We measured skin perfusion pressure (SPP) as a screening test for lower limb peripheral arterial disease (PAD) in 90 hemodialysis patients. The accuracy of the test was compared based on the measurement timepoint and measurement site. Measurements were obtained from the dorsal and plantar surfaces of the foot, before dialysis and during the latter half of dialysis (20 minutes before the end of dialysis). The SPP values at each site decreased significantly during the latter half of dialysis. In addition, the SPP values were higher on the plantar surface of the foot than on the dorsal surface of the foot. When the SPP cut‒off value was set at 50 mmHg, the detection rate of PAD on the dorsal surface of the foot was 67.3％ before dialysis and 77.6％ during the latter half of dialysis, while the detection rate of PAD on the plantar surface of the foot was 32.7％ before dialysis and 55.1％ during the latter half of dialysis. In comparisons of test accuracy according to the measurement time points using the timepoint based on receiver operating characteristic (ROC) analysis, the optimal cut‒off value was found to be 64 mmHg before dialysis and 54 mmHg during the latter half of dialysis, regardless of the measurement site. In PAD screening based on SPP during dialysis, it is important to set a cut‒off value that is appropriate for the measurement timepoint.

By measuring the serum levels of alkaline phosphatase isozymes (ALP isozymes) in hemodialysis patients using agarose electrophoresis, we found that the intestinal type accounted for a large proportion of the ALP in the patients’ blood. Among the 78 examined cases (observation period: 12‒65 months), hyper‒ALPemia was detected in 52.6％. The serum levels of the intestinal type varied with blood group and secreted blood type and also changed after food consumption. The intestinal‒type fraction accounted for 2‒50％ of ALP among the hemodialysis patients. Twenty‒three patients exhibited high frequencies of the intestinal type, including 15 of the 16 cases involving B‒type or O‒type blood. Intestinal ALP has no clinical significance, but some cases of hyper‒ALPemia due to the intestinal type alone were encountered. Hyper‒ALPemia due to the bone type was often found in elderly women. Among the cases involving the liver type, some cases also involved the bone and intestinal types. Cases involving similar ALP were composed of different fractions, depending on the time at which the measurements were taken. In addition, there were cases in which the non‒intestinal fraction contained reference‒range levels of the liver and bone types; therefore, it was necessary to examine each case in detail. In future, the method for measuring ALP will change due to increases in the detectability of the intestinal type, although evaluating all three types of ALP is important.

This study aimed to examine the effects of N‒back training during hemodialysis on cognitive function in hemodialysis patients with mild cognitive impairment. Eight hemodialysis patients (one male and seven females) were enrolled in this study. The intervention was performed three times a week, and involved 20 minutes of N‒back training per session for five months. Patients were assessed using the Mini‒Mental State Examination (MMSE), the Japanese version of Montreal Cognitive Assessment (MoCA‒J), the Benton Visual Retention Test (BVRT), the Visual Cancellation Task (VCT), the Symbol Digit Modality Test (SDMT), and the Paced Auditory Serial Addition Task (PASAT). PASAT scores were significantly higher after the intervention, and at 6 months after intervention. BVRT scores were significantly higher at 6 months after the intervention. N‒back training during hemodialysis improved working memory in hemodialysis patients with mild cognitive impairment. The improved cognitive function of the hemodialysis patients was maintained at 6 months after the intervention.

［Aim］ We examined whether a multi‒item automatic biochemical analyzer (BAA) based on the ion‒selective electrode (ISE) dilution method is suitable for measuring dialysate electrolyte levels. ［Method］ The Na, K, and Cl concentrations (mEq/L) of a dialysate containing 140 mEq/L Na, 2.0 mEq/L K, 112.25 mEq/L Cl, and 27.5 mEq/L HCO₃ were measured 10 times using the serum (s) and urine (u) modes of the BAA. The concentrations of a control substance for ensuring accurate dialysate measurements (JCTCM330), which contained 140 mEq/L Na, 1.96 mEq/L K, 109.8 mEq/L Cl, and 28.5 mEq/L HCO₃, and physiological saline were measured in triplicate in the same way. ［Results］ The following Na, K, and Cl concentration measurements were obtained for the dialysate, JCTCM330, and physiological saline using s‒mode and u‒mode, respectively (mEq/L)： dialysate： Na： 139.2 and 138.7 (p＜0.05), K： 2.02 and 2.10 (p＜0.0005), Cl： 110.1 and 112.7 (p＜0.0001)； JCTCM330： Na： 139.1 and 138.4, K： 1.96 and 2.00, Cl： 106 and 108.7； saline： Na： 152.3 and 151.8, K： 0.37 and 0.20, Cl： 150.8 and 152.4. In both modes, the Na, K, and Cl measurements were close to the expected values. S‒mode, which was calibrated with standard serum, produced higher Na values and lower Cl values than u‒mode. ［Discussion］ ISE measure ion activity. The ion concentration is obtained by dividing the ion activity by the relevant ionic activity coefficient. We assume that the measured values were close to the expected values because diluting the sample brought the activity coefficient close to 1 and the proportion of solid components in serum close to 0. Higher Na and lower Cl levels were seen in s‒mode because s‒mode is calibrated with standard serum. ［Conclusion］ The BAA at our hospital is suitable for obtaining dialysate electrolyte measurements, but u‒mode produces lower Na levels, and s‒mode produces lower Cl levels.

Arteriovenous fistulas (AVF) derived from autologous blood vessels are the most common vascular access points used for chronic dialysis in Japan. Although some cases in which AVF creation was unsuccessful have been reported, no large‒scale randomized controlled trials of this approach have been performed in Japan, and no detailed analysis of the factors affecting the initial patency of AVF has been performed. We retrospectively analyzed a group of patients who underwent AVF surgery, and analyzed the factors affecting initial AVF patency. Of the 119 patients studied, 15 had shunt occlusion (12.6％), and a history of deep vein thrombosis was the only factor that was found to significantly affect patency. It is suggested that the presence or absence of thrombotic factors may affect the initial patency rate of AVF more than factors such as sex, age, and a history of diabetes.

A 69‒year‒old male with a dialysis vintage of 44 years successfully underwent aortic valve replacement. His medical history included cervical spinal canal stenosis, carpal tunnel syndrome, left‒sided amyloid arthropathy, and left‒sided severe lower limb ischemia, which had required revascularization on several occasions. Four years earlier, aortic stenosis had been detected, but he had no related symptoms. Two months earlier, dyspnea on effort had appeared, and echocardiography showed that the aortic stenosis had worsened, which was considered to have caused his symptoms. Thus, aortic valve replacement with a bovine pericardial bioprosthetic valve was performed. Marked calcification and dialysis‒related amyloidosis were observed in all 3 leaflets of his aortic valve. He was only discharged 30 days after the operation because he spent a relatively long period in cardiac rehabilitation, although he did not experience any major complications during the perioperative period.