Urinary IL-8 is a marker of early and long-term graft function after renal transplantation.

In this study, we examined whether the IL-8 content of urine sampled on day 1 and day 14 after renal transplantation is a marker of early and long-term renal function. Moreover, we assessed whether its concentration is positively correlated with the matrix metalloproteinase-9 (MMP-9) content of urine sampled on day 1 and day 30 and 12 months after renal transplantation. Our analysis covered 87 patients who underwent a kidney transplant. The patients were observed for an average of 30 months (12-60 months). The IL-8 concentration determined on day 1 was significantly negatively correlated with creatinine clearance early after renal transplantation (on days 1, 7, 14 and 30), as well as during long-term observations. IL-8 concentration in urine sampled on day 1 and day 14 was higher in patients demonstrating DGF than in those without DGF. No relationship was found between IL-8 content and cold ischaemia time. MMP-9 activity determined on day 1 and month 3 after renal transplantation was positively correlated with the IL-8 content determined in urine sampled on day 1, Rs = +0.32, p < .05 and Rs = +0.31, p < .05, respectively. The results of this study suggest that a high IL-8 content in urine sampled on day 1 after renal transplantation is an unfavourable marker of early and long-term (years-long) graft function. A high IL-8 content in urine sampled on day 1 after renal transplantation was positively correlated with the activity of metalloproteinase-9 in urine. This proves that both of these chemokines cooperate in ischaemia-reperfusion injuries in transplanted kidneys.

N-acetyl-beta-glucosaminidase urine activity as a marker of early proximal tubule damage and a predictor of the long-term function of the transplanted kidneys.

INTRODUCTION: Ischaemia-reperfusion injury (IRI) is a factor leading to the damages of the transplanted kidney, what affects mainly the proximal tubules. Early monitoring of tubule damage can be an efficient tool to predict the allograft dysfunction. Present in proximal tubules, N-acetyl-beta-glucosaminidase (NAG) is a lysosomal enzyme whose excretion rises as a result of IRI or acute rejection. The aim of this study was to monitor the NAG urine activity to evaluate the early proximal tubule damage, and to try to predict the long-term function of the transplanted kidney. MATERIAL AND METHODS: The study enrolled 87 Caucasian renal transplant recipients (61.7% males, 38.3% females, mean age 45.56±14.34 years). Urine samples were collected for NAG and creatinine analysis on the 1st day after transplantation, and then in the 3rd and 12th month. Protocol biopsies were performed in the 3rd and 12th month. RESULTS: A significant positive correlation between NAG urine activity in the 3rd month after transplantation and creatinine concentration on the 14th (p=0.004) and 30th day (p=0.05), in the 3rd month (p=0.009) and after the 1st (p=0.005) and 2nd year (p=0.003) was observed. A statistically significantly higher urinary NAG activity in samples collected in the first 3 days and in the 3rd month after transplantation among patients with DGF (p=0.006 and p=0.03 respectively) was found. There was a significant positive correlation between NAG urine activity in the 3rd month and the grade of tubular atrophy in specimens collected in the 3rd (p=0.03) and 12th (p=0.04) month. CONCLUSIONS: Monitoring of NAG urine activity is useful in the evaluation of early proximal tubule damage and predicting the long-term function of the transplanted kidneys.

Urinary lysosomal enzyme excretion in pregnant women with hypertensive disorders.

BACKGROUND: The authors assessed proximal renal tubular dysfunction and/or damage in pregnant women with various types of hypertension by measuring the three urinary lysosomal enzyme levels: N-acetyl-ß-d-glucosaminidase (NAG), arylsulfatase A and ß-glucuronidase. METHODS: The study consisted of 120 pregnant women divided into four groups: 41 women in 20th week of gestation or more, with pregnancy-induced hypertension (PIH group), 28 pregnant women after 20 weeks of pregnancy with pre-eclampsia (PE group), 21 pregnant women with chronic hypertension, identified before 20th week of pregnancy (CH group) and 30 healthy, pregnant women (healthy controls (HC) group). RESULTS: Statistical analysis showed significantly higher levels of all the three of lysosomal enzymes in the urine of patients with PE compared with the healthy pregnant women, pregnant women with PIH and the ones with chronic hypertension. Additionally, significantly higher values of NAG were found in the group of pregnant women with PIH compared with healthy pregnancies. No correlation was found between the concentration of enzymes in urine and values of blood pressure in any of the analyzed groups of pregnant women. CONCLUSIONS: The authors conclude that higher values of all the studied enzymes in PE group, in the comparison with the other groups, indicate proximal tubular damage at the cellular level. The lack of correlation between the concentration of lysosomal enzymes and blood pressure suggests that the damage to these parts of kidney is complex. In addition, mechanisms other than hypertension realizing intracellular enzymes may be involved in this process.