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Data acquisition and data processing are at the core of pavement management systems. Nowadays, traditional methods of data collection are rarely used in developed countries due to the considerable disadvantages of the traditional methods compared to the automated ones, such as the slow pace of data collection, endangering the safety of the human operators collecting the data, considerable cost, collecting data from only a limited section of road networks, and inconsistency among the data collected by different operators. In contrast, automated methods alleviate the majority of these problems. However, the main drawback of the automated methods is the high cost of purchase, implementation, and maintenance of the equipment, which has deterred their use in developing countries with limited financial resources. To address this problem, developing a new automated method that reduces the production costs while keeping the required accuracy and performance seems imperative. The goal of this research is to investigate the use of microphones, as inexpensive equipment with acceptable accuracy, for collecting pavement macrotexture data, which is an input to the pavement management system. The proposed method is based on the tire/road interaction noise. To this end, a review of the previous researches on audio-based monitoring of various pavement features is presented. By considering the results of the related researches and the goals of this work, a new setup for data collection and an accompanying signal processing method is proposed. To develop and evaluate the proposed method, data from six standard road sections of a test field are collected. To process the collected data, PCA, Cepstrum, LPC, LSF, PSD, and Wavelet methods are employed. The SVM and KNN classification methods are used to evaluate the results of the signal processing step, which is performed in various frequency bands. The best results are obtained by using the Cepstrum signal processing method along with the SVM classifier in the 3000–5000 Hz frequency band resulting in an accuracy of 95% on the test data and the precision error of 1%.

Data collection of the pavement condition is the main core of the pavement management systems. The automated data collection method has some advantages over the traditional one such as safety, consistency, speed, and repeatability. However, one of the main disadvantages of the automated data collection is the high cost of required devices. It is necessary to present an innovative cost-effective automated data collection system with adequate accuracy and precision. Pavement roughness is one of the most important parameters showing the pavement condition and directly affecting the ride quality. The main aim of this research is to develop a new automated cost-effective data collection device for measuring roughness. An extra wheel equipped with accelerometers and a geographical positioning system are utilized for evaluating pavement roughness. Longitudinal profiles are employed to calculate the International Roughness Index through the application of a linear model with a high coefficient of determination of 0.87. The root-mean-square error and the average error percentage are sufficiently low, equal 10% and 20%, respectively.

Road surface friction is one of the most important parameters determining road safety and macrotexture is one of the important factors affecting it. There are two types of traditional and automated data gathering methods. One of the disadvantages of automated methods is the high cost of purchasing or manufacturing. The purpose of this study is evaluating the feasibility of a low-cost dynamic method based on tire/road noise to evaluate the macrotexture of cracked non-porous asphalt pavements. To this end, the tire/road noise gathering system has been developed inspired by the ISO 11819-2 standard. The developed system has been used for data collection alongside with the health monitoring system of the Amirkabir University of Technology. After data gathering, the relationship between macrotexture indices (laser-based) and tire/road noise features has been evaluated. Using artificial neural networks, models for relating different sound and macrotexture indices in each frequency band are presented with the best correlation result being R2 = 0.76 between MPD and power spectral density in the 500 to 1500 Hz frequency band. The results indicate that in cracked pavement surfaces, by focusing on the vibration mechanism, acceptable results can be achieved in macrotexture monitoring by using interaction noise.

Chronic kidney disease (CKD) continues to remain high globally, up to 13.4% by one estimate. Although the number, geographic distribution, size, and quality of the studies examining CKD prevalence and incidence have increased over the past decade, the global capacity for CKD surveillance is still far less developed than that for hypertension, diabetes, and cardiovascular disease. Estimating CKD prevalence is constrained by inadequate standardization of serum creatinine and urine albumin assays, heterogeneity in study designs, lack of national registries in many countries, incomplete adoption of disease classification guidelines, and inconsistent use of evidence-based equations for estimating glomerular filtration rate. Goal 1: Improve monitoring of CKD prevalence. To achieve this, disseminate the rationale for CKD prevalence monitoring, achieve uniform measurement of CKD markers, promote inclusion of CKD measurements in all large chronic disease cohorts and health surveys, harness administrative claims data for CKD surveillance, and incorporate the new CKD classification system in the International Classification of Diseases. Goal 2: Improve CKD monitoring of populations underrepresented in studies to date. To achieve this, establish registries of chronic dialysis and transplantation in all countries; establish registries for special CKD groups, such as children, patients with rare diseases, and patients with special etiologies of CKD. Goal 3: Improve identification of individuals with CKD. To achieve this, implement the Kidney Disease: Improving Global Outcomes guidelines for screening and testing, carry out randomized studies on screening strategies, ensure that estimated glomerular filtration rate is reported with all reports of serum creatinine, and leverage new software for identification and follow-up of CKD cases. Copyright (C) 2017, International Society of Nephrology. Published by Elsevier Inc. All rights reserved.

The focus of this article is to define goals and resulting action plans that can be collectively embraced by interested stakeholders to facilitate new therapeutic approaches to mitigate chronic kidney disease progression. The specific goals include identifying druggable targets, increasing the capacity for preclinical and early clinical development, broadening the availability of new therapeutic approaches, and increasing investment in the development of new therapies to limit chronic kidney disease. Key deliverables include the establishment of new regional, national, and global consortia; development of clinical trial networks; and creation of programs to support the temporary mutual movement of scientists between academia and the biotechnology and pharmaceutical sector. Other deliverables include cataloging and maintaining up-to-date records to collate progress in renal research and development, inventorying the capacity of research and clinical networks, and describing methods to ensure novel drug development.

In this study, an acoustical-based macrotexture measurement method that uses the friction-induced mechanism of tire/road noise has been proposed. This mechanism influences the frequencies above 1 KHz and is the dominant mechanism for frequencies above 3 KHz. The airflow due to this mechanism passes through the macrotexture which can be represented using convolution in the time-domain of the airflow, which is viewed as the input signal, and macrotexture, which is considered as the transmission channel. Using the Cepstral processing method, the related features to macrotexture airflow can be extracted and the macrotexture can be evaluated. To investigate the proposed method, interaction noise was measured for six uniform non-porous asphaltic test tracks with different macrotextures. The tire/road noise signal is passed through a bandpass filter (3–5 KHz). By liftering the cepstrum components in the range of 2–50, the feature vector has been obtained and then used as input to a multiclass SVM, resulting in a precision error of 4%.

Whether administrating of vitamin D supplements increases the risk of hypercalciuria is still unanswered. The aim of the present study was to determine whether use of vitamin D supplementation might increase the risk of hypercalciuria.This interventional study was conducted on 30 who suffered from vitamin D insufficiency and deficiency and also had a history of nephrolithiasis. The patients were treated with vitamin D supplement (50000 units per week for 2 months and then every 2 weeks until the end of the 3rd month). Serum and urinary biomarkers were measured at baseline and 3 months after start of vitamin D therapy.Administrating vitamin D supplement for 3 months led to a significant increase in serum level of 25-hydroxyvitamin D from 10.4 ± 4.2 ng/mL to 44.0 ± 10.7 ng/mL (P.001). Also, the median level of serum parathyroid hormone was significantly reduced from 53 ng/L (interquartile range, 22 ng/L to 163 ng/L) to 38 ng/L (interquartile range, 16 ng/L to 102 ng/L; P.001). There was also a significant increase in urinary citrate after using vitamin D supplement compared with the baseline from 341 mg (interquartile range, 90 mg to 757 mg) to 411 mg (interquartile range, 115 mg to 1295 mg; P = .045). Comparing biochemical parameters between the groups who developed 15% and greater and less than 15% increase in urinary calcium showed no significant difference after treatment.The use of vitamin D supplements in conventional dose in patients with vitamin D deficiency may not lead to increased risk of hypercalciuria.

Data collection and the associated automated methods are one of the main building blocks of pavement management systems. One of the main problems associated with automated data collection methods is the high cost of the equipment involved. The aim of this research is to develop a cost-effective system for dense-graded asphalt pavement macrotexture monitoring. To this end, a system based on the tire/road noise, utilizing microphones and employing cepstral signal processing has been developed. The proposed method is compared with the current state of the art PCA based method and is shown that the precision error of the proposed method is about 7%, which outperforms the previous state of the art. To enhance the precision of the cepstral method for the vehicle speed variation amongst the collected dataset, the combination of the cepstral signal processing with Gaussian mixture models is proposed which results in the final precision error of 8%.

Patients with end-stage renal disease (ESRD) are at an increased risk of cardiovas­cular disease due to many factors including inflammation and oxidative stress. N-acetylcysteine (NAC) is a thiol-containing anti-oxidant with anti-inflammatory properties. We aimed to assess the effect of three months treatment with oral NAC on the plasma levels of inflammatory mediators like interleukin-6 (IL-6) and C-reactive protein (hs-CRP) in patients on hemodialysis (HD). Twenty-four patients (nine males and 15 females) on maintenance HD were recruited in the study. Their mean age was 55.3 years. All the patients received oral NAC (600 mg twice a day) for a period of three months. The serum levels of biomedical parameters and IL-6 and hs-CRP were measured at baseline and three months after initiation of treatment. A significant decrease in serum levels of hs-CRP (22.4 vs. 5.2), IL-6 (8.1 vs. 3.6), parathyroid hormone (iPTH) (257.2 vs. 158.8), ferritin (632.0 vs. 515.1) and erythrocyte sedimentation rate (ESR) (54.2 vs. 38.3) was observed following NAC treatment. Female subjects presented with a significantly higher change in serum levels of hs-CRP compared with males (23 vs. 5.4). In three subjects who were less than 40 years old, the hs-CRP and IL-6 levels showed an increase following NAC treatment. Our study found that short-term oral NAC treatment might result in the reduction of IL-6 and hs-CRP in patients who are on regular HD. This suggests that patients with ESRD may benefit from the anti-inflammatory effects of NAC.

The global nephrology community recognises the need for a cohesive plan to address the problem of chronic kidney disease (CKD). In July, 2016, the International Society of Nephrology hosted a CKD summit of more than 85 people with diverse expertise and professional backgrounds from around the globe. The purpose was to identify and prioritise key activities for the next 5-10 years in the domains of clinical care, research, and advocacy and to create an action plan and performance framework based on ten themes: strengthen CKD surveillance; tackle major risk factors for CKD; reduce acute kidney injury-a special risk factor for CKD; enhance understanding of the genetic causes of CKD; establish better diagnostic methods in CKD; improve understanding of the natural course of CKD; assess and implement established treatment options in patients with CKD; improve management of symptoms and complications of CKD; develop novel therapeutic interventions to slow CKD progression and reduce CKD complications; and increase the quantity and quality of clinical trials in CKD. Each group produced a prioritised list of goals, activities, and a set of key deliverable objectives for each of the themes. The intended users of this action plan are clinicians, patients, scientists, industry partners, governments, and advocacy organisations. Implementation of this integrated comprehensive plan will benefit people who are at risk for or affected by CKD worldwide.

Pruritus is a common and bothersome problem in 30-50% of hemodialysis patients. The aim of this study was to determine the effect of gabapentin, 100 mg/three times a week (after each hemodialysis session), on uremic pruritus.Patients older than 18 years who had undergone hemodialysis for more than three months were enrolled in this double-blind clinical trial. They had experienced pruritus refractory to antihistamines for at least two weeks. The patients were assigned to receive gabapentin 100 mg following hemodialysis for a period of four weeks, and after a washout week, they received the placebo for another four weeks. They were asked to evaluate the severity of their pruritus using a visual analogue scale (VAS). The reduction of pruritusor= 50% was accepted as the response.The mean pruritus score reached 6.44 +/- 8.4 (p0.0001), 15 +/- 11.2 (p0.001), and 81.11 +/- 11.07 (p0.001) during gabapentin, washout, and placebo periods, respectively. No significant correlation was found between age, sex, duration of dialysis, underlying diseases, and systolic and diastolic blood pressures and the gabapentin effect.Gabapentin is an effective agent in treating uremic pruritus.

Renal involvement in type 2 diabetes is mostly due to diabetic nephropathy (DN), but a subset of diabetic patients could present with pure non-diabetic renal disease (NDRD) or NDRD superimposed on DN. We conducted a prospective cohort study to identify the underline renal pathology in type 2 diabetic patients with defined clinical criteria for renal biopsy.A total of 46 patients (27 female, mean age of 48.9 ± 11.9 years) with type 2 diabetes mellitus (DM) and atypical features of DN with unexpected proteinuria, hematuria, and/or renal impairment were enrolled in this study.Of 46 patients with type 2 diabetes, 16 (34.8%) had DN, 20 (43.5%) had NDRD, and 10 (21.7%) had NDRD superimposed on DN. Membranous nephropathy (34%) was the most common NDRD. Patients with NDRD had a lower frequency of diabetic retinopathy (5%), shorter duration of diabetes, higher range of proteinuria, and better kidney survival. In multiple logistic regression analysis, only lack of diabetic retinopathy was independent predictor of NDRD. Positive and negative predictive value of diabetic retinopathy (DR) for diabetic nephropathy was 94 and 68%, respectively.Kidney biopsy is strongly recommended for patients with type 2 diabetes and atypical renal presentation for DN, particularly in the absence of DR. This approach could lead to diagnosis of NDRD with better renal survival.

Hemodialysis patients face oxidative stress and inflammation induced by both kidney dysfunction and hemodialysis procedure. These are supposed to be partly responsible for the excessive cardiovascular morbidity and mortality in hemodialysis patients. We investigated the impact of kidney transplantation on the biomarkers of oxidative stress and inflammation.In a prospective cohort study on 32 kidney transplant candidates on hemodialysis, biomarkers of oxidative stress and inflammation were compared before and 3 months after kidney transplantation and were compared with each other as well as their values in the kidney allograft donors as the controls. These biomarkers included total antioxidant capacity, total thiol molecules, lipid peroxidation, plasma catalase, superoxide dismutase, glutathione peroxidase, and C-reactive protein.The mean age of the patients was 38.0 ± 15.5 years. The levels of total antioxidant capacity, total thiol molecules, and activity of glutathione peroxidase were significantly lower and the level of activity of plasma superoxide dismutase was significantly higher in the hemodialysis patients before transplantation as compared to the values for the controls and after transplantation. Lipid peroxidation was significantly higher in the patients before transplantation compared to the controls. A significantly higher level of C-reactive protein was noted in the hemodialysis patients as compared to their levels after transplantation and also C-reactive protein in the controls.These results suggest that oxidative stress and inflammation are elevated in hemodialysis patients which could be improved partly and significantly by restoration of kidney function after kidney transplantation.

Development of delayed graft function is more prevalent in patients receiving a kidney allograft from brain-dead than living donors. This study aimed to evaluate the association between urine neutrophil gelatinase-associated lipocalin (NGAL) levels in brain-dead donors and subsequent allograft function.Urine NGAL concentration was measured in urine samples obtained from 24 brain-dead kidney allograft donors before organ retrieval. The 24 kidney recipients were followed for 6 months. The immunosuppressive therapy was similar for all of the recipients. Following transplantation, plasma creatinine was recorded daily during the recipient's stay in the hospital and then at 1, 3, and 6 months after transplantation. Delayed graft function was defined as the need for dialysis in the first 7 days after transplantation.The mean age of the donors was 28.7 ± 11.2 years and 70.8% were men. Their median urine NGAL level was 7.4 ng/ml (range, 2 ng/mL to 45 ng/mL). Urine NGAL levels were only associated with the need for cardiopulmonary resuscitation (P = .007). On the 1st day after transplantation, 16.7% of the recipients developed delayed graft function, which was declined to 12.5% on the 2nd day and to 8.3% during the 3rd day and the following days. No significant association was observed between the donor's urine NGAL levels and graft function (P = .86).Our results did not show any association between urine NGAL levels and outcome of allograft function obtained from brain-dead donors. Larger studies are required to confirm this finding.

The aim of this study was to assess the prevalence and severity of BK virus infection, BK virus nephritis, and related risk factors among kidney transplant recipients.BK viremia during the first year of kidney transplantation was assessed prospectively in 32 successive recipients. BK virus DNA was extracted and determined in all samples by real-time polymerase reaction assay for 1 year after kidney transplantation.The mean age of the patients was 33.3 ± 15.3 years. Sixteen patients (50%) received antithymocyte globulin for induction therapy. Living donor transplant consisted of 75% of the kidney donations. Maintenance immunosuppressive therapy included cyclosporine A in 27 patients (84.4%), plus tapering prednisolone and mycophenolate mofetil. BK viremia was detected in 8 patients (25%). The highest detected plasma viral load was less than 4000 copies per milliliter. BK virus was respectively positive in 5 (62.5%), 2 (25%), and 1 (12.5%) patients during the first 4, 8, and 12 months after transplantation. Biopsy-proven rejection and antirejection therapy by methylprednisolone pulses were 5 and 2.3 times more common in patients with BK virus infection (P = .01 and P = .01), respectively.Despite occurrence of BK virus infection in 25% of our patients, BK nephropathy did not develop in any of them. Routine screening of BK virus infection, particularly in centers with low prevalence of BK virus nephritis, may not be cost effective for predicting this disease.

Associations between patient survival and baseline urine volume (UV), ultrafiltration (UF) volume, and combined UV and UF were evaluated in Iranian continuous ambulatory peritoneal dialysis (CAPD) patients.From 1995 to 2006, data on 1472 CAPD patients from 26 centers were collected. Demographic, clinical, and laboratory characteristics were analyzed using STATA software. Baseline UV was considered as an indicator of residual renal function and patients with an annual decrease of more than 250 cc/day were placed in decreasing UV group. The role of a new variable, net positive fluid removal, which defines as the combination of baseline UV and UF, was also evaluated.Patients with higher baseline UV were significantly more married and educated and candidate for CAPD based on positive selection criteria. In dichotomous categorization, mean of serum creatinine was lower and albumin was higher in patients with UV ≥ 1000 cc/day compared with UV250 cc/day. A significant correlation was found between baseline UV250 cc/day and ≥1000 cc/day and patient survival. Patients with stable UV had better survival compared with patients with decreasing UV (p = 0.04). There was no correlation between UF and patient survival. Remarkable association with patient and technique survival and net positive fluid removal ≥2000 cc/day and500 cc/day was observed. Multiple Cox regression analysis revealed significant correlation between net positive fluid removal ≥2000 cc/day and higher patient survival [p = 0.01, hazard ratio (HR) = 13.2], higher first albumin (albumin ≥ 3.5 mg/dL, p = 0.01, HR = 0.02), and lower negative selection (p = 0.0001, HR = 11.8).Loss of UV over time and lower net positive fluid removal increase mortality of PD patients.

As an immunosuppressive treatment, cyclosporine carries a significant risk of nephrotoxicity. In this study, we assessed the safety and efficacy of sirolimus conversion in our kidney transplant recipients.Sirolimus conversion in 99 kidney transplant recipients was evaluated. Serum level of creatinine, glomerular filtration rate (GFR), and the occurrence of adverse effects of sirolimus were evaluated at conversion time and 1, 6, 12, 24, and 36 months after conversion.The major causes of conversion were chronic allograft nephropathy and cyclosporine nephrotoxicity. The median time to conversion and follow-up were 54.7 months and 24 months, respectively. Three patients died during the study period. The acute rejection rate was 4%. In 16.6% of the patients, sirolimus was discontinued because of refractory adverse effects. No significant changes in estimated GFR and incidence of adverse effects were observed between patients with baseline estimated GFR lower or higher than 40 mL/min. Patients with early sirolimus conversion (less than 6 months after transplant) had improvement of their GFR (59.9 +/- 22.3 mL/min to 68.0 +/- 15.5 mL/min, P = .02), while kidney recipients with late conversion did not show such an improvement. The difference between GFRs in these two groups reached significant level at 12 months and stayed significant until the end of the follow-up.This study emphasizes that conversion of cyclosporine to sirolimus could be associated with stable kidney allograft function. However, cyclosporine discontinuation should be considered early when it is indicated.

Chronic, progressive, and irreversible loss of a transplanted kidney function, previously named chronic allograft nephropathy, is the leading cause of chronic allograft failure among kidney transplant recipients. Chronic allograft dysfunction (CAD) is a multifactorial process associated with progressive interstitial fibrosis and tubular atrophy. Current Data confirms that an additive series of time-dependent immunological factors such as acute and chronic antibody- and/or cell-mediated rejection and nonimmunological factors are involved in development of interstitial fibrosis and tubular atrophy as the fundamental parts of CAD. The use of calcineurin inhibitors has produced a major impact on achieving successful organ transplantation; however, although this assumption has been doubted recently, calcineurin inhibitors are deemed to be associated with nephrotoxicity and subsequent interstitial fibrosis, tubular atrophy, and kidney dysfunction. The early fibrotic changes are due to implantation stress, T-cell-mediated rejection, and infection; however, usually they do not lead to progressive fibrosis and allograft dysfunction per se. In the setting of CAD, many factors occurring lately after 1 year, such as chronic antibody-mediated rejection, recurrent or de novo glomerulonephritis, and nonadherent adequately address the existence of ongoing injuries and progression to fibrosis. Identification of patients who are at risk, close clinical monitoring, and optimization and individualization of their maintenance immunosuppressive regimen are among the means that could help us to improve the long-term outcome of kidney transplantation.

Chronic kidney disease (CKD) is becoming a major public health problem worldwide. A remarkable part of health budget is designated annually to control end-stage renal disease in most countries. The aim of this study was to screen for CKD among the general population of the rural area of Shahreza, in the central region of Iran.In a study of rural area around Shahreza, Iran, in 2009, a total of 1400 participants aged over 30 years old were selected by systematic randomized sampling. Glomerular filtration rate (GFR) was used as an index of kidney function and albuminuria, as an index of kidney damage. The simplified Modification of Diet in Renal Disease Study equation was used for estimation of GFR.A GFR less than 60 mL/min/m2 was found in 4.7% of the study population (1.8% in men and 6.1% in women). Microalbuminuria and macroalbuminuria were present in 16.2% of the participants (15% of men and 16.8% of women). Pyuria and hematuria rates were 12.3% and 12.6%. The prevalence of a GFR less than 60 mL/min/1.73 m2 was significantly increasing by age groups in both genders.Considering its high prevalence, CKD needs measures to identify the disease sooner and requires an active national screening program to identify patients in earlier stages. It seems reasonable to integrate such programs in the primary healthcare system.

BK virus-associated nephropathy in renal transplant recipients has been increasing in frequency in recent years. This rise is probably because of widespread use of highly potent immunosuppressive regimens, and increased immunosuppression load leads to inability of the recipients to increase a successful antiviral immune response. The incidence of BK virus-associated nephropathy in different reports is between 1% and 10%, with an allograft loss in significant numbers of patients, especially when timely diagnosis and treatment is not restored. We report our experience on BK virus nephropathy in our institute.All renal transplant biopsies performed at our center between 2001 and 2006 were immunohistochemically screened for the presence of PV-specific protein (SV40 Ag). The histologic diagnosis of BK virus-associated nephropathy was made upon the observation of morphologic changes in tubular epithelium and confirmation with immunohistochemical staining. We reviewed the clinical records of the subjects for demographic, clinical, and laboratory data.BK virus nephropathy was found in 0.93% of all investigated allograft biopsies (1/108) and in 1.04% of all recipients (1/96; mean age of recipients, 36.48±14.10 years; age range, 13-74 years); 54 of them were male (57%). Type of kidney transplant was living-unrelated donor 76 (79%), living-related donor 13 (14%), and deceased donor 7. Seventeen patients (18%) were transplanted for a second time. Immunosuppressive drugs in 87 of recipients (90%) were cyclosporine, mycophenolate mofetil, and prednisolone. Our patient who developed BK virus-associated nephropathy 9 months after transplant was a 37-year-old man on prednisone, cyclosporine, and azathioprine immunosuppresion. He lost his graft 4 months after diagnosis.Although BK virus nephropathy after renal transplant is uncommon, it is a serious complication causing loss of the allograft. It should be included in the clinical differential diagnosis of transplant dysfunction.

Culture-negative peritonitis is a major challenge in the treatment of peritonitis in continuous ambulatory peritoneal dialysis (CAPD). This study aimed to evaluate the culture-negative peritonitis in patients from the Iranian CAPD Registry.Data of 1472 patients from 26 CAPD centers were analysed. Peritonitis was defined as any clinical suspicion together with peritoneal leukocyte count of 100/mL and more.The patients had been on PD for a mean of 500 ± 402 days. There were a total of 660 episodes of peritonitis observed among 299 patients (peritonitis rate of 1 episode in 34.1 patient-months). Excluding patients with both negative and positive culture results, there were 391 episodes of peritonitis in 220 patients (174 culture-positive episodes in 97 patients and 217 culture-negative episodes in 123). The 1- to 4-year patient survival rates were 85%, 75%, 69%, and 59% for the patients with culture-positive peritonitis, and 92%, 78%, 73% and 63% for the patients with culture-negative peritonitis, respectively (P = .34). The technique survival rates were 90%, 57%, 42%, and 27% and 95%, 85%, 74%, and 40%, respectively (P = .001). On follow-up, there were higher rates of active PD patients, lower rates of PD dropouts, and higher rates of kidney transplantation in patients with culture-negative peritonitis compared to those with culture-positive peritonitis.In our patients, the prevalence of culture-negative peritonitis was high (55.9%). Patient survival with culture-negative peritonitis was comparable to those with culture-positive peritonitis and technique survival was higher among those with culture-negative peritonitis.

Many factors have been proposed to be associated with higher mortality in patients on continuous ambulatory peritoneal dialysis (CAPD). However, the relative importance of these factors may differ among patients with different characteristics. We evaluated survival of patients on CAPD and its influencing factors in Iran.We enrolled 282 patients on CAPD between 1996 and 2006 at 2 major CAPD centers in Tehran. Patient survival was investigated during this period. Demographic characteristics, laboratory data, dialysis adequacy parameters, residual renal function, peritoneal transport characteristics, and nutritional status were assessed as potential predictors of the outcome.The mean duration of follow-up was 18.4 +/- 14.5 months. Sixty patients (21%) died during the studied period. In univariate analysis, age, body mass index, history and duration of hemodialysis before CAPD, diabetes mellitus, blood pressure, patient selection criteria, edema, peritonitis, renal residual function, urine volume, dialysis adequacy, and serum levels of cholesterol, triglyceride, intact parathyroid hormone, calcium, and albumin were predictors of patient survival. Multivariate analysis demonstrated that old age, diabetes mellitus, prior hemodialysis longer than 7 months, low serum albumin, calcium, trigelyceride, and parathyroid hormone levels independently predicted mortality, while the use of angiotensin-converting enzyme inhibitors was associated with a better survival.This study showed that older patients on CAPD and diabetics are at a higher risk of mortality. On the other hand, nutritional and metabolic factors are other predictors of mortality. Especial concern should be applied to good nutrition and treatment of comorbidities in these patients.

PDpoietin is a recombinant erythropoietin alfa that has been introduced by a manufacturer in Iran. We assessed the effectiveness and complications of PDpoietin in comparison with Eprex in anemic patients on hemodialysis.This clinical trial was performed in a multicenter setting. Patients with a hemoglobin level less than 12 g/dL were assigned into 2 groups in order to receive either Eprex (Janssen Cilag) or PDpoietin (Pooyesh Darou) for 3 months.Forty-one and 34 patients completed the study in the PDpoietin and Eprex groups, respectively. The mean hemoglobin levels at baseline were not significantly different between the two groups of patients with PDpoietin and Eprex. In both groups, hemoglobin levels increased significantly, but there were no significant differences between the two groups at months 1, 2, and 3. At the end of the study, the mean hemoglobin levels reached 11.6 +/- 1.7 g/dL and 11.8 +/- 1.9 g/dL, respectively (P = .002; P = .01). The mean hemoglobin per cumulative of drug dose index (hemoglobin/[erythropoietin dose/1000 x injections per month]) was not significantly different between the two groups at different treatment stages, and it did not change significantly in each group during the course of the study. No serious complications were reported.Eprex and PDpoietin could equally increase the hemoglobin levels with no significant complication. Therefore, PD can be used for treatment of anemia in patients on dialysis, and the patients will have the advantages of its availability and low price.

The incidence of acute rejection of the kidney allograft in the world has been around 15% during the period between 2001 and 2003. It is clinically defined as an elevation in the level of serum creatinine by more than 0.3 mg/dL and is diagnosed by kidney biopsy. On pathologic examination, the interstitium of the allograft is diffusely edematous and infiltrated by CD4 and CD8 lymphocytes. Tubulitis occurs when the lymphocytes and monocytes extend into the walls and lumina of the tubules. Presence of leukocytes determines infection or antibody-mediated rejection. Typically C4d staining is negative. Other causes of acute allograft dysfunction included prerenal factors, interstitial nephritis, infection, acute tubular necrosis, toxicity by drugs, and obstruction in the urinary tract. The primary diagnostic assessments include history, especially adherence to immunosuppressive therapy, physical examination, blood and urine laboratory tests, measurement of the serum levels of the drugs, and ultrasonography. Diagnosis of acute cellular rejection depends on biopsy, CD20 staining for refractory cases, negative C4d staining, presence of markers of activating lymphocyte, and proteomic study. Treatment of acute cellular rejection in kidney transplant recipients include pulse steroid for the first rejection episode. It can be repeated for recurrent or resistant rejection. Thymoglobulin and OKT3 are used as the second line of treatment if graft function is deteriorating. Changing the protocol from cyclosporine to tacrolimus or adding mycophenolate mofetil or sirolimus might be effective. Prognosis depends on number of rejection episodes, the use of potent drugs, time of rejection from transplantation, and response to treatment.

Sirs, Involvement of the peripheral nervous system in Henoch– Schonlein purpura (HSP) is rare [1]. Here, we introduce the reader to an uncommon neural manifestation of HSP in the lower limb. A 15-year-old boy presented at the emergency room of a hospital in Divan dare, a small city in the west of Iran, with abdominal pain, fever, bloody diarrhea and melena, arthralgia (both knees and elbows), gross hematuria, and palpable purpura on the buttock and behind the thigh. He was diagnosed with HSP and was treated with prednisolone 30 mg/day, which was reduced to 10 mg/day upon his discharge. He was admitted for 6 days, and, when he was discharged, the skin lesions had improved. Two weeks later, the patient developed a right-side incomplete foot-drop, which brought him to our center, Shariati Hospital. On his admission, hematuria and facial edema were observed. Physical examinations were not revealing, except for impaired dorsal flexion of the right ankle. Para-clinical findings were consistent with HSP: proteinuria (3,900 mg/24 h), and normal levels of C3, C4, and CH50. Results of tests for viral markers [hepatitis B virus (HBV), hepatitis C virus (HCV), and human immunodeficiency virus (HIV)], antinuclear antibodies (ANAs), cytoplasmic anti-neutrophilic cytoplasmic antibodies (C-ANCAs,) perinuclear anti-neutrophilic cytoplasmic antibodies (P-ANCAs) and cryoglobulin were negative. Serum level of immunoglobulin A (IgA) was 218 mg/dl (normal range 70–400 mg/dl). Ultrasonic evaluations of the urinary tract showed normal findings, except for increased cortical echogenicity of both kidneys. Histopathologic assessment of the renal biopsy showed diffuse mesangio-proliferative lesion with focal endocapillary proliferation and cellular crescents in 15% of the glomeruli. Immuno-fluorescence studies demonstrated IgA (2+) and C3 (1+) depositions in the mesangium. Electromyography and nerve conduction velocity (EMG/NCV) suggested mononeuropathy of the right deep proneal nerve, but, because the patient was unwilling, neural biopsy was avoided. Though not proven pathologically, the cause of the dropped foot was assigned to the underlying HSP, and an aggressive therapeutic strategy was adopted: intravenous administration of methylprednisolone (500 mg; three doses) and cyclophosphamide (750 mg), followed by oral treatment with prednisolone 15mg/day, which was increased to 40 mg/day (1 mg/kg) upon his discharge. Impaired dorsiflexion started to improve after 1 week from the beginning of the treatment. Although the patient received cyclophosphamide pulses monthly for three times, the hematuria relapsed when it was discontinued. With prescription of azathiopurine (100 mg/day) as an alternative, renal activity of HSP subsided again. Now, the patient has trace hematuria without proteinuria, and the foot drop has improved completely. The clinical feature of our patient was completely compatible with HSP. Although other vasculitis, especially microscopic polyarteritis nodosa (PAN), was demonstrated as differential diagnosis, the result of the renal biopsy, which showed mesangial deposition of IgA, confirmed the diagnosis [1]. Headaches and changes in mental status are the most frequent neurologic complications of HSP, followed by seizures, focal neurologic deficits, mononeuropathies, and polyradiculoneuropathies [2]. By reviewing the literature we found three reports of an association of HSP with manifestations of the peripheral nervous system (PNS), including involvement of the posterior tibial nerve Pediatr Nephrol DOI 10.1007/s00467-008-0952-5

Background Pruritus is one of the most bothersome symptoms in patients on maintenance hemodialysis (HD), however little progress is seen in our understanding of its pathogenesis. The aim of this study was to evaluate the frequency of pruritus in HD patients in Tehran, Iran, and to correlate its presence and intensity with relevant clinical and laboratory parameters. Methods One hundred sixty-seven patients on maintenance HD at three out-patient HD units were enrolled in the study. Itch intensity was scored as mild, moderate and severe. Some relevant clinical and laboratory parameters (age, sex, xerosis, presence of neuropathy, duration of dialysis, history of atopy and laboratory findings including hematocrit, creatinine, urea, calcium, phosphorus, parathyroid hormone [PTH] and alkaline phosphatase) were evaluated. Results Pruritus was found in 41.9% of patients. The intensity of itching was mild, moderate and severe, in 51.4%, 11.4% and 37.7% of patients, respectively. In 22 patients (31.4%) pruritus intensified during and after dialysis. There was no significant difference in the serum levels of creatinine, blood urea nitrogen, calcium, phosphorus, alkaline phosphatase, PTH and hematocrit between patients with and without pruritus. Age, sex, xerosis, underlying renal disease, history of atopy and duration of haemodialysis were not significantly different between the two groups. However, neuropathy was significantly more common in the pruritic group (63.8% versus 42.1%) (pv = 0.006). Conclusion Clinical neuropathy was the only significant finding in the pruritic group in our study. This finding justifies further research on nerve function and neurotransmitters in hemodialysis patients and the introduction of new drugs targeting neuropathy.