A novel mutation in a patient with familial renal hypouricemia type 2.

INTRODUCTION: Hypouricemia may be caused by disorders leading to decreased UA production, oxidation of UA to allantoin by drugs or increased renal tubular loss of filtered UA, renal hypouricemia (RHUC). RHUC may be resulted from familial or acquired disorders. Familial RHUC cases are classified according to the gene affected as type 1 (SLC22A12 gene) and type 2 (SLC2A9). Clinical importance of RHUC entity is mainly determined by emerging of acute kidney injury (AKI) after strenuous exercise and urolithiasis. CASE PRESENTATION: Here, we report a case of RHUC with increased fractional excretion of uric acid value of more than 100%, serum uric acid level of nearly zero, and exercise-induced AKI episodes clinically and a new unpublished homozygous (biallelic) mutation of c.1419+2T>G (IVS11+2T>G) in the SLC2A9 gene genetically for the first time to our knowledge. CONCLUSION: Clinicians should be aware of this rare entity defined as hereditary RHUC in order to provide long term renoprotection by advisements like simple precautions such as avoiding severe exercises.

A novel mutation in a patient with familial renal hypouricemia type 2.

INTRODUCTION: Hypouricemia may be caused by disorders leading to decreased UA production, oxidation of UA to allantoin by drugs or increased renal tubular loss of filtered UA, renal hypouricemia (RHUC). RHUC may be resulted from familial or acquired disorders. Familial RHUC cases are classified according to the gene affected as type 1 (SLC22A12 gene) and type 2 (SLC2A9). Clinical importance of RHUC entity is mainly determined by emerging of acute kidney injury (AKI) after strenuous exercise and urolithiasis. CASE PRESENTATION: Here, we report a case of RHUC with increased fractional excretion of uric acid value of more than 100%, serum uric acid level of nearly zero, and exercise-induced AKI episodes clinically and a new unpublished homozygous (biallelic) mutation of c.1419+2T>G (IVS11+2T>G) in the SLC2A9 gene genetically for the first time to our knowledge. CONCLUSION: Clinicians should be aware of this rare entity defined as hereditary RHUC in order to provide long term renoprotection by advisements like simple precautions such as avoiding severe exercises.

The Frequency and Outcome of Acute Kidney Injury in a Tertiary Hospital: Which Factors Affect Mortality?

Acute kidney injury (AKI) is a major cause of mortality and morbidity in hospitalized patients. Incidence and mortality rates vary from country to country, and according to different in-hospital monitoring units and definitions of AKI. The aim of this study was to determine factors affecting frequency of AKI and mortality in our hospital. We retrospectively evaluated data for 1550 patients diagnosed with AKI and 788 patients meeting the Kidney Disease: Improving Global Outcomes (KDIGO) guideline AKI criteria out of a total of 174 852 patients hospitalized in our institution between January 1, 2007 and December 31, 2012. Staging was performed based on KDIGO Clinical Practice for Acute Kidney Injury and RIFLE (Risk, Injury, Failure, Loss of kidney function and End-stage renal failure). Demographic and biochemical data were recorded and correlations with mortality were assessed. The frequency of AKI in our hospital was 0.9%, with an in-hospital mortality rate of 34.6%. At multivariate analysis, diastolic blood pressure (OR 0.89, 95% CI 0.87-0.92; P < 0.001), monitoring in the intensive care unit (OR 0.18, 95% CI 0.09-0.38; P < 0.001), urine output (OR 4.00, 95% CI 2.03-7.89; P < 0.001), duration of oliguria (OR 1.51, 95% CI 1.34-1.69; P < 0.001), length of hospitalization (OR 0.83, 95% CI 0.79-0.88; P < 0.001), dialysis requirement (OR 2.30, 95% CI 1.12-4.71; P < 0.05), APACHE II score (OR 1.16, 95% CI 1.09-1.24; P < 0.001), and albumin level (OR 0.32, 95% CI 0.21-0.50; P < 0.001) were identified as independent determinants affecting mortality. Frequency of AKI and associated mortality rates in our regional reference hospital were compatible with those in the literature. This study shows that KDIGO criteria are more sensitive in determining AKI. Mortality was not correlated with staging based on RIFLE or KDIGO. Nonetheless, our identification of urine output as one of the independent determinants of mortality suggests that this parameter should be used in assessing the correlation between staging and mortality.

Poststreptococcal glomerulonephritis in a patient with essential thrombocytosis.

In addition to being the main cause of glomerulonephritis in children, poststreptococcal glomerulonephritis (PSGN) has recently been shown in older patients, especially those with malignancy or diabetes mellitus. The pathogenesis of PSGN has been ascribed to activation of complement 3 (C3) of the alternative complement cascade which, along with immunoglobulin (Ig) G and IgM deposits, is observed in renal tissue. Our aim here is to discuss the probable causes of PSGN developing with isolated IgM deposition in a 52-year-old patient with essential thrombocytosis followed-up over the previous 3.5 years. These characteristics make our case the first to be reported in the literature.

Is there any interaction of resistin and adiponectin levels with protein-energy wasting among patients with chronic kidney disease.

The aim of this study was to evaluate the effects of adipocytokines including adiponectin, leptin, resistin, neuropeptide Y and ghrelin in chronic kidney disease (CKD) patients on appearance of protein-energy wasting (PEW). One hundred fifty patients with mean age of 45.4 ± 15.9 years, without active infections or chronic inflammatory conditions were recruited into the study. Study groups were control group (consisting of 30 healthy volunteers with normal kidney functions), hemodialysis group, predialysis group, peritoneal dialysis group and kidney transplant group. Fasting morning serum leptin, ghrelin, acylated ghrelin, neuropeptide Y, adiponectin, resistin levels of all of the groups were measured. Anthropometric and nutritional assessments of all patients were obtained. Diagnosis of PEW was made according to definition recommended by the International Society of Renal Nutrition and Metabolism. Presence of PEW in hemodialysis (23.3%) and peritoneal dialysis (26.7%) groups were significantly higher than those of predialysis (3.3%), and transplantation (0%) groups. Adiponectin and resistin levels in predialysis, peritoneal dialysis and hemodialysis patients were significantly higher than control group (p: 0.0001). This study had given significant positive correlations between presence of PEW and serum resistin (r: 0.267, p: 0.001), and serum adiponectin levels (r: 0.349, p: 0.0001). There were no relationship between presence of PEW and ghrelin, acylated-ghrelin, neuropeptide Y, and leptin levels of the groups. CKD patients except transplant patients had higher adiponectin and resistin levels than control group. PEW was found to be linearly correlated with resistin and adiponectin. High serum resistin and adiponectin levels might have a role in development of PEW among dialysis patients.

The role of adipocytokines on depressive symptoms of patients with chronic kidney disease.

OBJECTIVE: The aim of this study is to evaluate depression and anxiety scores among chronic kidney disease (CKD) patients and to search the changes of serum concentrations of adipokines with respect to emotional disturbances of CKD patients. PATIENTS AND METHODS: 150 patients recruited into this cross-sectional analytic study. Study groups were control, hemodialysis, predialysis, peritoneal dialysis and kidney transplantation groups. Fasting morning serum leptin, ghrelin, acylated ghrelin, neuropeptide Y, adiponectin, resistin levels of all of the groups were measured using ELISA (Sandwich) method. A screening interview based on the Structured Clinical Interview for DSM-IV and self-report scales (The Beck Depression [BDI] and The Beck Anxiety Inventory [BAI] and Brief Symptom Inventory [BSI] which is self report scales) were administered and conducted by a trained interviewer. RESULTS: BDI scores were significantly higher in hemodialysis and predialysis groups compared to control group (p = 0.009). Somatization sub scores of BSI were significantly higher in hemodialysis and peritoneal dialysis groups compared to control group (p = 0.041). Also positive symptom distress index scores of BSI were significantly higher in hemodialysis and transplantation groups compared to control group (p = 0.047). BDI score were significantly negatively correlated with duration of education (r = -0.165, p = 0.045), positively correlated with presence of protein energy wasting (r = 0.198, p = 0.016), and resistin levels (r = 0.233, p = 0.004). CONCLUSION: CKD patients had higher BDI, BSI-somatization, BSI-positive symptom distress index scores compared to control group. High serum resistin levels, presence of protein energy wasting might have a role in development of depressive disorders of patients with chronic kidney disease.

A case of recurrent episodes of acute renal allograft failure caused by renal pedicle tortion.

BACKGROUND: Acute allograft failure which occur intermittently after renal transplantation caused by graft tortion is a very rare entity. We here report highly unusual case of recurrent episodes of acute allograft dysfunction two years after kidney transplantation secondary to ischemic tubular necrosis caused by tortion of renal pedicle due to rotation of the allograft with body movements. CASE PRESENTATION: A 55 year-old male patient with living unrelated kidney transplantation for chronic renal failure caused by autosomal dominant polycystic kidney disease had presented recurrent acute deteriorations in renal functions. All laboratory values were within normal limits except elevated serum creatinine levels, acute tubular necrosis in graft biopsy, and detection of pelvic dilatation in renal ultrasonography from time to time. Changes in axis of graft in nuclear medicine scans taken at different times during the same study made us bring to mind the diagnosis of renal pedicle tortion. Renal blood flow measurements with Doppler ultrasonography in different body positions helped to reach the final diagnosis of mobile kidney right on time. The patient is now well after prompt surgical treatment with nephropexy. DISCUSSION: Unfortunately, tortion of allograft once occurred is associated with very high rate of graft loss due to arterial compromise and infarction and it is very difficult to diagnose without high level of suspicion. We discuss the causes of renal allograft tortion and the measures to prevent its occurrence and the methods to diagnose.

Do hemodialysis adequacy data reflect reality?

Hemodialysis (HD) adequacy requires monitoring in line with standards and at appropriate intervals. However, the use of inappropriate or incorrectly applied techniques in the determination of HD adequacy can lead to highly unfortunate results. This study was intended to identify the path to a solution by determining how far HD adequacy in HD centers in our region reflects reality. Three hundred and thirty HD patients from eight centers were included. On the first visit, predialysis and postdialysis blood collection with the centers' own methods being used were observed and errors were recorded. Kt/V1 was calculated from pre- and postdialysis blood specimens taken by the units themselves. On the second visit, one session later, pre- and postdialysis blood samples were collected in line with guidelines by ourselves, the authors, and Kt/V2 was calculated from these samples. The eight units' total Kt/V2 value was significantly lower compared with Kt/V1 (<0.0001). The level of patients in all centers with Kt/V1 <1.2 was 13.5%, and that of patients with Kt/V2 <1.2 was 22.1%. No center, apart from one unit, managed to complete the collection of blood specimens as recommended by the guidelines. With one exception, blood collection for HD adequacy was not performed using proper technique in any center. This simple but easily overlooked situation, HD being regarded as adequate though in fact it is not, may lead to patients not being treated effectively and accurately and to a rise in mortality and morbidity in the long term.

Thrombin activatable fibrinolysis inhibitor (TAFI) levels in hypertensive patients and a comparison of the effects of amlodipine and ramipril on TAFI levels.

Hypertension is associated with fibrinolysis abnormality. Thrombin-activatable fibrinolysis inhibitor (TAFI) is a novel molecule-linking coagulation and fibrinolysis. The aim of this study was to investigate the levels of TAFI in primary hypertensive patients and to compare the effects of amlodipine and ramipril on TAFI levels. The study was performed with 58 hypertensive subjects and 27 healthy volunteers. Biochemical and hematological parameters and TAFI levels were measured at baseline and after 1-month follow-up. TAFI concentrations increased in hypertensive patients compared with the controls (P = .030). Additionally, TAFI levels decreased with blood pressure control at 1-month follow-up (P = .026). There was no significant difference between TAFI levels in the amlodipine and ramipril groups at baseline. However, after 1-month follow-up, TAFI levels were decreased in the amlodipine group (P = .037) but not in the ramipril group. Our study is the first in the literature to determine increased TAFI levels in primary hypertension patients. In addition, we determined a decrease in TAFI levels in the amlodipine group after 1 month, but none in the ramipril group.

A comparison of the effects of fixed dose vs. single-agent combinations on 24-h blood pressure variability.

In addition to high blood pressure (BP), BP variability has recently also been shown to increase cardiovascular events. The purpose of this study was to compare the effect of a fixed-dose combinations (FDCs) of valsartan/amlodipine and a valsartan- and amlodipine-free drug combination on 24-h BPV. A total of 85 patients aged 18 or older and with no exclusion criteria were enrolled; of the 85 patients, 43 used the FDCs valsartan/amlodipine (160/10 mg) and 42 used a free drug combination of valsartan 160 mg and amlodipine 10 mg. Twenty-four hour ambulatory BP monitoring (ABPM) was performed after office BP measurements. Mean hourly BP, all-day BP reduction, trough/peak (T/P) ratio and Smoothness Index (SI) were calculated from the 24-h ABPM data. These were calculated separately for all-day, daytime, nighttime and early morning periods. The hourly mean diastolic BP (DBP) at 0800 hours in the FDCs group was significantly higher compared with the free drug combination group in the 24-h BP chronogram (P=0.041). Decreases in the all-day, daytime, nighttime and early morning systolic BP (SBP) and DBP in patients using a free drug combination were significantly greater compared with the FDC group. The SI and T/P ratio of the all-day, daytime and nighttime systolic and diastolic were also significantly higher compared with the FDC group. In addition, nighttime DBP reduction and the SI of DBP were lower in the diabetic patients. A free drug combination of amlodipine and valsartan provides more effective and smooth SBP and DSP control compared with FDCs.

Protective effect of the grape seed proanthocyanidin extract in a rat model of contrast-induced nephropathy.

AIM: Contrast-induced nephropathy (CIN) is a common cause of hospital-acquired acute renal failure. Although it is so common, there has been no approved therapy yet. We aimed to investigate the effect of grape seed proanthocyanidin extract (GSPE) on preventing CIN. MATERIALS AND METHODS: 24 rats were divided into four groups as control group, GSPE group, contrast medium (CM) group, and CM+GSPE group. The experiment was discontinued on the ninth day. Blood samples were obtained for the measurement of renal function parameters. Renal tissues of the rats were removed for the analysis of oxidative system parameters. In addition to renal histopathology, transferase-mediated deoxyuridine triphosphate nick end labeling (TUNEL) was performed to determine apoptosis. RESULTS: There was a significant increase in BUN, creatinine, malondialdehyde (MDA) levels, apoptotic index (AI) and histopathological alteration in the CM group as compared to the control group. Furthermore, BUN, creatinine, MDA, total oxidant system and oxidative stress index levels, AI as well as renal histopathological alteration were significantly decreased in the CM+GSPE group. CONCLUSION: For the first time in the literature, we showed that GSPE provided biochemical and histopathological improvement in CIN. Our findings revealed that this improvement was associated with the decrease in oxidative damage and apoptosis.