Evaluation of a new measurement method of indoxyl sulfate in hemodialysis patients.

Indoxyl sulfate (IS) is related to the development of cardiovascular disease and total mortality in dialysis patients. High-performance liquid chromatography (HPLC) is the conventional measurement approach. However, the HPLC method is difficult to perform in real time. Recently, the IS Assay Kit "NIPRO", which enables the measuring of total IS by the enzyme method, was developed. This new reagent allows the easy and quick measurement of many samples using the automatic biochemical analyzer. Moreover, it was reported that it demonstrated satisfactory analytical performance. If this enzyme method is useful for measuring IS in hemodialysis, we can expect that the mechanism in which the IS effects adversely on a body as uremic toxins will be clarified. However, the enzyme method is more easily influenced by other coexisting substances. In this study, we have assessed on how the uremic toxins and anticoagulation effect on this new reagent and evaluate whether it can be put into practice effectively for hemodialysis patients. For the enzyme method, accuracy, simultaneous repeatability, linearity, limit of detection, influence of coexisting materials, and correlation with the HPLC method were examined. Accuracy and simultaneous repeatability were satisfactory, and linearity was good. The limit of detection was acceptable, and there was no influence of coexisting materials. With regard to the correlation, the regression equation was y = 0.947X + 7.987 and the correlation coefficient (r) was 0.972. This new reagent showed sufficient fundamental performance and had a good correlation with the conventional HPLC method for assessing the plasma of dialysis patients.

Pelvic Artery Calcification Score Is a Marker of Vascular Calcification in Male Hemodialysis Patients.

Patients who undergo hemodialysis often suffer from cardiovascular disease (CVD), and evaluation of coronary artery calcification is extremely important. These evaluations are typically conducted using a noninvasive method including electron beam computed tomography (CT) or multi-detector CT, and the Agatston method to calculate the coronary artery calcification score (CACS). However, it is difficult to use for patients undergoing dialysis. Because patients undergoing dialysis is too strong in coronary artery calcification, and results become incorrect. Therefore, we were looking for a calcified evaluation place peculiar to a patients undergoing dialysis. We obtained pelvic artery calcification scores (PACS) using a 64-row multi-slice CT to assess the presence of calcification within a triangular space bordered by bordered by osseous structure. We used the Agatston method to calculate PACS. We compared male patients undergoing dialysis with male patients with normal renal function. Patients undergoing hemodialysis had a significantly higher incidence of pelvic artery calcification than normal controls (79.7% vs. 5.5%). In the dialysis group, CACS was 1660.2 (0-9056.1), and PACS was 48.8 (0-2943.1). We found a correlation between PACS and CACS and between PACS and dialysis period. We found penile artery calcification in male patients undergoing hemodialysis was more than normal controls, and it was possible to quantify PACS using the Agatston method. This study suggested the possibility that PACS became the vascular calcification evaluation method of the hemodialysis patient.