Showing papers in "International Urology and Nephrology in 2010"

NGAL: a biomarker of acute kidney injury and other systemic conditions.

Abstract: Neutrophil gelatinase-associated lipocalin (NGAL) is a 25 kDa protein belonging to the lipocalin superfamily. It was initially found in activated neutrophils, however, many other cells, like kidney tubular cells, may produce NGAL in response to various insults. Recently, it has been found to have a role in iron metabolism by virtue of its binding with siderophores. It has also been found to have a role in kidney development and tubular regeneration after injury. In experimental studies, it was found to be highly expressed in response to tubular injury. In subsequent clinical studies, urine NGAL has been found to be an early predictor for acute kidney injury (AKI). Newer devices for early bedside detection of NGAL are now available. Since serum creatinine is known to be an inadequate and late marker of AKI, NGAL might soon emerge as a troponin-like early marker for AKI. Recent evidence also suggests its role as a biomarker in a variety of other renal and non-renal conditions.

Urine cytokines suggest an inflammatory response in the overactive bladder: a pilot study.

Abstract: To study the hypothesis of detecting bladder inflammation associated with overactive bladder (OAB) through altered urine levels of cytokines, chemokines, and growth factors. Midstream urine specimens were collected from a prospective study done on eight asymptomatic control subjects and 17 idiopathic OAB patients. The urine was analyzed by a multiplex panel screen for 12 chemokines, cytokines, growth factors, and soluble receptors using Luminex™ xMAP® technology. Protein concentration values were normalized to the levels of creatinine. This analysis revealed a significant elevation of seven key proteins in the urine of OAB patients relative to controls (*P < 0.05). A greater than tenfold elevation was measured in OAB, relative to controls, in the levels of monocyte chemotactic protein-1 (MCP-1), soluble fraction of the CD40 ligand (sCD40L) in urine was obtained from OAB patients relative to controls. At least five fold elevations were detected in the levels of macrophage inflammatory protein (MIP-1β), IL-12p70/p40, IL-5, epidermal growth factor (EGF), and growth-related oncogene GRO-α compared to controls. Significant threefold elevation was also noticed in the urine levels of sIL-2Rα, and IL-10 in the OAB group. The levels of the remaining proteins tested were not statistically significantly different from control values. The presence of elevated levels in urine of inflammatory biomarkers involved in inflammation and tissue repair suggests a role for inflammation in OAB, and may help in diagnosis and treatment of this disease.

Up-regulation of microRNA in bladder tumor tissue is not common

Abstract: MicroRNAs (miRNAs) have recently been shown to down-regulate gene expression by targeting mRNA translation and to play a critical role in tumorigenesis; how they regulate bladder tumor development, particularly in patients, is, however, poorly understood. The difference in miRNA expression in a bladder tumor compared with healthy tissue from the same patients was examined using microRNA arrays in seven patients. Here, we showed that up-regulation of miRNA was not commonly found in this limited number of patients, and four miRNAs (miR-26a, miR-29c, miR-30c, miR-30e-5p) were down-regulated as a common marker in patients with a 1-3 grade of disease. Our data suggest that instead of up-regulation of carcinogenic miRNAs, loss of regulation of these miRNA may be critical for bladder tumor development in patients.

The comparative study of serum iron, copper, and zinc levels between bladder cancer patients and a control group.

Abstract: A relatively wide range of trace elements are known to play important roles in biological processes, including the oxidative processes. Oxidative processes are one of the mechanisms involved in both incidence and recurrence of bladder cancer. In the present study, the concentration of iron (Fe), copper (Cu) and zinc (Zn) were determined in the serum of patients with bladder cancer in comparison to healthy subjects. This cross-sectional study was conducted on 51 patients with bladder cancer and 58 healthy volunteers after age, sex, and smoking habits were matched. After overnight fasting, samples were collected. The concentrations of Fe, Cu, and Zn were measured by flame atomic absorption spectroscopy and comparisons were made using Student's t-test. There was a significant increase in mean Cu and Cu/Zn serum level in bladder cancer patients compared to the control group (P < 0.001). In contrast, the serum zinc level in patients having bladder cancer was significantly lower than in the control group (P < 0.05). Moreover, the serum iron level was significantly lower in the patients than the control group (P < 0.001). In the present study, a relationship was seen between the level of trace elements and the occurrence of bladder cancer, suggesting that an increase in the serum level of Cu and a decrease in the levels of Zn and Fe might be important causes of bladder cancer occurrence; however, defining such a cause-and-effect relationship needs several prospective studies to be done, which seems necessary with regard to the high prevalence of this cancer.

Internal urethrotomy and intraurethral submucosal injection of triamcinolone in short bulbar urethral strictures

Abstract: Objectives In clinical practice, internal urethrotomy is an easy procedure and is offered as a first modality for treatment of short urethral strictures Internal urethrotomy refers to any procedure that opens the stricture by incising or ablating it transurethrally The most common complication of internal urethrotomy is stricture recurrence The curative success rate of internal urethrotomy is approximately 20% Triamcinolone has antifibroblast and anticollagen properties This study evaluated the efficacy of triamcinolone in the prevention of anterior urethral stricture recurrence after internal urethrotomy

No advantage is gained by preoperative bowel preparation in radical cystectomy and ileal conduit: a randomized controlled trial of 86 patients.

Abstract: Objective Bowel preparation (BP) is performed routinely before intestinal surgery to reduce the risk of postoperative infectious complications. We studied the effect of BP on patients who underwent radical cystectomy and ileal conduit surgery. Our goal was to determine whether BP in these patients provided any benefits postoperatively.

The relationship between chronic volume overload and elevated blood pressure in hemodialysis patients: use of bioimpedance provides a different perspective from echocardiography and biomarker methodologies.

Abstract: Chronic volume overload is very frequent in hemodialysis (HD) patients and is directly associated with hypertension, increased arterial stiffness, left ventricular hypertrophy (LVH), heart failure and ultimately with higher mortality and morbidity. One major issue is that presently there are very few comparative studies of the various methods (clinical, bioimpedance, inferior cava vein diameter (ICV) and Brain Natriuretic Peptide (NT-proBNP)) for volume status evaluation and their correlation with cardiovascular disease. In 160 patients treated by chronic HD in our center, euvolemic according to clinical assessment, we performed evaluation of volume status through bioimpedance spectroscopy (BIS), ICV and NT-proBNP, as well as echocardiography, to estimate the left ventricle structure and function. Despite appearing clinically euvolemic, severe fluid overload, as defined by a relative tissue hydration (RTH)—i.e. fluid overload over extracellular water ratio (FO/ECW)—above 15% was found in 25.6% of patients. Four categories of patients were considered according to pre-HD BP and BIS values. Forty-five percent of patients (group A) had a reasonable control of BP and volume (SBP 150 mmHg and RTH 150 mmHg and RTH > 15%), while 9% (group D) had SBP 15%. Assuming that BIS is the most accurate and validated method to assess hydration status, we calculated the positive predictive value for ICV-based evaluation—18%, with a sensitivity of 67% and an important proportion of false negative cases (45%). NT-proBNP was even less accurate: PPV of only 26%, with a sensitivity of 60% and a specificity of only 45% and an extremely high proportion of false positive cases (73%). Group A patients had the best cardio-vascular profile: lowest LV mass and NT-proBNP levels. Using multi-frequency body impedance spectroscopy, we found a large group of hypertensive and/or fluid-overloaded patients despite apparently being at “dry weight” on clinical evaluation and a marked discrepancy between clinical appearance and fluid status. Of the 4 different methods, assuming BCM “gold standard”, there were major disagreements and discrepancies between the other three methodologies. BCM is a valuable and simple bed-side tool for the correct management of BP and risk stratification in HD patients as it allows for excellent discriminators of more abnormal cardiac and vascular profiles.

Exercise program to enhance physical performance and quality of life of older hemodialysis patients: a feasibility study.

Abstract: Objective Evaluate the feasibility of implementing a combined in-hospital and home-based exercise program in older hemodialysis (HD) patients. Design A prospective longitudinal 12-week pilot study. Setting A university hospital HD unit and patients’ homes.

Progression of aortic arch calcification and all-cause and cardiovascular mortality in chronic hemodialysis patients

Abstract: Objective Although aortic arch calcification (AoAC) is reported as a predictor for cardiovascular mortality in the general population, it is unknown whether this is also true in hemodialysis (HD) patients in whom vascular calcification and cardiovascular diseases are highly prevalent.

Sertraline treatment is associated with an improvement in depression and health-related quality of life in chronic peritoneal dialysis patients

Abstract: There is scarce data about effects of treatment of clinical depression in peritoneal dialysis (PD) population. We aimed to determine prevalence of depression, its association with health-related quality of life (HRQoL) and effects of sertraline treatment in PD patients. We included 124 PD patients who had been on PD at least for 6 months. Short Form of Medical Outcomes Study was used to evaluate HRQoL. Depression was screened by Beck Depression Inventory (BDI). Patients with a BDI score ≥17 were deemed to have depression and were referred to a psychiatrist for evaluation via Diagnostic and Statistical Manual for Mental Disorders (DSM-IV) of diagnosis of clinical depression. About 25 patients diagnosed with clinical depression agreed to receive antidepressant treatment (Sertraline hydrochloride, 50 mg/day) for a 12-week period. After the treatment, biochemical analyses and questionnaires were repeated. Thirty-two patients (25.8%) had depression. BDI score of patients were lower compared to those without depressive symptoms (23 ± 6.7 and 9.8 ± 3.0, respectively P < 0.001). Physical component scale (PCS) and mental component scale (MCS) domains of HRQoL were significantly decreased in patients with depression than in patients without depression (P < 0.001 for PCS and MCS). In bivariate analysis the BDI score was correlated inversely with the PCS and MCS (P < 0.001). Sertraline treatment improved BDI score of patients with depression (P < 0.001). HRQoL parameters also improved. No adverse effects requiring drug cessation was seen in the study group. Treatment of depression with sertraline is associated with improvement of the HRQoL and symptoms related to depression.

Arterial stiffness in dialysis patients: where are we now?

Abstract: Patients with end-stage renal disease treated by chronic dialysis have an impressive mortality, which more than half of this mortality is attributable to cardiovascular disease. Despite stratification for sex, race, and the presence of diabetes, cardiovascular disease mortality is 10–30 times higher in dialysis patients compared to general population. In dialysis patients, both atherosclerosis (mainly affecting the intima of the arteries) and arteriosclerosis (affecting predominantly the media of large- and middle-sized arteries diffusely) are highly prominent. Arteriosclerosis characterized by reduced arterial compliance (i.e., reduced elasticity of the arteries) is due to increased fibrosis, loss of elastic fibers, and extensive vessel wall calcification. Arteriosclerosis is closely related to arterial stiffness. A generally accepted mechanistic view is that an increase in arterial stiffness causes a premature return of reflected waves in late systole, increasing central pulse pressure, thus systolic. An increased arterial stiffness can increase the risk of stroke through several mechanisms, including an increase in central pulse pressure, influencing arterial remodeling both at the site of the extracranial and intracranial arteries, increasing carotid wall thickness, and the development of stenosis and plaques, and the likelihood of plaque rupture. Very importantly, it was also suggested that arterial stiffness itself independently plays a role in exacerbating chronic kidney disease progression. This review deals briefly with the definition of arterial stiffness, methods of measuring arterial stiffness and pathophysiology of arterial stiffness, and factors related with arterial stiffness.

Gonadal dysfunction and infertility in kidney transplant patients receiving sirolimus

Abstract: Sirolimus is an immunosupressor of the mammalian target of rapamycin inhibitors (mTOR-I) group. Recent studies have emphasized a potential impact of sirolimus on male gonadal function. We report our clinical experience with sirolimus-induced gonadal dysfunction and infertility in both male and female kidney transplant patients. Of the 170 kidney transplant patients, nine (5.3%) patients (six males and three females) were receiving sirolimus. Follow-up data for two male patients were not available. The one unmarried female patient developed amenorrhea post-transplantation and had resumption of her menstrual cycles after discontinuation of sirolimus. The remaining six married patients (four males and two females), who all had fathered or conceived children in the pre-transplantation period, developed gonadal dysfunction and infertility on average 5–12 months after transplantation. Sirolimus was discontinued in all four male patients with full recovery of the oligo/azospermia and restoration of fertility. Both married female patients developed amenorrhea post-transplantation. Sirolimus was discontinued in one female patient with resumption of her menstrual cycles. In this small population of patients treated with sirolimus, the prevalence rate of reversible gonadal dysfunction and infertility was significant in both males and females. Infertility secondary to sirolimus is under-diagnosed and should be studied further.

Impact of heart failure on the incidence of contrast-induced nephropathy in patients with chronic kidney disease.

Abstract: We randomized patients with chronic kidney disease (serum creatinine ≥ 1.5 mg/dl or glomerular filtration rate (GFR) <60 ml/min/1.73 m²) in a double-blind fashion to receive saline or sodium bicarbonate prior to and after cardiac or vascular angiography. The primary endpoint was contrast-induced nephropathy (CIN), defined as an increase in serum creatinine by 25% or by 0.5 mg/dl from baseline. Patients with congestive heart failure (CHF), cardiac ejection fraction (EF) <30%, or GFR < 20 ml/min/1.73 m² were excluded. The study was discontinued (after 142 patients were randomized) due to a low incidence of CIN (1.5%). We retrospectively identified all cases of CIN (n = 30) at our institution during the same time period to see if these patients differed from our trial sample. There was no difference in serum creatinine (1.7 ± 0.4 vs. 1.7 ± 0.6 mg/dL), GFR (42.7 ± 9.7 vs. 45.3 ± 3.2 ml/min), incidence of diabetes (51.8% vs. 63.3%), contrast volume (121.7 ± 63.8 vs. 122.7 ± 68.3 ml), ACE inhibitor or angiotensin receptor blocker use (54.0% vs 63.3%), and periprocedure diuretic use (33.1% vs 26.7%). On multivariate analysis, only a cardiac ejection fraction (EF) of less than 40% was significantly associated with CIN (odds ratio, 4.52; 95% confidence interval, 1.30–15.71; P = 0.02). In all, 22/30 patients (73.3%) who developed CIN had at least one or more characteristics that would have excluded their enrollment in our randomized trial including evidence of congestive heart failure (17/30 patients), EF less than 30% (9 patients), age greater than 85 years (2 patients), or advanced renal failure with a baseline GFR of less than 20 cc/min (1 patient). In summary, patients with CKD without evidence of CHF who receive adequate hydration appear to have a very low risk of CIN associated with angiography. A low EF (less than 40%) appeared to be the most significant risk factor for CIN in our population.

Acute tubular necrosis and pre-renal acute kidney injury: utility of urine microscopy in their evaluation- a systematic review

Abstract: Background Urine microscopy with examination of the urine sediment examination provides useful diagnostic information about the histology of the kidneys. While most nephrologists use urine microscopy to assess for the presence of glomerular diseases, they are less apt to use this diagnostic test when pre-renal acute kidney injury (AKI) or acute tubular necrosis (ATN) is clinically suspected. More often, tests such as fractional excretion of sodium (FeNa) and fractional excretion of urea (FeUrea) are used to differentiate these two causes of acute kidney injury.

Dialysis modality choices among chronic kidney disease patients: identifying the gaps to support patients on home-based therapies

Abstract: Home dialysis is a cost-effective renal replacement strategy, which provides improved quality of life compared to conventional in-center hemodialysis (CHD). To date, most studies support the use of multidisciplinary chronic kidney disease (CKD) clinics to facilitate timely initiation of dialysis. This is an observational cohort study examining 486 patients with CKD over the period of 2001–2007 to ascertain potential demographic differences among patients transitioned to in-center versus home dialysis. From January 2001 to December 2007, 486 patients with CKD attended the multidisciplinary renal management clinic at the University Health Network in Toronto. One hundred and fifty-three of the 486 patients were initiated on renal replacement therapy [59 to center hemodialysis (CHD), 15 to home hemodialysis (HHD) and 79 to home peritoneal dialysis (PD)]. HHD patients were younger (48 ± 15 years) than those who selected CHD (62 ± 16 years) or PD (64 ± 16 years). Although the gender distribution was similar overall, the percentage of single males was higher in CHD versus home dialysis patients (29 vs. 15%, P < 0.05). There were no significant differences in other demographic, clinical and biochemical parameters at the time of dialysis initiation. Disinterest in home dialysis by patients and their families (25.4%) and lack of social support (12.1%) constituted the main barriers to home dialysis. Medical contraindications for home dialysis were present among 11% of the patients. Other less frequent barriers were inadequate space, communication barrier and inability to perform their own dialysis. Sixty-one percent of patients requiring dialysis chose a home dialysis modality. Patients’ and their families’ disinterest in home dialysis and lack of support (either perceived or actual) represented the major overall barriers to adoption of home dialysis.

Clinical and metabolic risk factor evaluation in young adults with kidney stones

Abstract: The most frequent urine metabolic risk factor in adults is idiopathic hypercalciuria while in children is hypocitraturia. If there is really a change of metabolic abnormalities with age it would be interesting to study risk factors in the intermediate population: young adults. We evaluated metabolic risk factors, clinical presentation and family history of stone formers between 17 and 27 years old. A total of 160 patients (87 males and 73 females) were studied with a standard protocol. A single urine metabolic risk factor was present in 64% of the patients, and multiple risk factors were present in 27% of them. No metabolic abnormalities were found in the remaining 9%. The most common urine risk factor was idiopathic hypercalciuria (alone or in combination), which was identified in 42.5% followed by hypocitraturia (alone or in combination) found in 32.9% of the patients. In the subgroup of patients of 17–20 years (n = 75; mean age of 18.8 ± 1.0 years), hypocitraturia (alone or in combination) was as frequent as idiopathic hypercalciuria (alone or in combination), which was identified in 38% (n = 30) and 36.7% (n = 29), respectively. The most frequent form of presentation was renal colic (72%). A positive family history of stone disease in first degree and second-degree relatives was found in 32.9 and 34.1%, respectively. Metabolic abnormalities were found in 91% of young adults with renal lithiasis, similar to our adult series. Hypercalciuria was the most frequent metabolic abnormality found. Yet, hypocitraturia (alone or in combination) was very frequent, and in the subgroup of patients of 17–20 years, it was as frequent as idiopathic hypercalciuria, similar to what we found in children.

The significance of age on success of surgery for patients with varicocele.

Abstract: The aim of our study was to assess the impact of patient age on sperm characteristics, and hormonal levels following varicocelectomy. We retrospectively reviewed the clinical records of 96 patients with a mean age of 28.1 years (range 18–48), who underwent microsurgical subinguinal varicocelectomy because of infertility, palpable swelling, or scrotal pain. These groups of patients were categorized into three age groups: group I, 18–25 years old at the time of varicocelectomy (n = 35 [36.5%]); group II, 26–35 years old (n = 43 [44.8%]); and group III, older than 36 years (n = 18 [18.8%]). Of the 96 patients, 68 attended the initial postoperative visit at 1 month and 96 attended the 6 months follow-up visit. Before surgery, no significant differences were seen among the three groups in sperm concentration, sperm motility and hormonal levels. After ligation, the sperm concentration and motility rates increased in all groups, but no significant differences were seen among the three groups for those parameters (P = 0.235 and P = 0.729, respectively). However, no significant changes in follicle-stimulating hormone, LH, testosterone levels were observed between each group. At sixth month of follow-up, two patients in group II, and a patient in group III, had persistent scrotal pain, and a patient in group I had varicocele recurrence; but no patients had hydrocele formation, evidence of testicular loss or progressive hypotrophy. The results of our study have shown that age is not a significant factor for outcomes of surgery and subinguinal microsurgical varicocelectomy in all aged patients has a similar high success rates.

Evaluation of relationship between HIF-1α immunoreactivity and stage, grade, angiogenic profile and proliferative index in bladder urothelial carcinomas

Abstract: Hypoxia-inducible factor-1α (HIF-1α) is a critical regulatory protein of cellular response to hypoxia. In this study, we evaluated the relationship of HIF-1α with clinicopathologic parameters such as tumor stage and grade, as well as angiogenic profile and proliferation index. The immunoreactivity of HIF-1α was assessed in 70 cases of primary bladder urothelial carcinoma. Vascular endothelial growth factor (VEGF) and microvessel density (MVD) were used to evaluate the angiogenic profile. MVD was calculated by immunohistochemical staining of endothelial cells with CD34. Proliferation index was determined by the percentage of Ki-67 nuclear staining in tumor cells. There was a significant relationship between HIF-1α immunoreactivity and stage, as well as histologic grade of the tumor (P < 0.001). HIF-1α immunoreactivity was also closely related to VEGF expression (P < 0.001), MVD (P = 0.002) and proliferation index (P < 0.001). VEGF, MVD and proliferation index were found to be closely related to tumor stage and histologic grade. There was no correlation between HIF-1α immunoreactivity and lamina propria (P = 0.13), muscularis propria (P = 0.009) or vascular invasion (P = 0.1). In this study, HIF-1α expression was found to be closely related to prognostic parameters in bladder urothelial carcinoma. For this reason, it may be a useful marker to determine the prognosis and to choose the appropriate treatment modality.

Paricalcitol reduces basal and lipopolysaccharide-induced (LPS) TNF-α and IL-8 production by human peripheral blood mononuclear cells

Abstract: Vitamin D and its analogues proved to exert immunomodulatory effects. Paricalcitol is a vitamin D analogue that is safe. It has been used for years in the treatment of secondary hyperparathyroidism in hemodialysis patients and, importantly, it is less calcemic than vitamin D. In this study the immunomodulatory/anti-inflammatory properties of paricalcitol were evaluated in vitro. Ten healthy volunteers enrolled into the study. Peripheral blood mononuclear cells (PBMC) at a concentration of 106 cells per well were cultured for 48 h in the presence or not of lipopolysaccharide (LPS) (100 ng/ml) and in the presence or not of paricalcitol (10−8 M). TNF-α and IL-8 were measured in the supernatants by ELISA. Basal TNF-α concentration (50.3 ± 22 pg/ml) was reduced by paricalcitol (44.1 ± 23.2 pg/ml). LPS increased TNF-α concentration (150.0 ± 81.7 pg/ml), but paricalcitol reduced it (121.1 ± 69.0 pg/ml). The effect of paricalcitol on IL-8 production was more profound. Basal IL-8 concentration (1926 ± 455 pg/ml) was reduced by paricalcitol (1273 ± 472 pg/ml). LPS increased IL-8 concentration (2361 ± 385 pg/ml), but paricalcitol returned it to its basal level (1849 ± 417 pg/ml). The in vitro inhibition of transforming growth factor alpha and interleukin 8 by paricalcitol confirms the immunomodulatory properties of this vitamin D analogue.

Hyperoxaluria after modern bariatric surgery: case series and literature review

Abstract: Introduction Two recent studies have shown that modern bariatric surgery leads to significant hyperoxaluria and risk of nephrolithiasis. However, neither report evaluates the use or effects of stone risk modifying agents in these patients. We sought to determine the impact of medical management on stone risk profile in patients who have undergone Roux-en-y gastric bypass.

Urethral diverticular carcinoma: an overview of current trends in diagnosis and management

Abstract: Aims To review the management of female urethral diverticular tumours, and rationalize treatment protocols.

A right renal angiomyolipoma with IVC thrombus and pulmonary embolism.

Abstract: Angiomyolipomas (AML) are benign lesions, commonly found in the kidney, where they may be single or multiple. There is a high association with tuberous sclerosis or lymphangioleiomyomatosis. When found as a solitary lesion, they are usually found in females in the forties to fifties age group. One of the rare complications is that of involvement of the lymph nodes and vascular spread via the inferior vena cava. We review the available literature and present a case of invasive AML with fat embolism.

Depressive symptoms and chronic kidney disease: Results from the National Health and Nutrition Examination Survey (NHANES) 2005-2006

Abstract: Background and objective Depression is common in individuals with end-stage renal disease. However, its relationship with earlier stages of chronic kidney disease (CKD) is less well known. In this study, we examined the association between depressive symptoms and CKD.

A comparative study to evaluate the effect of double dartos flaps in primary hypospadias repair: no fistula anymore

Abstract: Purpose The aim of this study was to compare the complication rates of the single flap and double flaps versus flapless procedure in the tubularized incised plate urethroplasty.

Late diagnosis of primary hyperoxaluria after failed kidney transplantation

Abstract: Primary hyperoxaluria type 1 (PH1) is a rare autosomal recessive inborn error of the glyoxylate metabolism that is based on absence, deficiency or mislocalization of the liver-specific peroxisomal enzyme alanine:glyoxylate aminotransferase. Hyperoxaluria leads to recurrent formation of calculi and/or nephrocalcinosis and often early end-stage renal disease (ESRD) accompanied by systemic calcium oxalate crystal deposition. In this report, we describe an adult female patient with only one stone passage before development of ESRD. With unknown diagnosis of PH, the patient received an isolated kidney graft and developed an early onset of graft failure. Although initially presumed as an acute rejection, the biopsy revealed calcium oxalate crystals, which then raised a suspicion of primary hyperoxaluria. The diagnosis was later confirmed by hyperoxaluria, elevated plasma oxalate levels and mutation of the AGXT gene, showing the patient to be compound heterozygous for the c.33_34InsC and c.508G > A mutations. Plasma oxalate levels did not decrease after high-dose pyridoxine treatment. Based on this case report, we would recommend in all patients even with a minor history of nephrolithiasis but progression to chronic renal failure to exclude primary hyperoxaluria before isolated kidney transplantation is considered.

The demographic profile of urolithiasis in Iran: a nationwide epidemiologic study.

Abstract: The marked variations in urinary stone disease prevalence by age, gender, race, and geographic location may provide clues to their etiology and prevention. We investigated the demographic profile of urolithiasis across Iran to draw out implications for national healthcare policies. In a nationwide multi-center epidemiologic study from September 2006 to August 2007, a multi-stage stratified sampling was taken in 12 ecologic zones across Iran during four seasons. 6,089 imaging-proven cases were identified out of 117,956 referrals to the radiologic centers. The demographic characteristics of positive cases were determined by a detailed questionnaire. Target population characteristics were derived from the most recent formal national census (2006). Male-to-female ratio was 1.38 (male: 58%, female: 42%). Uneducated people ratio was significantly greater among stone formers. (Mean difference = 10.4%, 95% CI = 9–12%).Mean age at presentation was 41.5 years ± 16.3 and the peak incidence range was between 55 and 65 years. The most frequent co-existence diseases were hypertension (15.8%) and diabetes (11.4%). It ranged from 2.8 to 21.3 for diabetes and 6.1 to 30.4 for hypertension compared to 1 to 4.2% and 4 to 7.7, respectively, in the general population. Surprisingly, the number of current smokers among stone formers was significantly less than the general population. BMI failed to show a significant correlation. The putative risk factors for urinary stone disease were male gender, hypertension, diabetes mellitus, and lack of education. Preventive strategies based on indigenous demographic data may have a role in public healthcare policies.

Impact of Charlson’s comorbidity index on overall survival following tumor nephrectomy for renal cell carcinoma

Abstract: Objective To study the impact of Charlson’s comorbidity index on overall survival following radical and partial nephrectomy performed for renal cell carcinoma (RCC).

Acute kidney injury in the elderly population.

Abstract: The elderly population is more prone to acute kidney injury (AKI) than younger populations. Older patients have less renal reserve because of reduced glomerular filtration rates due to anatomic/functional changes, and concomitant diseases such as hypertension, diabetes, atherosclerosis, heart failure, ischemic renal disease, and obstructive uropathy. The risk of AKI may also increase as a result of aggressive diagnostic and therapeutic procedures, which include medical agents, radiology, and surgical intervention. AKI in the elderly has a multifactorial physiopathology due to different etiologies. Studies that have specifically compared prognosis of AKI in elderly versus young over the recent years suggest that age is a predictor of long-term outcome. In most cases, the treatment of AKI is similar for all age groups. The majority of critically ill patients with AKI will eventually need renal replacement therapy (RRT). The influence of RRT on renal outcome remains a subject of intense investigation and debate. Avoiding situations that could damage the kidney is an important strategy to prevent AKI development in the elderly, besides medical and interventional therapeutics.

New-onset diabetes after transplantation in tacrolimus-treated, living kidney transplantation: long-term impact and utility of the pre-transplant OGTT

Abstract: Background To evaluate the role of the oral glucose tolerance test (OGTT) before transplantation and to examine the risk factors for new-onset diabetes after transplantation (NODAT) during long-term follow-up of renal transplant recipients receiving FK-based therapy.

Antioxidant levels of common fruits, vegetables, and juices versus protective activity against in vitro ischemia/reperfusion

Abstract: It is well known that antioxidants present in various fruits, vegetables, and juices have the potential to protect the urinary bladder from free radical damage. What is not well understood, however, is how well antioxidant activities detected by chemical methods such as the CUPRAC assay for total antioxidant activity (TAA) predict the level of physiological protection available. It is hypothesized that the level of antioxidant reactivity found by the CUPRAC assay will positively correlate with increased protection in a model of in vitro ischemia/reperfusion. To test this hypothesis, the CUPRAC assay was utilized to determine the antioxidant reactivity of a series of fruits, vegetables, and juices, and the results were compared to the protective ability of selected juices in an established in vitro rabbit bladder model of ischemia/reperfusion. The results of the CUPRAC test showed that cranberry juice had the highest level of antioxidant reactivity, blueberry juice had an intermediate activity, and orange juice had the lowest. It was determined, however, that contrary to the hypothesis, the orange juice was significantly more potent in protecting the bladder against ischemia/reperfusion damage than either blueberry or cranberry juice. Thus, it is concluded that chemical tests for TAA do not necessarily correlate with their physiological activity.