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Soner Duman

Publications and source records attributed to Soner Duman.

14 recordsLinked to original sources
PubMed2006

Long-term survival rates in haemodialysis patients treated with strict volume control.

METHODS: We analysed the survival of 218 patients (132 male, 86 female, age 48 +/- 15 years) who were treated in our dialysis units since we adopted the strategy of strict volume control without antihypertensive drugs. The mean observation period was 47 +/- 34 (6-140) months. Follow-up was ended because of death (57 patients), transfer to another center (35 patients), continous ambulatory peritoneal dialysis (CAPD) (15 patients) or transplantation (23 patients), while 88 were still under our treatment at the time of writing. RESULTS: Blood pressure (BP) decreased from a mean of 150 +/- 31/89 +/- 16 at the start to 121 +/- 14/75 +/- 8 mmHg at the end of observation (P < 0.001). Only nine patients needed a drug (enalapril) to reach this goal. Cardiothoracic index (CTI) dropped from 0.50 +/- 0.06 to 0.46 +/- 0.05 (P < 0.001). Interdialytic weight gain decreased from 1440 +/- 360 to 930 +/- 240 g/day (P < 0.001). Mortality rate was 68, 2 per 1000 patient-years, better than in most published series. There was a striking influence of age, but also of CTI and systolic BP on survival rate. Patients with CTI > or = 0.48 showed mortality 3.8 times higher than CTI < 0.48 (log rank P < 0.001). Consequently, the mean CTI of the deceased patients was much higher (0.50) than the average of the group (0.46) while their mean BP (123 +/- 16/75 +/- 9 mmHg) was not significantly different from the other patients. We found no increased mortality at low-normal pressure levels (systolic BP between 100 and 130 mmHg), but mortality was increased in small groups of patients whose pressures were lower or higher than these values. Thus, the curve, relating mortality to blood pressure was shifted markedly to the left. CONCLUSIONS: These results strongly suggest that the strategy of 'volume control', also when applied with conventional dialysis times, normalizes BP and increases survival of dialysis patients. Cardiomegaly, as evidenced on the chest X-ray despite normal BP, had a strong negative influence on survival. The large majority of the patients had low-normal BP after long periods of treatment and showed the lowest mortality, favouring the view that target BP should be lower than advised by most authors.

Adolescent↗
PubMed2005

Tuberculosis in renal transplant recipients on various immunosuppressive regimens.

BACKGROUND: Mycophenolate mofetil (MMF) and tacrolimus (TAC) are more potent than conventional immunosuppressive drugs, i.e. azathioprine, cyclosporin and prednisolone, and may be associated with an increase in the incidence of infections in the post-transplantation (post-tx) period. The aim of this study was to determine if the use of either or both of MMF and TAC for immunosuppression in renal transplant recipients increases the prevalence or modifies the clinical presentation of tuberculosis (TB), when compared with conventional therapy. METHODS: The medical records of 443 adult patients who received a kidney transplant between 1994 and 2002 were reviewed retrospectively. Comparisons were made between patients who had conventional immunosuppressive treatments (cyclosporin, azathioprine and prednisolone) or an alternative regimen (including MMF, TAC or both). RESULTS: We found 20 patients (4.5%) to have post-tx TB. There were 13 cases of TB (age 38.9+/-10.6 years) among 328 patients who received conventional immunosuppressants (group I) (4.0%) and seven cases (age 24.2+/-7.4 years) among 115 (6.1%) who received an alternative immunosuppressive regimen (group II) (P>0.05). The patients in group II were younger than the patients in group I (P = 0.002). A significantly higher number of patients in group II developed TB within the first 6 months post-tx (P = 0.042). However, there was no significant difference between the two groups regarding clinical and radiographic presentations or outcomes. CONCLUSIONS: Immunosuppression with TAC or MMF is associated with the development of TB earlier in the post-tx period and in younger patients.

Adult↗
PubMed2005

Skin diseases in Turkish renal transplant recipients.

BACKGROUND: Organ transplant recipients are predisposed to a variety of cutaneous complications due to immunosuppressive therapy. We aimed to determine the prevalence and the clinical spectrum of skin diseases in renal transplant recipients (RTRs). METHODS: One hundred and eleven RTRs were examined at the Renal Transplantation Center in Ege University Hospital between October 1999 and October 2001. The effects of age, gender and duration time after transplantation on cutaneous manifestations were evaluated and the dermatologic manifestations in RTRs were compared with findings in a control group consisting of 100 patients. The t-test, chi2 test and Fisher's exact test were used for statistical analysis. RESULTS: Seventy-five patients (66.4%) had an infection of the skin, 66 patients (58.4%) had drug-related manifestations, and 11 patients (9.7%) had premalignant or malignant skin lesions. Human papilloma virus (HPV) infections were the most common skin lesions. There was no significant relation between age and gender and the incidence of skin diseases in RTRs. The incidence of HPV infections, tinea versicolor and premalignant and malignant lesions increased with the duration of immunosuppression. The incidence of infectious skin diseases, especially HPV infections and tinea versicolor, was higher in the study group than in the control group. CONCLUSIONS: In this study, we observed that cutaneous lesions, especially those caused by infectious diseases, had a higher frequency in RTRs. The findings emphasize the importance of regular dermatological screening in these patients, which can provide early diagnosis and a better quality of life for RTRs.

Adolescent↗
PubMed2004

Patients with failed renal transplant may be suitable for peritoneal dialysis.

BACKGROUND: It has been claimed that patients with late transplant failure returning to peritoneal dialysis have lower patient and technique survival. PURPOSE: In this retrospective study, we aimed to clarify this issue in a large PD population. METHODS: Thirty-four PD patients with a failed renal transplant (FTx) and 82 PD patients who had never received a kidney transplant (Non-Tx) or HD treatment were investigated. All fTx patients were using only steroids (5-10 mg/day) for first 3 months of peritoneal dialysis. The groups were similar regarding to age, sex, residual renal function and KT/V; none of them was diabetic. RESULTS: Ftx group had a higher number of peritonitis attack than Non-Tx group (2.42 +/- 0.41 v 1.61 +/- 0.15, attack per patient, p = 0.013). PET status was not different. One, 3 and 5 year patient survival calculated with the Kaplan Meier method were 93%; 93%; 93% respectively in Ftx and 97%; 89%; 82% respectively in Non-Tx patients. Technique survival was 83%; 77%; 60% in Ftx and 91%; 64%; 48% in Non-Tx patients respectively. CONCLUSIONS: We conclude that PD appears to be a good option for fTx patients. A previous renal transplantation does not adversely affect patient and technique survival. Although the somewhat higher infection risk is of some concern, we did not observe earlier loss of peritoneal functions (high transporter) in the post transplant patients.

Adult↗
PubMed2004

Intraperitoneal enalapril ameliorates morphologic changes induced by hypertonic peritoneal dialysis solutions in rat peritoneum.

Peritoneal fibrosis (PF) is one of the most serious causes of technique failure in long-term peritoneal dialysis (PD). Although the mechanisms responsible for the genesis of PF are not well understood, angiotensin II is known to promote fibrosis and inflammation in various tissues and angiotensin converting enzyme inhibitors (ACEIs) have been shown to attenuate those effects. We previously showed that ACEIs have beneficial effects on peritoneal alterations induced by hypertonic (3.86% glucose) PD solutions. In the present study, we investigated the local effects of intraperitoneal (IP) enalapril on peritoneal alterations induced by 3.86% glucose PD solution in rats on chronic PD. One week after peritoneal catheter insertion, 23 non uremic male rats were randomly divided into two groups: group A (n = 11) received 20 mL 3.86% PD solution twice daily, and group B (n = 12) received 20 mL 3.86% PD solution containing 1 mg/L enalapril twice daily. After 4 weeks of such infusions, we measured net ultrafiltration (UF) volume and obtained samples of visceral peritoneum from the liver for thickness measurement. Net UF was significantly higher (6.6 +/- 0.2 mL vs. 5.6 +/- 0.2 mL) and peritoneal thickness was significantly lower (30 +/- 5 microm vs. 52 +/- 0.8 microm) in group B. We conclude that intraperitoneal enalapril (an ACEI) protects the peritoneal membrane from the effects of hypertonic glucose. This protection might be mediated by enalapril's interference with angiotensin though inhibition of cytokine overexpression.

Angiotensin-Converting Enzyme Inhibitors↗
PubMed2002

Successful treatment of post-transplant Kaposi's sarcoma by reduction of immunosuppression.

BACKGROUND: The aim of this study was to investigate retrospectively the clinical presentation, the efficacy of reducing immunosuppression and the consequences of this therapeutic approach in Kaposi's sarcoma (KS) developing after renal transplantation. METHODS: We reviewed the records of 502 patients who had been followed up at our transplantation unit between October 1, 1987 and December 30, 1998. Twelve patients (2.4%) with KS were included in the study. RESULTS: The mean age of KS patients was 38+/-11 years (one female, 11 males). All were on prednisone, azathioprine (AZT) and cylcosporin treatment. KS was encountered at a mean of 18+/-10 months post-renal transplantation. Typical Kaposi's lesions were present in the skin of 11 out of l2 patients. In the only patient without skin involvement, who died from haemophagocytic histiocytic syndrome caused by septicaemia, KS was diagnosed post-mortem in a lymph node. In five patients only skin involvement was present, while the others also had visceral involvement (oropharynx in two patients, trachea and lung in three, lymph node in two, stomach and duodenum in two). Cyclosporin was stopped within 1 month after KS diagnosis, and AZT was stopped in three patients. Both cutaneous and visceral KS manifestations disappeared and no patient was lost due to KS. During a follow-up period 46+/-19 months, KS recurred in the lungs in one patient together with lung tuberculosis, while he was on prednisone and AZT. Two patients lost their graft due to chronic rejection. The remaining eight patients currently have a functioning graft with a mean creatinine level of 1.4+/-0.5 mg/dl. CONCLUSION: KS is the most frequent post-transplant neoplasia (80%) in our country. In the present study cohort, half of the patients had visceral involvement. Reduction or discontinuation of immunosuppression caused complete remission in all patients without surgical intervention, chemotherapy or radiotherapy.

Adult↗
PubMed2002

Strict volume control in the treatment of nephrogenic ascites.

BACKGROUND: Nephrogenic ascites refers to the condition of refractory ascites of unknown aetiology and occurs mainly in patients with end-stage renal disease who are undergoing haemodialysis. Despite many treatment modalities, nephrogenic ascites remains difficult to control and has a poor prognosis. METHODS: We investigated six such patients who had developed severe, apparently refractory ascites during haemodialysis. They all had seriously disturbed cardiac dimensions and function. They were treated with repeated isolated ultrafiltration and severe salt restriction, while their cardiac functions were monitored with echocardiography. RESULTS: After a mean of 18+/-4 l of fluid per patient was removed in 27+/-8 days, ascites disappeared in all patients. Blood pressure and cardiothoracic indices were decreased from 130+/-20/83+/-10 to 95+/-11/60+/-6 mmHg (P<0.02) and from 0.61+/-7 to 0.47+/-5 (P<0.02), respectively. At the end of treatment, heart rates had decreased from 102+/-10 to 85+/-6 beats/min. Previously increased left atrial diameters, end-systolic and end-diastolic dimensions of the left ventricles, and right ventricular diameters reached normal values. Ejection fractions initially decreased in all patients, and then increased slightly to markedly after treatment. CONCLUSION: Nephrogenic ascites is a component of right-sided cardiac congestion mediated by volume overload, and it should be treated with severe salt restriction and frequent ultrafiltration with haemodialysis and, if that fails, with daily isolated ultrafiltration.

Adult↗
PubMedDate not supplied

Paradoxical rise in blood pressure during ultrafiltration is caused by increased cardiac output.

BACKGROUND: In some haemodialysis patients, blood pressure increases during the dialysis session despite ultrafiltration (UF). METHODS: We investigated six such patients who were not responsive to hypotensive drugs. Their echocardiograms were obtained prior to and during the dialysis session. RESULTS: After the mean 2520 +/- 1698 (4.5 +/- 2.3% of BW) ml of fluid was removed, the cardiac systolic function parameters significantly improved and maximum mean arterial pressure rose (from 107 +/- 5 to 118 +/- 6 mmHg, p < 0.027). This increase in blood pressure was accompanied by an increase in cardiac index (from 3.8 +/- 0.6 to 4.8 +/- 1.1 L/min/m2, p < 0.027). With continuing UF, after a mean fluid removal of 4133 +/- 1622 (7.5 +/- 2.1% of BW) ml, normal blood pressure was achieved in all patients. Previously increased ejection fraction and fractional shortening decreased. End-diastolic volume significantly decreased from 98 +/- 34 to 78 +/- 35 ml/m2 indicating normovolemia. This decrease in blood pressure was accompanied by a return of cardiac index to normal values (from 4.8 +/- 1.1 to 3.1 +/- 0.8 L/min/m2, p < 0.027). There was a positive correlation between mean arterial pressure and cardiac index (r = 0.56, p = 0.017). CONCLUSION: We hypothesize that our patients had passed the top of the Frank-Starling curve and were on the descending limb at the initial examination. With UF, patients first shifted to the left and upward on the curve. With further UF, they came down the ascending limb of the curve. In conclusion, paradoxical blood pressure rise during UF is caused by increased cardiac output, mediated by volume overload and can be treated by intensified UF.

Adult↗
PubMedDate not supplied

By reducing production of vascular endothelial growth factor octreotide improves the peritoneal vascular alterations induced by hypertonic peritoneal dialysis solution.

OBJECTIVE: Chronic peritoneal dialysis (PD) may eventually result in vascular alterations of varying degree, which lead to progressive reduction in dialytic efficacy. Although the pathogenesis has not been elucidated yet, vascular endothelial growth factor (VEGF) has been proposed to play a central role in the process leading to vascular alterations. DESIGN: Rats were allocated to three groups: no treatment, intraperitoneal introduction of hypertonic PD solution alone, and intraperitoneal introduction of hypertonic PD solution plus octreotide. After 4 weeks, a 1-hour peritoneal equilibration test (PET) was performed. Dialysate-to-plasma urea ratio (D/P urea), glucose reabsorption (D1/D0 glucose), ultrafiltration volume (UF), and levels of dialysate protein and VEGF were determined. Peritoneal membrane histology was evaluated by light microscopy. RESULTS: Compared with the control group, rats treated with hypertonic PD solution showed dramatically deranged peritoneal function tests (UF: 5.8 +/- 0.9 mL vs 1.3 +/- 0.6 mL; D/P urea: 0.49 +/- 0.1 vs 0.74 +/- 0.04; D1/D0 glucose: 0.55 +/- 0.05 vs 0.34 +/- 0.06) and morphology (thickness: 4.6 +/- 0.4 mu vs 62 +/- 12 mu; neovascularisation: 0.1 +/- 0.3 vessels per field vs 2.2 +/- 0.3 vessels per field). Similarly, a higher level of VEGF was found in the rats treated with hypertonic PD solution. In rats treated with hypertonic solution plus octreotide, peritoneal thickness was not completely reduced (25 +/- 5 mu), but peritoneal functions were protected (UF: 4.0 +/- 0.5 mL; D/P urea: 0.58 +/- 0.02; D1/D0 glucose: 0.51 +/- 0.02). Moreover, VEGF level and neoangiogenesis were significantly less in the octreotide group than in the group treated with hypertonic dextrose alone. CONCLUSION: Our data document that, by increasing the production of VEGF, a high glucose concentration can cause vascular alterations within the peritoneal membrane. Octreotide can protect against the vascular alterations and preserve peritoneal function by inhibiting overexpression of VEGF and regulating the inflammatory response in the peritoneum.

Animals↗
PubMedDate not supplied

Impact of volume control on left ventricular hypertrophy in dialysis patients.

BACKGROUND: Left ventricular hypertrophy (LVH), which strongly predicts cardiac mortality, is seen in more than 60% of end-stage renal disease patients. The aim of this study was to prospectively investigate the effect of salt restriction and strict volume control on blood pressure and LVH. METHOD: Nineteen hypertensive patients on chronic hemodialysis (HD) treatment (age 52 +/- 17 years, 7 women) were included in the study. Treatment consisted of 12-h HD per week, during which as much ultrafiltration (UF) was applied as possible without an excessive blood pressure (BP) drop. Special attention was given to dietary salt restriction. Predialysis mean BP (MBP), body weight (BW), cardio-thoracic index (CTI) and echocardiographic results were recorded at baseline and after 6 and 12 months. RESULTS: All patients reached acceptable BP (< 140/90 mmHg) within three months (10-75 days) with our strict volume control strategy. Mean pre-dialysis BP was 127 +/- 17/78 +/- 9 mm Hg at baseline, 120 +/- 9/75 +/- 6 mm Hg at the 6th month and 118 +/- 11/73 +/- 5 mm Hgat the 12th month. The incidence of symptomatic hypotension gradually decreased from a mean of 22% to 11% and 7%, respectively during follow-up. Left ventricular mass index decreased from 164 +/- 64 to 112 +/- 36 g/m2. CTI, left atrial, left ventricular systolic and diastolic diameters significantly decreased in all patients. Inter-dialytic weight gain was 930 +/- 70 g/day in the follow-up period. Hematocrit did not significantly differ at the first, second and last visits. CONCLUSION: Normal BP and improvement of cardiac structure, in particular a reduction of LVH could be reached in all our patients by intensifying salt restriction and UF.

Adult↗
PubMedDate not supplied

Volume control associated with better cardiac function in long-term peritoneal dialysis patients.

BACKGROUND: This study was undertaken to investigate the effect of long-term blood pressure (BP) reduction, achieved with salt restriction and strict volume control, on frequency and regression of left ventricular hypertrophy (LVH) in long-term peritoneal dialysis (PD) patients. METHODS: 56 patients who had been treated for more than 2 years under our care were enrolled. After echocardiographic (Echo) evaluation, 46 patients were included in the follow-up study. In our unit, we aim to keep patients' BP below 130/85 mmHg and cardiothoracic index below 0.50. To reach these targets, moderate salt restriction is advised, and if necessary, hypertonic PD solutions are used. Echo was performed at the beginning of the study (after a mean period of 36 months on PD) and at the end of the prospective follow-up period (24 months later). RESULTS: At the time of the first Echo, LVH was detected in only 8 (21%) patients. Residual urine volume was significantly decreased compared to data taken when they first started PD (658 +/- 795 vs 236 +/- 307 mL/day). Mean left ventricular mass index (LVMI) was 107 +/- 26.5 g/m2. LVMI was significantly decreased at the end of the follow-up in patients who had LVH at baseline. No LVH developed in patients who had normal LVMI at baseline. CONCLUSION: Our results indicate that control of hypertension is possible when extracellular fluid volume is kept under control using hypertonic PD solutions in case of recruitment in addition to salt restriction in long-term PD patients. Sustained normovolemia is associated with low incidence and regression of LVH.

Adult↗
PubMedDate not supplied

High-dose immunoglobulin therapy in renal transplant recipients with hemophagocytic histiocytic syndrome.

BACKGROUND: Hemophagocytic histiocytic syndrome (HHS) generally occurs in immunocompromised patients and often has a rapidly fatal course. HHS may be cured by treatment of the underlying disorder, especially when it is triggered by an infection. If no cause has been found, no therapy is known and outcome is poor. The aim of this study was to investigate the clinical course and response to intravenous immunoglobulin treatment in renal transplant patients diagnosed with HHS. METHODS: Thirteen patients who were diagnosed with HHS between 1995 and 2003 were retrospectively assessed. The mean age of HHS patients was 38.6 +/- 10 years (5 women, 8 men). RESULTS: Median time to onset of symptoms after renal transplantation was 15.1 +/- 12.1 months (range 0.5-30 months). The first 2 patients in whom no etiologic factor was found were seen before 1998 and died due to multiorgan failure. HHS was related to an infectious etiology in 6 of 13 patients: tuberculosis (n=3), cytomegalovirus (CMV) infection (n=2), Escherichia coli (E. coli)-associated septicemia (n=1), but HHS was cured by antimicrobial therapy in only 2 of them (1 with tuberculosis, the other with E. coli-associated septicemia). After June 1998, high-dose immunoglobulin (IVIg) therapy was used in 6 patients. HHS was related to an infectious etiology in 2 patients unresponsive to antimicrobial treatment, and of unknown etiology in 4 patients. All of them completely recovered. Before 1998, 2 patients unresponsive to antimicrobial therapy (1 with tuberculosis, the other with CMV) died. They were not given IVIg. CONCLUSIONS: We concluded that when HHS does not respond to treatment of the underlying infection, or is of unknown etiology in immunocompromised patients, high-dose IVIg therapy should be administered.

Adult↗