Inverse Association of N-terminal Pro‒B-type Natriuretic Peptide Level With Metabolic Syndrome in Kidney Transplant Patients.

BACKGROUND: Low levels of natriuretic peptide may activate the renin-angiotensin-aldosterone system, which may contribute to the development of obesity. Therefore, in study we aim to evaluate the relationship between metabolic syndrome (MetS) and serum N-terminal pro‒B-type natriuretic peptide (NT-proBNP) concentration in kidney transplant recipients. METHODS: Fasting blood samples were obtained from 66 kidney transplant recipients. MetS and its components were defined using the diagnostic criteria of the International Diabetes Federation. RESULTS: A total of 20 patients (30.3%) had MetS. Hypertension, prevalence of diabetes, use of statin or fibrate, body weight, body mass index, waist circumference, body fat mass, and levels of systolic blood pressure, total cholesterol, triglyceride, blood urea nitrogen, insulin, and HOMA-IR were higher, whereas the levels of high-density lipoprotein cholesterol and NT-proBNP were lower in patients with MetS. Logarithmically transformed creatinine and log-HOMA-IR were associated with NT-proBNP levels in a multivariable linear regression analysis. Multivariate logistic regression analysis revealed that NT-proBNP was an independent predictor of MetS in kidney transplant recipients. CONCLUSION: Our study has revealed that fasting level of NT-proBNP was negatively associated with MetS and that serum creatinine and HOMA-IR were independent predictors of serum NT-proBNP level in kidney transplant recipients.

Inverse Association Between Serum Osteoprotegerin and Bone Mineral Density in Renal Transplant Recipients.

BACKGROUND: Osteoprotegerin (OPG) has pleiotropic effects on bone metabolism as well as endocrine function. Our aim was to evaluate the relationship between bone mineral density (BMD) and serum OPG concentration in renal transplant recipients. METHODS: Fasting blood samples were obtained from 69 renal transplant recipients. BMD was measured in lumbar vertebrae (L2-L4) by dual-energy X-ray absorptiometry. Eight patients (11.6%) had BMD values indicative of osteoporosis, 28 patients (40.6%) had BMD values indicative of osteopenia, and 33 patients had normal BMD values. Increased serum OPG levels (P < .001), decreased body mass index (BMI) (P = .033), and decreased body weight (P = .010) were significantly correlated with low lumbar T-score cut-off points between groups (normal, osteopenia, and osteoporosis). RESULTS: Women had significantly lower lumbar BMD values than men (P = .013). Menopause (P = .005), use of tacrolimus (P = .020), and use of cyclosporine (P = .046) were associated with lower lumbar BMD in renal transplant recipients. Univariate linear regression analysis revealed that lumbar BMD was positively correlated with height (P = .016), body weight (P = .001), and BMI (P = .015) and negatively correlated with age (P = .039) and log-OPG (P = .001). Multivariate linear regression analysis revealed that log-OPG (ß: -0.275, R(2) change = 0.154, P = .014), body weight (ß: 0.334, R(2) change = 0.073, P = .004), and age (ß: -0.285, R(2) change = 0.079, P = .008) were independent predictors of lumbar BMD values in renal transplant recipients. CONCLUSIONS: Serum OPG concentration correlated negatively with lumbar BMD values in renal transplant recipients.

Hyperleptinemia Is a Risk Factor for the Development of Central Arterial Stiffness in Kidney Transplant Patients.

BACKGROUND: Arterial stiffness could cause adverse outcomes in kidney transplant (KT) patients. Leptin has a role in influencing vascular smooth muscle that may contribute to atherosclerosis. The aim of this study was to evaluate the relationship between fasting serum leptin concentration and carotid-femoral pulse wave velocity (cfPWV) in KT patients. MATERIALS AND METHODS: Fasting blood samples were obtained from 55 KT patients and 65 subjects from the outpatient department were enrolled as the control group. The cfPWV values of >10 m/s were used to define as the high arterial stiffness group and <10 m/s as the low arterial stiffness group. The predictive ability of leptin for arterial stiffness of KT was assessed using receiver operating characteristic (ROC) curve and multivariate logistic regression analyses. RESULTS: Kidney transplant patients had lower hemoglobin, but higher blood urea nitrogen, creatinine, total cholesterol, diastolic blood pressure, intact parathyroid hormone levels, and leptin levels than controls. Although cfPWV levels were higher in KT patients, there is no difference of cfPWV levels between KT patients and control (P = .595). Fifteen KT patients (27.3%) were defined in the high arterial stiffness group, and serum leptin level was higher in the high arterial stiffness group compared with the low arterial stiffness group in KT patients (P < .001). Multivariate logistic regression analysis showed that leptin (odds ratio: 1.044, 95% confidence interval [CI]: 1.016-1.072, P = .002) was an independent predictor of arterial stiffness in KT patients. The sensitivity, specificity, positive predictive value, negative predictive value, and area under the ROC curve predicting arterial stiffness in KT patients were 73.33%, 87.5%, 68.7%, 89.7%, and 0.828 (95% CI: 0.703-0.917, P < .001), and the leptin cut-off value was 74.14 ng/mL. CONCLUSION: Serum fasting leptin level could predict the development of central arterial stiffness of KT patients.

N-terminal pro-B-type natriuretic peptide is inversely related to bone mineral density in renal transplant recipients.

INTRODUCTION: Bone mineral density (BMD) was significantly lower in heart failure patients. Our aim was to evaluate the relationship between BMD and fasting serum N-terminal pro-B-type natriuretic peptide (NT-proBNP) concentration in renal transplant recipients. METHODS: Fasting blood samples were obtained from 69 renal transplant recipients. BMD was measured by dual energy x-ray absorptiometry in lumbar vertebrae (L2-L4). Serum NT-proBNP levels were measured by electrochemiluminescence immunoassay. RESULTS: Among the renal transplant recipients, 8 patients (11.6%) had osteoporosis and 28 (40.6%) had osteopenia; 33 had a normal BMD. Increased serum NT-proBNP (P < .001) and decreased body mass index (P = .033) and body weight (P = .010) were significantly correlated with low lumbar T-score cutoff points between groups (normal, osteopenia, and osteoporosis). Women had lower lumbar BMD than did men (P = .013). Menopause in women (P = .005), use of tacrolimus (P = .020), and use of cyclosporine (P = .046) among renal transplant recipients were associated with lower lumbar BMD. Multivariate forward stepwise linear regression analysis of the significant variables revealed that log-transformed NT-proBNP (ß, -0.545; R(2) = 0.331; P < .001), and body weight (ß, 0.273, R(2) = 0.104; P = .005) were independent predictors of lumbar BMD values among the renal transplant recipients. CONCLUSIONS: Serum NT-proBNP concentrations correlate negatively with lumbar BMD values among renal transplant recipients and may be an alternative to energy x-ray absorptiometry for identifying at risk of osteoporosis in renal transplant recipients.

Serum leptin levels positively correlate with peripheral arterial stiffness in kidney transplantation patients.

BACKGROUND: Leptin is a protein predominantly produced by adipocytes that plays a pathophysiologic role in the pathogenesis of hypertension and cardiovascular diseases. The aim of this study was to evaluate the relationship between fasting serum leptin levels and peripheral arterial stiffness among kidney transplant (KT) patients. METHODS: Fasting blood samples were obtained from 74 KT patients. Brachial-ankle pulse wave velocity (baPWV) was measured in the right or left brachial artery to the ankle segments using an automatic pulse wave analyzer (VaSera VS-1000). Plasma leptin levels were measured using a commercial enzyme-linked immunosorbent assay kit. In this study, left or right baPWV values of less than 14.0 m/s were used to define the high arterial stiffness group. RESULTS: Forty KT patients (54.1%) were defined in high arterial stiffness group. Hypertension (P < .010), diabetes (P < .010), age (P = .010), KT duration (P = .013), triglyceride levels (P = .016), systolic blood pressure (P < .001), waist circumference (P = .031), and leptin level (P < .001) were higher, whereas serum high-density lipoprotein cholesterol level (P = .030) was lower in the high arterial stiffness group compared with the low arterial stiffness group. Multivariate logistic regression analysis showed that leptin (odds ratio, 1.033; 95% CI, 1.004-1.062; P = .023), KT duration (odds ratio, 1.023; 95% CI, 1.004-1.044; P = .020), and high-density lipoprotein cholesterol level (odds ratio, 0.925; 95% CI, 0.872-0.982; P = .010) were the independent predictors of peripheral arterial stiffness in KT patients. CONCLUSIONS: Serum fasting leptin level was positively associated with peripheral arterial stiffness among KT patients.

Fasting long-acting natriuretic peptide correlates inversely with metabolic syndrome in kidney transplant patients.

The metabolic syndrome (MetS) is a risk factor for posttransplant diabetes mellitus, chronic graft dysfunction, graft loss, occurrence of atherosclerotic events, and patient death among kidney transplantation patients. Long-acting natriuretic peptide (LANP) is among the peptide hormones in atrial natriuretic peptide prohormone. Low levels of natriuretic peptide may lead to reduced lipolysis and excessive weight gain in obese patients. This study was undertaken to evaluate the relationship between MetS and fasting serum LANP concentration among kidney transplanted patients. Fasting blood samples were obtained from 69 kidney recipients. The MetS and its components were defined using the diagnostic criteria of the International Diabetes Federation. Fasting LANP levels were measured using a commercial enzyme immunoassay kit. The prevalence rate of MetS was 20.3% (14/69). Fasting LANP level negatively correlated with MetS among these patients (P = .010). Using univariate linear regression analysis, serum LANP values were negatively correlated with hemoglobin (r = -0.252; P = .037), and positively correlated with blood urea nitrogen (r = 0.254; P = .035) and creatinine (r = 0.311; P = .009). Multivariate forward stepwise linear regression analysis of the significant variables revealed that creatinine (R(2) change = 0.097; P = .009) was an independent predictor of fasting serum LANP concentration among kidney transplanted patients. Serum LANP concentration correlates inversely with MetS; for these patients, creatinine is an independent predictor of the serum LANP value.

Hypoadiponectinemia correlates with metabolic syndrome in kidney transplantation patients.

Serum adiponectin values correlate inversely with the presence of metabolic syndrome (MS). This study was undertaken to evaluate the relationship between MS and fasting serum adiponectin concentrations in 55 kidney transplantation patients. MS and its components were defined using the diagnostic criteria of the International Diabetes Federation. Thirteen subjects (23.6%) with MS showed negative correlations with adiponectin levels (P = .035), which also negatively correlated with a number of MS criteria (P = .015). Univariate linear regression analysis showed, serum adiponectin values to negatively correlate with waist circumference (r = -0.367; P = .006), body mass index (r = -0.306; P = .023), and body fat mass (r = -0.373; P = .005). Multivariate forward stepwise linear regression analysis of the significant variables revealed that body fat mass (R(2) change = 0.139; P = .035) and waist circumference (R(2) change = 0.067; P = .041) were independent predictors of fasting serum adiponectin concentrations. Thus, serum adiponectin concentrations correlated inversely with MS. Body fat mass and waist circumference were independent predictors of serum adiponectin values in kidney transplant patients.

Fibrillary glomerulonephritis.

The occurrence of fibrillary glomerulonephritis is unusual in Taiwan, whereas it occurs in approximately 1% of renal biopsy specimens taken in the United States of American. This disease is characterized by extracellular randomly arranged non-branching Congo red-negative microfibrils within glomeruli. The microfibrils are less than 30 nm in diameter, and electron microscopy is essential for diagnosis. Differential diagnosis of the deposition of extracellular non-branching microfibrils within glomeruli is important because discrete diseases have different therapeutic and prognostic implications. The report will discuss two cases of biopsy-proved fibrillary glomerulonephritis who presented with proteinuria, hematuria, renal insufficiency, and hypertension. It is noteworthy that the renal function persistently went downhill, even though the physician treated the patients with corticosteroids, pulse treatment and immunosuppressive agents.