The annual survey of the Japanese Society for Dialysis Therapy Renal Data Registry (JRDR) was conducted for 4,487 dialysis facilities at the end of 2019 among which 4,411 facilities (98.3%) responded to the facility survey and 4,238 facilities (94.5%) responded to the patient survey. The number of chronic dialysis patients in Japan continues to increase every year; it has reached 344,640 at the end of 2019 and the prevalence ratio of dialysis patients was 2,732 per million population. The mean age of the prevalent dialysis patients in the patient survey was 69.09 years. Diabetic nephropathy was the most common primary disease of the prevalent dialysis patients (39.1%), followed by chronic glomerulonephritis (25.7%) and nephrosclerosis (11.4%). The number of incident dialysis patients during 2019 was 40,885; it increased by 417 from 2018. The average age was 70.42 years and diabetic nephropathy (41.6%) was the most common cause in incident dialysis patients. Nephrosclerosis became the second cause followed by glomerulonephritis. As 34,642 patients died in 2019, the crude annual mortality rate was 10.1%. The three major causes of death were heart failure (22.7%), infectious disease (21.5%) and malignancy (8.7%). The patients treated by hemodiafiltration (HDF) have been increasing in number rapidly since 2012. The number has reached 144,686 by the end of 2019, which accounted for 42.0% of all dialysis patients. The number of peritoneal dialysis (PD) patients was 9,920 in 2019, which has slightly increased since 2017. The combination or hybrid therapy with hemodialysis (HD) or HDF was given to 19.2% of PD patients. Home HD therapy was conducted in 760 patients at the end of 2019; it increased by 40 from 2018. It was 10 years since the previous survey in 2009 that the present status of CKD-MBD treatment was comprehensively surveyed in 2019. Clinical efficacy of newly introduced medicines during this period and the influence of the CKD-MBD guidelines revised in 2012 should be further analyzed. These analyses would be the basis for the next revision of the CKD-MBD guidelines, and it could provide deeper therapeutic insights for CKD-MBD.

[Background] Ultrasonography is useful in vascular access (VA) surveillance. However, there are no criteria to predict the appropriate timing of intervention. AI technology has been advancing rapidly in recent years. Its application in the medical field has also been progressing. In this study, we aimed to predict the appropriate timing of VA intervention therapy using machine learning with Python. [Method] We targeted 1862 patients who underwent ultrasonography. All the data were learned and predicted using machine learning. We examined the accuracy of the obtained data after the area under the curve (AUC) was calculated from the receiver operating characteristic (ROC) curve of each algorithm. We compared the rates of accuracy between the machine learning algorithms and the criteria of guidelines. [Results] We determined that the best algorithm was logistic regression, given that it yielded the following values: AUC (0.88), sensitivity (0.85), specificity (0.71), and accuracy rate (0.83). The guidelines yielded the following values: sensitivity (0.69), specificity (0.86), and accuracy rate (0.72). [Conclusion] Machine learning predictions exceeded the Guideline accuracy score. These results suggest that machine learning may be used to predict the appropriate timing of VA treatment.

[Objectives] The aim of this study was to evaluate graft patency and analyze factors related to graft survival and the effects of VAIVT (Vascular access intervention therapy) and surgical revisions. [Methods] Between January 2002 and March 2016, 540 polyurethane vascular access grafts (THORATEC^®) were performed at our hospital. We calculated the cumulative patency rates of these grafts, including the primary patency (problem-free), VAIVT-assisted primary patency (surgical revision-free), and secondary patency (functional) by the Kaplan-Meier method. Secondly, all grafts were classified into the following three groups according to the annual average of PTA times: 215 cases in the PTA-untreated group, 163 cases in the lower frequency group, and 162 cases in the higher frequency group. We analyzed the relationship between the PTA times and cumulative patency, and we examined factors related to graft survival by the COX proportional hazard model. [Results] Primary patency of all grafts was 35.7% at 1 year, 20.0% at 2 years and 7.5% at 5 years. VAIVT-assisted primary patency was 78.8% at 1 year, 70.4% at 2 years and 55.7% at 5 years. Secondary patency was 92.6% at 1 year, 86.0% at 2 years and 74.3% at 5 years. Among the three groups classified according the annual average PTA times, the lower frequency group showed significantly better results than the higher frequency group for secondary patency and VAIVT-assisted primary patency. On multivariate analysis, a larger diameter of the anastomotic vein was significantly correlated with a better secondary patency rate. [Conclusions] The results of graft patency varied according to the conditions. The development of more appropriate methods to obtain and manage a polyurethane vascular access graft is expected in the future.

A 61-year-old woman was transferred to our hospital with nausea, tense abdominal distension, and upper abdominal pain. She exhibited bilateral cyanosis and livedo reticularis of both lower extremities. Contrast-enhanced computed tomography revealed that the markedly expanded stomach compressed the abdominal aorta, resulting in a lack of contrast enhancement of the aorta distal to the renal arteries. We diagnosed the patient with gastric volvulus causing abdominal aortic compression, and inserted a stomach tube in order to decompress the stomach. Although the cyanosis and livedo reticularis immediately resolved, she developed hypotension and disturbance of consciousness and required mechanical ventilation. She showed port-wine-colored urine, and arterial blood gas analysis showed lactic acidosis and hyperkalemia. We diagnosed her with myonephropathic metabolic syndrome (MNMS) caused by ischemia-reperfusion injury resulting from the release of aortic compression following gastric decompression, and urgently initiated blood purification therapy. For the ischemic stomach, total gastrectomy was performed after her general condition improved. We discontinued renal replacement therapy about one month later, as her kidney function recovered. In cases of MNMS with extensive ischemia-reperfusion, it is necessary to consider urgent blood purification therapy.