Sami Uzun

Changes in endothelial function before and after renal transplantation

Endothelial dysfunction is an early key event in the development of atherosclerotic cardiovascular disease observed in chronic renal failure patients. The role of renal transplantation (RTx) on endothelial dysfunction is still unclear. The aim of this study was to evaluate the endothelial function of chronic renal failure patients before RTx (while they were on hemodialysis, HD), and after RTx (at the 6th and 12th months) by a noninvasive method, brachial arterial ultrasound. A total of 22 (17 male, mean age: 33.9 ± 11.6 years) RTx recipients were enrolled in the study. Endothelium‐dependent vasodilation (EDD) was assessed by establishing reactive hyperemia. EDD prior to transplantation was significantly lower when compared with EDD measured at the 6th and 12th months after RTx (EDD pretransplantation: 6 ± 3.7%, EDD at the 6th month of RTx: 8.3 ± 2.3% and EDD at the 12th month of RTx: 12.1 ± 3.6%, P < 0.001). When the EDD values measured at the 6th and 12th months of RTx were compared, measurements of the 12th month were found significantly higher than those of the 6th month (P < 0.001). Our results also showed that RTx has provided improvement in endothelial function by eliminating the uremic environment although not in the early post‐RTx period.

Nutritional risk in hospitalized patients: impact of nutritional status on serum prealbumin

OBJETIVO: Falha no reconhecimento e acompanhamento do estado nutricional e a razao mais importante da desnutricao em pacientes hospitalizados. Este estudo objetivou avaliar o estado nutricional dos pacientes e comparar os resultados com os niveis sericos de pre-albumina. METODOS: Foram incluidos 97 pacientes no estudo, internados consecutivamente. O risco de desnutricao foi avaliado de acordo com dados antropometricos e com a Avaliacao Subjetiva Global e Triagem de Risco Nutricional 2002. Os estados nutricionais dos pacientes foram comparados com suas idades, sexo, indice de massa corporal, historico medico, perda de peso e analises bioquimicas, incluindo pre-albumina e tempo de permanencia hospitalar. RESULTADOS: De acordo com o Triagem de Risco Nutricional 2002, 57% dos pacientes estavam desnutridos ou em risco de desnutricao, apresentando boa correlacao com o Avaliacao Subjetiva Global (p<0,001, r=0,700). A analise multivariada mostrou correlacoes positivas entre desnutricao e idade, perda de peso, malignidade e proteina reativa-C (p=0,046, p=0,001, p=0,04 e p=0,002). Um escore ³3 no Triagem de Risco Nutricional 2002 foi associado a internacao prolongada (p<0,001). Houve correlacao entre pre-albumina serica e o estado nutricional, independente do numero de doencas cronicas e biomarcadores de inflamacao (p=0,01). A sensibilidade, especificidade, valor preditivo positivo, valor preditivo negativo e valor diagnostico da pre-albumina na avaliacao do risco de desnutricao foram de 94%, 32%, 0,67, 0,78 e 69, respectivamente. Apos sete dias de suporte nutricional, o risco de desnutricao caiu em 12% (p<0,001) e os niveis sericos de pre-albumina aumentaram em 20% (p=0,003). CONCLUSAO: Ao inves de refletir o estado nutricional global do paciente, niveis sericos baixos de sericos de pre-albumina podem ser vistos como um sinal de maior risco de desnutricao, exigindo uma avaliacao nutricional mais extensa. A analise serica de pre-albumina pode ser usada para o monitoramento de pacientes recebendo suporte nutricional.

Role of Plasmapheresis Performed in Hemodialysis Units for the Treatment of Anti‐Neutrophilic Cytoplasmic Antibody‐Associated Systemic Vasculitides

Anti‐neutrophilic cytoplasmic antibody (ANCA) positivity is seen in some systemic necrotizing vasculitides. Wegeners granulomatosis and microscopic polyangiitis are among the ANCA‐associated systemic vasculitides (AASV) and mortality is very high when renal failure occurs together with alveolar hemorrhage. The role of plasmapheresis in the treatment of these diseases has been studied retrospectively. Twelve patients with AASV who had plasmapheresis together with immunosuppressive medications have been involved. Primary diseases, immunosuppressive protocols, the number of plasmapheresis sessions, the amount of plasma that has been exchanged, urea and creatinine levels before and after treatment, pulmonary findings, the need for hemodialysis, and the outcome of patients were recorded. The mean age of patients was 52.9 ± 18.2 years. Wegeners granulomatosis was diagnosed in seven (58.3%) and microscopic polyangiitis in five (41.7%) patients. All patients had pulse cyclophosphamide and methylprednisolone followed by maintenance doses and plasmapheresis. Seven patients had hemodialysis at the beginning, and hemodialysis needed to be continued in three patients. Partial and complete remission was seen in 6 (50%) and 3 (25%) patients, respectively, and pulmonary findings regressed in all patients. End‐stage renal disease develops generally in AASV due to rapidly progressive glomerulonephritis causing severe irreversible glomerular damage. The mortality rate rises to 50% in cases of renal failure with diffuse alveolar hemorrhage; therefore, pulse immunosuppressive treatment with plasmapheresis may be life‐saving, as shown in our study.

The effect of different doses and types of intravenous iron on oxidative stress and inflammation in hemodialysis patients

BACKGROUND Although intravenous iron (IVI) is thought to have potential inflammatory and atherogenic effects, there are not enough studies comparing these effects in chronic hemodialysis (HD) patients. In this study, different doses and types of IVI were examined for effects on inflammation and oxidative stress. METHODS Chronic HD patients (n=101) were grouped into those not receiving IVI (group 1, n=29), those getting intermittent iron sucrose (group 2, n=25), those receiving intermittent iron dextran (group 3, n=24) and those getting a once monthly total dose of iron dextran (group 4, n=23). Malondialdehyde (MDA), advanced oxidation protein product (AOPP), C-reactive protein (CRP) and TNF-α levels were measured on days 0, 2, 7 and 28. RESULTS Groups were similar regarding age, sex, hemoglobin, iron indices and total amount of IVI given monthly. Although MDA levels at days 7 and 28, AOPP levels at days 0 and 28, CRP levels at day 28 and TNF-α level at day 7 were higher than at other days, there were no significant differences between the IVI groups on statistical analysis. CONCLUSION The different types and doses (intermittent or once monthly total dose) of IVI treatments are well tolerated without negative effects on the markers of lipid and protein oxidation and inflammatory indices in chronic HD patients.

Changes in the inflammatory markers with advancing stages of diabetic nephropathy and the role of pentraxin-3

Abstract Background: Immunological and inflammatory mechanisms have been shown to have role in both the development and progression of diabetic nephropathy (DNP). There is need for more specific markers for inflammation as the ones commonly used are influenced by many factors. Pentraxin-3 (PTX-3) seems to be a potential candidate. We aimed in our study to evaluate the changes of PTX-3 levels in different stages of DNP and its relationship with other inflammatory markers. Methods: This is a cross sectional study in which patients with DNP at different stages were involved. Patient were divided into three groups according to estimated glomerular filtration rate (eGFR), microalbuminuria and proteinuria levels: Group-1: eGFR >60 mL/min and microalbuminuria, Group-2: eGFR >60 mL/min and macroalbuminuria, Group-3: eGFR <60 mL/min and macroalbuminuria. Besides the routine biochemical parameters, levels of PTX-3, high sensitivity C-reactive protein (hsCRP), interleukin (IL)-1 and tumor necrosis factor (TNF)-α was measured. Groups were compared with each other regarding the study parameters and correlation of PTX-3 with other markers was evaluated. Results: The mean PTX-3 level in Group-2 (0.94 ± 0.26 ng/mL) and -3 (1.35 ± 1.55 ng/mL) were higher than in Group-1 (0.81 ± 0.25 ng/mL) (p = 0.009 and p = 0.012). There was a significant correlation of PTX-3 with proteinuria (r = 0.266, p = 0.016), microalbuminuria (r = 0.304, p = 0.014) and hypoalbuminemia (r = 0.197, p = 0.043). PTX-3 was not correlated with other markers of inflammation (IL-1, TNF-α and hsCRP) and diabetic metabolic parameters (hbA1c, C-peptide, insulin and HOMA-IR). PTX-3, IL-1 and TNF-α levels increased with the advancing stage of DNP while hsCRP level did not change. Conclusion: PTX-3 that increases similar to other markers of inflammation (IL-1, TNF-α) is a better inflammatory marker than hsCRP. Furthermore, there is a relationship between PTX-3 and proteinuria independent from eGFR.

Aspirin Resistance in Patients Undergoing Hemodialysis and Effect of Hemodialysis on Aspirin Resistance

The aim of this study was to evaluate the prevalence of aspirin resistance (AR) in patients undergoing hemodialysis (HD) and to assess the effect of HD on the results of the Multiplate test. A total of 54 patients undergoing HD were included in this study. Blood samples were taken just before and after the HD session. To determine AR, we used Multiplate test. Platelet aggregation values of the study population were 363.01 ± 225.69 aggregation unit (AU) × minutes before and 375.33 ± 254.05 AU × minutes after the HD (P = .597). There was strong correlation between the values before and after HD (R = .755, P < .0001). The AR status was changed in 9 (16.6%) patients after HD. Agreement of AR status before and after HD was substantial (κ coefficient = .667, P < .0001). The prevalence of AR in patients undergoing HD seems higher than in most of the studied populations, and this study has shown that the AR statuses of a significant number of patients undergoing HD change after an HD session.

The relationship of Prohepcidin levels with anemia and inflammatory markers in non-diabetic uremic patients: a controlled study.

Abstract Introduction: Hepcidin, a small peptide hormone synthesized in the liver, plays central role in regulation of iron metabolism. Hepcidin generation in chronic kidney disease (CKD) is dependent on iron status, anemia, inflammation, and hypoxia and erythropoietin levels. In our study, the relationship between Prohepcidin levels and inflammation and iron indices in non-diabetic uremic patients was investigated. Methods: This study has a cross-sectional design which includes four groups: Non-diabetic 21 patients with stage 4 CKD (predialysis), 20 hemodialysis (HD) and 21 peritoneal dialysis (PD) patients and 17 healthy volunteers as the control group. Complete blood count, iron, total iron binding capacity (TIBC), ferritin, high-sensitive C-reactive protein (hsCRP), fibrinogen, parathyroid hormone, interleukin (IL)-6 and Prohepcidin levels were recorded. Results: Serum Prohepcidin levels in the predialysis, HD, PD and the control groups were 119.6 ± 45.1 ng/mL, 140.2 ± 41.8 ng/mL, 148.2 ± 35.0 ng/mL and 93.8 ± 21.9 ng/mL, respectively (p < 0.001). Prohepcidin was positively correlated with urea (r = 0.345, p = 0.002), creatinine (r = 0.465, p < 0.001), phosphorus (r = 0.253, p = 0.025), hsCRP (r = 0.275, p = 0.019), duration of dialysis treatment (r = 0.443, p < 0.001), fibrinogen (r = 0.467, p < 0.001) and IL-6 (r = 0.615, p < 0.001) levels. A negative correlation was detected between Prohepcidin levels and albumin (r = −0.286, p < 0.001), TIBC (r = −0.573, p < 0.001), GFR (r = −0.473, p < 0.001), hemoglobin (r = −0.351, p = 0.002) and hematocrit (r = −0.342, p = 0.002) levels. Discussion: Prohepcidin levels increase with deepening anemia and show positive correlation with inflammatory markers. Therapeutic interventions regarding Prohepcidin action on inflammatory status may play a role in the treatment of anemia due to inflammation. Functional iron deficiency is frequent in uremic patients. It may be beneficial to measure Prohepcidin level together with ferritin among these patients.

Placement of Hemodialysis Catheters with a Technical, Functional, and Anatomical Viewpoint

Aims. Vascular access is of prime importance for hemodialysis patients. We aimed to study early complications of hemodialysis catheters placed in different central veins in patients with acute or chronic renal failure with or without ultrasound (US ) guidance. Material and Methods. Patients who were admitted to our unit between March 2008 and December 2010 with need for vascular access have been included. 908 patients were examined for their demographic parameters, primary renal disease, and indication for catheterization, type and location of the catheter, implantation technique, and acute complications. Results. The mean age of the patients was 60.6 ± 16.0 years. 643 (70.8 %) of the catheters were temporary while 265 (29.2%) were permanent. 684 catheters were inserted to internal jugular veins, 213 to femoral, and 11 to subclavian veins. Arterial puncture occurred in 88 (9.7%) among which 13 had resultant subcutaneous hematoma. No patient had lung trauma and there had been no need for removal of the catheter or a surgical intervention for complications. US guidance in jugular vein and experience of operator decreased arterial puncture rate. Conclusion. US-guided replacement of catheter to internal jugular vein would decrease complication rate. Referral to invasive nephrologists may decrease use of subclavian vein. Experience improves complication rates even under US guidance.

Tuberculosis in patients on hemodialysis in an endemic region.

Clinical presentation of tuberculosis is different in hemodialysis patients than in the general population. This study aimed to analyze hemodialysis patients with tuberculosis in Istanbul. Patients who were on a chronic hemodialysis program in Istanbul for more than 3 months and diagnosed to have tuberculosis at least 3 months after the start of hemodialysis were included. To discard the effect of immigration from other cities, we included only patients who had started their dialysis program in Istanbul. Their demographic and clinical data were analyzed using Statistical Package for Social Sciences for Windows ver. 13.0. Of the 925 patients screened from 7 different centers, 31 (3.35%) were found to have tuberculosis. The mean age was 52.3±13.5 years. The male/female ratio was 18/13. The mean duration of dialysis therapy and the duration of dialysis till the diagnosis of tuberculosis were 62.6±54.3 and 21.7±25.7 months, respectively. Extrapulmonary tuberculosis constituted 48.39%. Treatment ended with a cure in 18 (58.05%); was still ongoing in 12 (38.70%) patients; and 1 (3.25%) died of pulmonary tuberculosis. The lower incidence of tuberculosis compared with previous reports may be related to the differences in the diagnostic criteria and the decrease in the rate of tuberculosis during recent years. The demographic and clinical parameters of the patients were quite similar to the average dialysis population in Turkey. Hence, we cannot address a subpopulation with additional risk. It is important to prevent tuberculosis in hemodialysis patients due to difficulties in the diagnosis and treatment. Thus we recommend routine screening of hemodialysis patients and effective isolation and treatment of infected patients.

Thrombotic thrombocytopenic purpura associated with multiple myeloma.

Thrombotic thrombocytopenic purpura is a thrombotic microangiopathic disease. Associations with collagen vascular diseases, pregnancy, some drugs, surgical intervention, and infections are documented (known). Malignancy is also one of the known factors associated with thrombotic thrombocytopenic purpura. These malignancies are usually the disseminated solid organ tumors. Hematological malignancies constitute a rare association. Here, we present a patient with thrombotic thrombocytopenic purpura associated with multiple myeloma and discuss the pathogenesis. To our knowledge, this is the first case report of thrombotic thrombocytopenic purpura associated with multiple myeloma.