Cardiovascular diseases remain the most frequent cause of morbidity and mortality in patients with chronic kidney disease (CKD). The aim of the study was to assess the association between oxidative stress biomarkers and cardiovascular risk factors and left ventricular hypertrophy in children with CKD. Material and Methods. The studied group consisted of 65 patients aged 1.4–18.6 (mean 11.2) years with stages 1 to 5 CKD. Serum oxidized low‐density lipoprotein (oxLDL), protein carbonyl group, creatinine, cystatin C, albumin, lipids, high‐sensitivity C‐reactive protein, intercellular adhesion molecule‐1, insulin, plasma renin activity, and aldosterone levels were measured. Patients were divided into groups depending on CKD stage. Anthropometric measurements, ambulatory blood pressure (BP) measurements, and echocardiography with left ventricular mass (LVM) calculation were performed. Results. Serum oxLDL strongly correlated with creatinine (R = 0.246; p = 0.048), cystatin C (R = 0.346; p = 0.006), total cholesterol (R = 0.500; p < 0.001), triglycerides (R = 0.524; p < 0.001), low‐density lipoprotein concentrations (R = 0.456; p < 0.001), and 24 hour BP values of systolic (R = 0.492; p = 0.002), diastolic (R = 0.515; p < 0.001), and mean arterial pressure (R = 0.537; p < 0.001). A significant correlation between oxLDL levels and LVM z‐scores (R = 0.299; p = 0.016) was found. Conclusions. Hypertension and dyslipidemia correlated with lipid oxidation in children with CKD. oxLDLs seem to be valuable markers of oxidative stress in CKD patients, correlating with left ventricular hypertrophy.

Background. The aim of this nationwide analysis was to assess the incidence and current treatment profile of arterial hypertension in children undergoing chronic haemodialysis or peritoneal dialysis and attitudes of paediatric nephrologists towards the choice of antihypertensive drugs in their patients. Methods. The study group consisted of 134 children (89 males, 45 females, mean age 10.7±5 years) from all 13 paediatric dialysis centres in Poland. The data were gathered through a questionnaire for each patient dialysed in November 2004. Results. The overall incidence of hypertension in the study group was 55% (74 of 134 patients; 47 males, 27 females). The incidence rate was similar in boys and girls (53 vs 60%) and in those on haemodialysis and peritoneal dialysis (56 vs 54%). Chronic glomerulonephritis as an underlying renal disease was significantly more frequent in the hypertensive than in the normotensive subjects (37 vs 10%, P = 0.004). Residual urine output was higher in normotensives (41 vs 10 ml/kg body weight; P <0.001). Among those treated with antihypertensives: 32% were treated by monotherapy, 36% received two drugs, 22% received three drugs, while 7% received ≥4 drugs. The therapy was effective in only 57% of subjects. We observed no differences in biochemical and clinical parameters between those who responded to the therapy and those who failed to do so. Calcium channel blockers constituted the most frequently administered class of drugs [73% of children; in 43 out of 48 (90%) combined with other drugs, but in 11 out of 24 (46%) as a monotherapy]. In monotherapy, angiotensin-converting enzyme inhibitors and calcium channel blockers were administered most frequently. Conclusion. We conclude that the incidence of hypertension in dialysis children in Poland is high (55%). The effectiveness of antihypertensive treatment is rather low (58%) and the choice of drugs is limited.

Background. It is estimated that 20–50% of adult patients start chronic dialysis therapy without prior contact with a nephrologist. The aim of this nationwide study was to assess clinical and metabolic status of children at the start of chronic dialysis in Poland with regard to the timing of the referral to a nephrologist. Methods. We studied data of 180 children (mean age 14±6 years) undergoing chronic dialysis in 13 (out of 14) dialysis pediatric centres in Poland. Patients were classified as early referrals (ERs) when they entered the dialysis programme at least 1 month after the first referral to a nephrologist or late referrals (LRs) when the dialysis was introduced within 1 month from the first visit. Results. Seventy-nine percent of pediatric patients were referred early (ER) to the dialysis centre and 21% were referred late (LR) and had to start dialysis within a month. When starting dialysis, LR patients had significantly higher levels of urea and phosphate as well as lower calcium and haemoglobin in comparison with ERs. Hypertension, pulmonary oedema, fluid overload, treatment in the intensive care unit (ICU) and body mass index (BMI) below 10th percentile turned out to be more frequent in the LR group. Peritoneal dialysis (PD) was used as the first method of dialysis in 59% of ERs and 46% of LRs. The majority of ER patients was treated in the predialysis period with calcitriol, phosphate binders and low protein diet (84%, 89%, 92% of all children, respectively), and 20% of them received epoetin. In the up to 3 years observation of our initial cohort, we also found that the patients who were referred late were less likely to receive kidney transplant (P = 0.02). Conclusion. The results of the study indicate that the LR to a pediatric nephrologist was associated with poorer clinical and metabolic status of children entering chronic dialysis programmes.