Assessment of oxidative status in patients with acute kidney injury: a pilot study.

Extensive experimental evidence confirms the role of oxidative stress as a major contributor to the pathogenesis of acute kidney injury (AKI). However, less information is available on the evolution of prooxidant-antioxidant parameters from early to end-phase renal function decline in humans. This study aimed to determine the oxidative status in dynamic throughout the evolutionary phases of the disease. The study included patients with cardiovascular pathology and AKI hospitalized in the intensive care unit (n = 69) and age-matched healthy controls (n = 30). They were followed through three phases of AKI; the first [corrected] phase was the phase of diagnosis, which is characterized by oliguria/anuria, the [corrected] second phase was established diuresis, and the [corrected] third phase was the polyuric phase. In these phases of the disease, blood samples were taken from the patients for biochemical analysis. From the collected whole blood, we measured spectrophotometrically prooxidants: index of lipid peroxidation, measured as Thiobarbituric acid reactive substances (TBARS), nitrite (NO2⁻), superoxide anion radical (O2⁻) and hydrogen peroxide (H2O2), and antioxidants: activity of superoxide dismutase (SOD), catalase (CAT) and reduced glutathione (GSH) from erythrocyte lysate. Comparing the results of the three measurements, a significant difference was found in the levels of NO2⁻ and GSH, both of which increased in the second phase (P < 0.05) and then decreased in the third phase, and a significant increase in TBARS, which was elevated in the second phase (P < 0.05) and did not change significantly until the third phase. Our results showed phase-dependent modification in 3 parameters of the oxidative status (TBARS, NO2⁻ and GSH). Whether these changes contribute to the deterioration of renal function in AKI remains to be established.

Levels of transforming growth factor ß1 during first six months of peritoneal dialysis.

Transforming-growth factor ß1 (TGF-ß1) is a powerful cytokine involved in physiological processes of growth, differentiation, gene expression, embryogenesis, tissue remodelling, wound healing as well as tumorigenesis, immunosuppression and fibrosis, like peritoneal membrane fibrosis on long-term peritoneal dialysis (PD) treatment. The aims of this study were to determine TGF-ß1 levels in serum (s) and drained dialysate (dd), to assess their relations to sex, age, diabetes, dialysis modality, peritonitis and use of erythropoiesis stimulating agents (ESAs), inhibitors of angiotensin-converting enzyme (ACEi) and/or statins in 20 patients, 11 men and 9 women, mean age 62.90 ± 12.69 years, free of peritonitis during the first 6 months of PD treatment. There was no statistically significant difference in TGF-ß1 concentrations in serum and drained dialysate at the beginning and after first 6 months of chronic PD, in patients of different sex, age and diabetic patients versus non-diabetic. The significant positive correlations between sTGF-ß1 levels and glycemia at the beginning and cholesterolemia after 6 months of PD treatment suggest higher TGF-ß1 concentrations in patients with unfavorable metabolic profile. Expression of TGF-ß1 in effluent dialysate was significantly lower in patients on chronic PD using ACEi therapy, suggesting ACEi to have a protective effect on peritoneal membrane. Patients on ESA had slightly lower sTGF-ß1 concentrations after the first 6 months of PD treatment.

Levels of Vascular Endothelial Growth Factor during First Six Months of Peritoneal Dialysis.

INTRODUCTION: Chronic peritoneal dialysis (PD) up-regulates vascular endothelial growth factor (VEGF) synthesis and VEGF is found in drained dialysate (dd). OBJECTIVE: Aims of this prospective study were to evaluate serum (s) and ddVEGF concentration during the first six months of PD, relationships between these concentrations and demographic and biochemical parameters, presence of diabetes, peritonitis, and the use of medications. METHODS: The study included 20 patients, with the mean age of 62.9±12.69, 11 of whom were affected by diabetes mellitus. Fasting venous blood samples were taken at the beginning and after six months of PD, in tri-potassium ethylenediaminetetraacetic acid (K3EDTA) vacutainer. RESULTS: After six months of PD, sVEGF concentrations increased significantly, without significant change in ddVEGF. Concentrations of sVEGF at the beginning of chronic PD treatment directly significantly correlated with serum fibrinogen, and after six months with fibrinogen and glycemia. In patients receiving erythropoiesis-stimulating agent (ESA), levels of sVEGF and ddVEGF were lower at baseline, while after six months of PD ddVEGF increased. in patients not receiving ESA, sVEGF increased more prominently, while ddVEGF decreased.The changes were not statistically significant. Patients receiving angiotensin-converting-enzyme inhibitor (ACEi) had sVEGF and ddVEGF levels insignificantly lower than those not using ACEi, however sVEGF significantly increased during six months of PD. After six months of PD, ddVEGF was significantly higher compared to those not using ACEi. Treatment with statins did not significantly influence levels of sVEGF and ddVEGF during the follow-up. Concentrations of sVEGF were continually lower than those of ddVEGF and increased more, while concentrations of ddVEGF were higher in patients using statins. CONCLUSION: Serum and drained dialysate concentrations of VEGF in PD patients were connected with poorer metabolic profile, while the role of inflammation and treatment agents should be studied further.

Vascular endothelial growth factor in peritoneal dialysis patients.

BACKGROUND: Vascular endothelial growth factor (VEGF) is a glycoprotein which exerts mitogenic effects on endo thelial cells, enhances neoangiogenesis and microvascular permeability, influences leukocyte kinetics when upreg ulated by hypoxia and high-glucose concentration in experimental conditions and in human pathology. Peritoneal synthesis of VEGF has been demonstrated in patients on peritoneal dialysis (PD) treated with glucose-based dialy sate solutions. METHODS: The aim of the study was to determine the serum and peritoneal effluent VEGF concentrations in patients on chronic PD and to assess the relationship between age, gender, comorbidities, dialysis modality and vintage, therapy with erythropoiesis stimulating agents (ESA), angiotensin-converting enzyme inhibitors (ACEi) and statins and VEGF concentrations. Data on the use of ACEi, ESA, and statins were collected from patients' medical histories. VEGF was measured in serum and peritoneal effluent using the quantitative sandwich enzyme immunoassay (ELISA) kits (Quantikine® Human VEGF, R&D Systems, USA & Canada). Complete blood count and standard biochemical analyses (serum glucose, urea, creatinine, total protein, albumin, cholesterol, triglycerides, sodium, potassium, chloride, iron, total iron-binding capacity, ferritin, fibrinogen, C-reactive protein, and intact parathyroid hormone) were performed in fasting venous blood samples. Dialysis and residual components of Kt/V and normalized weekly creatinine clearance were calculated based on 24-hour urine and effluent collections. Peritoneal transport type was determined using the peritoneal equilibration test. RESULTS: Samples from 63 PD patients (39 males and 24 females, average age 61.97 ± 11.01 years) were analyzed. The average serum and effluent VEGF concentrations (231.84 ± 173.91 pg/mL and 38.39 ± 49.38 pg/mL, respectively) correlated significantly (p = 0.002). No significant difference was found in serum and effluent VEGF concentrations in relation to demographic characteristics, comorbidities, dialysis modality, therapy with ESA, ACEi, and statins. Patients treated with PD longer than 5 years had significantly higher serum VEGF levels (p < 0.05). Correlation analysis showed a statistically significant relationship between statin therapy and lower effluent VEGF concentration (p = 0.030). Serum VEGF concentration significantly correlated with fibrinogen serum concentration (p = 0.034) and glycemia (p = 0.004). Effluent VEGF concentration significantly correlated with cholesterolemia (p = 0.004). CONCLUSIONS: Serum VEGF concentrations were significantly higher in long term PD patients, and peritoneal effluent VEGF concentrations were significantly lower in patients receiving statins, suggesting a protective effect of those drugs on peritoneal membrane.

[A patient with systemic lupus erythematosus and lupus nephritis: a 12-year follow-up].

INTRODUCTION: Systemic lupus erythematosus (SLE) is a chronic immunological disease causing a significant morbidity and mortality in younger women and involving several organs and systems, most often the kidneys, being consequently the incidence of lupus nephritis (LN) about 60%. CASE REPORT: We reported a 57 year-old patient with the diagnosed SLE in 1995. Pathohistological analysis of kidney biopsy revealed LN type V. The patient was treated with corticosteroid pulses and azathioprine during one year. A remission was achieved and maintained with prednisone, 15 mg daily. Nephrotic relapse was diagnosed in 2006 and the second kidney biopsy revealed recent kidney infarction due to extensive vasculitis. Soon, a cerebrovascul insult developed and CT-scan revealed endocranial infarctus. The patient was treated with corticosteroids and cyclophosphamide pulses (totally VI monthly pulses), and also with low-molecular heparine, anticoagulants and salicylates because of the right leg phlebothrombosis. After the pulses, the patient was adviced to take prednisone 20 mg daily and azothioprine 100 mg daily, and 6 months later mycophenolate mofetil because of persistent active serological immunological findings (ANA 1:320) and nephrotic syndrome. Mycophenolate mofetil was efficient in inducing and maintaining remission of nephrotic syndrome. CONCLUSION: The aim of LN treatment is to achieve and maintain remission, improve patients' outcome, reduce the toxicity of immunosuppressive drugs and the incidence of relapses.Mycophenolate mofetil was shown to be efficient in inducing and maintaining remission of nephrotic syndrome in the frame of LN.

Evaluation of renal damage by urinary beta-trace protein in patients with chronic kidney disease.

BACKGROUND: Beta-trace protein (BTP) was found to be increased in the serum and urine of patients with renal diseases. The aim of this study was to compare the urinary levels of beta-trace protein with levels of other urinary proteins: albumin, beta2-microglobulin (B2M), alpha1-microglobulin (A1M), and cystatin C and to determine its clinical usefulness for detection of renal dysfunction in chronic kidney disease (CKD). METHODS: These markers were measured in 24-hour urine samples from 134 patients with CKD. RESULTS: BTP correlated significantly with A1M (r = 0.871), cystatin C (r = 0.759), total protein (r = 0.684), B2M (r = 0.497), and albumin (r = 0.448) in 24-hour urine samples (P < 0.05). Urinary BTP concentrations in patients with albuminuria below 30 mg/day were significantly lower than in patients with albuminuria above 30 mg/day (P < 0.0001). ROC analysis showed high diagnostic accuracy of BTP for detection of > 30 mg/day albuminuria (AUC 0.908). Urinary BTP was also in significant correlation with the estimated glomerular filtration rate (r = -0.580). CONCLUSIONS: The results of our study suggest that BTP may be a useful and reliable urinary marker of renal dysfunction and may have a place in addition to urinary alpha1-microglobulin and albumin as an alternative marker for tubular damage and the magnitude of renal impairment in patients with chronic kidney disease.

[Secondary hyperparathyroidism--risk factor for development of cardiovascular complications in patients on hemodialysis].

INTRODUCTION Cardiovascular disease is a leading cause of death among hemodialysis patients. SECONDARY HYPERPARATHYROIDISM: Secondary hyperparathyroidism is one of the main factors for the development of cardiovascular complications among these patients. A high concentration of parathormone, hypercalcemia, hyperphosphatemia and high calcium x phosphate product among dialysis patients play a crucial role in the development of vascular (calcification of coronary artery) and valvular calcifications. DISCUSSION AND CONCLUSION With every new patient on hemodialysis it is necessary to see if there is a vascular/valvular calcification in order to single out the patients at risk of progression of coronary artery calcification and to use non-calcium containing binder phosphate in due time. Non-calcium containing binder phosphate, new active vitamin D agents and calcimimetics prevent the development of secondary hyperparathyroidism as well as cardiovascular complications and decrease the rate of cardiovascular morbidity and mortality of these patients.

Kinetics of C-reactive protein, interleukin-6 and -10, and phospholipase A2-II in severely traumatized septic patients.

BACKGROUND/AIM: Injury-induced anergy is one of the key factors contributing to trauma victims' high susceptibility to sepsis. This group of patients is mostly of young age and it is therefore essential to be able to predict as accurately as possible the development of septic complications, so appropriate treatment could be provided. The aim of this study was to assess kinetics of interleukin (IL)-6 and -10, phospholipase A2-II and C-reactive protein (CRP) in severely traumatized patients and explore the possibilities for early detection of potentially septic patients. METHODS: This prospective study included 65 traumatized patients with injury severity score (ISS) > 18, requiring treatment at surgical intensive care units, divided into two groups: 24 patients without sepsis and 41 patients with sepsis. C-reactive protein, IL-6 and -10 and phospholipase A2 group II, were determined within the first 24 hours, and on the second, third and seventh day of hospitalization. RESULTS: Mean values of IL-6 and phospholipase A2-II in the patients with and without sepsis did not show a statistically significant difference on any assessed time points. In the septic patients with ISS 29-35 and > 35 on the days two and seven a statistically significantly lower level of IL-10 was found, compared with those without sepsis and with the same ISS. C-reactive protein levels were significantly higher in septic patients with ISS 18-28 on the first day. On the second, third and seventh day CRP levels were significantly lower in the groups of septic patients with ISS 29-35 and > 35, than in those with the same ISS but without sepsis. CONCLUSION: Mean levels of CRP on the first day after the injury may be useful predictor of sepsis development in traumatized patients with ISS score 18-28. Mean levels of CRP on the days two, three and seven after the injury may be a useful predictor of sepsis development in traumatized patients with ISS score more than 28. Mean levels of IL-10 on the second and seventh day after the injury may be a useful predictor of sepsis development in traumatized patients with ISS score > 28.

Risk factors for aortic valve calcification in patients on regular hemodialysis.

INTRODUCTION: Aortic valve calcification (AVC) accelerates development of aortic valve stenosis and cardiovascular complications. Hyperphosphatemia is one of the key risk factors for aortic valve calcification. AIM: The aim of this study was to evaluate the prevalence of AVC in patients on regular hemodialysis and to assess the impact of different factors on its appearance. METHOD: The study investigated a total of 115 patients treated in the Hemodialysis Department of the Urology and Nephrology Clinic at the Kragujevac Clinical Center in Serbia. The variables investigated were: serum albumin, C-reactive protein (CRP), homocysteine, total cholesterol, LDL-cholesterol (LDL-C), HDL-cholesterol (HDL-C), triglycerides (TG), Apolipoprotein A-I (Apo A-I), Apolipoprotein B (Apo B) and lipoprotein (a), calcium, phosphate and parathormone, and calcium-phosphorus product (Ca x P). Patients were evaluated by echocardiography for AVC. Statistical analysis included univariate and multivariate logistic regression analysis. RESULTS: Univariate regression analysis showed that serum phosphate levels and Ca x P are the most important risk factors for AVC (p<0.001). Multivariate logistic regression analysis revealed that hyperphosphatemia is an independent risk factor for AVC (p<0.001). CONCLUSION: Hyperphosphatemia is an independent risk factor for aortic valve calcification.

Predicting multiple organ failure in patients with severe trauma.

OBJECTIVE: Pathophysiological processes in the first days after trauma seem to be important for the development and final outcome in cases of multiple organ failure (MOF). Our objective in this study was to assess the kinetics of C-reactive protein (CRP), interleukin-6 (IL-6), interleukin-10 (IL-10) and phospholipase A2 group II (PLA2-II) as predictors of more severe forms of MOF. As well, we sought to assess the criteria for systemic inflammatory response syndrome (SIRS) and Simplified Acute Physiology Score (SAPS II) values and to create predictive models of MOF development. METHODS: This prospective study recruited a sample from 75 patients treated for severe injuries at surgical intensive care units at the Clinical Center of Serbia. Of these patients, a total of 65 met the entry criteria, which included an Injury Severity Score >or= 18 (severe injury), age range 16-65 years, admission to the hospital within the first 24 hours after injury and survival longer then 48 hours. We excluded patients with primary injury to the central nervous system. RESULTS: When patients with and without MOF were compared, a statistically significant difference was noted in the average CRP and PLA2II levels on all days. IL-6 and IL-10 concentrations were significantly different on all days of hospitalization. CONCLUSION: According to the results of our study, it is possible to create predictive models with a high level of accuracy for the development of organ failure in traumatized patients. The most important parameters of MOF development are serum IL-6 concentration on the first day of hospitalization and the number of positive SIRS criteria on the fourth day of hospitalization.

Primary non-hodgkin lymphoma of urinary bladder with nine years later renal involvement and absence of systemic lymphoma: a case report.

AIMS: Primary bladder non-Hodgkin lymphoma (PBNHL) is very rare, especially as extranodal B-small lymphocytic lymphoma (B-SLL). Also, late isolated renal manifestation of PBNHL is extremely unusual. We report a very rare type of extranodal B-SLL of bladder wall with extremely unusual late isolated renal involvement, clinically manifested by nephrotic syndrome and incipient renal failure. A CASE REPORT: A 56-year-old woman was presented with a solitary tumor of bladder wall, with history of dysuria and night sweating. A transvaginal needle biopsy of the tumor was performed, and diagnosis of primary extranodal B-SLL was made in the absence of bone marrow, lymph node, or blood involvement. She was treated with chemotherapy until the achievement of complete remission. Nine years later, she developed nephrotic syndrome. The renal biopsy revealed parenchymal lymphoma's involvement associated with glomerular lesion. Immunohistochemical analysis confirmed the same imunophenotype of lymphoma cells like in bladder wall nine years ago. Restaging procedure showed no evidence of disease elsewhere. CONCLUSION: To our knowledge, it is the first case of association of very rare primary bladder B-SLL with late isolated renal involvement.

[Hepatorenal syndrome].

Hepatorenal syndrome is complication of the advanced cirrhosis characterized by functional renal failure and changes of systemic blood pressure due to increased activity of endogenous vasoactive systems. Functional renal failure is due to severe renal cortical ischemia and reduction of glomerular filtration rate (GFR) developing in the late stages of cirrhosis. The pathogenesis of hepatorenal syndrome is the result of an extreme underfilling of the arterial circulation secondary to arterial vasodilatation located in the splanchnic circulation. Reduced effective arterial blood volume triggers a compensatory response with activation of systemic and renal vasoconstrictor systems. At the same time, the ascites becomes refractory in some patients, as it is no longer responsive to diuretic treatment. These changes result from combination of deteriorating liver function and increasing portal pressure, further splanchnic vasodilatation, increase of circulating vasoconstrictors, and decrease of renal blood flow and GFR. Hepatorenal syndrome can be precipitated by shock, infection, nephrotoxic drugs, bleeding, surgery or large volume paracentesis. Renal failure may be rapidly progressive (type I HRS) or may develop more slowly (type II HRS), which is usually associated with refractory ascites. The diagnosis of HRS is based on established diagnostic criteria aimed at excluding the nonfunctional causes of renal failure. The prognosis of patients with HRS is very poor. Liver transplantation remains the only curative treatment for the time being. Pharmacological therapies based on the use of vasoconstrictor drugs may serve as a bridge to liver transplantation. Prevention of HRS by albumin infusion is recommended in patients with spontaneous bacterial peritonitis and by pentoxifylline in patients with the acute alcoholic hepatitis.

Studies of interactions between platinum(II) complexes and some biologically relevant molecules.

The reactions of Pt(II) complexes, cis-[Pt(NH3)2Cl2], [Pt(terpy)Cl]+, [Pt(terpy)(S-cys)]2+, and [Pt(terpy)(N7-guo)]2+, where terpy=2,2':6',2''-terpyridine, S-cys=L-cysteine, and N7-guo=guanosine, with some biologically relevant ligands such as guanosine-5'-monophosphate (5'-GMP), L-cysteine, glutathione (GSH) and some strong sulfur-containing nucleophiles such as diethyldithiocarbamate (dedtc), thiosulfate (sts), and thiourea (tu), were studied in aqueous 0.1 M Hepes at pH of 7.4 using UV-vis, stopped-flow spectrophotometry, and 1H NMR spectroscopy.

Histomorphometric characteristics of peritoneal blood microvessels.

We assessed histological characteristics and sex related differences in morphometric parameters of healthy persons' peritoneal blood vessels. Eighteen samples of parietal peritoneum were collected from 11 healthy persons with elective abdominal surgery, 6 males and 5 females, age range 44-58. Tissue samples were prepared for light and transmission electron microscopy. Morphometric parameters of peritoneal blood vessels were determined by analySIS 3.1 Soft Imaging System GMbH. We directly measured outer and lumen diameter, and outer and lumen surface on blood vessels transversal sections. Wall thickness, lumen diameter-wall thickness ratio, blood vessels numerical density and peritoneal tissue surface under blood vessels were calculated subsequently. Results were statistically analysed with Student T test. Mostly true and venous capillaries were observed. Endothelial citoplasm showed numerous mitochondria, ribosomes and pinocytotic vesicles, prominent rough endoplasmic reticulum, well-developed Golgi complex, and predominantly euchromatic nuclei. No statistically significant differences were found between male and female subjects in any of the investigated variables, rphometric characteristics of pelvic peritoneal blood vessels did not show gender related differences.

[Efficacy of bolus intravenous iron treatment in peritoneal dialysis patients].

INTRODUCTION: Normocytic, normochromic anemia is one of the first signs of chronic renal failure and it is common in patients on chronic dialysis treatment. It causes decrease in oxygen supply to tissues, increases cardiac minute volume, causes left ventricular hyperthrophy, cardiac insufficiency, disorders related to cognitive functions and immune response, and increases morbidity and mortality rates. The leading cause of anemia in patients on chronic peritoneal dialysis (PD) is iron depletion and most patients on PD need oral or parenteral iron supplementation. The aim of this study was to evaluate our first experience with bolus intravenous ferrogluconate therapy in patients on chronic peritoneal dalysis at the Nephrology Clinic of the Clinical Center of Serbia (CCS). MATERIAL AND METHODS: We examined 11 patients, 7 males and 4 females, mean-age 49 years (range 31 to 68 years) on chronic PD. All patients received blood transfusions, oral or intramuscular iron supplementation before 465 to 665 mg ferrogluconate therapy was given in 500 ml. saline intravenous infusion: 5 of them were on erythropoietin therapy and 2 of them started with EPO therapy after the ferrogluconate therapy. RESULTS: The blood count improved during the first 3 months after application of bolus intravenous iron therapy (ferrogluconate); erytrhopoietin dose was not increased during the follow-up. Some patients suffered from side effects during infusion and 6 patients received the complete treatment. DISCUSSION: Blood count improves in a number of patients affected by endstage renal desease during the first months on continuous ambulatory peritoneal dialysis (CAPD) treatment. But a large number of patients on chronic CAPD treatment are iron-depleted and they require oral or parenteral substitution. Side effects and complications of intravenous iron therapy were not severe and only one patient suffered from allergic manifestations. Ferremia and blood count improved in patients who did not receive erythropoietin during the follow-up, and patients on erythropoietin therapy required lower doses after receiving the intraveonous iron therapy. CONCLUSION: Blood count improvement and the lack of severe side effects speak in favor of further iron supplementation with bolus intravenous iron replacement.

[HIV infection and the kidneys (Part II): Morphologic changes and their diagnostic significance].

HIV-infected patients may be faced with a variety of renal problem patterns. HIV-associated nephropathy is a unique pattern of sclerosing glomerulopathy and represents the most rapidly progressive form of focal segmental glomerulosclerosis. This study involved the examination of 32 renal biopsies: by light, immunofluorescence, and electron microscopy, in order to determine the most accurate and reliable diagnostic procedure. The findings show that the most sensitive and accurate procedure is electron microscopy, capable of detecting specific EM changes very early on, which is sufficient for the diagnosis of HIV-associated nephropathy.

[Effect of uremia and peritoneal dialysis on peritoneal mesothelial cells]. / Uticaj uremije i peritoneurske dijalize na celije mezotela peritoneuma.

The aim of the study was to investigate the morphology of mesothelial cells of the peritoneum of patients with terminal renal failure (TRF), taken by the biopsy immediately before the onset of peritonal dialysis (PD), and to compare it with the findings in patients with PD. The samples were prepared in the way standard for light microscopy and transmission electron microscopy. In patients with TRF intracytoplasmatic inclusions could be observed, unusual protrusions of mesothelial apical surfaces, deformation of mesothelial cells and their detachment from the basal membrane, as well as the dilatated cisternae of granulated endoplasmatic reticulum with filamentous structures in some of them. In patients on PD cytoplasmic protrusions of different shapes and contents were observed at the surface of mesothelial cells, multiplication of basal membrane, occurrence of young forms of mesothelial cells as well as the detachment of those cells from the basal lamina.