Ewa Król

Tonic chemoreflex activation contributes to the elevated muscle sympathetic nerve activity in patients with chronic renal failure

Objective Sympathetic activation may contribute to both cardiovascular morbidity and the progression of chronic kidney disease. The role of the chemoreceptors in determining sympathetic nerve discharge in patients with chronic renal failure (CRF) is unknown. We tested the hypothesis that tonic activation of excitatory chemoreceptor afferents contributes to the elevated sympathetic activity in patients with CRF. Methods Utilizing a double-blind, randomized, vehicle-controlled design, we examined the effects of chemoreflex deactivation on muscle sympathetic nerve activity (MSNA). We compared effects of breathing 100% oxygen for 15 min with effects of breathing room air for 15 min in 12 stable patients with CRF and in 12 control individuals with similar age, gender, blood pressure and body mass index. Results The baseline MSNA was elevated significantly in the patients with CRF as compared with the control individuals (50 ± 2 vs 42 ± 2 bursts/min; P < 0.05). Reductions in systolic blood pressure and pulse pressure in response to the administration of 100% oxygen were significantly different from those observed during administration of room air in patients with CRF. In patients with CRF, MSNA decreased by 29 ± 7% (P < 0.01) during hyperoxia but did not change during administration of room air (5 ± 6%; P = NS). By contrast, neither 100% oxygen or room air changed any measures in control individuals. Conclusions Tonic activation of excitatory chemoreflex afferents contributes to increased efferent sympathetic activity to muscle circulation and to blood pressure control in patients with CRF. These findings may have important implications for understanding mechanisms underlying the link between CRF and cardiovascular disease.

Hemolytic anemia after renal transplantation: analysis of case reports.

Hemolysis after renal transplantation in some cases is clearly related to hemolytic-uremic syndrome (HUS) and usually attributed to cyclosporine (CsA) treatment. Acute hemolysis in other recipients is related to anti-erythrocyte autoantibodies. In most cases these patients have received ABO-compatible, although ABO-nonidentical, organs, mostly from O blood group donors. We report three cases of autoimmune hemolytic anemia after renal transplantation. Two patients (patients: 1 and 2; ABO-compatible, but nonidentical kidneys) suffered acute hemolysis in the third week after transplantation. One patient (patient 3: ABO-identical kidney) suffered a chronic, subclinical course of disease beginning 5 months after transplantation. The clinical picture of this disease was completely different from HUS. The existence of severe anemia (patients 1 and 2), hyperbilirubinemia (particularly high in patient 3), increased serum lactic dehydrogenase levels, and decreased serum haptoglobin in the presence of good graft function suggested an hemolytic anemia. In all patients the direct antiglobulin test was positive. The acute or chronic symptoms of hemolysis disappeared, at 2 and 5 weeks, respectively, after conversion from CsA to tacrolimus. Hemolysis in these patients probably relates to alloantibodies derived from passenger B lymphocytes transplanted with the organs. Because hemolysis has been most frequently related to CsA therapy, it is suggested that B lymphocytes proliferated and produced antibodies because CsA effects to inhibit T-cell function generally spares B-cell activity. It is proposed that a subtype of B cells, which are resistant to CsA, produces anti-A and/or anti-B antibodies. Treatment with tacrolimus appears to be successful, probably due to its alternate, and likely more effective, manner of B-cell suppression.

Epidemiology of Chronic Kidney Disease in Central and Eastern Europe

Background: The world population suffering from end-stage renal disease (ESRD) is growing. The epidemiology of ESRD is relatively well documented, but data on chronic kidney disease (CKD) are missing, especially in Central and Eastern Europe (CEE). Early detection of CKD is important because it allows introduction of the therapy that slows the progression of CKD. The aim of the present study was to estimate the prevalence of CKD and ESRD in CEE. Methods: Our data are based on two independent surveys: one concerns epidemiology of CKD, the other ESRD. Moreover, we present rough results from the pilot study PolNef on early detection of CKD, performed in North Poland. Estimated glomerular filtration rate, albuminuria and ultrasound examination were the main diagnostic tools. Results: Only limited data from South-East Hungary and North Poland were available: the number of CKD patients under nephrological care and on dialysis. According to the PolNef study, using a dipstick test albuminuria was detected in 15.6% of participants but dropped to 11.9% when it was measured using the turbidimetric method. Conclusions: Data concerning epidemiology of CKD in CEE are missing. Epidemiology of ESRD in CEE seems to be similar to that in Western Europe. PolNef is the first study dealing with renal epidemiological problems in CEE. It shows that renal epidemiological problems in CEE are comparable to those of the other parts of the world. Studies concerning CKD epidemiology in different CEE countries are necessary to confirm that the incidence and prevalence of CKD are similar to those in Western Europe and other parts of the globe.

Prevalence of chronic kidney disease in a representative sample of the Polish population: results of the NATPOL 2011 survey

BACKGROUND Chronic kidney disease (CKD) has been proven to be a major risk factor of cardiovascular disease (CVD). Until now, data on the prevalence of CKD among adults in Poland were limited. The NATPOL 2011 survey is a cross-sectional observational study designed to assess the prevalence and control of CVD risk factors in Poland, and the first study capable of evaluating CKD prevalence in adult Polish citizens. METHODS Serum creatinine concentration and the urine albumin-to-creatinine ratio (ACR) were measured in 2413 randomly selected participants (ages 18-79 years) from a national survey study. CKD was diagnosed if the estimated glomerular filtration rate (eGFR) was <60 mL/min/1.73 m(2) or ≥60 mL/min/1.73 m(2) with coexisting albuminuria (ACR ≥ 30 mg/g). Additionally, comorbidities and anthropometric and social factors related to the prevalence of CKD were analysed. RESULTS The prevalence of CKD was estimated at 5.8% [95% confidence interval (95% CI) 4.6-7.2] using Chronic Kidney Disease Epidemiology Collaboration formula. The general prevalence was higher when the MDRD was applied [6.2% (95% CI 4.0-7.6)]. An eGFR <60 mL/min/1.73 m(2) was found in 1.9% (95% CI 1.5-2.5) of the studied population. This was accompanied by low awareness of this condition (14.9%). The frequency of albuminuria was estimated at 4.5% (95% CI 3.4-5.9). Diabetes mellitus (DM) and arterial hypertension (AH) were more frequent among respondents with diagnosed CKD compared with those without CKD [18.5 versus 4.5% (P < 0.001) and 67.8 versus 29.0% (P < 0.001) respectively]. DM and AH were, apart from increasing age, the two greatest risk factors of CKD. CONCLUSION The estimated prevalence of CKD among adults in Poland is 5.8% (∼1 724 960 patients). Its prevalence was lower than expected. CKD is more frequent in older subjects, smokers and people with comorbidities such as AH and DM.

Overweight, obesity, hypertension and albuminuria in Polish adolescents—results of the Sopkard 15 study

BACKGROUND Obesity is a well-known risk factor of many pathologies, including cardiovascular and renal diseases. The prevalence of overweight and obesity has increased markedly in an epidemic way over the past three decades, including a dramatic increase in overweight and obesity among adolescents. METHODS This study is part of the Sopkard 15 programme-a comprehensive analysis of the overall health of middle school students in the age range between 14 and 15 years with particular emphasis on the risk factors of lifestyle diseases, including metabolic syndrome, chronic kidney disease (CKD) and hypertension. Between 2006 and 2010, we examined 889 students (428 girls, 461 boys) 14 years old, and 26% of them attended classes with an extended sports curriculum. From the three separate blood pressure (BP) measurements a mean value of systolic and diastolic BP from the second and third measurements was taken into analysis. Body mass index (BMI), waist-to-height ratio (WHtR) and body fat mass calculated using bioelectrical impedance analysis (BIA), albuminuria and urine albumin-to-creatinine ratio, estimated glomerular filtration rate (eGFR) estimated on the basis of serum creatinine according to Schwartz and abbreviated Modification of Diet in Renal Disease (MDRD) formula were explored. RESULTS In the examined homogeneous population of adolescents, we found 8% of participants to be overweight and a further 8% of participants to be obese. An abnormal BMI was statistically significant and was more often present in girls compared with boys. WHtR values typical for abdominal obesity were reported in 17% of the population, significantly more often in girls 19.8 versus 12.4% in boys, P < 0.02. Albuminuria was detected in 16% of adolescents according to urinary albumin excretion (UAE) compared with 11% by an urine albumin-to-creatinine ratio (UACR) method. A higher number of participants with elevated BP were observed to be statistically significant more often in subpopulations with overweight and obesity compared with adolescents with normal weight. The relationship between obesity and hypertension was also confirmed in participants with an increased WHtR. However, no significant relationship between weight disturbances (BMI), as well as abdominal obesity (WHtR), and albuminuria was identified. CONCLUSIONS Overweight and obesity are present in a significant proportion of adolescents from a general, healthy population of middle school students in the age of 14 years. This phenomenon is strictly connected to the presence of hypertension.

Pregnancy after kidney transplantation: a single-center experience and review of the literature.

After kidney transplantation (KT), pregnancy is possible, although the risk of maternal and fetal complications is much higher than in the general population. Outcome of 22 pregnancies in 17 patients transplanted in the Gdańsk center in the period 1980-2012 was studied. Mean maternal age at pregnancy was 30 ± 5 (range, 23-39) years, interval between transplantation and conception 3.4 ± 2.5 (range, 0.6-11) years. Mean creatinine concentration before conception was 1.29 ± 0.36 (range, 0.8-2.45) mg/dL and was stable during 1 year preceding pregnancy (mean increase, 0.01 mg/dL). Nine of the 17 patients received 1 and 4 received ≥2 antihypertensive drugs, and 1 had proteinuria. Twelve of the 17 patients were primagravidas, 1 was pregnant 3 times, and 14 times. At the time of conception, 20 patients received CNI (14 cyclosporine, 6 tacrolimus), 15 antimetabolites (3 mycophenolate mofetil [MMF], 12 azathioprine), 1 mammalian target of rapamycin inhibitor (mTORi; sirolimus), and all prednisone. MMF and mTORi were discontinued before or during the 1st weeks of pregnancy. Maternal outcome: all survived the pregnancy. None experienced rejection or graft loss as a direct result of pregnancy. Maternal complications included edema (5/17), worsening of blood pressure control (5/17), and worsening (1/17) or new onset of proteinuria (2/17). Mean creatinine decrease during pregnancy was 0.06 mg/dL. Mean creatinine 1 year after pregnancy was 1.49 ± 0.53 mg/dL. There were 12 cesarean sections. Fetal outcomes: 17 live births (2 with serious congenital defects), 2 spontaneous and 1 induced abortion, 2 stillbirths. Mean pregnancy age and neonate birth weights were 35 ± 4 (range, 23-39) weeks and 2,552 ± 629 (range, 1,480-3,420) g, respectively. During mean 8.5 (range, 1-25) years of follow-up after pregnancy, 4/17 patients lost grafts. Grafts were lost in the 3rd to 7th years after pregnancy. We conclude that pregnancy does not exert a direct negative influence on patient and graft survivals; 68% of all pregnancies resulted in delivering healthy neonates.

Renal Dysfunction in Post-Stroke Patients

Background The presence of chronic kidney disease (CKD) is an indicator of a worse long-term prognosis in patients with ischemic stroke (IS). Unfortunately, not much is known about renal function in the population of post-IS subjects. The aim of our study was to assess the prevalence of renal damage and impaired renal function (IRF) in the population of post-IS subjects. Methods This prospective analysis concerned 352 consecutive post-IS survivors hospitalized in Pomeranian stroke centers (Poland) in 2009. In this group estimated glomerular filtration rate (eGFR) according to MDRD (modification of diet in renal diseases) and CKD-EPI (Chronic Kidney Disease Epidemiology Collaboration) formulas and urine albumin/creatinine ratio (ACR) were determined. Results Among survivors decreased eGFR (<60 mL/min./1.73m2 according to MDRD or CKD-EPI) or ACR≥30mg/g were detected in 40.38% (23.07% Men, 55.32% Women; P<0.01). The highest prevalence of IRF was noted in post-IS subjects with atheromatic and lacunar IS. In multivariate analysis the ACR≥30mg/g was predicted by older age, diabetes mellitus (DM) and physical disability (modified Rankin scale 3–5 pts.). The association with reduced eGFR was proved for sex (female), DM and physical disability. Conclusions CKD is a frequently occurring problem in the group of post-IS subjects, especially after lacunar and atheromatic IS. Post-IS patients, mainly the elderly women, with physical disability and diabetes mellitus, should be regularly screened for CKD. This could reduce the risk of further cardiovascular events and delay the progression of IRF.

Level of Education and Knowledge of Skin Cancer Risk Factors in Patients Undergoing Maintenance Hemodialysis

INTRODUCTION An increased risk of skin cancer is particularly important in patients undergoing maintenance hemodialysis (HD), who are potential transplant recipients. In transplant recipients who are exposed to immunosuppressive therapy, neoplastic skin disease my take a more aggressive course. Increased exposure to photoradiation, elderly age, a low skin phototype, sunburn during childhood, and a history of smoking are the main factors contributing to the development of skin neoplasms. Knowledge of these risk factors as well as education on sun protection should be important for such patients. PATIENTS AND METHODS We studied 105 HD patients (57 men, 48 women) with a mean age of 60.8 (range 25-94) years. Knowledge of skin cancer risk factors was assessed on the basis of a questionnaire regarding skin cancer risk factors. RESULTS In the study group, 23.8% of patients claimed that they frequently and intensively engage in sunlight exposure. However, only 11.4% have started to apply sunblockers recently. Sunburn during adolescence was reported by 12.4% patients. Among the patients studied, 65.7% had skin phototype I or II, and only 34.3% had phototype III. In the investigated study group, 55.2% admitted smoking: 30.5% smoked more than 20 pack-years. Among the patients studied only 2.86% could name 3 skin cancer risk factors, 29.5% 2 risk factors, 60% 1 risk factor, and 7.6% could not name any risk factor. CONCLUSIONS The results presented prove that patients undergoing HD lack knowledge regarding skin cancer risk factors, which explains the necessity of education, particularly on the dangers of sun radiation.

Paired Analysis of Outcomes After Kidney Transplantation in Peritoneal and Hemodialysis Patients

BACKGROUND The impact of dialysis modality before kidney transplantation (hemodialysis or peritoneal dialysis) on outcomes is not clear. In this study we retrospectively analyzed the impact of dialysis modality on posttransplant follow-up. METHODS To minimize donor bias, a paired kidney analysis was applied. One hundred thirty-three pairs of peritoneal dialysis (PD) and hemodialysis (HD) patients were transplanted at our center between 1994 and 2016. Those who received kidneys from the same donor were included in the study. HD patients were significantly older (44 vs 48 years), but the Charlson Comorbidity Index was similar (3.12 vs 3.46) in both groups. The groups did not differ significantly with respect to immunosuppressive protocols and number of mismatches (2.96 vs 2.95). RESULTS One-year patient (98% vs 96%) and graft (90% vs 93%) survival was similar in the PD and HD patient groups. The Kaplan-Meier curves of the patients and graft survival did not differ significantly. Delayed graft function (DGF) and acute rejection (AR) occurred significantly more often in the HD recipients. Graft vessel thrombosis resulting in graft loss occurred in 9 PD (6.7%) and 4 HD (3%) patients (P > .05). Serum creatinine concentration and estimated glomerular filtration rate (using the Modification of Diet in Renal Disease guidelines) showed no difference at 1 month, 1 year, and at final visit. On multivariate analysis, factors significantly associated with graft loss were graft vessel thrombosis, DGF, and graft function 1 month after transplantation. On univariate analysis, age, coronary heart disease, and graft loss were associated with death. Among these factors, only coronary heart disease (model 1) and graft loss were significant predictors of death on multivariate analysis. CONCLUSION The long-term outcome for renal transplantation is similar in patients with PD and HD. These groups differ in some aspects, however, such as susceptibility to vascular thrombosis in PD patients, and to DGF and AR in HD patients.

Progression of Chronic Kidney Disease Affects HDL Impact on Lipoprotein Lipase (LPL)-Mediated VLDL Lipolysis Efficiency

Background/Aims: Hypertriglyceridaemia (HTG) and reduction and dysfunction of high density lipoprotein (HDL) are common lipid disturbances in chronic kidney disease (CKD). HTG in CKD is caused mainly by the decreased efficiency of lipoprotein lipase (LPL)-mediated very low density lipoprotein triglyceride (VLDL-TG) lipolysis. It has not been clarified whether HDL dysfunction in CKD contributes directly to HTG development; thus, the aim of this study was to assess the impact of CKD progression on the ability of HDL to enhance LPL-mediated VLDL-TG lipolysis efficiency. Methods: VLDL was isolated from non-dialysis patients in CKD stages 3 and 4 and from non-CKD patients. The VLDL was incubated with LPL at the constant LPL:VLDL-TG ratio, in the absence or presence of HDL. After incubation, the VLDL was separated and the percentage (%) of hydrolyzed TG was calculated. Results: HDL presence increased the lipolysis efficiency of VLDL isolated from CKD and non-CKD patients, for the VLDL-TG> 50 mg/dl. Its effect was dependent on the VLDL-TG and HDL-cholesterol concentrations in the reaction mixtures: the higher the concentrations of VLDL-TG and HDL-cholesterol, the greater the effect. The positive impact of HDL on VLDL lipolysis was modified by CKD progression: the percentage of lipolyzed VLDL-TG in the presence of HDL decreased with a reduction in eGFR (r=0.43, p=0.009), and for patients with stage 4 CKD, no positive impact of HDL on lipolysis was observed. The percentage of lipolyzed TG correlated negatively with apoE and apoCs content in VLDL, and positively with HDL-apoCII, as well as with VLDL and HDL apoCII/ apoCIII ratios. The progression of CKD was associated with unfavourable changes in VLDL and HDL composition; apoE and apoCs levels increased in VLDL with a decrease in eGFR whereas the HDL-cholesterol level decreased. Conclusion: The progression of CKD affects lipoprotein composition and properties, and modulates the positive impact of HDL on VLDL lipolysis efficiency. In CKD patients, HDL deficiency and dysfunction can directly affect hypertriglyceridaemia development.