Glomerular proteinuria as an early sign of renal-transplant rejection

The introduction of cyclosporin gave rise to an additional problem in the surveillance of renal transplant patients, namely the differentiation between cyclosporin toxicity and acute transplant rejection. The development of assays for specific proteins in urine has produced a non-invasive solution to this problem. In 55 renal transplant patients the following proteins were determined daily in 24 h-urine samples: IgG, transferrin (TF), albumin, beta 2-microglobulin (beta 2-MG), retinol binding protein (RBP), alpha 1-microglobulin (alpha 1-MG) and alpha 1-antitrypsin (alpha 1-AT). All proteins were determined quantitatively using immunoluminometric assays and 10 microliters urine in dilutions from 1:1-1:100. The urinary protein excretion was related to the actual creatinine clearance as this index gave the best differentiation between normal and abnormal status. In 24 h-urine, intraindividual peaks of IgG, TF and albumin were seen regularly in acute rejection episodes. However, a peak in the "tubular" proteins (RBP, beta 2-MG, alpha 1-MG) could not be detected. After effective treatment of the rejection episode, the renal function improved and the protein excretion returned to prerejection episode levels. In bacterial infection of the urogenital tract, urinary alpha1-AT levels rose. They returned to normal after successful antibiotic treatment. In two cases of cyclosporin toxicity neither glomerular nor tubular proteins were excreted in abnormal amounts when compared with transplant patients without complications, the only changes being an increase in serum creatinine as a result of reduced renal function.     

Human alpha 1-microglobulin and its relationship to renal function

To evaluate the clinical usefulness in terms of estimation for glomerular filtration rate (GFR), we determined the levels of alpha 1-microglobulin (alpha 1m) in the serum and urine of patients with various renal diseases and compared with those of beta 2-microglobulin (beta 2m) and creatinine. Serum and urinary alpha 1m levels were measured by using single-radial immunodiffusion method. 24-hour creatinine clearance (Ccr) was used as a indicator of GFR. There was a significant positive correlation between serum alpha 1m and creatinine levels (r = 0.75, p less than 0.001). Serum alpha 1m, beta 2m and creatinine inversely correlated and logarithmically correlated to Ccr as shown in the following equations: log alpha 1m = 2.30 - 0.42 X log Ccr (r = -0.74); log beta 2m = 2.06 - 0.91 X log Ccr (r = -0.92); log creatinine = 1.57 - 0.78 X log Ccr (r = -0.94). Both correlation coefficient and regression coefficient for alpha 1m were rather poor compared to those for beta 2m and creatinine. However, alpha 1m levels started to increase over normal range when Ccr fell below 80 liters/day, while beta 2m and creatinine remained within normal ranges. The daily urinary excretion of alpha 1m was increased in the patients whose Ccr was within normal limits compared to that of healthy control subjects (15.2 +/- 3.2 mg/day, n = 19, vs. 5.7 +/- 0.7, n = 7, p less than 0.001). Fractional clearance of alpha 1m increased proportionally to the decrease of Ccr. These data suggest that combined measurements of alpha 1m in the serum and urine seem to be useful to estimate GFR, especially to detect the mild reduction of CFR.     

Effects of combination chemotherapy with cis-diamminedichloroplatinum (II) (CDDP) on renal function in patients with urogenital malignancies

The renal function in 23 patients with advanced urogenital cancers (10 testicular, 8 uroepithelial, 3 prostatic cancers and 1 penile cancer) treated with a total of 3 or 4 cycles of combination chemotherapy including CDDP was examined prospectively, by measuring of creatinine clearance (Ccr), fractional excretion of beta 2 microglobulin (FE beta 2 MG) and urinary N-acetyl-beta-glucosaminidase (NAG). Patients with testicular cancers (group 1) who received the cumulative CDDP dose of 360-1966 mg (on average 868 mg), the decrease in Ccr and increase in FE beta 2 MG and NAG were temporary during each chemotherapy cycle. However, in the overall course, after the cumulative dose exceeded 600 mg, higher beta 2 MG excretion persisted and after the cumulative dose exceeded 800 mg, Ccr decreased to 30% of the pretreatment level. This suggests cumulative delayed, irreversible renal damage. The severity of decrease in Ccr paralleled the increase in cumulative CDDP dose. Patients with urogenital cancers other than testicular cancer (group 2) who received the cumulative CDDP dose of 80-480 mg (on average 217 mg), and who had decreased Ccr and tubular damage prior to treatment, even though the cumulative dose was lower than in group 1, changes in Ccr, FE beta 2 MG and NAG were almost in the same magnitude as in group 1. Determination of NAG is useful for detection of the early change in the tubules several days after CDDP administration, while that of beta 2 MG is useful for detection of the chronic damage of renal tubules after several cycles of CDDP chemotherapy. CDDP nephrotoxicity is characterized by dose-dependent tubular damage. Although renal injury may not be evident during the early course of treatment, repeated courses of CDDP may lead to clinically serious chronic renal failure.     

Study on urinary low molecular protein and enzyme in primary vesico-ureteral reflux patients

Urinary beta-2-microglobulin (beta 2-MG), urinary N-acetyl-beta-D-glucosaminidase (NAG), urinary creatinine (Cr) and serum creatinine level were measured in 79 patients with primary vesico-ureteral reflux. Comparing the data between conservatively treated group and operated group, between pre and post operation, we obtained the following conclusions: 1. From urinary beta 2-MG and NAG, renal tubular damage tended to increase in both conservatively treated group and operated group in proportion to the grade of reflux. But the degree of tubular damage was more severe in the conservatively treated group than in the operated group. 2. Tubular reabsorption ability was lower in the operated group than in the conservatively treated group. 3. In patients with severe tubular damage, improvement of tubular function was seen at the early stage after operation. 4. Anti-reflux operation was shown to be effective even in improving glomerular function.     

Evaluation of renal function in children with primary VUR up to two years old

The function of 99 refluxing kidneys of 61 children up to two years old at the time of diagnosis was evaluated by 99mTc-DMSA renoscintigraphy, urinary beta 2-microglobulin (beta 2-MG), alpha 1-microglobulin (alpha 1-MG) and N-acetyl-beta-D-glucosamidase (NAG). High grade reflex (grade IV, V) was found in 45% of the cases. 76%, 51% and 92% of the cases showed abnormally high value of urinary beta 2-MG, alpha 1-MG and NAG, respectively. These results indicate that they have already had tubular dysfunction at the time of diagnosis. DMSA renoscintigraphy of 82 refluxing kidneys of 49 children was performed. Of these, 48% had renal scar and 28% had serious renal dysfunction [DMSA uptake rate less than 18%]. 10-20% of low grade VUR had less than 18% DMSA uptake rate. Two patterns were noticed in the group in which urinary beta 2-MG ranged 0.33-1.0. One was characterized by good bilateral renal function with slight tubular damage and the other serious renal dysfunction with fixed tubular damage. No remarkable recovery of the renal function was noticed after antireflux operation in the second pattern cases. In many cases, in which urinary beta 2-MG was more than 1.0, improvement of DMSA uptake rate was noticed after antireflux operation.     

Plasma and urinary cytokine homeostasis and renal dysfunction during cardiac surgery

BACKGROUND: Cardiac surgery induces changes in plasma cytokines. Proinflammatory cytokines have been associated with a number of renal diseases. The proinflammatory cytokines interleukin 8 (IL-8), tumor necrosis factor alpha (TNFalpha), and interleukin 1beta (IL-1beta) are smaller than the antiinflammatory cytokines interleukin 10 (IL-10), interleukin 1 receptor antagonist (IL-1ra), and TNF soluble receptor 2 (TNFsr2), and thus undergo glomerular filtration more readily. Accordingly, this study investigated the relation between plasma and urinary cytokines and proximal renal dysfunction during cardiac surgery. METHODS: Twenty patients undergoing coronary artery bypass grafting with cardiopulmonary bypass (CPB) were studied. Blood and urine samples were analyzed for proinflammatory and antiinflammatory cytokines. Proximal tubular dysfunction was measured using urinary N-acetyl-beta-d-glucosaminidase (NAG)/creatinine and alpha1-microglobulin/creatinine ratios. RESULTS: Plasma IL-8, IL-10, IL-1ra, and TNFsr2 values were significantly elevated compared with baseline. Urinary IL-1ra and TNFsr2 were significantly elevated. Urinary NAG/creatinine and alpha1-microglobulin/creatinine ratios were also elevated. Plasma TNFalpha at 2 h correlated with urinary NAG/creatinine ratio at 2 and 6 h (P < 0.05) and with urinary IL-1ra at 2 h (P < 0.05). Plasma IL-8 at 2 h correlated with NAG/creatinine at 6 h (P < 0.05). Urinary IL-1ra correlated with urinary NAG/creatinine ratio after cross-clamp release and 2 and 6 h after CPB (P < 0.05). CONCLUSIONS: Cardiac surgery using CPB leads to changes in plasma and urinary cytokine homeostasis that correlate with renal proximal tubular dysfunction. This dysfunction may be related to the renal filtration of proinflammatory mediators. Renal autoprotective mechanisms may involve the intrarenal generation of antiinflammatory cytokines.     

Renal tubular impairment in traumatized patients

Urinary beta 2-microglobulin (beta 2M) and N-acetyl-beta-D-glucosaminidase (NAG) in addition to conventional renal parameters such as creatinine clearance (Ccr), free water clearance (CH2O) and fractional excretion of sodium (FENa) were measured in 79 traumatized patients. These patients were separated into two groups, one with shock on admission (N = 43). In patients with shock, CH2O, FENa and urinary excretion of Beta 2M and NAG indicated abnormal levels correlating with impairment of Ccr, inspite of adequate urine output, on the day of trauma. Even in patients without shock, urinary Beta 2M and/or NAG increased without impairment of urine output, Ccr, CH2O and FENa, and did not return to normal level during the following 7 days. The results suggest a liability to damage and the delayed improvement of renal tubulus in traumatized patients.     

Early tubular proteinuria and the development of nephritis in Henoch-Schönlein purpura

The prognosis of Henoch-Schonlein purpura (HSP) is mainly determined by the involvement of the kidney, but prognostic markers have not been established. To study the extent of tubular involvement in HSP and its relationship to the development of HSP nephritis, we measured the urinary excretion of two tubular marker proteins in 36 children with HSP. After admission, urinary N-acetyl-beta-D-glucosaminidase (NAG) was determined in 20 children and alpha1-microglobulin (alpha1-MG) in 16 children respectively. These values were compared with the biochemical data on admission, 1 month, 6 months, and 12 months later. A total of 198 24-h urine samples from healthy children were used for the establishment of reference data for NAG and alpha1-MG (mean+/-2 SD). Twenty-one patients had elevated excretion of either NAG (>mean+2 SD, n=12) or alpha1-MG (>mean+2 SD, n=9). The highest values (>mean+4 SD) were found in patients with early kidney involvement. Normal values were accompanied by a benign further clinical course. Children with intermediate high values (>mean+2 SD, 相似文献   

Evaluation of renal function and prediction of renal functional recovery in children with unilateral hydronephrosis using renal pelvic urine]

In 29 children with unilateral hydronephrosis who underwent surgery at the age from 2 months to 15 years (27 patients with ureteropelvic junction stenosis and 2 with obstructive megaureter), beta 2-microglobulin (beta 2-MG), alpha 1-microglobulin (alpha 1-MG), N-acetyl-beta-D-glucosaminidase (NAG) and albumin were determined in renal pelvic urine from the hydronephrotic kidney to evaluate renal dysfunction accompanying urinary tract obstruction. Moreover, it was also examined whether it is possible to predict functional recovery of the hydronephrotic kidney on the basis of relation between these indices and pre- and postoperative changes in renal dimercaptosuccinic acid (DMSA) uptake rate. The values of beta 2-MG, alpha 1-MG, NAG and albumin in urine from the renal pelvis were high in 48%, 50%, 75% and 83% of the patients, respectively. Among the patients of one year and up, those with low preoperative DMSA uptake rate tended to have high values of beta 2-MG, alpha 1-MG and NAG. On the contrary, albumin level was high in 78% of patients who had good preoperative DMSA uptake rate. With respect to the relation between pre- and postoperative changes in DMSA uptake rate and each index, beta 2-MG and alpha 1-MG were high in 73% and 62% of patients who exhibited a marked increase in postoperative DMSA uptake rate. In patients without a remarkable change in DMSA uptake rate before and after surgery, on the other hand, the values of these were high only in 25% and 36%.(ABSTRACT TRUNCATED AT 250 WORDS)     

Plasma and Urinary Cytokine Homeostasis and Renal Dysfunction during Cardiac Surgery

Background: Cardiac surgery induces changes in plasma cytokines. Proinflammatory cytokines have been associated with a number of renal diseases. The proinflammatory cytokines interleukin 8 (IL-8), tumor necrosis factor [alpha] (TNF[alpha]), and interleukin 1[beta] (IL-1[beta]) are smaller than the antiinflammatory cytokines interleukin 10 (IL-10), interleukin 1 receptor antagonist (IL-1ra), and TNF soluble receptor 2 (TNFsr2), and thus undergo glomerular filtration more readily. Accordingly, this study investigated the relation between plasma and urinary cytokines and proximal renal dysfunction during cardiac surgery.

Methods: Twenty patients undergoing coronary artery bypass grafting with cardiopulmonary bypass (CPB) were studied. Blood and urine samples were analyzed for proinflammatory and antiinflammatory cytokines. Proximal tubular dysfunction was measured using urinary N-acetyl-[beta]-d-glucosaminidase (NAG)/creatinine and [alpha]1-microglobulin/creatinine ratios.

Results: Plasma IL-8, IL-10, IL-1ra, and TNFsr2 values were significantly elevated compared with baseline. Urinary IL-1ra and TNFsr2 were significantly elevated. Urinary NAG/creatinine and [alpha]1-microglobulin/creatinine ratios were also elevated. Plasma TNF[alpha] at 2 h correlated with urinary NAG/creatinine ratio at 2 and 6 h (P < 0.05) and with urinary IL-1ra at 2 h (P < 0.05). Plasma IL-8 at 2 h correlated with NAG/creatinine at 6 h (P < 0.05). Urinary IL-1ra correlated with urinary NAG/creatinine ratio after cross-clamp release and 2 and 6 h after CPB (P < 0.05).     

Study on urinary splitting enzymes and proteins. III. Effect of non-ionic contrast medium on renal function

Renal toxicity of non-ionic contrast medium (iohexol) for drip infused pyelography (DIP) was studied in a randomized trial of nine patients with normal renal function. Urine samples were collected before and immediately after DIP, and analyzed for albumin, an index of glomerular permeability; gamma-glutamyl transpeptidase (gamma-GTP), a brush-border enzyme; N-acetyl-beta-glucosaminidase (NAG), a lysosomal enzyme; alpha 1 microglobulin (alpha 1MG) and beta 2 microglobulin (beta 2MG), an index to tubular proteinuria; and creatinine. The urinary excretion of enzymes and proteins was compared with urinary creatinine. Urinary excretion of gamma-GTP and NAG increased significantly (P less than 0.001, 0.02) after DIP. Urinary alpha 1 MG and beta 2-MG did not change significantly. The change of urinary albumin was mild. Our data suggest that non-ionic, low osmolal radiocontrast medium ioheol shows a lower renal tubular toxicity, and the brush-border enzyme gamma-GTP and lysosomal enzyme NAG are considered as a good index for renal tubular damage.     

Studies of enzymuria and proteinuria: Report 2; Relationship between glomerular filtration rate and urinary enzymuria and proteinuria

Urinary splitting enzymes and proteins including N-acetyl-b-D-glucosanimidase (NAG), beta 2 microglobulin (beta 2MG), and alpha 1 microglobulin: (alpha 1MG), which are established to be useful in the evaluation of renal dysfunction, especially renal tubular impairment, were measured to determine the extent of renal tubular impairment in relation to the degree of glomerular dysfunction in patients with renal deterioration. In healthy volunteers, urinary NAG, alpha 1MG and beta 2MG levels were 3.5 +/- 1.4 (mean +/- SD) U/g creatinine, 2.5 +/- 2.0 mg/l and 88 +/- 75 micrograms/l, respectively. While serum beta 2MG level (SBMG; microgram/ml) was between 2.0 and 2.9, among the patients with renal dysfunction, NAG, alpha 1MG and BMG levels showed 8.6 +/- 5.5, 9.8 +/- 5.8 and 785 +/- 1,264, respectively, and further elevated to 10.1 +/- 5.0, 16.5 +/- 0.7 and 525 +/- 440, respectively with a SBMG level over 3.0. Thus glomerular function was deteriorated, urinary alpha 1MG level elevated to significantly higher with a parallel to renal dysfunction. In patients with more severe renal dysfunction, the corresponding urinary NAG and alpha 1MG levels became significantly higher. However, urinary beta 2MG level was significantly higher in patients with moderate renal dysfunction compared to healthy volunteers only when SBMG level was more than 2.0. Therefore, it was more valuable to measure urinary alpha 1MG with NAG or beta 2MG at SBMG level of less than 1.9 and to determine urinary NAG and alpha 1MG at greater than 2.0. These results indicated that the measurement of the levels of urinary splitting enzymes and proteins is valuable in the evaluation of proximal tubular impairment, even when the degree of glomerular impairment is minimal.(ABSTRACT TRUNCATED AT 250 WORDS)     

Usefulness of serum cystatin-C as a marker of the renal function: a comparative evaluation with beta 2-microglobulin, alpha 1-microglobulin and creatinine

We evaluated the usefulness of cystatin-C as a marker of renal function. Serum cystatin-C level was measured using latex agglutination tests in 885 patients with various forms of renal disease and 200 healthy subjects. In addition to cystatin-C, serum beta 2-microglobulin, alpha 1-microglobulin and serum creatinine (Scr) were measured concomitantly in the same sample. The serum cystatin-C level inversely correlated more closely with creatinine clearance (Ccr) (r = -0.90) than serum beta 2-microglobulin (r = -0.85), alpha 1-microglobulin (r = -0.74) and Scr (r = -0.78). In patients with mildly impaired renal function (defined as Ccr 71-90 ml/min), a significant increase in cystatin-C level was observed in 24% of patients, whereas elevated beta 2-microglobulin and Scr were seen in 8% and elevated alpha 1-microglobulin was seen in 17%. In patients with normal renal function (defined as Ccr > or = 100 ml/min), increased cystatin-C level was observed in 7% of patients, whereas beta 2-microglobulin was seen in 2%, Scr in 2% and alpha 1-microglobulin in 11%. These data suggest that cystatin-C is a better marker of glomerular filtration than beta 2-microglobulin, alpha 1-microglobulin and Scr. Moreover cystatin-C measurement offers improved clinical sensitivity as a screening test for early renal damage.     

Effect of extracorporeal shock wave lithotripsy on renal function-an experience with the new type piezoelectric lithotripter, Therasonic

Seventeen patients with renal stones and 17 patients with ureteral stones were treated using the newly developed piezoelectric shock wave lithotripter, THERASONIC. To determine the effect of shock wave on renal function, urinary N-acetyl-beta-D-glucosaminidase (NAG) activity, urinary beta 2 microglobulin (BMG) concentration, serum BMG concentration and creatinine clearance (Ccr) were measured. Urinary NAG activity and urinary BMG concentration in renal stone patients were significantly elevated immediately after the treatment and returned to the pretreatment value within 24 hours. Neither serum BMG nor Ccr showed significant change in any of the patients. Therefore, we conclude that the renal tubular damage, which is transient and subtle, is the effect of shock wave lithotripsy using THERASONIC machine.     

Clinical investigation of cis-platinum nephrotoxicity in 244 cases of primary lung cancer]

Cisplatin (CDDP) is used widely in the treatment of a large number of carcinomas. The clinical use of cisplatin, however, can be complicated by myelotoxicity, intestinal toxicity and nephrotoxicity. We reviewed CDDP nephrotoxicity in 244 cases with primary lung cancer retrospectively. The enzyme histochemically localized in proximal tubular cells, N-acetyl-beta-D-glucosaminidase (NAG) and beta 2-microglobulin (BMG), a low molecular weight peptide normally reabsorbed by the renal tubular cells that has been used as an indicator for renal proximal tubular damage, were measured. And fractional excretion of Na (FENa%) and serum magnesium (Mg) levels were also measured before and after CDDP administration serially. The following results were obtained; 1) Over 45% of patients with lung cancer showed transient hyperexcretion of urinary NAG and BMG after CDDP administration. And peak excretion of NAG and BMG appeared to occur within 36 hours after administration of CDDP. 2) Almost all cases with persistent azotemia after CDDP administration showed high values of FENa (%), in spite of gradual normalization of urinary NAG and BMG excretion. 3) Hypomagnesemia was a common complication of CDDP nephrotoxicity that might be caused by a defect in renal Mg reabsorption. CDDP-induced nephrotoxicity seemed to be initiated by an acute, mainly proximal tubular impairment that reflects alterations in excretion of urinary enzymes and low molecular weight protein. In cases with persistent azotemia after CDDP administration depressed renal function might be attributed to the impairment of proximal as well as distal tubular reabsorptive functions.     

Early markers of renal dysfunction in patients with sickle cell/beta-thalassemia

Progressive renal failure is one of the main complications in HbS/beta-thalassemia (HbS/beta-thal). Early identification of patients at high risk of developing renal failure is of great importance as it may allow specific measures to delay the progression of renal damage and thus reduce the incidence of end-stage renal failure and mortality. Early predictors of renal impairment in HbS/beta-thal remain to explore. Within this context, we studied 87 compound HbS/beta-thal patients (36 males/51 females; median age 39 years) and 30 healthy controls. In addition to conventional renal biochemistries we measured serum cystatin-C (Cys-C), urine N-acetyl-beta-D-glucosaminidase (NAG) excretion and serum and urinary beta(2)-microglobulin (beta(2)-M). Cystatin-C, NAG and serum beta(2)-M levels were higher in patients than controls. The incidence of patients with high levels of Cys-C, NAG, and beta(2)-M was 32.1, 74.7, and 70.1% respectively, while only 6.8% of patients had increased serum creatinine levels. Cystatin-C and serum beta(2)-M showed a strong correlation with creatinine clearance and age, while NAG positively correlated with proteinuria. An inverse correlation was also shown between hemoglobin and beta(2)-M, NAG, and Cys-C levels. Seven patients with proteinuria received therapy with angiotensin-converting enzyme (ACE) inhibitors. Changes of poteinuria positively correlated with NAG levels. These results indicate that Cys-C is an accurate marker of renal dysfunction, and urinary NAG excretion can be considered as a reliable index of the tubular toxicity, and possible predictor of proteinuria and eventual renal impairment in HbS/beta-thal patients. Furthermore, NAG measurement may be used for monitoring ACE-inhibitors therapy in HbS/beta-thal patients with proteinuria.     

Evaluation of urinary cystatin C as a marker of renal dysfunction

BACKGROUND: Urinary excretion of some low molecular weight proteins (LMWPs) is used as an indicator of tubular dysfunction, since they are increased by the damage of tubular reabsorption. Although serum cystatin C is known to be a sensitive marker for GFR, the property of urinary cystatin C as a LMWP has not been fully observed. We evaluated the clinical utility of urinary cystatin C. METHODS: Urine samples were collected from 130 patients with various degree of renal dysfunction, 62 healthy subjects, and 2 patients with acute renal failure, one with renal acute renal failure, the other with prerenal acute renal failure. Urine levels of cystatin C, beta2-microglobulin (beta2mG), and alpha1-microglobulin (alpha1mG) were measured by immunonephelometry. Creatinine clearance(Ccr) tests were conducted on 130 patients with renal dysfunction. Creatinine(CRE) was measured by enzyme assay. RESULTS: The daily urinary excretions of cystatin C and alpha1mG were increased significantly in patients with Ccr<30 ml/min(group I), compared to those in patients with 30 < or = Ccr<70 ml/min(II), and Ccr > or = 70ml/min(III). Although the mean daily excretion of beta2mG increased as Ccr decreased, the significant difference was not observed. The rate of increase in the mean value between III and I was extremely high in cystatin C. Fractional excretions of cystatin C and beta2mG calculated in the same groups increased significantly in I compared to II and III. The rate of increase in the mean value was higher in cystatin C. Regression analyses between urine CRE and each three LMWP gave the best correlation coefficient for cystatin C in healthy subjects. While in one patient with renal acute renal failure, the rate of increase in urine cystatin C was higher than that of other LMWPs, in another patient with prerenal acute renal failure, the rate of increase in urine cystatin C was low. CONCLUSIONS: Although details of urinary movement of LMWPs in nephrons have not been clearly elucidated, the urinary cystatin C seems to have distinctive properties, and to be useful for the evaluation of renal injury.     

Effects of extracorporeal shock waves on renal morphology, renal function and blood pressure in rats--follow-up for one year]

Effects of extracorporeal shock waves on renal tissue, renal function, and blood pressure were studied by applying 500 shock waves to both kidneys in 72 female Wistar rats. Six groups, 12 rats in each, were sacrificed on days, 1, 7 and at months 1, 3, 6 and 12 after the procedure, when serum levels of BUN, creatinine, urine levels of beta 2-microglobulin (beta 2-MG), N-acetyl-beta-D-glucosaminidase (NAG), 28-kDa carbindin-D and creatinine clearance (Ccr) were determined. Findings were then compared with those from the control group. In each group, both kidneys were weighed and histologically evaluated. In the treatment group, systolic blood pressure was measured at post-irradiation months 1, 3, 6, 9, and 12; plasma renin activity was studied 6 and 12 months after irradiation to make evaluation in comparison with the control group. In the treatment group, histologically, coagulative necrosis associated with bleeding around the renal tubules and tubular epithelial cell degeneration were marked on day 1, but the glomerulus was kept in relatively good shape. Inflammatory cellular infiltration and interstitial fibrosis were noted on day 7 and the addition of scar formation 1 month after irradiation. Interstitial fibrosis, inflammatory cellular infiltration, scar formation, and tubular epithelial degeneration remained significant even after 12 months. In the treatment group, kidneys weighed significantly more than in the control group from day 1 through month 3, with edema likely accounting for this. However, weight then significantly declined 12 months after irradiation, owing to suspected scarring atrophy.(ABSTRACT TRUNCATED AT 250 WORDS)     

Clinical significance of urinary interleukin-6 in children with reflux nephropathy

PURPOSE: We determined urinary interleukin-6 (IL-6) in children with reflux nephropathy to evaluate the clinical significance of this cytokine in the progression of renal injury. MATERIALS AND METHODS: Enrolled in this study were 34 boys and 32 girls in whom 99mtechnetium dimercapto-succinic acid renal scan showed renal scarring. Vesicoureteral reflux had been corrected surgically at least 3 years before study entry. Urinary IL-6 was determined by enzyme-linked immunosorbent assay using spot urine samples. Simultaneously we measured serum creatinine, beta2-microglobulin, alpha1-microglobulin, urinary alpha1-microglobulin and albumin. In addition, IL-6 expression was assessed by immunohistochemical study in the scarred kidneys of 3 boys and 1 girl who underwent nephrectomy due to severe reflux nephropathy with little function on renal scan. RESULTS: Urinary IL-6 was significantly higher in children with severe bilateral renal scarring than in those with mild scarring and normal controls. Urinary IL-6 correlated significantly with serum alpha1-microglobulin (Spearman test p <0. 03), beta2-microglobulin (p <0.003), creatinine (p <0.02) and urinary albumin (p <0.0001). Histological evaluation revealed that IL-6 was predominantly expressed in the tubules in and adjacent to fibrotic areas. CONCLUSIONS: Our observations indicate that tubular IL-6 may be involved in the pathogenesis of tubulointerstitial injury in reflux nephropathy and urinary IL-6 may be a useful tool for monitoring the progression of reflux nephropathy.     

Beta2-Microglobulin and Alpha1-Microglobulin as Markers of Balkan Endemic Nephropathy,a Worldwide Disease

Background:?Urine beta2-microglobulin (beta2-MG) was mainly used as a tubular marker of Balkan endemic nephropathy (BEN) but recently alpha1-microglobulin (alpha1-MG) was proposed for the diagnosis of BEN. In this study, the potential of urine beta2-MG, alpha1-MG, albumin, and total protein in the differentiation of BEN from healthy persons and patients with glomerulonephritis (GN) and nephrosclerosis (NS) was examined.?Methods:?This study involved 47 patients with BEN, 36 with GN, 11 with NS, 30 healthy subjects from BEN families, and 46 healthy subjects from non-BEN families.?Results:?In BEN patients area under the curve (AUC) for urine beta2-MG (0.828) and alpha1-MG (0.782) was higher than for urine albumin (0.740), but in GN patients AUC for urine protein (0.854) and albumin (0.872) was significantly higher than for the two low molecular weight proteins. AUC for all four urinary markers in NS patients was significantly lower than in BEN patients, ranging between 500 and 595. Median urine beta2-MG excretion in BEN patients was 17.5 times higher than in GN patients and 18.3 times higher than in controls; median alpha1-MG excretion was higher only 3.0 and 2.25 times, respectively. In the differentiation of BEN from healthy controls, beta2-MG had higher sensitivity and specificity at the cutoff levels (p < 0.001) than alpha1-MG (p < 0.05). In the differentiation of BEN from GN, beta2-MG was the best marker.?Conclusion:?All four urinary markers can be used for the differential diagnosis of BEN, beta2-MG being the best. Like in aristolochic acid nephropathy, beta2-MG seems to be an early marker of tubular damage in BEN.