The influence of CTLA-4 single nucleotide polymorphisms on acute kidney allograft rejection in Turkish patients.

Cytotoxic T-lymphocyte antigen-4 (CTLA-4) is a cell surface protein, which down-regulates the immune response at CTLA-4/CD28/B7 pathway. We aimed to investigate the influence of the -318 C/T, +49 A/G, -1661 A/G and CT60A/G, and CTLA-4 gene polymorphisms on acute rejection of kidney allograft in Turkish patients. The study design was a case-control study that consists of three groups: Group 1 (n = 34) represented the kidney transplant (Ktx) recipients who experienced acute rejection, Group 2 (n = 47) was randomly assigned Ktx recipients without acute rejection, and Group 3 (n = 50) consisting of healthy volunteers to evaluate the normal genomic distribution. The polymerase chain reaction-restriction fragment length polymorphism technique was used to determine the polymorphisms. Genotype and allele frequencies among three groups denoted similar distributions for +49 A/G, -1661 A/G, and CT60A/G. Conversely, -318 C/T genotype was three times more frequent in the acute rejection group than in the non-rejection group (OR = 3.45; 95%CI = 1.18-10.1, p = 0.015) and two times more frequent than the healthy control group (OR = 2.45; 95% CI = 0.98 - 6.11, p = 0.047). Additionally, having a T allele at -318 position was significantly associated with acute rejection (0.147 vs. 0.043, OR = 3.45; 95% CI = 1.13-10.56, p = 0.02). 318C/T gene polymorphism and T allelic variant were found to be associated with increased acute rejection risk in Turkish kidney allograft recipients.

Is Klotho F352V Polymorphism the Missing Piece of the Bone Loss Puzzle in Renal Transplant Recipients?

BACKGROUND: Bone disorders are next to cardiovascular problems in frequency in renal transplant (RT) recipients. Reduction in 1,25-dihydroxycholecalciferol (1,25D) levels is among the reasons causing bone loss in these patients. Klotho (KL) serves as a co-receptor for fibroblast growth factor 23 (FGF23), and functions in vitamin D metabolism. KL polymorphisms have been identified in several studies, and phenylalanine to valine substitution at amino acid position 352 seemed to be important to KL function. We investigated KL F352V polymorphism and its relation with 1,25D levels in RT recipients. METHODS: The study included 25 RT recipients (8 female, 17 male) and 26 (14 female, 12 male) healthy control subjects who were wild (FF) phenotypes in terms of KL F352V polymorphism. RT recipients with (FV, n = 11) and without (FF, n = 14) a heterozygote polymorphism were determined with high resolution DNA melting analysis of KL F352V polymorphism. Serum 1,25D levels were measured using the RIA method. RESULTS: RT recipients with FV phenotype had significantly lower 1,25D levels (17.58 ± 18.38 pg/ml) compared to recipients with FF phenotype (44.91 ± 24.68 pg/ml) and control subjects (28.24 ± 12.13 pg/ml). 1,25D levels in RT recipients with FF phenotype were significantly higher than control subjects. CONCLUSIONS: KL F352V polymorphism may increase the expression of FGF23 co-receptor, KL protein and thus may decrease renal expression of 1α-hydroxylase, and/or stimulate 24-hydroxylase in RT recipients. The resultant decrease 1,25D levels may participate in bone loss in these patients.

Mutations in RAB27A cause Griscelli syndrome associated with haemophagocytic syndrome.

Griscelli syndrome (GS, MIM 214450), a rare, autosomal recessive disorder, results in pigmentary dilution of the skin and the hair, the presence of large clumps of pigment in hair shafts and an accumulation of melanosomes in melanocytes. Most patients also develop an uncontrolled T-lymphocyte and macrophage activation syndrome (known as haemophagocytic syndrome, HS), leading to death in the absence of bone-marrow transplantation. In contrast, early in life some GS patients show a severe neurological impairment without apparent immune abnormalities. We previously mapped the GS locus to chromosome 15q21 and found a mutation in a gene (MYO5A) encoding a molecular motor in two patients. Further linkage analysis suggested a second gene associated with GS was in the same chromosomal region. Homozygosity mapping in additional families narrowed the candidate region to a 3.1-cM interval between D15S1003 and D15S962. We detected mutations in RAB27A, which lies within this interval, in 16 patients with GS. Unlike MYO5A, the GTP-binding protein RAB27A appears to be involved in the control of the immune system, as all patients with RAB27A mutations, but none with the MYO5A mutation, developed HS. In addition, RAB27A-deficient T cells exhibited reduced cytotoxicity and cytolytic granule exocytosis, whereas MYO5A-defective T cells did not. RAB27A appears to be a key effector of cytotoxic granule exocytosis, a pathway essential for immune homeostasis.

Lymphocyte and monocyte vitamin D receptor expression during paricalcitol or calcitriol treatments in patients with stage 5 chronic kidney disease.

PURPOSE: In this study, we aimed to investigate the effect of paricalcitol and calcitriol usage on vitamin D receptor (VDR) contents of CD8+ , CD4+ lymphocytes and monocytes in stage 5d chronic kidney disease (CKD) patients. METHODS: Thirty-six hemodialysis patients older than 18 years of age and 19 healthy controls (group HC) without any known acute or chronic diseases were included in the study. The group of patients undergoing scheduled hemodialysis comprised three subgroups: group CL: patients on calcitriol (n: 10), group PC: patients on paricalcitol (n: 13), and group NT: patients not taking any vitamin D or VDR activating medications (n: 13). CD8+/VDR, CD4+/VDR and MONO/VDR values were representing the ratio of VDR representing cells among related cell group. On the other hand, values of CD8+/MFI, CD4+/MFI and MONO/MFI have shown the total amount of cellular VDR content per cell which has been given as of mean fluorescence intensity in the flow cytometric process. Main CKD mineral bone disorder parameters such as a hemogram, serum BUN, creatinine, albumin, Ca, iP, iPTH, 25(OH)D3 levels were also measured. RESULTS: Average VDR contents in CD8+, CD4+ and monocytes were not different among three patient groups on hemodialysis. But in all hemodialysis subgroups, CD8+/VDR, CD4+/VDR, MONO/VDR, CD8+/MFI, CD4+/MFI and MONO/MFI levels were found to be higher compared with the healthy control subjects (p < 0.001). Among hemodialysis groups, no significant CD8+/VDR, CD4+/VDR, and MONO/VDR content differences were found with regard to the type of VDR activator agent used. There was no difference in serum levels of 25(OH)D3 and CRP among groups participating in the study. CONCLUSION: There was no difference between CD8+/VDR, CD4+/VDR, and MONO/VDR levels in hemodialysis patients using calcitriol or paricalcitol, suggesting that both treatment agents may have a similar effect on VDR contents in lymphocytes and monocytes in that patient population. But in all hemodialysis subgroups, CD8+/VDR, CD4+/VDR, and MONO/VDR levels were found to be higher compared with the healthy control subjects, suggesting an overexpression of VDR through a non CRP and/or 25(OH)D3 dependent mechanism.

Advanced oxidative protein products are independently associated with endothelial function in peritoneal dialysis patients.

AIM: Oxidative stress (OS) and asymmetric dimethylarginine (ADMA) are accepted as non-classical cardiovascular risk factors in end-stage renal disease patients. To clarify the role of these factors in the atherosclerotic process, we investigated if OS and ADMA are associated with endothelial function (EF) in peritoneal dialysis (PD) patients. METHODS: Fifty-two non-diabetic PD patients without known atherosclerotic disease as well as 30 age- and sex-matched healthy individuals were included. We measured serum thiobarbituric acid-reactive substances (TBARS), malondialdehyde (MDA), advanced glycation end-product (AGE), pentosidine, advanced oxidation protein products (AOPP), ADMA and EF as described by Celermejer et al. in all subjects. RESULTS: TBARS, MDA, AOPP, AGE, pentosidine and ADMA levels were significantly higher in PD patients than in controls (P < 0.001). Flow-mediated dilatation (FMD)% and nitrate mediated dilatation (NMD)% in PD patients were lower than in the control group (7.7 +/- 4.0% vs 11.70 +/- 5.50%, P < 0.01 and 17.6 +/- 8.3% vs 26.4 +/- 4.6%, P < 0.01). Additionally, it was found that AOPP are independently correlated with FMD% and NMD% in PD patients (beta = -463, P < 0.01 and beta = -420, P < 0.05). CONCLUSION: This study shows that PD patients without known atherosclerotic disease can also be characterized by endothelial dysfunction and AOPP levels independently predict endothelial function level in PD patients.

Improving technique survival in peritoneal dialysis: what is modifiable?

The continuous quality improvement approach in peritoneal dialysis practice necessitates definition of the factors and the procedures that may possibly be contributing to the final success of peritoneal dialysis. The philosophy of continuous quality improvement uses the Plan, Do, Check, Act (PDCA) cycle. To improve the procedures used during peritoneal dialysis, the first step is to create a plan, then to carry out the plan, to check it, and after the collection of satisfactory information, to execute the chosen improvement action. Several studies have identified the most frequent causes of transfer from PD to HD as infection, catheter problems, inadequate dialysis, and psychosocial factors, among others. According to training guidelines from the International Society for Peritoneal Dialysis, seven points are of major importance to decrease infection risks: exit-site care, catheter placement, antibiotic prophylaxis for procedures, prevention of bowel-source peritonitis, prevention of fungal peritonitis, and connection methods. On the other hand, other factors such as hypoalbuminemia, depression, and obesity should also be taken into consideration for better technique survival in peritoneal dialysis patients.

Treatment of secondary hyperparathyroidism with paricalcitol in patients with end-stage renal disease undergoing hemodialysis in Turkey: an observational study.

OBJECTIVE: To evaluate monthly percentage changes of intact parathyroid hormone (iPTH) and other major bone marker levels in patients with secondary hyperparathyroidism (SHPT) undergoing hemodialysis (HD) and receiving paricalcitol. METHODS: A total of 493 (F/M 244/249) adult patients with SHPT who were undergoing HD in 22 HD units and receiving paricalcitol treatment, with iPTH > 300 mg/mL, adjusted serum levels of calcium (Ca) < 10.2 mg/dL, and serum levels of inorganic phosphorus (iP) < 6 mg/dL were included in this multi-center, national, prospective, observational study. Data regarding efficacy, safety, and adverse events of paricalcitol treatment were collected during a 12-month follow-up period through monthly visits along with serum iPTH, Ca, iP, alkaline phosphatase (ALP) and other required biochemistry tests as necessary. Mortality data until 6 months after the end of the study were also investigated. RESULTS: The mean age was 58.3 ± 15.8 years and the mean duration of HD was 6.2 ± 5.5 years, respectively. As of 12th month, mean iPTH values decreased from 646 ± 424 pg/mL to 473 ± 387 pg/mL (p < 0.001); no statistically significant changes were observed in Ca levels (p > 0.05). Serum ALP levels also significantly decreased (p = 0.001) and serum phosphorus levels significantly increased (p < 0.001) during the study observation period. Reasons for early terminations were being lost to follow-up (n = 119, 24.1%), hyperphosphatemia (iP > 6 mg/dL, n = 108, 21.9%), low iPTH levels (iPTH < 150 mg/dL, n = 97, 19.7%), and withdrawal of consent (n = 41, 8.3%). In total 32 patients (6.5%) were prematurely terminated the study with hypercalcemia (Ca > 10.2 mg/dL). 46.9% of those hypercalcemic patients had other anomalies with iP and iPTH levels along with hypercalcemia. CONCLUSION: Paricalcitol treatment, resulted in successful iPTH control. In approximately 6.5% of the patients paricalcitol treatment was discontinued since Ca levels reached > 10.2 mg/dL in those patients. No unfavorable effects on serum phosphorus and Ca-phosphorus (Ca × P) product were observed.

Oxidative stress and asymmetric dimethylarginine is independently associated with carotid intima media thickness in peritoneal dialysis patients.

BACKGROUND: Oxidative stress (OS) and asymmetric dimethylarginine (ADMA) are accepted as nonclassical cardiovascular risk factors in end-stage renal disease patients. To clarify the role of these factors in the atherosclerotic process, we investigated if OS and ADMA are associated with common carotid artery intima media thickness (CIMT) in peritoneal dialysis (PD) patients. METHODS: Thirty PD patients without known atherosclerotic disease and classical cardiovascular risk factors as well as age- and gender-matched 30 healthy individuals were included. We measured serum thiobarbituric acid-reactive substances (TBARS), malondialdehyde (MDA), advanced glycation end product (AGE), pentosidine, advanced oxidation protein products (AOPP), ADMA and CIMT in each subjects. RESULTS: TBARS, MDA, AOPP, AGE, pentosidine and ADMA levels were significantly higher in PD patients than in controls (p < 0.001). CIMT in patients was higher than in the control group (0.83 +/- 0.09 vs. 0.77 +/- 0.06 mm; p < 0.01). CIMT was independently correlated with TBARS (beta = 0.33, p < 0.01), MDA (beta = 0.27, p < 0.01), AOPP (beta = 0.22, p < 0.02), AGE (beta = 0.45, p < 0.01), pentosidine (beta = 0.56, p < 0.01) and ADMA (beta = 0.54, p < 0.01). CONCLUSIONS: OS markers and serum ADMA levels independently predict the CIMT level in PD patients.

Phosphorus control in peritoneal dialysis patients.

Hyperphosphatemia is independently associated with an increased risk of death among dialysis patients. In this study, we have assessed the status of phosphate control and its clinical and laboratory associations in a large international group of patients on chronic peritoneal dialysis (PD) treatment. This cross-sectional multicenter study was carried out in 24 centers in three different countries (Canada, Greece, and Turkey) among 530 PD patients (235 women, 295 men) with a mean+/-s.d. age of 55+/-16 years and mean duration of PD of 33+/-25 months. Serum calcium (Ca(2+)), ionized Ca(2+), phosphate, intact parathyroid hormone (iPTH), 25-hydroxy vitamin D(3), 1,25-dihydroxy vitamin D(3), total alkaline phosphatase, and bone alkaline phosphatase concentrations were investigated, along with adequacy parameters such as Kt/V, weekly creatinine clearance, and daily urine output. Mean Kt/V was 2.3+/-0.65, weekly creatinine clearance 78.5+/-76.6 l, and daily urine output 550+/-603 ml day(-1). Fifty-five percent of patients had a urine volume of <400 ml day(-1). Mean serum phosphorus level was 4.9+/-1.3 mg per 100 ml, serum Ca(2+) 9.4+/-1.07 mg per 100 ml, iPTH 267+/-356 pg ml(-1), ionized Ca(2+) 1.08+/-0.32 mg per 100 ml, calcium phosphorus (Ca x P) product 39+/-19 mg(2)dl(-2), 25(OH)D(3) 8.3+/-9.3 ng ml(-1), 1,25(OH)(2)D(3) 9.7+/-6.7 pg ml(-1), total alkaline phosphatase 170+/-178 U l(-1), and bone alkaline phosphatase 71+/-108 U l(-1). While 14% of patients were hypophosphatemic, with a serum phosphorus level lower than 3.5 mg per 100 ml, most patients (307 patients, 58%) had a serum phosphate level between 3.5 and 5.5 mg per 100 ml. Serum phosphorus level was 5.5 mg per 100 ml or greater in 28% (149) of patients. Serum Ca(2+) level was > or =9.5 mg per 100 ml in 250 patients (49%), between 8.5 and 9.5 mg per 100 ml in 214 patients (40%), and lower than 8.5 mg per 100 ml in 66 patients (12%). Ca x P product was >55 mg(2)dl(-2) in 136 patients (26%) and lower than 55 mg(2)dl(-2) in 394 patients (74%). Serum phosphorus levels were positively correlated with serum albumin (P<0.027) and iPTH (P=0.001), and negatively correlated with age (P<0.033). Serum phosphorus was also statistically different (P = 0.013) in the older age group (>65 years) compared to younger patients; mean levels were 5.1+/-1.4 and 4.5+/-1.1 mg per 100 ml, respectively, in the two groups. In our study, among 530 PD patients, accepted uremic-normal limits of serum phosphorus control was achieved in 58%, Ca x P in 73%, serum Ca(2+) in 53%, and iPTH levels in 24% of subjects. Our results show that chronic PD, when combined with dietary measures and use of phosphate binders, is associated with satisfactory serum phosphorus control in the majority of patients.

Mutations in Igalpha (CD79a) result in a complete block in B-cell development.

Mutations in Btk, mu heavy chain, or the surrogate light chain account for 85-90% of patients with early onset hypogammaglobulinemia and absent B cells. The nature of the defect in the remaining patients is unknown. We screened 25 such patients for mutations in genes encoding components of the pre-B-cell receptor (pre-BCR) complex. A 2-year-old girl was found to have a homozygous splice defect in Igalpha, a transmembrane protein that forms part of the Igalpha/Igbeta signal-transduction module of the pre-BCR. Studies in mice suggest that the Igbeta component of the pre-BCR influences V-DJ rearrangement before cell-surface expression of mu heavy chain. To determine whether Igalpha plays a similar role, we compared B-cell development in an Igalpha-deficient patient with that seen in a mu heavy chain-deficient patient. By immunofluorescence, both patients had a complete block in B-cell development at the pro-B to pre-B transition; both patients also had an equivalent number and diversity of rearranged V-DJ sequences. These results indicate that mutations in Igalpha can be a cause of agammaglobulinemia. Furthermore, they suggest that Igalpha does not play a critical role in B-cell development until it is expressed, along with mu heavy chain, as part of the pre-BCR.

Osteoporosis in the elderly with chronic kidney disease.

Considering the aging dialysis population of today, increasing our knowledge about the nature, diagnosis and the treatment of bone mineral density (BMD) problems in end-stage renal disease (ESRD) patients deserves more attention. Osteoporosis is basicly defined as a decrease in bone mass. Large epidemiological studies in general population have identified several risk factors for osteoporosis including advancing age, female gender, white race, decreased calcium intake, gastric acid suppression therapy, sedentary lifestyle, premature loss of gonadal function, decreased estrogen secretion, thin body habitus, decreased physical activity, cigarette smoking, alcohol abuse, excess glucocorticoid exposure, and possibly some genetic factors. Osteoporosis in ESRD patients is only a part of a wider spectrum of metabolic bone problems, namely uremic osteodystrophy. Therefore, its diagnosis, management and follow-up may differ from the general population and an individualization of diagnosis and definition for dialysis population may be necessary. However, standard diagnostic tools such as dual energy X-ray absorptiometry (DEXA) have been widely used for the assessment of bone mineral deficiency status in ESRD patients. Regardless of the methods, most of the studies are in concordance with a reduced BMD in HD and PD patients. Dialysis patients are known to be at increased risk for low-trauma fractures. Thinning of cortical bone, which is responsible for the largest contribution toward reduced bone mineral content in chronic renal failure results in increased fracture risk. In either normal population and dialysis patients, fracture risk is increased with age. But in dialysis patients, besides age, several other factors may also affect the degree of bone mineral deficiency, and age-BMD relationship may be blunted. Female sex, in hemodialysis patients is negatively associated with total hip BMD. While several studies have been unable to demonstrate any association between BMD and PTH levels, larger body size has been shown to have a significant positive effect on BMD in both hemodialysis and peritoneal dialysis patients. Although they have been used in small groups of chronic kidney disease (CKD) and ESRD patients, because of their potential nephrotoxicity and hypocalcemic effects, use of biphosphonates in renal patients is questionable. Currently, bone biopsy, in order to exclude adynamic bone disease is recommended before beginning treatment with bisphosphonates in chronic kidney disease and dialysis patients.

Severe vitamin D deficiency in chronic renal failure patients on peritoneal dialysis.

UNLABELLED: The aim of this study was to evaluate the prevalence of vitamin D deficiency in chronic renal failure (CRF) patients on peritoneal dialysis (PD) and to correlate the findings with various demographic and renal osteodystrophy markers. METHOD: This cross-sectional, multicenter study was carried out in 273 PD patients with a mean age of 61.7 +/- 10.9 years and mean duration of PD 3.3 +/- 2.2 years. It included 123 female and 150 male patients from 20 centers in Greece and Turkey, countries that are on the same latitude, namely, 36-42 degrees north. We measured 25(OH)D3 and 1.25(OH)2D3 levels and some other clinical and laboratory indices of bone mineral metabolism. RESULTS: Of these 273 patients 92% (251 patients) had vitamin D deficiency i.e. serum 25(OH)D3 levels less than 15 ng/ml, 119 (43.6%) had severe vitamin D deficiency i.e., serum 25(OH)D3 levels, less than 5 ng/ml, 132 (48.4%) had moderate vitamin D deficiency i.e., serum 25(OH)D3 levels, 5-15 ng/ml, 12 (4.4%) vitamin D insufficiency i.e., serum 25(OH)D3 levels 15 - 30 ng/ml and only 10 (3.6%) had adequate vitamin D stores. We found no correlation between 25(OH)D3 levels and PTH, serum albumin, bone alkaline phosphatase, P, and Ca x P. In multiple regression analyses, the independent predictors of 25(OH)D3 were age, presence of diabetes (DM-CRF), levels of serum calcium and serum 1.25(OH)2D3. CONCLUSION: We found a high prevalence (92%) of vitamin D deficiency in these 273 PD patients, nearly one half of whom had severe vitamin D deficiency. Vitamin D deficiency is more common in DM-CRF patients than in non-DM-CRF patients. Our findings suggest that these patients should be considered for vitamin D supplementation.

Assessment and comparison of endothelial function between dialysis and kidney transplant patients.

Dialysis and kidney transplant patients display endothelial dysfunction. Previous studies concerning comparisons of endothelial function in dialysis and kidney transplant patients included subjects with cardiovascular risk factor(s) that alone may lead to endothelial dysfunction. In this study, we compared endothelial function between dialysis and transplant patients who did not show known cardiovascular risk factors that lead to endothelial dysfunction. We studied age- and gender-matched cohorts: 30 hemodialysis (HD), 30 peritoneal dialysis (PD), and 30 kidney transplant patients. We also included 20 age- and gender-matched healthy controls. We assessed the endothelial function of patients and controls by a noninvasive technique. Serum biochemistry profiles of patients were also similar to controls in terms of lipid profile and fasting blood glucose level. Although mean FMD% levels of HD and PD patients were similar (6.6% +/- 3.1% vs 6.8% +/- 3.0%, P > .05), the mean percent of flow-mediated endothelium-dependent dilatation (FMD%) level in transplant patients was higher than those in HD or PD patients (10.50% +/- 3.0% vs 6.6% +/- 3.1% and 6.8% +/- 3.0%, respectively; P < .01). In addition, the mean FMD% level in healthy controls was higher than those in HD, PD, and transplant patients (14.0% +/- 2.3% vs 6.6% +/- 3.1%, 6.8% +/- 3.0% and 10.50% +/- 3.0%; P < .01, respectively). In conclusion, endothelial functions in transplant patients were better than those in dialysis patients.

Effects of some hematological parameters on whole blood tacrolimus concentration measured by two immunoassay-based analytical methods.

OBJECTIVES: Tacrolimus (FK506) is a potent immunosuppressive drug used for prevention of rejection following transplantation. Several methods including immunoassays have been used for monitoring tacrolimus levels. The purpose of the present study was to compare the effects of various hematological parameters on whole blood tacrolimus concentrations which were measured with two different analytical methods, namely the microparticle enzyme immunoassay (MEIA II) and enzyme multiplied immunoassay technique (EMIT). DESIGN AND METHODS: The effects of hematological variables, namely hematocrit (Htc), hemoglobin (Hb), red blood cell (RBC), mean cell volume (MCV), mean cell hemoglobin (MCH), mean cell hemoglobin concentration (MCHC), red cell distribution width (RDW) and platelet (PLT) counts on tacrolimus concentrations (n = 2430 measurements) measured with EMIT (n = 1171) and MEIA II (n = 1259) methods in whole blood samples from kidney or liver or combined kidney-pancreas transplant patients (n = 162) during a 2-year post-transplantation period were compared. RESULTS: The whole blood tacrolimus concentrations measured with MEIA II method were affected much more significantly by hematological parameters than those measured with EMIT method. In MEIA II method, RDW (r = 0.479, P < 0.01) showed a stronger correlation with tacrolimus concentration than Htc (r = -0.239, P < 0.01) in all patients. A negative significant correlation (r = -0.468, P < 0.01) was also observed between the Htc and tacrolimus concentration in patients with Htc values < or =25% in MEIA II method. CONCLUSIONS: The results of the present study suggest that EMIT method might be preferred to MEIA II in determination of whole blood tacrolimus concentrations in anemic transplant patients. For better therapeutic drug monitoring, physicians should be aware of these assay differences. Evaluation of hematologic factors that affect the whole blood concentrations of tacrolimus may be helpful in deciding the dosage of this drug.

Sirolimus as primary immunosuppression agent in kidney transplant recipients: Akdeniz University experience.

OBJECTIVES: Recently usage of sirolimus as the primary immunosuppressant is widening among kidney transplant recipients. We reviewed the clinical follow-up of patients transplanted at our center using sirolimus protocols. METHODS: Sirolimus including primary immunosuppressive treatment protocols were begun in February 2002. Among the 21 patients (15 men, six women) who received sirolimus, six patients were prescribed sirolimus + prednisolone; seven, sirolimus + mycophenolate mofetil + prednisolone; and eight, sirolimus + cyclosporine + prednisolone. The mean age of the patients was 32.9 +/- 7.3 years and the mean posttransplantation follow-up, 13.2 +/- 4.5 months. RESULTS: Three patients experienced acute rejection episodes, which were treated successfully with steroids. None of the patients had either hematologic or wound healing problems. Lymphoceles developed in eight patients. Serum creatinine level was 1.4 +/- 0.5 mg/dL at 12 months. There was a serious increase in serum cholesterol and triglyceride levels starting from the first month posttransplant (total cholesterol levels pretransplant and at 1 month, respectively: 159.3 +/- 29.5 and 255.7 +/- 52.3 mg/dL, P = .0001; triglycerides pretransplant and at 1 month, respectively: 146.9 +/- 89.5 and 215.1 +/- 102.5 mg/dL, P = .001). Despite routine antihyperlipemic treatment those high levels were maintained for 12 months. CONCLUSIONS: We achieved 100% graft and patient survival rates for 1 year among patients who were using sirolimus. But the most important role in defining the morbidity and mortality in this group of patients is cardiovascular events; for this reason the abnormalities in the lipid profile must be taken seriously.

Tacrolimus plus low-dose mycophenolate mofetil in renal transplant recipients: better 2-year graft and patient survival than with a higher mycophenolate mofetil dose.

OBJECTIVES: Mycophenolate mofetil (MMF) has become more widely prescribed in recent years, but its adverse effects on the gastrointestinal system and bone marrow restrict its use in certain settings. The aim of this study was to compare the demographic features and clinical data for 173 renal transplant recipients who received tacrolimus (TAC) plus 1 g/d MMF (group I, n = 112) versus TAC plus 2 g/d MMF (group II, n = 61 patients) over a 2-year period. Each patient received similar TAC doses. METHODS: We compared demographic data and clinical data for each case: acute rejection (AR) episodes, chronic rejection (CR) episodes, death, graft loss, development of posttransplantation diabetes mellitus (PTDM), and posttransplantation hypertension rates. RESULTS: Demographic features were similar. There were also no significant differences between groups I and II with respect to number of AR episodes (17/112 vs 12/61, respectively), number of CR episodes (4/112 vs 1/61, respectively), PTDM, and hypertension rate (P > .05). Kaplan-Meier survival analysis revealed 2-year graft survival rates of 94% in group I versus 83% in group II. The corresponding 2-year patient survival rates were 100% in group I versus 91% in group II. The graft survival and patient survival rates in group I were significantly higher than those in group II (log-rank 0.005 and 0.001, respectively). CONCLUSIONS: The 2-year graft and patient survival rates for the renal transplant recipients in this study suggest that the combination of a full TAC dose with 1 g/d MMF is a better choice than 2 g/d MMF.

Benefits of low dose immunoglobulin in the treatment of refractory CAPD peritonitis and longevity of technical survival on CAPD.

In this study we investigated the long term results of intraperitoneal immunoglobulin (Ig) treatment in continuous ambulatory peritoneal dialyses (CAPD) patients with refractory or relapsing peritonitis. Sixteen CAPD patients (4 female, 12 male) with a mean age of 53 +/- 11 years (40-80), with a mean CAPD duration of 46.2 +/- 4.8 months (17-75) were included in the study. The patients included had a diagnosis of either refractory or relapsing peritonitis unresponsive to appropriate antibiotic therapy. 0.5 g of Ig was added to every exchange bag qid as an adjunctive therapy to the culture based antibiotherapy for 7 days. Intraperitoneal Ig treatment was found to be successful in treating peritonitis in all but one patient. Interestingly, following Ig treatment, long term peritonitis rate decreased significantly compared to the period before treatment (before: 2.2 +/- 0.6 episodes/patient/year vs. after: 0.6 +/- 0.17 episodes/patient/year; P = 0.019). The mean CAPD duration after Ig treatment was 30.5 +/- 5.4 (4-64) months. Out of 16 patients, one patient who was unresponsive, had his catheter removed and was switched to hemodialysis, and four patients with preexisting ultrafiltration failure or inadequate dialysis problems were transferred to hemodialysis after successful treatment of their peritonitis, one patient was transplanted and 10 patients continued on CAPD. We conclude that low dose Ig treatment may be beneficial in the treatment of refractory or relapsing CAPD peritonitis possibly through restoring impaired host defense within peritoneal cavity. This therapy, by preventing further peritonitis attacks, may prolong survival on CAPD.

FGF-23, α-Klotho Gene Polymorphism and Their Relationship with the Markers of Bone Metabolism in Chronic Peritoneal Dialysis Patients.

OBJECTIVE: The aim of the present study was to evaluate the variations of some major bone metabolism markers with reference to klotho gene polymorphism (KGP) and bone mineral density (BMD) values in patients on chronic peritoneal dialysis (CPD). MATERIALS AND METHODS: In 51 CPD patients and 40 healthy persons, assays for intact parathormone (iPTH), fibroblast growth factor 23 (FGF-23), osteoprotegerin (OPG), osteocalcin (OC), procollagen type-1 N terminal propeptide (PINP), beta- crosslaps (beta CTx), tartrate resistant acid phosphatase (TRAP5b), bone alkaline phosphatase (BAP), 1,25(OH)D3, and 25(OH)D3 and α-klotho gene mutations were performed. RESULTS: In CPD patients, 1,25(OH)D3 and 25(OH)D3 deficiency rates were 96% and 94% respectively. iPTH (249 pg/mL vs 39 pg/mL) and FGF-23 (1089 RU/mL vs 153 RU/mL), OPG, OC, PINP, beta CTx, TRAP5b levels were significantly higher in patients. iPTH levels and whole-body BMD values were negatively correlated in patients. The rate of KGP was similar in all groups. CONCLUSION: In CPD patients, besides vitamin D deficiency, high levels of OPG, OC, PINP, beta CTx, TRAP5b were evident. Positive correlation between iPTH levels and BAP and PINP levels suggested a diagnostic value for those markers during the management of CKD MBD. On the other hand, high serum TRAP5b concentrations did not seem to be affected by neither calcitriol treatment nor the severity of hyperparathyroidism. iPTH and FGF-23 levels and whole-body BMD values showed a significant negative correlation. We were unable to show any correlation between KGP and any of the CKD-MBD parameters measured in this study.

Bruton tyrosine kinase gene mutations in Turkish patients with presumed X-linked agammaglobulinemia.

X-linked agammglobulinemia (XLA) is a ptototypical humoral immunodeficiency caused by mutations in the gene coding for Bruton tyrosine kinase (BTK). The genetic defect in XLA impairs early B cell development resulting in marked reduction of mature B cells in the blood. Studies from different countries have demonstrated that approximately 90% of males with presumed XLA bear mutations in BTK. In this study, we report for the first time the occurrence of BTK mutations in Turkey. We performed mutational analysis of the BTK gene in 16 Turkish male patients from 13 separate families with presumed XLA based on abnormally low peripheral blood B-cell numbers (lt; 1%), hypogammaglobulinemia, and recurrent bacterial infections. We found that in nine of the 13 families (69%) a Btk mutation caused XLA. Two of the mutations were previously described, but seven novel mutations were identified: two missense (Y39C, G584R), one nonsense (Q343X), and 4 deletions (1800-1821del, 1843-1847del, 1288-1292del, 291del) resulting in frameshift and premature stop codon. By contrast, no mutations in the BTK gene were identified in the other 4 families. A consanguinity in three of these families raises the possibility that mutations in other autosomal genes which affect early B cell development may contribute to their phenotype resembling XLA.

Altered apoptotic profiles in irradiated patients with increased toxicity.

PURPOSE: A retrospective study of radiation-induced apoptosis in CD4 and CD8 T-lymphocytes, from 12 cancer patients who displayed enhanced toxicity to radiation therapy and 9 ataxia telangiectasia patients, was performed to test for altered response compared to healthy blood-donors and normal cancer patients. METHODS AND MATERIALS: Three milliliters of heparinized blood from each donor was sent via express post to the Paul Scherrer Institute (PSI) for subsequent examination. The blood was diluted 1:10 in RPMI medium, irradiated with 0-, 2-, or 9-Gy X-rays, and incubated for 48 h. CD4 and CD8 T-lymphocytes were then labeled using FITC-conjugated antibodies, erythrocytes were lysed, and the DNA stained with propidium iodide. Subsequently, cells were analyzed using a Becton Dickinson FACScan flow cytometer. Radiation-induced apoptosis was recognized in leukocytes as reduced DNA content attributed to apoptosis-associated changes in chromatin structure. Apoptosis was confirmed by light microscopy, electron microscopy, and by the use of commercially available apoptosis detection kits (in situ nick translation and Annexin V). Data from hypersensitive individuals were compared to a standard database of 105 healthy blood-donors, and a database of 48 cancer patient blood donors who displayed normal toxicity to radiation therapy. To integrate radiosensitivity results from CD4 and CD8 T-lymphocytes after 2 and 9 Gy, z-score analyses were performed. RESULTS: A cohort of 12 hypersensitive patients was evaluated; 8 showed enhanced early toxicity, 3 showed enhanced late toxicity, and 1 showed both. The cohort displayed less radiation-induced apoptosis (-1.8 sigma) than average age-matched donors. A cohort of 9 ataxia telangiectasia homozygotes displayed even less apoptosis (-3.6 sigma). CONCLUSION: The leukocyte apoptosis assay appears to be a useful predictor of individuals likely to display increased toxicity to radiation therapy; however, validation of this requires a prospective study.