What is the place of sclerostin in chronic kidney disease,atherosclerosis, and ageing?

International Urology and Nephrology -     

Public health capacity building in southeastern Europe: a partnership between the Open Society Institute and the US Centers for Disease Control and Prevention.

The political disintegration of former Yugoslavia inaugurated in 1991 resulted in the decentralization of health systems in the federation's successor nation-states. Efforts by the Open Society Institute improved public health planning and management needs consequent to health sector changes. Beginning in Croatia in 2001, the Institute developed ongoing collaborations between Andrija Stampar School of Public Health and the US Centers for Disease Control and Prevention. In 2003 and 2004, it expanded its project to include the republics of Macedonia and of Serbia and Montenegro.     

Advances in pharmacotherapy for hyperphosphatemia in renal disease

Introduction: Hyperphosphatemia in chronic kidney disease (CKD) is considered as an independent risk factor for surrogate clinical end points like vascular calcification (VC) and bone disease, or hard clinical outcomes like cardiovascular events. Various treatment options are available for phosphate removal or reduction. Calcium-based phosphate binders (CBB) with their possible positive calcium balance became culprits for progressive VC and increased mortality risk. Non-calcium-based binders (NCBB) treatment allowed a comparable control of hyperphosphatemia with a lower risk of hypercalcemia and a slower progression of VC. Recent data have shown a 22% risk reduction in all-cause mortality with NCBB compared to CBB treatment. The appropriate timing of phosphate binder initiation in CKD patients is still unclear. Recent reports in patients with CKD stages 3b-4 showed increased VC progression when actively treated compared to placebo and a positive calcium, but no negative phosphate balance.

Areas covered: This review discusses the advantages and disadvantages of the pharmacological options to treat hyperphosphatemia.

Expert opinion: The use of phosphate binders is essential in preventing morbidity and mortality in dialysis patients. The choice of phosphate binder takes into account CKD stage, the presence of other components of CKD-mineral and bone disorders, concomitant therapies and drug side-effect profile.     

Impact of triple pelvic osteotomy on contact stress pressure distribution in the hip joint

Purpose

We studied changes of contact stress distribution in the hip joint after Tonnis triple pelvic osteotomy applied in the treatment of dysplasia and hip joint incongruence in adolescents.

Methods

In a group of 75 patients, 54 (72 %) female, who underwent surgery by triple pelvic osteotomy in adolescence for developmental disorder of the hip and avascular necrosis of the femoral head, a three-dimensional hip joint model was used based on the radiography of the pelvis with hips. The following biomechanical parameters were calculated: resultant hip force normalised to body weight (R/Wb), inclination of the resultant hip force (θ−R), the position of the stress pole (θ), peak contact hip stress (Pmax), and peak contact hip stress normalised to body weight (Pmax/Wb). Gait quality was also assessed.

Results

After surgery the Wiberg CE angle was increased by 17.85° (114 %), resultant hip force normalised to body weight (R/Wb) was decreased by 0.107 (3.3 %), the position of the stress pole was shifted medially by 27.59° (63.5 %), and peak contact hip stress normalised to body weight (Pmax/Wb) was decreased by 2249.74 (55.9 %). Waddling gait was reduced from 17 (23.9 %) to four cases (5.6 %). All changes were statistically highly significant (p<0.01).

Conclusions

The effect of Tonnis triple pelvic osteotomy lies in the improvement of stress distribution across the acetabular cartilage of the hip joint, thus slowing down the degenerative damage of the hip joint.     

Is residual renal function and better phosphate control in peritoneal dialysis an answer for the lower prevalence of valve calcification compared to hemodialysis patients?

Introduction

Cardiac valve calcification (CVC) has long been regarded as a consequence of abnormal calcium–phosphate metabolism in uremic patient associated with increased cardiovascular mortality in this population. We evaluated the association between residual renal function (RRF), phosphate level and valve calcification in peritoneal dialysis (PD) and hemodialysis (HD) patients.

Methods

We studied 30 stable PD patients (60 % males; mean age 57 ± 12.36 years) and 34 HD patients (58.8 % males; mean age 50.8 ± 10.4 years) on renal replacement therapy (RRT) from 6 up to 36 months. The presence of CVC was assessed by standard bi-dimensional echocardiography. RRF was calculated by standard technique.

Results

Valve calcification was more frequently found in HD compared to PD patients (70.6 vs 29.4 %, p = 0.007). Significantly lower phosphate [1.38 ± 0.41 versus 1.99 ± 0.35 mmol/L (p < 0.0001)], a higher RRF [4.09 ± 2.09 ml/min vs 0.62 ± 0.89 ml/min (p < 0.0001)], and older age [57 ± 12.36 years vs 50.8 ± 10.4 years (p = 0.033)] were observed in PD as compared to HD patients. The logistic regression analysis for the presence of valve calcification when adjusted for age and diabetes, with type of therapy, serum phosphate, RRF, CRP, and serum albumin as variables in the model, revealed significant association between the presence of valve calcification and age and RRF. The correlation between phosphate levels and RRF was even stronger in PD patients than in HD patients (r = ?0.704; p = 0.0001) vs (r = ?0.502; p = 0.02).

Conclusions

Our study shows that the residual renal function in PD patients contributes significantly to the maintenance of phosphate balance and may explain the lower prevalence of valve calcification in PD patients compared with HD patients in the period up to first 3 years under renal replacement therapy.     

Protocol biopsies in kidney transplant recipients: histologic findings as prognostic markers for graft function and outcome

The aim of the present study was to identify subclinical and borderline rejections as well as histological markers of chronic allograft nephropathy (CAN) among protocol biopsies performed at 1 and 6 months after living related kidney transplantation to assess their possible implications for graft function. Twenty paired allograft biopsies performed at 1 and 6 months were reviewed according to the Banff scoring scheme. The mean ages of donors and recipients were 59.6 +/- 13.8 and 34.4 +/- 8.7 years, respectively. Among all biopsies only 10% (4/40) showed no histopathological lesions. At the first month borderline rejection was shown in 35% and subclinical rejection in 10% of patients. At 6 months the proportion of findings was even higher, namely, 40% and 30%, respectively. When divided according to donor age, donors above 55 years showed a mean CAN score of 2.33 +/- 1.56 which increased to 5.0 +/- 2.26 on the 6 month biopsy (214.3%). Unexpectedly, the proportion of these changes in the younger donor group also increased by 173.3%, which might have been explained by the greater number of borderline and subclinical rejections in the younger donor group at the 1 month biopsy. In conclusion, 1 month biopsy may be valuable to determine borderline and subclinical rejection and to prognosticate the outcome of renal allograft function. Our findings suggest a greater susceptibility of histological deterioration among the older donor population. However, the presence of an untreated rejection in the younger donor pool leads to a rapid impairment of the graft function accelerating the process of chronic allograft nephropathy.