to be made between proteinuria, renal pathology and prognosis.     

Atopy,serum IgE,and interleukin-13 in steroid-responsive nephrotic syndrome

Earlier studies have demonstrated a strong association of steroid-responsive nephrotic syndrome (SRNS), atopy, and elevated serum IgE levels. Interleukin (IL-13) gene expression is significantly increased in children with SRNS in relapse. As interferon (IFN)-, IL-13, and IL-4 have regulatory effects on IgE synthesis, we examined the relationship between intracellular cytokine production and serum IgE levels in children with SRNS, in order to further define the reported association with atopy. The median serum IgE levels in nephrotic patients in relapse with (492 U/ml) or without atopy (561 U/ml) were significantly higher than those in remission (221 U/ml, P<0.002 or 90 U/ml, P<0.001, respectively) and non-atopic controls (177 U/ml) (P<0.001). The percentage of CD3+ IL-13-producing cells was significantly higher in nephrotic children in relapse, and correlated with the serum IgE levels during the active phase of the disease (r=0.90, P<0.001). These data suggest that the elevated serum IgE levels during relapses of SRNS were the result of upregulation of IL-13. This probably reflects some common immune activation following various stimuli, rather than a direct association with atopy.     

Urinary <Emphasis Type="Italic">N</Emphasis>-acetyl-beta-<Emphasis Type="SmallCaps">D</Emphasis> glucosaminidase (NAG) level in idiopathic nephrotic syndrome

Urinary N-acetyl-beta-D glucosaminidase (NAG) is a sensitive biomarker of renal parenchymal disease. The aim of this study was to investigate variations in the levels of NAG excretion among different sub-groups of nephrotic syndrome (first episode, relapsers, and resistant) and its prediction based on proteinuria. Thirty-five patients with idiopathic nephrotic syndrome, aged 1–12 years, as well as 15 age- and gender-matched normal children (controls) were enrolled in the study. Among the 35 patients, ten were classified with first episode nephrotic syndrome (FENS), 17 with relapsing nephrotic syndrome (RNS), and eight with steroid-resistant nephrotic syndrome (SRNS). Urinary NAG/creatinine levels were significantly increased in SRNS patients as compared to FENS and RNS patients (p < 0.001); the FENS and RNS groups had comparable levels. A urinary NAG/creatinine value of ≤108.9 U/g was found to identify steroid-sensitive patients with a sensitivity, specificity, positive predictive value, and negative predictive value of 78.8, 100, 100 and 77.7%, respectively. Significant correlations were found between experimental and predicted values of urinary NAG/creatinine in steroid sensitive nephrotic syndrome (SSNS) (R ² = 0.9643) and SRNS patients (R ² = 0.9823). Urinary NAG/creatinine values were found to be higher in SRNS than SSNS patients and have moderate predictive value for steroid responsiveness. This level can be obtained based on urinary protein/creatinine ratio or 24 h urinary protein levels.     

Low protein Z levels in children with nephrotic syndrome

Acquired deficiency of anticoagulant proteins, due to loss in the urine, has been proposed as one of the major thrombogenic alterations in nephrotic syndrome (NS). Protein Z (PZ) is a single-chain vitamin K-dependent glycoprotein. Low PZ levels are reported to be a risk factor for thrombosis. The aim of this study was to investigate protein Z and other natural anticoagulant levels in children with NS. Thirty children aged between 1.5 and 12 years with NS (Groups I and II) and 19 age-and-sex-matched healthy controls (Group III) were enrolled into the study. Patients were divided into two groups: Group I (proteinuria >40 mg/m²/hr) and Group II (patients in remission). Plasma PZ levels in Group I were significantly lower than Group II (p=0.009) and group III (p=0.018). Plasma levels of AT III for Group I were significantly lower than for Groups II and III (p=0.009, p=0.005, respectively). Protein C levels in Group I were higher than in Group II and Group III (p=0.002, p=0.000, respectively). Protein Z levels positively correlated with serum total protein and albumin levels (p=0.003, p=0.003, respectively) and negatively with the degree of proteinuria (p=0.000). Protein Z levels were positively correlated with AT III (r=0.037, p=0.04). Along with the other coagulation abnormalities, decreased protein Z may contribute to increased risk of thromboembolic complications in children with NS. The negative correlation between proteinuria and PZ level suggests the possibility of renal PZ loss. Further studies are needed to investigate the mechanism and role of decreased PZ in NS.     

Follow-up of steroid-resistant nephrotic syndrome: tubular proteinuria and enzymuria

The aim of this study was to examine the compromise of proximal tubule cells in steroid-resistant nephrotic syndrome patients with a histologic diagnosis of focal segmental glomerulosclerosis (FSGS) through assessment of the urinary levels of β₂-microglobulin (β₂M) and N-acetyl-β-d-glucosaminidase (NAG) during active disease and remission over a follow-up period of 3 years. We studied 34 children with nephrotic syndrome: 12 with steroid-resistant nephrotic syndrome (SRNS) and massive proteinuria, 7 with steroid-dependent nephrotic syndrome (SDNS) and 15 with steroid-sensitive nephrotic syndrome (SSNS). Of the SSNS patients, 8 children were in remission (RM) and 7 were in relapse (RL). Seven healthy children were included as controls. Urinary β₂M, measured by enzyme-linked immunosorbent assay, was significantly increased in the SRNS group as compared to the SDNS group (P<0.01), SSNS in remission (P<0.01), and controls (P<0.01). There were no differences between the SRNS group and SSNS in relapse. Analysis of urinary N-acetyl-β-d-glucosaminidase (U-NAG) by colorimetric assay showed significantly higher values in the SRNS group of patients than in SDNS, SSNS, and control groups. A positive correlation between U-NAG and proteinuria was demonstrated (r=0. 73, P<0.01). The SRNS group of patients (n=12, 11 with a histologic diagnosis of FSGS and one with diffuse mesangial proliferation) was treated with the same protocol of i.v. methylprednisone and oral cyclophosphamide. Long-term follow-up showed a progressive decrease in U-β₂M and U-NAG excretion to control values in the 3rd year, except in one patient who did not respond to the treatment. In the FSGS patients, evaluation of the contribution of structural interstitial histological abnormalities, including each of the histological parameters considered in interstitial scarring to the functional tubule abnormalities assessed by β₂M and NAG excretion, was performed by multiple regression analysis. The r ² values for β₂M and NAG were 53.99%, P=0.19, and 57.90%, P=0.14, respectively; neither was significant. We conclude that: (1) proximal tubule cell dysfunction, partially affected by massive albuminuria, may account for the higher values of β₂M and NAG excretion in the SRNS patients and (2) urine β₂M and NAG levels are not helpful in identifying histological evidence of structural tubulointerstitial damage in children with steroid-resistant nephrotic syndrome. Received: 28 December 1999 / Revised: 20 July 2000 / Accepted: 21 July 2000     

NGAL distinguishes steroid sensitivity in idiopathic nephrotic syndrome

Background

Idiopathic nephrotic syndrome (NS) is the most common glomerular disorder of childhood. Invasive biopsy remains the diagnostic method of choice for NS. Prognosis correlates with steroid responsiveness, from sensitive (SSNS) to resistant (SRNS). Neutrophil gelatinase-associated lipocalin (NGAL) has been demonstrated to be a powerful risk marker of chronic kidney disease progression. We set out to determine if urine NGAL can distinguish between patients with SRNS, SSNS, and healthy controls.

Methods

Urine and clinical data were collected from patients at Cincinnati Children's Hospital who were recently diagnosed with active nephrotic syndrome as well as healthy controls. Participants included SRNS (n?=?15), SSNS (n?=?14), and healthy controls (n?=?10). Urinary NGAL was measured by ELISA and normalized to creatinine.

Results

Median NGAL was significantly (p?p?r?=??0.5, p?

Conclusions

NGAL levels differentiate SSNS from SRNS and correlate with disease severity in SRNS.

     

The differential diagnostic value of urinary enzyme and amino acid excretion in children with nephrotic syndrome

Urinary enzymesN-acetyl--d-glucosaminidase (NAG) and -glutamyl transpeptidase (-GT) are sensitive markers of specific renal cell damage. Excessive urinary amino acid excretion may also be an indicator of renal tubular damage. We have evaluated urinary excretion of NAG,-GT and 37 amino acids, phospholipids and dipeptides in 30 children (aged 2.3–18.1 years) with nephrotic syndrome (NS), 23 with minimal change nephrotic syndrome (MCNS), 7 with focal segmental glomerulosclerosis (FSGS) and 16 healthy age-matched controls. Nine MCNS patients were in relapse and 14 in remission. Enzyme activity is expressed as micromoles per milligram urinary creatinine. In FSGS, NAG excretion correlated with the following: blood urea nitrogen (BUN) (r=0.8), serum protein (r=0.57), serum cholesterol (r=0.85), serum albumin (r=–0.68) and proteinuria (r=0.56). In FSGS the -GT excretion was not significantly different from MCNS in remission or in relapse. In FSGS, -GT excretion correlated with the following: BUN (r=0.48), serum creatinine (r=–0.66), serum protein (r=–0.54), serum albumin (r=–0.68) and serum cholesterol (r=0.87). Compared with controls, the urinary excretion of 5 amino acids was increased in FSGS patients as a possible indicator of tubular damage. The value for 7 amino acids was reduced in MCNS patients. Urinary amino acid excretion was not different from controls for the other amino acids in either FSGS or MCNS. These data suggest that urinary enzyme excretion, particularly NAG excretion, and amino acid excretion may be useful in the diagnosis and degree of disease in these histological forms of NS in children.Crippled Childrens Foundation Research Center     

Glycosaminoglycan excretion in children with nephrotic syndrome

Although most childhood nephrotic syndromes respond to steroid treatment, steroid resistant nephrotic syndrome (SRNS) is also common and is particularly difficult to treat. This study investigated the role of glycosaminoglycans (GAG) in the pathogenesis and clinical course of nephrotic syndrome in children. Thirty-four children (21 males and 13 females, mean age 3.7±1.6 years) with steroid-sensitive nephrotic syndrome and 20 children with steroid-resistant nephrotic syndrome (12 males and 8 females, mean age 10.9±3.8 years; of the twenty, four had primary SRNS (FSGS) and the others had secondary SRNS) were included the study. Mean urine levels of GAG relative to creatinine (U_GAG/U_Cr) in patients with SRNS (n=20, 113.01±78.46 mg g^–1 Cr) and in patients experiencing the nephrotic period of steroid-sensitive nephrotic syndrome (n=34, 132.15±101.55 mg g^–1 Cr) were both significantly higher than mean U_GAG/U_Cr for control subjects (n=30, 51.83±47.66 mg g^–1 Cr) (P<0.01 for both). Patients excreted significantly more GAG during the nephrotic period of steroid-sensitive nephrotic syndrome than during remission (132.15±101.55 vs 39.11±42.73 mg g^–1 Cr, respectively; P<0.01). There was, however, no significant difference between U_GAG/U_Cr for patients with steroid-resistant nephrotic syndrome and U_GAG/U_Cr in the nephrotic period of steroid-sensitive nephrotic syndrome. Urine GAG excretion correlated significantly with the severity of proteinuria. The results suggest that GAG play a significant role in the pathogenesis of nephrotic syndrome but that GAG excretion is not a marker for response to steroid treatment in pediatric patients with this condition.     

Effect of galactose on glomerular permeability and proteinuria in steroid-resistant nephrotic syndrome

Background

Idiopathic steroid-resistant nephrotic syndrome (SRNS) has been associated with the presence of a circulating focal sclerosis permeability factor (FSPF) thought to damage the glomerular barrier and increase permeability to albumin. Galactose binds and inactivates FSPF in vitro, but its effect in vivo is uncertain.

Methods

A prospective clinical trial was conducted to investigate the effect of oral galactose on FSPF and proteinuria in children with SRNS. Seven pediatric subjects with idiopathic SRNS and positive FSPF activity (>0.5) were treated with oral galactose (0.2 gm/kg/dose twice daily) for 16 weeks. Post-treatment FSPF and proteinuria were measured.

Results

Focal sclerosis permeability factor activity of the seven subjects decreased from 0.69?±?0.11 to 0.35?±?0.21 (p?=?0.009) in response to galactose. The two subjects with post-transplant recurrence of focal segmental glomerulosclerosis (FSGS) demonstrated the most significant improvement in FSPF (p?=?0.006). Despite this decrease in FSPF, the pre- and post-treatment urine protein:creatinine ratio remained unchanged and no subject achieved remission.

Conclusions

Galactose decreases FSPF in children with SRNS, with the most significant improvement in those with post-transplant FSGS recurrence, but it fails to improve proteinuria. At the present time there is no evidence to support the use of galactose in children with FSGS, either pre- or post-transplant. Future studies to investigate the role of galactose as preemptive therapy to decrease the risk of post-transplant FSGS recurrence may be useful.     

High serum adiponectin concentration in children with chronic kidney disease

Adiponectin (ADPN) counteracts the inflammatory response of the endothelium, which plays an important role in the development of atherosclerosis in patients with chronic kidney disease (CKD). Data in children with CKD are scarce. We examined serum ADPN concentration in 90 children with various renal disorders: 28 with CKD on conservative treatment (CKD), 21 on regular dialysis treatment (D), and 41 after kidney transplantation (Tx); 27 age-matched healthy children served as controls (C). Body mass index (BMI), estimated glomerular filtration rate (eGFR), lipids, homocysteine, high sensitivity CRP (hsCRP), and systolic blood pressure (SBP) were also measured. Mean serum ADPN concentration was significantly higher in patients with CKD (27.3 μg/ml ±15.0), on D (34.2 μg/ml ±14.9), and after Tx (23.6 μg/ml ±9.5) compared with ADPN levels in C (13.5 μg/ml ±6.1) (p < 0.0001). Serum ADPN concentration was inversely related to BMI (p = 0.001) and SBP (p = 0.004). In the multiple linear regression analysis, only SBP remained independently associated with ADPN plasma levels. Data show that children with CKD have significantly higher serum ADPN, even after Tx. The protective antiarthrosclerotic effect of ADPN may be mediated by lower SBP, a finding that deserves further study.     

Adiponectin is markedly increased in patients with nephrotic syndrome and is related to metabolic risk factors

BACKGROUND: Adiponectin (ADPN), the gene product of apM1, is the most abundant secretory protein of the adipose tissue in human plasma. Altered regulation (reduced synthesis) of this substance may be relevant to endothelial dysfunction and cardiovascular complications in patients with ESRD. METHODS: We investigated the relationship between plasma ADPN, glomerular filtration rate (GFR) (plasma iohexol clearance), and metabolic risk factors in 16 patients with nephrotic syndrome, in 25 patients with chronic nephropathies without nephrotic syndrome, and in 31 healthy subjects. RESULTS: Plasma ADPN was much higher (P < 0.01) in patients with nephrotic syndrome (24.4 +/- 14.9 microg/mL) than in patients with chronic nephropathies without nephrotic syndrome (12.3 +/- 7.2 microg/mL) and healthy subjects (5.9 +/- 2.6 microg/mL). In the aggregate 24-hour, proteinuria (r = 0.53, P < 0.01) and serum cholesterol (r = 0.53, P < 0.01) were strong and direct correlates of plasma ADPN, while serum albumin correlated inversely (r = -0.46, P < 0.01) with this protein. Proteinuria appeared to be an important confounder of the relationship between ADPN and the GFR because in the whole patient population (with and without nephrotic syndrome), this relationship emerged only after data adjustment for 24-hour proteinuria (partial r = -0.31, P = 0.05), while no such relationship was demonstrable on crude data analysis (r = 0.03, P = 0.87). CONCLUSIONS: ADPN is markedly increased in patients with nephrotic syndrome, and proteinuria is strongly related to circulating ADPN in patients with nephrotic and non-nephrotic renal diseases. The relationships between plasma ADPN, serum cholesterol, and serum albumin suggest that this adipocyte protein may serve to mitigate endothelial damage triggered by dyslipidemia and other risk factors in patients with chronic renal diseases.     

Pharmacokinetics of rituximab in a pediatric patient with therapy-resistant nephrotic syndrome

Background

Rituximab (RTX) has recently been introduced as a second-line therapy for nephrotic syndrome in children. Studies show that RTX given during the nephrotic state may be less effective than treatment during a non-nephrotic state, possibly due to loss of RTX in the urine.

Case-Diagnosis/Treatment

We describe a 10-year-old boy with steroid-resistant nephrotic syndrome (SRNS) treated with RTX during a phase of active non-selective proteinuria. The serum half-life of RTX in this patient was less than 1 day compared to 20 days in patients without protein losses. Urinary clearance was at least 25 %, compared to approximately 0 % in control patients. However, RTX loss in the urine, as well as in pleural effusion and ascites, only partly explains the rapid drop in the serum RTX concentration of this patient.

Conclusions

Serum half-life of RTX can be extremely short, partly due to excessive urinary losses in therapy-resistant nephrotic syndrome with non-selective proteinuria, as seen in our patient. These findings may help to explain the poor results of RTX treatment in patients with active proteinuria.

     

Serum neutrophil gelatinase-associated lipocalin as a marker of renal function in children with chronic kidney disease

Very few biomarkers exist for monitoring chronic kidney disease (CKD). We have recently shown that serum neutrophil gelatinase-associated lipocalin (NGAL) represents a novel biomarker for early identification of acute kidney injury. In this study, we hypothesized that serum NGAL may also represent a biomarker for the quantitation of CKD. Forty-five children with CKD stages 2–4 were prospectively recruited for measurement of serum NGAL, serum cystatin C, glomerular filtration rate (GFR) by Ioversol clearance, and estimated GFR (eGFR) by Schwartz formula. Serum NGAL significantly correlated with cystatin C (r=0.74, P<0.000). Both NGAL and cystatin C significantly correlated with measured GFR (r=0.62, P<0.000; and r=0.71, P<0.000, respectively) as well as with eGFR (r=0.66, P<0.000 and r=0.59, P<0.000, respectively). At GFR levels of ≥30 ml/min per 1.73 m², serum NGAL, cystatin C, and eGFR were all significantly correlated with measured GFR. However, in subjects with lower GFRs (<30 ml/min per 1.73 m²), serum NGAL levels correlated best with measured GFR (r=0.62), followed by cystatin C (r=0.41). We conclude that (a) both serum NGAL and cystatin C may prove useful in the quantitation of CKD, and (b) by correlation analysis, NGAL outperforms cystatin C and eGFR at lower levels of measured GFR.     

NGAL and NT-proBNP levels in diabetic patients with macroproteinuria

Abstract

Background: In patients with heart failure plasma N-terminal pro-brain natriuretic peptide (NT-proBNP) levels are correlated to urine neutrophil gelatinase-associated lipocalin (NGAL) levels. We prospectively evaluated the relationship among glomerular filtration rate (eGFR), urine albumin-to-creatinine ratio (ACR), urine and serum NGAL and NT-proBNP levels in 20 type II diabetic patients with macroalbuminuria at 4-month intervals. Results: Compared with 20 age, gender-matched healthy controls, diabetic patients had higher urine and serum NGAL, serum NT-proBNP and lower eGFR. The eGFR of the patients at the baseline, the 4th and the 8th month were 29.6?±?12.0, 27.8?±?13.7 and 22.9?±?10.4?mL/min/1.73?m², respectively. No significant change in urine NGAL levels was detected (p?>?0.05), whereas there were significant increases in NT-proBNP, serum NGAL and urine ACR and significant decrease in eGFR as the study progressed (p?<?0.05). Both the baseline and the 4th month urine ACR were positively correlated to NT-proBNP levels measured at the same periods (r: 0.451; p: 0.046; r: 0.489; p: 0.029 respectively). In all measurements, urine ACR was negatively correlated to serum albumin levels measured at the same periods (r: ?0.792; p: 0.000; r: ?0.716; p: 0.000; r: ?0.531; p: 0.016 respectively). None of eGFR measurements was correlated with NT-proBNP (p?>?0.05). Neither serum NGAL nor urinary NGAL levels are associated with NT-proBNP (p?>?0.05). Conclusion: Our findings show an association between NT-proBNP and proteinuria in type II diabetic patients with macroalbuminuria but not with serum and urine NGAL.     

Subclinical non-autoimmune hypothyroidism in children with steroid resistant nephrotic syndrome

Background

Thyroid status has not been studied well in children with steroid resistant nephrotic syndrome (SRNS).

Methods

In this cross sectional study we recruited 20 children aged 1–16 years with SRNS and similar number of controls. Serum levels of FT3, FT4 and TSH were measured in all the subjects. Overt hypothyroidism was defined as low FT4 (normal values: 0.7–2.0 ng/mL) and elevated serum TSH above reference values (0.45–4.5 mIU/L). Subclinical hypothyroidism (SH) was defined as an elevation in serum TSH with a normal serum FT4 concentration. The primary outcome measure was serum levels of FT3, FT4 and TSH in children with SRNS.

Results

Thirty per cent of the children (n = 6) with SRNS had non-autoimmune subclinical hypothyroidism (2 children each with grade I, II and III). Children with SRNS had a median TSH value [3.9 mIU/L (0.5–13)] within normal range, but levels were high as compared to controls. Out of 6 children with SH, 3 were in partial remission, 3 were in complete remission. The TSH levels normalized on thyroxine supplementation in grades II and III subclinical hypothyroidism.

Conclusion

Subclinical non-autoimmune hypothyroidism is present in a significant proportion of children with SRNS despite partial or complete remission. Thyroid profile should be evaluated routinely in this subset of patients.     

Treatment of the childhood haemolytic uraemic syndrome with plasma

Seventy-nine children with haemolytic uraemic syndrome (mean age 28 months) were randomly assigned either to a group receiving plasma infusions (plasma group,n=39) or to a group treated conservatively (control group,n=40). The duration of haemolysis, thrombocytopenia and anuria was similar in the two groups. Serum creatinine levels were similar in the two groups at the 1-month follow-up but were higher in the control group at 3 months (plasma group 49±14, control group 66±28 mol/l;P<0.02) and at 6 months (plasma group 48±13, control group 63±21 mol/l;P<0.005). The prevalence of proteinuria was also higher in the control group at the 6-month follow-up (plasma group 17%, control group 46%;P<0.02). However differences were no longer significant after 1 year. Renal tissue was examined in 54 cases (plasma group,n=27; control group,n=27). Diffuse cortical necrosis was present in 7 cases in the control group but was absent in the plasma group (P<0.02). Taking into consideration the higher serum creatinine levels, the higher prevalence of proteinuria during the first 6 months of follow-up in the control group and the presence of diffuse cortical necrosis in this group compared with the plasma group, we conclude that plasma infusions should be regarded as beneficial. Further study is needed to determine which plasma fraction is involved.     

Testicular tissue nitric oxide and thiobarbituric acid reactive substance levels: evaluation with respect to the pathogenesis of varicocele

The aim of the present study is to evaluate tissue nitric oxide (NO) and thiobarbituric acid reactive substance (TBARS) levels in testicular tissue, and to determine their relationship with seminal parameters in order to explain possible effects on varicocele pathophysiology.Ten adult male Wistar rats at 8 weeks old underwent partial left renal vein ligation. A sham operation was performed on control rats in a second group of another ten rats. All animals were killed 4 weeks after surgery. The testes were removed and histological changes were observed by light microscopy with haematoxylin and eosin stain on half of each testis. The rest of testis was used for the evaluation of testicular tissue NO and TBARS levels. Epididymal aspirated seminal plasma was used for semen analysis and morphological analysis was carried out according to Krugers criteria. Statistical analysis was performed by using Mann-Whitney U-tests and Spearman rank correlations between the two groups for NO and TBARS levels and for seminal parameters. Testicular tissue NO and TBARS levels (mean±SEM) were 62.8±10.1 mol/g protein and 4.7±0.3 nmol/g protein in group 1. These parameters were 16.9±2.2 mol/g protein and 3.1±0.2 nmol/g protein in the group 2 controls. There were significant differences between these parameters (P_NO=0.000, P_TBARS=0.001). Although a positive and significant correlation between testicular tissue NO and TBARS levels was found (r_s=0.739, P=0.014), there was only a strong negative correlation between NO levels and sperm motility in group 1 (r_s=–0.815, P=0.004). We found that this effect of NO on sperm motility was independent from TBARS levels after regression analysis (r²=-0.687, =0.825, P=0.034). Although there were statistically significant differences in seminal parameters between the two groups, there was no difference between them in the histopathological examination. We found that sperm motility was significantly related to testicular tissue NO levels only. Thus, we suggest that NO is an important mediator in the pathogenesis of varicocele. TBARS and other substances have been effective via NO pathways.     

Positive C1q staining associated with poor renal outcome in membranoproliferative glomerulonephritis

Background

Pathogenesis and clinical prognosis of membranoproliferative glomerulonephritis (MPGN) has not yet been established.

Methods

We conducted a retrospective study of 41 patients with MPGN (type I and III) and examined the renal survival. In addition, factors contributing to survival time were analyzed.

Results

Fourteen patients (34 %) were classified into the renal death group. Patients with nephrotic syndrome and positive C1q staining of glomerular deposits showed a particularly poor prognosis. Significantly higher frequency of nephrotic syndrome and higher urinary protein excretion were observed in the renal death group (p = 0.0002, p = 0.0002) than in the renal survival group. The intensity of C1q staining was positively correlated with the severity of the proteinuria (p = 0.004). Factors that influenced the survival time were positive C1q staining of glomerular deposits (p = 0.003), presence of nephrotic syndrome (p = 0.004), serum albumin (p = 0.02), and proteinuria (p = 0.04).

Conclusions

C1q staining in glomerular deposits and nephrotic syndrome were important factors influencing the prognosis and outcome in MPGN patients. C1q deposition may play a key role in the pathogenesis of MPGN, as evidenced by numerous observations, such as induction of proteinuria.     

Unknown aspect of the old disease: does dyslipidemia in systemic AA amyloidosis differ from the dyslipidemia in primary glomerulonephritis?

Abstract

Aim: To investigate the nature of dyslipidemia and its diversity in patients with systemic AA amyloidosis. Methods: The reports of the kidney biopsies performed due to nephrotic proteinuria (>3.5?g/day/1.73?m²) with preserved renal function [glomerular filtration rate (GFR) >60?mL/min/1.73?m²] were reviewed. Clinical and laboratory data of the patients with systemic AA amyloidosis and primary glomerulonephritis (PG) were analyzed. Results: A total of 104 (systemic AA amyloidosis: 43, PG: 61) patients were included in the study. Proteinuria and GFR levels were similar in both the groups. Patients with systemic AA amyloidosis group had lower serum albumin (p?=?0.002), lower hemoglobin levels (p?=?0.001), higher platelet counts (p?=?0.002) and higher C-reactive protein levels (p?=?0.001) compared to patients in PG group. Although the frequency of dyslipidemia was similar in the groups (86.0 vs. 93.4%), patients with systemic amyloidosis had both lower values of LDL-C (4.56?±?2.05 vs. 5.49?±?2.23?mmol/L, p?=?0.028) and HDL-C (1.19?±?0.36 vs. 1.35?±?0.39?mmol/L, p?=?0.035). Serum lipid levels were correlated with serum total protein, albumin and proteinuria levels in PG group. However, in the systemic amyloidosis group, only one clear correlation between serum lipid and hemoglobin levels was estimated. A multivariate analysis demonstrated that LDL-C was independently associated with the etiology of nephrotic proteinuria, serum total protein, serum albumin (inversely) and hemoglobin levels. Conclusions: Although dyslipidemia is closely associated with serum total protein, albumin and proteinuria in patients with PG, there is no clear such association in patients with systemic amyloidosis. Correlation between serum lipid and hemoglobin levels in this group and other findings point out that probably complex mechanisms take place in dyslipidemia of nephrotic syndrome caused by systemic AA amyloidosis.