Effects of Cinacalcet on Post-transplantation Hypercalcemia and Hyperparathyroidism in Adult Kidney Transplant Patients: A Single-Center Experience.

OBJECTIVE: Secondary hyperparathyroidism may manifest as hypercalcemia in the post-transplant period. The classical treatment method is parathyroidectomy and the alternative is oral cinacalcet, a calcimimetic agent therapy. We retrospectively investigated the effect of cinacalcet therapy on kidney and patient survival in these patients. MATERIALS AND METHODS: In our single-center, retrospective, observational study, files of 934 patients who underwent renal transplantation in our unit between 2008 and 2022 were reviewed. A total of 23 patients were started on cinacalcet for the treatment of hypercalcemia (calcium > 10.3 mg/dl) and parathyroid hormone (PTH) elevation (>65 pg/ml). Patients with calcium < 10.3 mg/dl and PTH > 700 pg/ml at any time in the follow-up after renal transplantation were included in the study. In addition, the demographic data of the patients, baseline creatine, calcium, phosphorus, and PTH levels at the time of hypercalcemia, parathyroid ultrasonography, parathyroid scintigraphy, creatinine, calcium, phosphorus, and PTH levels in the last controls, and survival status were evaluated. RESULTS:  The mean age of 23 patients included in the study was 52.7 ± 11 years (minimum: 32; maximum: 66). Of the patients, 16 (69.6%) were male, and 15 (65.2%) were transplanted from a living donor. Parathyroid scintigraphic revealed adenoma in three (13%) patients, hyperplasia in five patients (21.7%), and no involvement in 15 patients (65.2%). Cinacalcet treatment was initiated at a median of 33 months (interquartile range (IQR) = 13-96) after the kidney transplant operation. There was no graft loss in the patients during the follow-up period. Twenty-two patients (95.7%) were alive, and one patient died. The calcium level of the patients decreased from 11.3 ± 0.64 mg/dl to 9.98 ± 0.78 mg/dl (p = 0.001) after cinacalcet treatment. Phosphorus values increased from 2.7 ± 0.65 mg/dl to 3.10 ± 0.65 mg/dl (p = 0.004). On the other hand, there was no significant difference in PTH levels between the initial and final controls (285 (IQR = 150-573) vs. 260 pg/ml (IQR = 175-411), p = 0.650). Also, creatinine levels were similar (1.2 ± 0.38 vs. 1.24 ± 0.48 mg/dl, p = 0.43). Despite cinacalcet treatment, calcium levels did not decrease in eight patients. Complications such as renal dysfunction and pathological fracture did not develop in these patients. CONCLUSIONS: It seems that cinacalcet treatment is a suitable option for patients with hypercalcemia and/or hyperparathyroidism with low drug interactions and good biochemical control after renal transplantation.

Heme oxygenase-1 deficiency as an extremely rare cause of AA-type renal amyloidosis: Expanding the clinical features and review of the literature.

Heme oxygenase-1 (HMOX-1) is an enzyme that regulates heme degradation. Antiinflammatory, antioxidant, and cytoprotective effects of HMOX-1 were also described. It is encoded by the HMOX1 gene, and biallelic mutations cause HMOX-1 deficiency, which is a rare chronic multisystemic inflammatory disorder. This inflammatory status could lead to the development of secondary AA-type amyloidosis theoretically. Here, we report a 30-year-old male with AA-type renal amyloidosis due to a chronic inflammatory condition of unknown origin. Paternal consanguinity and dysmorphic features raised suspicion of a rare genetic disorder. Clinical exome sequencing (CES) confirmed the HMOX-1 deficiency diagnosis related to homozygous missense G139V mutation. To the best of our knowledge, our patient is the eleventh HMOX-1 deficiency case in the literature. Also, HMOX-1 deficiency-related systemic AA-type amyloidosis has not been reported before.

Post-COVID-19 outcomes of non-dialysis dependent chronic kidney disease patients: a national, multicenter, controlled study.

PURPOSE: Coronavirus disease 2019 (COVID-19) has a higher mortality in the presence of chronic kidney disease (CKD). However, there has not been much research in the literature concerning the outcomes of CKD patients in the post-COVID-19 period. We aimed to investigate the outcomes of CKD patients not receiving renal replacement therapy. METHODS: In this multicenter observational study, we included CKD patients with a GFR < 60 ml/min/1.73 m2 who survived after confirmed COVID-19. Patients with CKD whose kidney disease was due to diabetic nephropathy, polycystic kidney disease and glomerulonephritis were not included in this study. CKD patients with similar characteristics, who did not have COVID-19 were included as the control group. RESULTS: There were 173 patients in the COVID-19 group and 207 patients in the control group. Most patients (72.8%) were treated as inpatient in the COVID-19 group (intensive care unit hospitalization: 16.7%, acute kidney injury: 54.8%, needing dialysis: 7.9%). While there was no significant difference between the baseline creatinine values of the COVID-19 group and the control group (1.86 and 1.9, p = 0.978, respectively), on the 1st month, creatinine values were significantly higher in the COVID-19 group (2.09 and 1.8, respectively, p = 0.028). Respiratory system symptoms were more common in COVID-19 patients compared to the control group in the 1st month and 3rd month follow-ups (p < 0.001). Mortality at 3 months after the diagnosis of COVID-19 was significantly higher in the COVID-19 group than in the control group (respectively; 5.2% and 1.4%, p:0.037). Similarly, the rate of patients requiring dialysis for COVID-19 was significantly higher than the control group (respectively; 8.1% and 3.4%, p: 0.045). CONCLUSIONS: In CKD patients, COVID-19 was associated with increased mortality, as well as more deterioration in kidney function and higher need for dialysis in the post-COVID-19 period. These patients also had higher rate of ongoing respiratory symptoms after COVID-19.

Middle-term outcomes in renal transplant recipients with COVID-19: a national, multicenter, controlled study.

Background: In this study, we evaluated 3-month clinical outcomes of kidney transplant recipients (KTR) recovering from COVID-19 and compared them with a control group. Method: The primary endpoint was death in the third month. Secondary endpoints were ongoing respiratory symptoms, need for home oxygen therapy, rehospitalization for any reason, lower respiratory tract infection, urinary tract infection, biopsy-proven acute rejection, venous/arterial thromboembolic event, cytomegalovirus (CMV) infection/disease and BK viruria/viremia at 3 months. Results: A total of 944 KTR from 29 different centers were included in this study (523 patients in the COVID-19 group; 421 patients in the control group). The mean age was 46 ± 12 years (interquartile range 37-55) and 532 (56.4%) of them were male. Total number of deaths was 8 [7 (1.3%) in COVID-19 group, 1 (0.2%) in control group; P = 0.082]. The proportion of patients with ongoing respiratory symptoms [43 (8.2%) versus 4 (1.0%); P < 0.001] was statistically significantly higher in the COVID-19 group compared with the control group. There was no significant difference between the two groups in terms of other secondary endpoints. Conclusion: The prevalence of ongoing respiratory symptoms increased in the first 3 months post-COVID in KTRs who have recovered from COVID-19, but mortality was not significantly different.

CD133+ cells are associated with ADIPOCYTOKINES and endothelial dysfunction in hemodialysis patients.

BACKGROUND: Hemodialysis (HD) patients have increased risk of cardiovascular disease (CVD). Impaired stem cell health and adipocytokine metabolism may play important roles in the complex pathophysiological mechanisms of CVD in this patient population. We aimed to investigate the relationships between CD133+ cell counts, adipocytokines and parameters of endothelial dysfunction and atherosclerosis in HD patients. METHODS: In 58 chronic HD patients (male/female:28/30, mean age:58 ± 14 years), serum levels of interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), leptin, adiponectin and resistin were measured by ELISA. Left ventricular mass index (LVMI), carotid intima-media thickness (CIMT), flow-mediated dilatation (FMD) of the brachial artery were measured. CD133+ cells were counted by flow cytometry (BD FACSCalibur-BD Bioscience,CA). RESULTS: CD133+ cell counts were inversely associated with FMD (r = -0.39, p = 0.007) and positively correlated with serum resistin (r = 0.45, p < 0.001) and serum TNF-α (r = 0.31, p = 0.02). Serum leptin levels were higher in high CD133 group compared to low CD133 group [32.37(12.74-72.29) vs 15.50(5.38-37.12)ng/mL, p = 0.03]. Serum leptin levels were correlated with TNF-α(r = 0.35, p = 0.009). Serum adiponectin levels were negatively correlated with serum leptin (r = -0.28, p = 0.03). Serum resistin levels were associated with TNF-α (r = 0.54, p < 0.001) and leptin (r = 0.29, p = 0.03). Serum IL-6 levels were significantly associated with LVMI (r = 0.31, p = 0.03). Serum IL-6 levels were significantly higher in patients with carotid plaque compared to patients without plaque [12.75(9.91-28.68) vs 8.27(5.97-14.04) pg/mL, p = 0.02]. In multiple linear regression analysis to determine the factors predicting LogFMD; dialysis vintage, LVMI and LogCD133+ cell counts were included as independent variables(R = 0.57, adjusted R-square = 0.27, p = 0.001). CD133+ cell count and LVMI were found to significantly predict FMD (p = 0.03 and p = 0.04 respectively). CONCLUSION: CD133+ cells were associated with inflammation and endothelial dysfunction in HD patients. Serum leptin, resistin and TNF-α levels were positively related to CD133+ cell count. Impaired regulation of undifferentiated stem cells and adipocytokines might contribute to endothelial dysfunction in HD patients.

A Rare Clinical Entity: Staphylococcus-Related Glomerulonephritis.

Staphylococcus aureus is a rare cause of postinfectious glomerulonephritis, and Staphylococcus-related glomerulonephritis primarily occurs in middle-aged or elderly patients. Patients with Staphylococcus-related glomerulonephritis also present with hematuria, proteinuria of varying degrees, rising serum creatinine levels, and/or edema. The severity of renal insufficiency is proportional to the degree of proliferation and crescent formation. Here, we present a diabetic patient admitted with a history of 1 week of left elbow pain. Laboratory results revealed that erythrocyte sedimentation rate was 110 mm/hour, serum creatinine level was 1 mg/dL, C-reactive protein level was 150 mg/L, and magnetic resonance imaging showed signal changes in favor of osteomyelitis at the olecranon level, with diffuse edematous appearance in the elbow skin tissue and increased intra-articular effusion. After diagnosis of osteomyelitis, ampicillin/sulbactam and teicoplanin were administered. After day 7 of admission, the patient developed acute kidney injury requiring hemodialysis under antibiotic treatment. Kidney biopsy was performed to determine the underlying cause, which showed Staphylococcus-related glomerulonephritis. Recovery of renal functions was observed after antibiotic and supportive treatment.

Cardiovascular-renal changes after kidney donation: one-year follow-up study.

BACKGROUND: Long-term consequences of kidney donation are not well known. Most of the studies published were focused on renal risk. In this prospective study, we investigated the changes in cardiovascular function after kidney donation. METHODS: Thirty-eight living kidney donors were included. In addition to 24-hr ambulatory blood pressure monitoring, serum interleukin-6, vascular cell adhesion molecule (VCAM), and asymmetric dimethylarginine levels were measured. Endothelial function was examined by measuring ischemia-induced flow-mediated dilation (FMD) of the brachial artery. All studies were repeated at 3 months and 12 months after kidney donation. RESULTS: The mean serum interleukin-6 levels, both at 3 months and 12 months, were significantly increased as compared to the baseline (P = 0.007 and P < 0.001, respectively). The mean serum asymmetric dimethyl-arginine (P < 0.001) and VCAM levels (P < 0.001) at 12 months were significantly increased as compared to baseline. FMD values at 1 year (9.3% ± 7.1%) were significantly decreased as compared to 3 months (13.0% ± 6.0%, P = 0.001) and baseline (13.9% ± 6.3%, P = 0.002). In multivariate analysis, serum uric acid (P = 0.001), estimated glomerular filtration rate (P = 0.027), and VCAM (P = 0.014) levels were the independent predictors of FMD 12 months after kidney donation. CONCLUSION: Our findings suggest that kidney donation might increase the cardiovascular risk in kidney donors.

Elevated resistin levels are associated with inflammation in hemodialysis patients with failed renal allografts.

BACKGROUND: Resistin is an adipocytokine, associated with insulin resistance and inflammation. The aim of this study is to evaluate the levels of serum resistin levels and other markers of inflammation in hemodialysis (HD) patients with failed renal allografts. METHODS: Sixty-nine HD patients with failed renal allografts and 98 never transplanted (naive) HD patients and also 21 healthy controls were included in the study. Serum levels of various biochemical parameters as well as resistin, IL-6, TNF-α and hs-CRP as biochemical markers of inflammation, were measured. RESULTS: Serum resistin levels in patients with failed renal allografts (4.80 ± 2.06 ng/mL) were significantly higher than those of the naive HD patients (3.44 ± 1.48 ng/mL) and healthy controls (0.95 ± 0.38 ng/mL; p<0.001). Patients with failed transplants were also characterized by higher TNF-alpha levels (96.8 ± 131.3 pg/mL vs. 40.9 ± 25.4 pg/mL; p<0.001) and IL-6 levels (83.9 ± 150.9 pg/mL vs. 14.6 ± 14.4 pg/mL; p<0.001) as compared to naive HD patients. Serum hs-CRP levels in patients with failed renal allografts (9.33 ± 11.86 mg/L) were significantly higher than those of the naive HD patients (1.26 ± 1.71 mg/L) and healthy controls (2.12 ± 1.82 mg/L; p<0.001). Serum albumin levels in patients with failed transplants (3.84 ± 0.47 g/dL) were lower as compared to never transplanted HD patients (4.13 ± 0.33 g/dL) and healthy controls (4.53 ± 0.40 g/dL; p<0.001). There was a positive correlation between serum resistin and TNF-alpha levels (r = 0.486, p<0.001). CONCLUSIONS: Serum resistin levels are increased in HD patients with failed renal allografts very probably reflecting an allograft-induced chronic inflammatory state.

Influence of conversion from calcineurin inhibitors to everolimus on fibrosis, inflammation, tubular damage and vascular function in renal transplant patients.

BACKGROUND: Conversion from calcineurin inhibitor (CNI) to mTOR inhibitors may reduce and even halt the progression of chronic allograft dysfunction (CAD) which is the most important cause of renal allograft loss. We aimed to investigate the effects of conversion from CNI to everolimus on parameters of fibrosis, inflammation, glomerulotubular damage and vascular functions in renal transplant recipients. METHODS: Fifteen stable renal transplant recipients who were under CNI treatment (male/female 13/2, mean age 41 ± 10 years) were enrolled and switched to everolimus. Serum and urinary transforming growth factor-ß (TGF-ß), urinary neutrophil gelatinase-associated lipocalin (NGAL) and monocyte chemoattractant protein-1 (MCP-1) were measured as markers of fibrosis, tubular damage and inflammation. As parameters of vascular functions, pulse wave velocity (PWV), augmentation index (AIx), serum asymmetric dimethyl-arginine and fibroblast growth factor-23 (FGF-23) were measured. All these measurements were repeated at the 3rd month of conversion. RESULTS: Estimated GFR (52 ± 7-57 ± 11 ml/min/l.73 m(2), p = 0.02) (was increased after conversion to everolimus. However, serum uric acid levels were significantly decreased (6.21 ± 1.21-5.50 ± 1.39 mg/dL, p = 0.01). Serum TGF-ß levels (8727 ± 2897-1943 ± 365 pg/mL, p = 0.03) and urinary NGAL levels (26 ± 10-12 ± 2 ng/mg creatinine, p = 0.05) were significantly decreased. However, urinary MCP-1, FGF-23, PWV and AIx did not change. Urinary TGF-ß was associated with urinary NGAL (r = 0.62, p = 0.01), urinary MCP-1 (r = 0.68, p = 0.005) and proteinuria (r = 0.50, p = 0.05). CONCLUSION: Conversion from CNI to everolimus resulted in significant decreases of serum TGF-ß and urinary NGAL which may represent less fibrosis and tubular damage. Association of urinary TGF-ß with NGAL and MCP-1 suggests that tubular damage, fibrosis and inflammation may act together for progression of CAD.

FGF-23 associated with the progression of coronary artery calcification in hemodialysis patients.

BACKGROUND: Disordered mineral metabolism is implicated in the pathogenesis of vascular calcification in hemodialysis (HD) patients. Fibroblast growth factor 23 (FGF-23) is the main regulator of phosphate metabolism. In this prospective study, we aimed to investigate the association of serum FGF-23 with progression of coronary artery calcification in HD patients. METHODS: Seventy-four HD patients (36 male/38 female, mean age: 52 ± 14 years) were included. Serum FGF-23 levels were measured by ELISA. Coronary artery calcification score (CACS) was measured twice with one year interval. Patients were grouped as progressive (PG) (36 patients-48%) and non-progressive (NPG). RESULTS: Age, serum phosphorus, baseline and first year CACS were found to be significantly higher in the PG compared to NPG group. Serum FGF-23 levels were significantly higher in PG [155 (80-468) vs 147 (82-234), p = 0.04]. Patients were divided into two groups according to baseline CACS (low group, CACS ≤ 30; high group, CACS > 30). Serum FGF-23 levels were significantly correlated with the progression of CACS (ΔCACS) in the low baseline CACS group (r = 0.51, p = 0.006), but this association was not found in high baseline CACS group (r = 0.11, p = 0.44). In logistic regression analysis for predicting the PG patients; serum FGF-23, phosphorus levels and baseline CACS were retained as significant factors in the model. CONCLUSIONS: Serum FGF-23 was found to be related to progression of CACS independent of serum phosphorus levels. FGF-23 may play a major role in the progression of vascular calcification especially at the early stages of calcification process in HD patients.

Lower serum prohepcidin levels associated with lower iron and erythropoietin requirements in hemodialysis patients with chronic hepatitis C.

BACKGROUND: Patients with chronic HCV infection have increased liver iron. Recently identified protein hepcidin synthesized in the liver, is thought to be a key regulator for iron homeostasis and is induced by infection and inflammation. Lower erythropoietin and iron supplementation requirements were previously reported in HD patients with HCV infection. We investigated the association of prohepcidin with inflammation and iron parameters in HD patients with and without chronic HCV infection. METHODS: Sixty patients (27 male, 33 female, mean age 50±15 years) on chronic HD were included. Parameters related to iron metabolism (ferritin, serum iron and total iron binding capacity (TIBC)), inflammation (hs-CRP, TNF-α and IL-6) and prohepcidin levels were measured. The response to treatment (erythropoiesis-stimulating agent (ESA) resistance index) was assessed from the ratio of the weekly erythropoietin (rhuEPO) dose to hemoglobin (Hb) per unit weight. RESULTS: Serum prohepcidin levels of HCV positive patients (135±25 ng/mL) were significantly lower than HCV negative patients [148±18 ng/mL, (p=0.025)]. Serum IL-6 levels of HCV positive patients were also significantly lower than HCV negative patients (p=0.016). Serum prohepcidin levels were positively correlated with ferritin (r=0.405, p=0.001) and IL-6 (r=0.271, p=0.050) levels in HD patients. In the HCV positive group, serum prohepcidin levels significantly correlated with ferritin levels (r=0.514 p=0.004). In the HCV negative group, serum prohepcidin levels significantly correlated with serum IL-6 levels (r=0.418, p=0.027). In multiple regression analysis performed to predict prohepcidin in HCV positive patients, serum ferritin was found to be an independent variable (r=0.28, p=0.008). CONCLUSIONS: HCV positive HD patients have low levels of serum prohepcidin and IL-6 which might account for iron accumulation together with lower iron and rhuEPO requirements in these patients.

Evaluation of the medically complex living kidney donor.

Due to organ shortage and difficulties for availability of cadaveric donors, living donor transplantation is an important choice for having allograft. Live donor surgery is elective and easier to organize prior to starting dialysis thereby permitting preemptive transplantation as compared to cadaveric transplantation. Because of superior results with living kidney transplantation, efforts including the usage of "Medically complex living donors" are made to increase the availability of organs for donation. The term "Complex living donor" is probably preferred for all suboptimal donors where decision-making is a problem due to lack of sound medical data or consensus guidelines. Donors with advanced age, obesity, asymptomatic microhematuria, proteinuria, hypertension, renal stone disease, history of malignancy and with chronic viral infections consist of this complex living donors. This medical complex living donors requires careful evaluation for future renal risk. In this review we would like to present the major issues in the evaluation process of medically complex living kidney donor.

Osteoprotegerin/RANKL axis and progression of coronary artery calcification in hemodialysis patients.

BACKGROUND AND OBJECTIVES: Vascular calcification is associated with increased cardiovascular mortality in chronic hemodialysis patients. This prospective study investigated the relationship between serum osteoprotegerin, receptor activator of NF-κB ligand, inflammatory markers, and progression of coronary artery calcification score. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: Seventy-eight hemodialysis patients were enrolled. Serum IL-1ß, IL-6, TNF-α, osteoprotegerin, receptor activator of NF-κB, fetuin A, and bone alkaline phosphatase were measured by ELISA. Coronary artery calcification score was measured two times with 1-year intervals, and patients were classified as progressive or nonprogressive. RESULTS: Baseline and first-year serum osteoprotegerin levels were significantly higher in the progressive than nonprogressive group (17.39±9.67 versus 12.90±6.59 pmol/L, P=0.02; 35.17±18.35 versus 24±11.65 pmol/L, P=0.002, respectively). The ratio of serum osteoprotegerin to receptor activator of NF-κB ligand at 1 year was significantly higher in the progressive group (0.26 [0.15-0.46] versus 0.18 [0.12-0.28], P=0.004). Serum osteoprotegerin levels were significantly correlated with coronary artery calcification score at both baseline (r=0.36, P=0.001) and 1 year (r=0.36, P=0.001). Importantly, progression in coronary artery calcification score significantly correlated with change in serum osteoprotegerin levels (r=0.39, P=0.001). In addition, serum receptor activator of NF-κB ligand levels were significantly inversely correlated with coronary artery calcification scores at both baseline (r=-0.29, P=0.01) and 1 year (r=-0.29, P=0.001). In linear regression analysis for predicting coronary artery calcification score progression, only baseline coronary artery calcification score and change in osteoprotegerin were retained as significant factors in the model. CONCLUSIONS: Baseline coronary artery calcification score and serum osteoprotegerin levels were significantly associated with progression of coronary artery calcification score in hemodialysis patients.

Reduction of uric acid levels with allopurinol treatment improves endothelial function in patients with chronic kidney disease.

BACKGROUND: Endothelial dysfunction (ED) is a key event in the development of atherosclerotic cardiovascular disease (CVD) in patients with chronic kidney disease (CKD). Association of hyperuricemia with CVD has been previously reported in the nonuremic population. In this prospective study, we aimed to evaluate the effects of treatment of hyperuricemia with allopurinol on ED and changes in the serum reactive oxygen species in patients with CKD. METHODS: In this study, 19 (13 male) hyperuricemic (UA > 7 mg/dl) nondiabetic CKD patients without any comorbidity, aged < 60 years with creatinine clearance (CrCl) between 20 and 60 ml/min were evaluated. Endothelial functions were assessed by ischemia-induced forearm vasodilatation method (EDD). Oxidative stress was evaluated by measuring the serum oxidized LDL (ox-LDL), advanced oxidation protein products (AOPP) and nitrotyrosine (NT) levels. After measuring all these tests at baseline, allopurinol therapy was commenced for 8 weeks. After 8 weeks of allopurinol treatment, all measurements were repeated. Then, allopurinol treatment was ceased and same measurements were also repeated 8 weeks after ceasing of the treatment. RESULTS: Serum creatinine, total cholesterol, albumin, hs-CRP, CrCl and proteinuria levels of the patients were similar among three study periods. After allopurinol therapy, the mean serum UA and NT levels significantly reduced as compared to baseline. At the 8th week after cessation of allopurinol treatment, serum UA levels were significantly increased. After allopurinol therapy, EDD value increased from 5.42 ± 8.3% at baseline to 11.37 ± 9% (p < 0.001). At the 8th week after ceasing allopurinol treatment, EDD returned to baseline values (5.96 ± 8%, p < 0.001). CONCLUSION: Treatment of hyperuricemia with allopurinol improve ED in patients with CKD. However, mechanism responsible for this beneficial effect seems to be apart from antioxidant effects of allopurinol.

Comparison of markers of appetite and inflammation between hemodialysis patients with and without failed renal transplants.

OBJECTIVE: The survival of patients returning to hemodialysis (HD) following kidney transplant failure is unfavorable. However, the factors responsible for this poor outcome are largely unknown; chronic inflammation due to failed allograft and malnutrition may contribute to morbidity and mortality. We aim to compare the markers of appetite and malnutrition, and their relation with inflammation in HD patients with and without previous kidney transplantation. METHODS: Fifty-six patients with failed renal allografts at least 3 months on dialysis (31 men, 25 women; mean age, 46 ± 9 years) and 77 HD patients who never underwent a transplant (43 men, 34 women; mean age, 50 ± 15 years) were included in the study. The appetite and diet assessment tool (ADAT) was used to determine the self reported appetite of patients. Serum concentrations of ghrelin, leptin, insulin like growth factor 1 (IGF-1), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), and high-sensitivity C-reactive protein (hs-CRP) were measured. Associations among these variables were analyzed. RESULTS: There were no significant differences considering age, gender or duration of renal replacement therapy between the 2 groups. The scores from Appetite and Diet Assessment Tool were significantly higher in the failed-transplant group. Serum ghrelin levels were significantly higher and serum albumin levels were significantly lower in the failed-transplant group. Serum leptin levels were similar between 2 groups. In addition, hs-CRP, IL-6, and TNF-α levels, which were used as inflammatory parameters, were significantly higher in the failed-transplant group. CONCLUSIONS: Elevated serum ghrelin levels and inflammation may cause diminished appetite and malnutrition in patients with failed renal allografts, and higher levels of this hormone seem to be associated with inflammation caused by retained failed allografts.

Coronary artery calcification and coronary flow velocity in haemodialysis patients.

BACKGROUND: Decreased coronary flow reserve (CFR) is a marker of endothelial dysfunction, coronary artery calcification and inflammation, well-known cardiovascular risk factors in haemodialysis (HD) patients. In this study, we aimed to investigate the correlation of coronary artery calcification scores (CACS) with CFR in HD patients. METHODS: Sixty-four end-stage renal failure patients were enrolled in this study (38 males, 26 females). Thirty-nine healthy subjects (22 males, 17 females) were included in the control group. Biochemical parameters and acute-phase inflammation marker [high-sensitivity C-reactive protein (hs-CRP)] of patients were recorded before dialysis. The CACS were measured by electron beam computerized tomography method. CFR recordings were performed by trans-thoracic Doppler echocardiography. The relationship between CACS and CFR was evaluated. RESULTS: The mean CACS was 281 +/- 589 and 29 patients had CACS < 10. Patients with CACS > 10 had significantly lower CFR values compared to patients with CACS < 10 (1.56 +/- 0.38 vs 1.84 +/- 0.53, P = 0.024). However, there was no difference in hs-CRP values between the groups. CFR was negatively correlated with CACS (r = -0.276, P = 0.030). In multiple stepwise regression analysis, CACS was found to be an independent variable for predicting CFR (P = 0.048). During a follow-up of 18 months, 10 patients had experience of cardiovascular events. Patients with CACS > 10 had significantly higher event rate [34.5% (10/29) vs 0% (0/24)] compared to those with CACS < 10 (P = 0.001). Patients who developed cardiovascular events had significantly higher mean CACS and lower CFR values than the remaining group (P = 0.019 and P = 0.039). All of four patients who died during follow-up were in the CFR < 2 and CACS > 10 groups. CONCLUSIONS: CACS was associated with CFR in HD patients. However, we did not find any association of inflammation with CACS and CFR. This association between CFR and CACS might indicate two different (anatomical and functional) aspects of the common pathophysiology of the arterial system in HD patients.

Endothelial dysfunction in hemodialysis patients with failed renal transplants.

BACKGROUND: Endothelial dysfunction (ED) is a common precursor and denominator of cardiovascular events including development of atherosclerosis. In this cross-sectional study, we aimed to investigate ED, measured by coronary flow reserve (CFR) in hemodialysis (nHD) patients who were never transplanted and patients with failed renal transplants restarting hemodialysis (fTx-HD). METHODS: Forty nHD (24 males, mean age 39 ± 9 yr) and 43 fTx-HD patients (27 males, mean age 36 ± 9 yr) were included in the study. Clinical and biochemical parameters, including high-sensitive C-reactive protein (hs-CRP) levels were determined. Also, CFR measurements were used to evaluate ED. RESULTS: There were no significant differences regarding age, gender, smoking status, systolic and diastolic blood pressure levels, mean duration of HD treatment as well as Kt/V((urea)) values between the two groups. Time spent on dialysis in the nHD group and dialysis duration following failure of renal allograft in the fTx-HD group were similar. Serum creatinine, hemoglobin, hematocrit, calcium and phosphorus levels were similar between the two groups as well. When compared to nHD group, serum total cholesterol (139 ± 3 vs. 154 ± 3 mg/dL, p = 0.045), serum albumin (3.8 ± 0.3 g/dL vs. 4.1 ± 0.2 g/dL, p < 0.0001) and CFR (1.60 ± 0.2 vs. 1.75 ± 0.3, p = 0.028) levels were significantly lower, while serum hs-CRP levels (11 ± 15 mg/L vs. 3 ± 4 mg/L, p = 0.001) were significantly higher in the fTx-HD group. Serum hs-CRP negatively correlated (r = -0254, p = 0.021), while serum albumin positively correlated (r = 0402, p = 0.001) with CFR values. CONCLUSION: ED is more prominent in fTx-HD than the nHD patients. Inflammation, caused by failed renal allograft can be responsible for this abnormality.

Effect of pre-transplant dialysis modality on kidney transplantation outcome.

BACKGROUND: The effect of pre-transplant dialysis modality on early graft function is a matter of debate. Although some authors deny the existence of a significant influence, others suggest that peritoneal dialysis (PD) affects early graft function favorably, possibly by contributing to a more physiologic water balance. In the present study, we evaluated the influence of pre-transplant dialysis modality on early and late graft function. PATIENTS AND METHODS: We studied 745 patients who underwent a first renal transplantation during 1983-2006, comparing the records of 44 PD patients [26 male; mean age: 26 +/- 9 years (range: 8-56 years)] who received 36 living related and 8 cadaveric renal transplantations with those of a control group of 44 consecutive hemodialysis (HD) patients [26 male; mean age: 27 +/- 11 years (range: 7-49 years)] for the index cases. RESULTS: The groups showed no significant differences in donor type, human leukocyte antigen matching, immunosuppressive protocols, and duration of dialysis. Also, neither group differed significantly with regard to incidence of delayed graft function, acute tubular necrosis, wound infection, systemic viral and bacterial infections, or acute rejection in the early post-transplant period. In the late post-transplant period, incidences of chronic rejection, graft failure, and malignancies were also similar. During the follow-up period, 3 patients in the PD group experienced acute rejection, 2 developed cytomegalovirus (CMV) disease, and 5 developed various other infections. In the HD group, 4 patients experienced acute rejection, 1 developed CMV disease, and 8 experienced other infections. Five patients in the PD group and one in the HD group died with functioning grafts (p = 0.09). No differences were noted between the groups in the incidences of post-transplant cardiovascular complications, malignancies, and diabetes mellitus. In the PD group, 33 patients with functioning grafts are still being followed, 6 have returned to dialysis, and 5 have died. In the HD group, 38 patients with functioning grafts are still being followed, 5 have returned to dialysis, and 1 has died. CONCLUSIONS: As a pre-transplant dialysis modality, neither HD nor PD affects the outcome of renal transplantation.

Atherosclerosis and vascular calcification are independent predictors of left ventricular hypertrophy in chronic haemodialysis patients.

BACKGROUND: Accelerated atherosclerosis and vascular calcification are common in chronic haemodialysis (HD) patients. In this study, we aimed to investigate the relationship between left ventricular hypertrophy (LVH) in HD patients and atherosclerosis and vascular calcification measured by electron beam computed tomography (EBCT). METHODS: In a cohort of 118 HD patients (52 male, 66 female, mean age: 46+/-13 years), we measured biochemical parameters, including BUN, creatinine, albumin, haemoglobin, C-reactive protein and fibrinogen levels, and performed echocardiography, high-resolution B-mode carotid ultrasonography and EBCT in 85 of them. The degree of stenosis was measured at four different sites (communis, bulbus, interna and externa) in both carotid arteries. Carotid plaque scores were calculated by summing the degrees of stenosis measured at all locations. RESULTS: LVH was detected in 89 of the patients (75%). Plaque-positive patients had higher left ventricular mass index (LVMI) than plaque-negative patients (175+/-59 vs 143+/-46 g/m2, P = 0.003). LVMI was correlated with systolic blood pressure (r = 0.62, P<0.001), pulse pressure (r = 0.58, P<0.001), haemoglobin levels (r = - 0.25, P = 0.008), carotid plaque score (r = 0.32, P = 0.001) and coronary (CACS) and aortic wall calcification score (AWCS) (r = 0.34, P = 0.002 and r = 0.43, P<0.001, respectively). Multiple linear regression analysis (model r = 0.76) showed the independent factors related to LVMI to be systolic blood pressure, pulse pressure, CACS and presence of carotid plaques. CONCLUSION: Extra-coronary atherosclerosis and vascular calcification are associated with LVH in HD patients. Whether the treatment of atherosclerosis or vascular calcification may cause regression of or even prevent LVH in HD patients remains to be seen.

Carotid atherosclerosis is a predictor of coronary calcification in chronic haemodialysis patients.

BACKGROUND: Coronary artery calcification scores (CACS) calculated by electron beam computed tomography (EBCT) have been correlated with atherosclerotic burden in the non-uraemic population. However, the validity of this test in chronic haemodialysis patients (HD) is currently uncertain. In the present cross-sectional study, associations between carotid atherosclerosis and coronary calcification in HD patients are investigated. METHODS: We studied 79 chronic HD patients (39 male, 40 female; mean age, 45+/-12 years). The mean time on HD was 68+/-54 months (range, 6-187 months). In these patients, we measured serum calcium, phosphorus, total cholesterol, cholesterol subgroups and iPTH levels. EBCT, echocardiography, and high-resolution B-mode carotid Doppler ultrasonography were also performed. RESULTS: Plaque-positive HD patients had significantly higher CACS than plaque-negative patients (851+/-199 vs 428+/-185, mean+/-SE, P = 0.006). Coronary calcification scores were correlated with serum phosphorus (r = 0.37; P = 0.001). Only 8 of the 24 HD patients without coronary calcification had carotid plaques (33%), whereas 34 of the 53 patients with coronary calcification had carotid plaques (64%) (P = 0.015). Carotid plaque scores were correlated with CACS (r = 0.40; P = 0.001). A stepwise linear regression (model r = 0.72; P<0.001) revealed that CACS (log-transformed data of CACS) was associated with age (P<0.001), time on dialysis (P = 0.004), serum phosphorus level (P = 0.016) and carotid plaque scores (P = 0.037). CONCLUSIONS: Atherosclerosis is independently associated with coronary artery calcification and with hyperphosphataemia in chronic HD patients. CACS appeared to be predictive of both coronary atherosclerosis and carotid atherosclerosis.