Posttransplant inflammation associated with onset of chronic kidney disease.

BACKGROUND: Chronic allograft nephropathy (CAN), a major complication in renal transplant patients, is an important cause of graft loss. Inflammation as measured in the pretransplant and posttransplant phases, using various markers, has been associated with worse renal function and a greater risk of cardiovascular disease and of long-term graft loss. OBJECTIVE: The objective of our study was to evaluate whether worsening inflammation in the first 3 months postoperatively was a risk factor for developing CAN. PATIENTS AND METHODS: We performed a cross-sectional study in 207 patients. The following markers of inflammation (MIF) were determined pretransplant and at 3 months after grafting: C-reactive protein (CRP) (mg/L), interleukin (IL)-6 (pg/mL), IL-10 (pg/mL), tumor necrosis factor (TNF)-α (pg/mL), and its soluble receptor (ng/mL), soluble-IL2R (UI/mL), pregnancy-associated plasma protein A (PAPP-A; mUI/L), and IL-4 (pg/mL). We also calculated the ratio at 3 months versus the pre value of MIF. RESULTS: CAN was diagnosed after the first year in 23 patients (11.3%) always by renal biopsy performed for clinical indications. Patients with CAN showed worse inflammation, eg, MIF ratios over one, with statistically significant differences for the ratios of TNF-α and PAPP-A (P=.032 and P=.051 respectively). Upon multivariate logistic regression analysis, using CAN as the dependent variable and age, sex, donor age, months on dialysis, acute tubular necrosis, acute rejection, and MIF ratios as covariates, we observed that an acute rejection episode (OR=13.03; CI=2.8-60.9; P=.001), CRP ratio (OR=1.36; CI=1.07-1.73; P=.013), and PAPP-A ratio (OR=1.80; CI=0.92-3.53; P=.005) were independent markers of CAN. CONCLUSIONS: Among other factors, inflammation may determine the onset of CAN as diagnosed by renal biopsy.

Inflammation, metalloproteinases, and growth factors in the development of carotid atherosclerosis in renal transplant patients.

BACKGROUND: Cardiovascular disease is the leading cause of death in renal transplant (RT) patients. Both traditional and emerging risk factors, some of which are controversial, have been described in the pathogenesis of cardiovascular disease. Carotid ultrasound (CUS) is considered to be an excellent diagnostic tool for subclinical atherosclerosis. OBJECTIVE: To evaluate the relationship between biomarkers of inflammation, growth factors, metalloproteinases, and the development of subclinical atherosclerosis diagnosed by using CUS. METHODS: We studied 93 RT patients (aged 54±12 years; 67.9% men; 13.5% with pre-RT diabetes mellitus). The following biomarkers were determined in the patients' blood hours before RT: C-reactive protein (CRP) and serum amyloid A using nephelometry; interleukin (IL) 2, 6, 8, and 10 and soluble IL-2 receptor, tumor necrosis factor (TNF) α, vascular endothelial growth factor (VEGF), epidermal growth factor, and monocyte chemotactic peptide using chemoluminescence; and pregnancy-associated plasma protein (PAPP)A using ELISA. A CUS was carried out during the first month after RT. RESULTS: Carotid intima-media thickness (IMT) was elevated in 51% of the patients, and 50.5% of the patients had atherosclerotic plaque. Both plaque (P=.004) and IMT (P=.001) correlated with age, and the increase of IMT was progressive, on both the left and the right side. Pre-RT CRP, IL-8, TNF-α, VEGF, MCP-1, and PAPP-A were significantly more elevated in patients with plaque. In the multivariate analysis adjusted for clinical variables, age (odds ratio [OR], 1.05; 95% confidence interval [CI], 1.01-1.10; P=.04), CRP (OR, 7.5; 95% CI, 2.05-27.3; P=.002), IL-8 (OR, 4.73; 95% CI, 1.27-17.6; P=.02), and PAPP-A (OR, 4.45; 95% CI, 1.22-16.2; P=.023) were independent markers of the presence of plaque. CONCLUSIONS: Age, CRP, IL-8, and PAPP-A, and not growth factors, are markers of carotid atheromatous plaque in RT patients.

Antioxidant enzymes and fatty acid status in erythrocytes of Down's syndrome patients.

The excess of genetic information in patients with Down's syndrome (DS) produces an increase in the catalytic activity of superoxide dismutase (SOD1), an antioxidant enzyme coded on chromosome 21. It has been suggested that an increase in oxidative stress in DS patients may cause adverse effects in the cell membranes through the oxidation of polyunsaturated fatty acids (PUFAs). The aim of this study was to evaluate the cellular antioxidant system by determining the catalytic activity of the SOD1, glutathione peroxidase (GPx), catalase (CAT), and glutathione reductase (GR) enzymes and the concentrations of alpha-tocopherol in red blood cells (RBCs) in a group of 72 DS patients. The profile of fatty acids in the phospholipids of RBC membranes was also evaluated. The activity of the erythrocyte antioxidant enzymes is significantly higher in the DS group than in the control group (SOD1, 635 +/- 70 U/g Hb vs 476 +/- 67 U/g Hb; CAT, 1843 +/- 250 U/g Hb vs 1482 +/- 250 U/g Hb; GPx, 23.2 +/- 5.3 U/g Hb vs 21.5 +/- 3.6 U/g Hb; and GR, 9.32 +/- 1.4 U/g Hb vs 6.9 +/- 1.3 U/g Hb, respectively). No differences were observed in RBC alpha-tocopherol concentrations between the two groups studied. Long-chain n6 PUFA (C20:3n6, C20:4n6) concentrations were increased in DS patients, suggesting enhanced delta-6-desaturase activity. The long-chain n3 PUFA (docosahexenoic acid) does not appear to be affected by increased oxidative stress, probably because of the existence of compensatory antioxidant mechanisms.