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Siren Sezer

Publications and source records attributed to Siren Sezer.

At least 37 records · Page 2Linked to original sources

Association of the genetic polymorphisms of the renin-angiotensin system and endothelial nitric oxide synthase with chronic renal transplant dysfunction.

BACKGROUND: Chronic allograft dysfunction (CAD) is a complex phenomenon caused by underlying kidney disease and superimposed environmental and genetic factors. We investigated the association of polymorphisms in the genes for angiotensin-converting enzyme (ACE), angiotensinogen (AGT), angiotensin II receptor type 1 (ATR1) and type 2 (ATR2), and endothelial nitric oxide synthase (ENOS) with the initiation of CAD. METHODS: Genotyping was performed in 125 patients who underwent renal transplantation during a 5-year period for the ACE I/D, AGT M235T, ATR1 A1166C, ATR2 C3123A, and ENOS intron 4a/b gene polymorphisms. The following information was collected for each case: date of transplantation, age and sex of donor and recipient, donor type, cold ischemia time, number of human leukocyte antigen mismatches, number of acute rejection episodes, and laboratory findings at discharge from hospital and annual rechecks. Blood pressure was measured at yearly intervals throughout follow-up. RESULTS: The proportions of the genotypes were ACE II/ID/DD 12%, 33.6%, 54.4%; AGT MM/MT/TT 33%, 65.2%, 1.9%; ATR1 AA/AC/CC 68.6%, 30.7%, 0.7%; ATR2 CC/CA/AA 57.9%, 27.5%, 14.4%; and ENOS aa/ab/bb 6.4%, 22%, 71.6%, respectively. Statistical analysis of the major risk factors for the initiation of CAD showed that ACE DD genotype, cadaveric donor type, and level of proteinuria at 1 year posttransplantation were associated with poorer renal function. The graft function was not affected by AGT, ATR1, ATR2, and ENOS gene polymorphisms. CONCLUSIONS: These findings suggest that the DD variant of the ACE gene polymorphism is associated with increased risk of developing CAD.

Adult↗

Acute interstitial nephritis due to cefoperazone.

OBJECTIVE: To describe a case of cefoperazone-induced acute interstitial nephritis (AIN) in which the diagnosis was supported by renal biopsy. CASE SUMMARY: A 35-year-old woman presented to our hospital with decreased urine output and no past history of renal problems. Fifteen days prior to presentation, she had started treatment with intramuscular cefoperazone 1 g/day for a scalp infection. On day 12 of therapy, the patient noted decreased urine output, anorexia, and weakness, but she continued taking cefoperazone for 3 more days. Hemodialysis and oral prednisolone 1 mg/kg (30 mg twice daily) were started. Renal function returned to normal after 2 months of prednisolone treatment. DISCUSSION: Although AIN has been linked with other cephalosporins, as of June 18, 2004, to our knowledge, this is the first report of a cefoperazone-induced case. We based our diagnosis on the features of acute-onset renal failure, abnormal urinalysis findings, eosinophilia, inflammatory infiltrate in the interstitium, and recovery from renal failure after initiation of corticosteroid treatment. Application of the Naranjo probability scale indicated a probable relationship between the acute renal failure secondary to the possible AIN and cefoperazone therapy in this patient. CONCLUSIONS: This case indicates that cefoperazone, like other cephalosporins, can cause AIN. We recommend close monitoring of renal function in patients who are prescribed this drug.

Acute Disease↗

Panel reactive antibody positivity and associated HLA antibodies in Turkish renal transplant candidates.

Pre- and post-renal transplantation panel reactive antibody (PRA) screening is associated with increased incidence of hyperacute or acute graft rejection and graft loss. This study was designed to find any relationship PRA sensitization and associated human leukocyte antigen (HLA)-specific antibodies in Turkish renal transplant candidates. We included 340 patients who were in the renal transplantation waiting list in the study. We determined PRA sensitization ratio and the associated anti-HLA IgG antibody distribution of the patient group. The PRA testing was currently performed and levels above 30% were accepted to be positive. The PRA class I positivity was determined in 24 (7%) and class II in 34 (10%) of the patients. The most frequent HLA antibodies for class I were B56, A2, A34, A1, A23, A24 and B61; and for class II were DR11, DR14, DQ7, DR10, DQ5, DR1 and DR7, respectively. From these, the increase of the numbers of anti-HLA class II antibodies was significantly correlated with the increase of PRA sensitization ratio. In conclusion, the identification of the associated HLA-specific antibodies and correlation with the Turkish population HLA antigen distribution will identify the high-risk patients who are candidates for transplantation.

Antibodies↗

Pulmonary function in uremic patients on long-term hemodialysis.

Twenty patients with end-stage renal failure who were on maintenance hemodialysis (HD) underwent pulmonary function testing (PFT) before and shortly after an HD session. On pre-HD PFT, the mean values of all parameters except residual volume (RV) were in the normal range. Mean RV was high (152.9%), and mean diffusing capacity of the lung for carbon monoxide (DLCO) was high-normal (110.4%). The pre-HD static inspiratory (PImax) and expiratory pressures (PEmax) were much lower than normal (67.4% and 36.3%, respectively). After the HD session, repeat PFT revealed a small increase in expiratory flow rates, and a significant drop in PImax. There was a strong correlation between PImax and PEmax (r=0.567, p<0.01) at the pre- and post-HD stages, indicating that common mechanism(s) are responsible for impairment of both inspiratory and expiratory muscle strength. The well-preserved DLCO was thought to be due to the use of biocompatible dialyzer membranes. Chronic vascular congestion might be the other explanation of high DLCO.

Adult↗

Gabapentin versus levodopa for the treatment of Restless Legs Syndrome in hemodialysis patients: an open-label study.

BACKGROUND: Restless Legs Syndrome (RLS), a common problem increasing morbidity and mortality in hemodialysis (HD) patients, affects 20-30% of uremic patients. Our aim was to find the efficacy of gabapentin in the treatment of RLS in HD patients by comparing a largely used drug, levodopa. METHODS: Patients with RLS answered three questionnaires (RLS rating scale proposed by IRLSSG, the Short Form (SF)-36 and the Pittsburgh Sleep Quality Index) for the evaluation of severity of RLS, effects on quality of life and quality of sleep. RESULTS: Fifteen patients (4.7%) (5 F, 10 M) with a mean age of 45.8+/-15.3 years got RLS diagnosis. When we compare the two drugs for severity of RLS symptoms relief, the effect of gabapentin was more significant (p<0.001). Gabapentin significantly improved general health, body pain and social functions (p<0.001). Moreover, regarding sleep parameters, gabapentin was significantly superior to levodopa for sleep quality, sleep latency (p<0.001) and sleep disturbance (p<0.000). CONCLUSION: To our knowledge this was the first study comparing gabapentin and levodopa efficacy for the treatment of RLS in HD patients. Our results suggested that gabapentin is an effective drug for the management of RLS in hemodialysis patients.

Adult↗

A six-year follow-up after interferon-alpha monotherapy for chronic hepatitis C infection in hemodialysis patients.

Interferon-alpha (IFN) has been accepted as an effective treatment for chronic hepatitis C virus (HCV) infection in hemodialysis (HD) patients. We prospectively assess the long-term clinical, biochemical, and virological effects of interferon in the treatment of HD patients with chronic HCV infection. This study was performed in 20 HCV-RNA-positive HD patients with evidence of chronic hepatitis on liver biopsy. The patients received IFN administered after HD sessions in doses ranging from 3 to 6 million units for 6 to 12 months. The patients were followed up for a period of 6 years with determinations of serial alanine aminotransferase (ALT) levels and serum HCV-RNA. At the time of the final follow-up, the patients had no cirrhosis or hepatocellular carcinoma. Among the nonresponder group, only 1 patient died due to sudden cardiac death. Sustained normal serum ALT levels occurred in 9 (45%) of the patients. Nine patients had variable ALT levels, and 2 patients had persistently elevated ALT levels. Eight (40%) patients were continuously HCV-RNA negative, whereas 12 patients (60%) had variable HCV-RNA results at the end of the 6-year follow-up. These findings show that the long-term clinical, biochemical, and virological response to interferon monotherapy is good in HD patients with HCV infection.

Adult↗

Renal transplantation offers a better survival in HCV-infected ESRD patients.

Sezer S, Ozdemir FN, Akcay A, Arat Z, Boyacioglu S, Haberal M. Renal transplantation offers a better survival in HCV-infected ESRD patients. Clin Transplant 2004 DOI: 10.1111/j.1399-0012.2004.00252. Abstract: The presence of hepatitis C virus (HCV) infection has been found to adversely affect the morbidity and mortality rates in the dialysis population. Renal transplantation is a treatment option after a careful pre-transplant evaluation. We designed this study to find the impact of HCV infection on patient survival, co-morbidity and allograft survival in a selected group of hemodialysis (HD) and transplant population. We retrospectively analyzed 116 renal transplant patients (94 HCV-negative, 22 HCV-positive) and 136 HD patients (106 HCV-negative, 30 HCV-positive) who had renal transplantation or underwent dialysis before 1996. The HCV-infected patients were evaluated by liver biopsy for the absence of advanced liver disease before transplantation. There was no clinical or laboratory decompensation of liver disease in transplant and dialysis patient groups. The overall 5-yr survival rates were 85.2% for renal transplant recipients and 74.5% for those on HD. The comparison results revealed a significant difference between HCV-infected patients with and without transplantation. The 3-yr renal allograft survival rates were comparable in HCV-positive and -negative patients, but the risk of chronic allograft nephropathy (CAN) and graft failure were higher at the fifth year in HCV-positive patients. In conclusion, renal transplantation should the preferred therapy in HCV-infected dialysis patients as it improves the survival rates. The presence of HCV infection increases the CAN rate and the influence on allograft survival is evident at the fifth year of assessment.

Adult↗

Post-transplant C-reactive protein monitoring can predict chronic allograft nephropathy.

Chronic allograft nephropathy (CAN) is a major problem after renal transplantation and chronic inflammation can be one of its promoters. C-reactive protein (CRP) is an important marker of inflammation and atherosclerosis. We retrospectively analyzed the predictive role of serum CRP levels on the development of CAN and graft failure. One hundred and twenty-five renal transplant patients were randomly included into the study. Serum CRP levels were measured at pre-transplant period, first month after transplantation and at yearly intervals throughout follow-up. CAN was diagnosed in 40.8% of patients and 82.4% of them had graft failure in 60.9 +/- 36.7 months. There was no difference at pre-transplant CRP levels of patients with and without CAN, but the first month CRP levels were higher in those who experienced CAN. The initial 3-yr mean CRP levels were higher, but not statistically different between the patients with and without CAN. The simultaneously detected CRP levels when CAN were diagnosed was significantly higher in those with CAN. High post-transplant CRP levels at the first month and at the diagnosis of CAN significantly influenced the allograft failure according to the regression analysis. CRP monitoring gives important information about the risk for CAN and graft failure. Therefore, CRP levels should be included in the follow-up data after renal transplantation.

Adult↗

The association of interdialytic weight gain with nutritional parameters and mortality risk in hemodialysis patients.

High interdialytic weight gain (IDWG) is considered as an indicator of noncompliance but could also be interpreted as an index of appetite. This study was designed to investigate the relationship IDWG with malnutrition and mortality risk in hemodialysis (HD) patients through a follow-up of 24 months. We divided HD patients into two groups according to their IDWG as Group I (IDWG < 3% of dry weight/day) (27 patients; age 46.8 +/- 21.1 years; HD duration: 28.3 +/- 39.5 months) and Group II (IDWG > or = 3% of dry weight/day) (41 patients; age 40.9 +/- 11.3 years; HD duration: 54.7 +/- 38.7 months). We investigated malnutrition through biochemical analysis (albumin, prealbumin, total cholesterol, creatinine, predialysis potassium and phosphorus levels), normalized protein catabolic rate (nPCR), anthropometric measurements. On initial assessment, group I had significantly lower predialysis creatinine, prealbumin and potassium levels than Group II (p < 0.0001, p < 0.01 and p < 0.001, respectively). At the 24th month, there were significantly lower creatinine, prealbumin, potassium and phosphorus levels in the low-IDWG group. Group I had significantly lower nPCR, body weight, body mass index and triceps skinfold thickness during the follow-up. Over the 24 months, 13 (48.1%) Group I patients and nine (21.9%) Group II patients exhibited loss of dry weight (p < 0.02). According to the survival curves prognosis was significantly poorer for Group I than Group II (2-year survival 74.0% and 92.6%, p < 0.03). Group I individuals with low albumin levels had the worst survival rate (57.1%). In conclusion there is a strong association of IDWG with nutritional parameters in HD patients. Our study draws attention for a possible risk of developing malnutrition in a HD patient with low IDWG.

Adult↗

Triad of malnutrition, inflammation, and atherosclerosis in hemodialysis patients.

BACKGROUND/AIM: As chronic inflammation underlies both atherosclerosis and malnutrition, a possible link between these factors has been suggested in hemodialysis (HD) patients. We designed this study to compare nutritional indices and inflammatory parameters of HD patients with demonstrated atherosclerosis (group I) and HD patients without (group II). METHODS: We included 59 and 57 patients in groups I and II, respectively. The patient groups were matched for the risk factors for atherosclerosis such as age, gender, smoking habits, hypertension, and HD duration. The nutritional status of the patients was evaluated according to laboratory parameters, normalized protein catabolic rate, anthropometric measurements, and subjective global assessment. RESULTS: Laboratory parameters (albumin, prealbumin, total cholesterol, phosphorus, creatinine), normalized protein catabolic rate, and triceps skinfold thickness revealed a significant decline in the nutritional status of the patients with atherosclerosis. We found that the patients with atherosclerosis had significantly higher C-reactive protein, ferritin, and fibrinogen levels when we compared the patient groups for acute-phase reactants. When we assessed malnutrition as being in category B/C (B = mild to moderately malnourished, C = severely malnourished) according to subjective global assessment and inflammation on the basis of a C-reactive protein level > or =10 mg/l, among patients with atherosclerosis, there was a significantly higher proportion of them having malnutrition and inflammation. Additionally, the proportion of patients without any evidence of malnutrition and inflammation was significantly lower in group I than in group II. CONCLUSION: Our study gives evidence for the possible triad of malnutrition, inflammation, and atherosclerosis in HD patients.

Adult↗

Doppler tissue imaging of the heart in secondary amyloidosis.

Secondary amyloidosis (SA) affects cardiac texture and function by interstitial fibrosis. Doppler tissue imaging (DTI) may quantify heart function through the assessment of myocardial velocities. Echocardiographic findings of early cardiac amyloidosis (CA) without heart failure (HF) caused by SA were determined both by standard methods and DTI. It was then determined whether DTI is superior to conventional echocardiography in documenting early CA due to SA. Twenty-five patients with SA who had CA without HF (group 1) were compared with 25 healthy control subjects (group 2). After standard echocardiography, systolic (s), early (e) and late diastolic (a) velocities of interventricular septum, anterolateral, and anterior and inferior walls were measured from mitral annulus by DTI. The averages were called (s(mean)), (e(mean)), and (a(mean)), respectively. Fractional shortening (FS) and ejection fraction (EF) values of groups 1 and 2 were similar. Standard Doppler echocardiographic values were not typical for a specific diastolic abnormality. The (s(mean)) and (e(mean)) for group 1 were lower but (a(mean)) was higher compared with group 2 (all P < .05). The group 1 (e(mean)/a(mean)) was lower (P < .0001) and (E/e(mean)) was higher (P = .003) than in group 2 (both P < .05). (E/e(mean)) and (E/e(lateral wall)) ratios were positively correlated (r = 0.74, P < .05). In patients with early CA due to SA without HF, by DTI, (s(mean)) and (e(mean)) velocities decrease and (a(mean)) velocity increases. These may be markers of subclinical CA of SA when standard echocardiography is not informative. (E/e(mean)) ratio may be an alternative index to (E/e(lateral wall)).

Adult↗

Effects of ACE gene polymorphism on vitamin D therapy according to parathyroid hormone level in patients on hemodialysis.

Medical management is still far from optimal in secondary hyperparathyroidism. This may be explained, at least in part, by genetic differences. The aim of this study was to evaluate the association of genetic influences of angiotensinconverting enzyme (ACE) gene polymorphisms with response to vitamin D therapy among patients on hemodialysis (HD). Eighty-two patients (female/male, 34/48; mean age, 47.5+/-15.3 y; HD duration time, 76.6+/-33.2 mo) with endstage renal disease who were on maintenance HD were included in the study. Five-year retrospective demographic, clinical, laboratory, and treatment data (5-y cumulative doses of phosphate-binding drugs and oral and intravenous cumulative doses of active vitamin D) were retrieved from patients' hospital records. ACE gene polymorphisms of patients were documented and were used to group patients as follows: The insertion/deletion polymorphism group (I/D) consisted of (1) group non-DD (n=43), who had the DI or II allele, and (2) group DD (n=39), who had the DD allele. Patients with the DD allele (group DD) of ACE gene polymorphism had (1) significantly elevated mean 5-y intact parathyroid hormone levels when compared with the non-DD group (P=.009), and (2) significantly elevated oral and intravenous 5-y cumulative doses of vitamin D. Oral and intravenous 5-y cumulative doses of vitamin D used in group DD patients were significantly higher than those in group I patients (P=.038 and P=.037, respectively). Knowledge of genetic differences among patients on HD may be useful to the clinician in planning treatment strategy. ACE gene polymorphism may have an effect on hyperparathyroidism, as is seen in patients on HD. Patients from this group who have resistant hyperparathyroidism may be candidates for ACE inhibitor therapy.

Female↗

Effect of simvastatin in the treatment of highly sensitized dialysis patients: the pre and post-renal transplantation follow-up outcomes.

The graft survival rates of sensitized kidney recipients have been shown to be lower than non-sensitized patients. Therefore, panel reactive antibody (PRA) and cross-match determination is accepted as mandatory screening for renal transplantation candidates. Our recent previous study has shown that simvastatin had a significant immunosuppressive effect in PRA-positive and/or crossmatch-positive patients. We present the pre and post-transplantation follow-up outcomes of simvastatin treatment in the highly sensitized dialysis patients. Thirty patients were followed for a mean period of 26 months. The PRA and flow cytometric measurements were performed at monthly intervals. Ten patients underwent successful kidney transplantation (eight living-related and two cadaveric). None of the patients developed hyperacute or acute rejection, and there was no graft loss during 19.8+/-6.2 months of post-transplantation follow-up. Of the 18 patients who stayed on dialysis throughout the study with PRA positivity, six were lost to follow-up and three spontaneously stopped taking the simvastatin. In the latter three cases, the PRA levels rose significantly after the drug was discontinued. Eight of the remaining nine PRA-positive patients showed significant drops in mean PRA level over the study period, and entered the range considered acceptable for transplantation. Only one patient showed persistently high PRA levels throughout the study. In one patient, the drug had to be discontinued due to acute toxic hepatitis. In conclusion, the results indicate that continuous simvastatin therapy effective in immunized and highly sensitized dialysis patients. Meanwhile, it has beneficial effect on 1-year graft survival in sensitized renal transplantation group.

Adult↗

Hepatic subcapsular steatosis as a complication associated with intraperitoneal insulin treatment in diabetic peritoneal dialysis patients.

OBJECTIVES: The aim of this study was to evaluate hepatic subcapsular steatosis (HSS) and its association with clinical parameters in nondiabetic continuous ambulatory peritoneal dialysis (CAPD) patients and in diabetic CAPD patients receiving intraperitoneal (IP) or subcutaneous (SC) insulin. DESIGN: Cross-sectional study. SETTING: A tertiary-care university hospital. PATIENTS: 28 CAPD patients (17 males and 11 females; mean age 53.5 +/- 14 years; mean CAPD duration 22.8 +/- 9 months) were included in the study. 14 patients had type II diabetes mellitus and 14 were nondiabetics. In the diabetic group, 8 patients were receiving IP insulin and 6 were receiving SC insulin. OUTCOME MEASURES: HSS was diagnosed on computed tomography without contrast administration. Other data collected were body mass index (BMI), weekly Kt/V, peritoneal equilibration test (PET) results, daily insulin dosage, duration of diabetes mellitus, duration of insulin treatment, dialysate glucose load, and serum findings for alanine aminotransferase, aspartate aminotransferase, albumin, and lipid profiles. RESULTS: HSS was detected in 5 of the 8 diabetics who were receiving IP insulin. None of the diabetics receiving SC insulin and none of the nondiabetic patients exhibited HSS. Daily insulin dosage [108 (95 - 108.5) vs 54 (36 - 72) U/day, p = 0.02], BMI [31 (30.5 - 36) vs 26.6 (26 - 30) kg/m2, p = 0.02], serum triglyceride level [194 (184 - 505) vs 69 (61 - 82) mg/dL, p = 0.04], and PET creatinine levels [D/P2 creat: 0.67 (0.54 - 0.74) vs 0.50 (0.50 - 0.56), p = 0.05; D/P4 creat: 0.75 (0.64 - 0.86) vs 0.60 (0.59 - 0.62), p = 0.02] were higher in diabetic patients receiving IP insulin who had HSS than in those who did not have HSS. PET glucose levels [D0/D2 glu: 0.40 (0.37 - 0.45) vs 0.50 (0.48 - 0.51), p = 0.03; D0/D4 glu: 0.36 (0.26 - 0.38) vs 0.44 (0.38 - 0.48), p = 0.04] were lower in diabetic patients receiving IP insulin who had HSS than in those who did not have HSS. CONCLUSIONS: Our results suggest that IP insulin plays a more important role in the pathogenesis of HSS than glucose levels in diabetic CAPD patients. They also indicate that HSS is associated with higher daily insulin requirement, obesity, hypertriglyceridemia, and high peritoneal transport rate in diabetic CAPD patients receiving IP insulin.

Alanine Transaminase↗

Malnutrition-inflammation score is a useful tool in peritoneal dialysis patients.

BACKGROUND: Malnutrition-Inflammation Score (MIS) is a quantitative assessment tool based on Subjective Global Assessment (SGA) and predicts mortality and morbidity in maintenance hemodialysis patients. However, there are not enough data about the use of MIS in peritoneal dialysis (PD). In this study, relationships between MIS and prospective hospitalization indices, risk of developing peritonitis, anemia indices, and laboratory and anthropometric parameters were analyzed and compared with SGA in PD. METHODS: 50 PD patients (M/F 26/24, age 45.2 +/- 14.9 years, mean PD duration 30.8 +/- 23.1 months) were included. The same physician performed the SGA and MIS evaluations. Clinical, laboratory, and anthropometric parameters were measured. RESULTS: 18 patients were classified as SGA-A (without malnutrition), 24 as SGA-B (with moderate malnutrition), and 8 as SGA-C (with severe malnutrition). Increment in MIS was concordant with SGA groups A to C (p < 0.0001). Peritonitis rate, number of hospitalizations, total number of hospitalization days, erythropoietin requirements, C-reactive protein (CRP), and ferritin levels were positively correlated with MIS (p < 0.0001). Midarm muscle circumference (p = 0.04), albumin (p < 0.0001), prealbumin (p = 0.001), creatinine (p = 0.04), hemoglobin (p = 0.003), transferrin (p < 0.0001), and cholesterol (p = 0.009) were negatively correlated with MIS. Correlation coefficients of hospitalization indices, peritonitis rate, anemia indices, erythropoietin requirements, albumin, prealbumin, CRP, and anthropometric parameters were higher with MIS than with SGA. In logistic regression analysis, a higher MIS was independently associated with a higher risk of future hospitalization (p = 0.029, odds ratio 2.14, confidence interval 1.082-4.146). CONCLUSIONS: This study demonstrated that MIS significantly correlated with clinical, nutritional, inflammatory, and anthropometric parameters and anemia indices in PD patients, and that those correlations were stronger than those with SGA.

Adult↗

Acute tubulointerstitial nephritis and acute leukemia: report of 2 cases.

Acute tubulointerstitial nephritis usually develops due to either acute infection of kidneys or delayed hypersensitivity reaction to medication and may rarely be associated with acute renal failure. The disease may very rarely be associated with hematologic/neoplastic diseases. Tubulointerstitial nephritis associated with leukemia is usually due to chemotherapeutic agents or viral infections of the severely immuno-compromised host mostly after bone marrow transplantation. We herein report 2 cases of acute tubulointerstitial nephritis associated with acute leukemia. To our knowledge, the cases are the first in literature in which acute tubulointerstitial nephritis was simultaneously diagnosed with acute leukemia without any chemotherapeutic insult or apparent viral infection. Despite the usual asymptomatic nature of the disease process, the cases are original in that acute tubulointerstitial nephritis associated with acute leukemia resulted in acute renal failure in both cases and hemodialysis was inevitable in one.

Acute Disease↗