Cellular and humoral immune responses to COVID-19 booster vaccination in Japanese dialysis patients.

BACKGROUND: Dialysis patients are susceptible to developing severe coronavirus disease 2019 (COVID-19) due to hypoimmunity. Antibody titers against severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) after the primary vaccinations are lower in hemodialysis (HD) patients than in healthy individuals. This study aimed to evaluate the effect of a SARS-CoV-2 booster vaccination in HD and peritoneal dialysis (PD) patients based on antibody titers and cellular and humoral immunity. METHODS: Participants of the control, HD, and PD groups were recruited from 12 facilities. SARS-CoV-2 antigen-specific cytokine and IgG-antibody levels were measured. Regulatory T cells and memory B cells were counted using flow cytometry at 6 months after primary vaccination with BNT162b2 and 3 weeks after the booster vaccination in HD and PD patients and compared with those of a control group. RESULTS: Booster vaccination significantly enhanced the levels of antibodies, cytokines, and memory B cells in three groups. The HD group showed significantly higher levels of IgG-antibodies, IL-1ß, IL-2, IL-4, IL-17, and memory B cells than those in the control group at 3 weeks after the booster dose. The PD group tended to show similar trends to HD patients but had similar levels of IgG-antibodies, cytokines, and memory B cells to the control group. CONCLUSIONS: HD patients had significantly stronger cellular and humoral immune responses than the control 3 weeks after the booster dose. Our findings will help in developing better COVID-19 vaccination strategies for HD and PD patients.

Changes in spike protein antibody titer over 90 days after the second dose of SARS-CoV-2 vaccine in Japanese dialysis patients.

OBJECTIVES: There is no report on antibody titers after vaccination against SARS-CoV-2 in Japanese dialysis patients. As dialysis is different between Japan and other countries, changes in antibody titers were examined. METHODS: Baseline characteristics and anti-spike protein antibody titers (Roche) over 90 days after administration of the BNT162b2 messenger RNA vaccine were investigated in dialysis patients. RESULTS: The maximum anti-spike protein antibody titer after the second dose was 738 (327 to 1143) U/mL and was reached at 19 (17 to 24) days after the second dose. Antibody titers decreased over time, with titers of 770 (316 to 1089) U/mL at 15 days, 385 (203 to 690) U/mL at 30 days, 254 (138 to 423) U/mL at 60 days, and 208 (107 to 375) U/mL at 90 days after the second dose. When an antibody titer of 137 U/mL was assumed to be a measure related to breakthrough infection, the proportion of subjects with antibody titers exceeding this level was 90.1% at 15 days, 85.3% at 30 days, 75.0% at 60 days, and 65.4% at 90 days after the second dose. When a decrease in antibody titers below the assumed breakthrough level was defined as an event, subjects with a pre-dialysis albumin ≥ 3.5 g/dL were significantly less likely to experience an event than subjects with a pre-dialysis albumin < 3.5 g/dL. CONCLUSIONS: The presence of anti-spike protein levels ≥ 313 U/mL at 30 days after the second vaccine dose might be a factor in maintaining enough antibody titers at 90 days after. Whether an additional vaccine dose is needed should be determined based on indicators serving as factors in maintaining antibody titers as well as the status of the spread of infection.

Retraction Note: Impact of the third wave of the COVID-19 pandemic and interventions to contain the virus on society and patients with kidney disease in Cambodia.

[This retracts the article DOI: 10.1186/s41100-021-00372-6.].

Impact of the third wave of the COVID-19 pandemic and interventions to contain the virus on society and patients with kidney disease in Cambodia.

Cambodia detected its first case of COVID-19 just 3 days before WHO declared that the outbreak constituted as PHEIC. As of February 15, 2021, and after two major outbreaks, only 479 cases had been reported, 396 (83%) of which were imported. This small number of cases was largely thanks to stringent measures and policies put in place by the government to curb the spread. Despite these efforts, a third cluster outbreak was declared on February 20, 2021. It has disrupted all aspects of life in Cambodia. As in many other countries affected by the virus, economic hardship, lockdowns in cities, and food insecurity ensued. Against the backdrop of this widespread impact on the citizens of Cambodia, we conducted this review article to better understand the situation of healthcare workers in nephrology and dialysis patients and the challenge they face in providing and receiving essential medical care. Healthcare providers have continued working to serve their patients despite facing a high risk of catching SARS-CoV-2 and other challenges including difficulties in traveling to work, increased physical and mental burden, and higher stress due to measures taken to minimize the risk of transmission during patients' care. Some healthcare workers have been discriminated against by neighbors. The most difficult mission is when having to deal with families whose loved one is denied access to a hemodialysis session due to suspected COVID-19 while waiting for PCR test results. Hemodialysis patients reported facing economic hardship and increasingly difficult circumstances. When access to food is limited, patients have eaten canned or dried salted food rather than an appropriate hemodialysis diet. Because hemodialysis centers are concentrated in a few cities, access has become even harder during the travel ban. In-center hemodialysis rules are stricter and does not allow family members or escorts to enter the unit. Only a few hemodialysis patients have been vaccinated. Before COVID-19, hemodialysis patients already faced major burdens. The pandemic appears to be decreasing their quality of life and survival even further. Through this study, we have revealed current hardships and the need to improve the situations for both healthcare workers in nephrology and hemodialysis patients in Cambodia.

Support for Dialysis Therapy in Vietnam, Cambodia, and Myanmar by Japanese Societies in the Field of Blood Purification.

With recent economic development in Southeast Asia, there have been improvements in medical services and healthcare provision. This has led to increased numbers of dialysis patients and increased numbers of dialysis facilities in the region. To assist economically developing countries in managing this change, support projects from Japan have been conducted in the region since around 2007. This article summarizes and discusses Japan's support activities, in which some of the authors were directly involved, in Vietnam, Cambodia, and Myanmar. Initial support was mainly organized by the non-governmental organization Ubiquitous Blood Purification International (NGO UBPI), and currently several organizations in the field of blood purification work together to offer ongoing support in the region. Many positive changes have resulted from these activities in Southeast Asia, but challenges remaining for the future are to establish an educational system for each dialysis specialty and develop dialysis techniques ensuring high treatment quality and safety.

Japan's Support of Hemodialysis in Southeast Asia.

BACKGROUND: With continuing economic development in the developing countries of Southeast Asia, the numbers of dialysis facilities and patients are increasing every year. However, dialysis-related devices tend to be provided with financial support from developed countries and/or donations from nonprofit organizations, and some donated devices are disposed of, without attempts at repair, when they break down. Device management and dialysate quality can also be problematic. SUMMARY: To help address these issues, Japan started to provide technical guidance and support for dialysate purification in these countries. As a result, dialysate quality improved and local medical staff can now perform dialysis therapy using purified dialysate. At the same time, education was provided to staff, and their improved knowledge and skills have contributed to appropriate device maintenance, ensuring the dialysate used is of sufficient quality. Currently, approaches for human resource development are being actively provided in these countries through cooperation with local academic societies or other organizations in the field. Key Messages: A review of the current status of management of dialysis-related devices and dialysate quality in developing countries reveals that financial support and donations for medical devices alone are insufficient and the development of local human resources is crucial. Nurturing and training of clinical engineers, who directly operate today's advanced medical devices for patients, as well as device maintenance and management are urgent issues to address.

Increase in the dosage amount of vitamin D3 preparations by switching from calcium carbonate to lanthanum carbonate.

It is widely known that dialysis patients who are administered vitamin D preparations have a better prognosis than patients who are not. In this study, of 22 patients on maintenance dialysis who had been administered calcium (Ca) carbonate in our hospital, we investigated the dosage amount of vitamin D3 preparations after the phosphorus (P) binder was switched from Ca carbonate to the newly developed lanthanum carbonate (LC). After completely switching to LC, the dosage amount of oral vitamin D3 preparation (alfacalcidol equivalent) was significantly increased from 0.094 µg/day to 0.375 µg/day (P = 0.0090). No significant changes were observed in the values of serum corrected Ca, alkaline phosphatase, intact parathyroid hormone and P after switching. The administration of LC enabled complete cessation of the administration of Ca carbonate preparations, and increased the dosage amount of vitamin D3 preparations. Therefore, LC may be a useful P binder to improve patient prognosis.

Dialysis and quality of dialysate in southeast asian developing countries.

BACKGROUND: The number of dialysis patients has been increasing in Southeast Asia, but statistical data about these patients and on the quality of dialysates in Southeast Asian dialysis facilities are still imprecise. For this study, dialysis-related statistical data were collected in Southeast Asia. METHODS: A survey of the quality of dialysates was carried out at 4 dialysis facilities in Vietnam and Cambodia. The dialysis patient survey included the numbers of dialysis facilities and patients receiving dialysis, a ranking of underlying diseases causing the initiation of dialysis, the number of patients receiving hemodialysis (HD)/on-line hemodiafiltration/continuous ambulatory peritoneal dialysis, the number of HD monitoring devices installed, the cost of each session of dialysis (in USD), the percentage of out-of-pocket payments, and the 1-year survival rates of the dialysis patients (in percent). The dialysate survey covered the endotoxin (ET) level and bacterial count in tap water, in water filtered through a reverse osmosis system and in dialysate. RESULTS: In each of the countries, the most frequent reason for the initiation of dialysis is diabetes mellitus. HD is usually carried out according to the 'reuse' principle. The 1-year survival rates are 70% in Myanmar and about 90% in the Philippines and Malaysia. The ET levels in standard dialysates were satisfactory at 2 facilities. The bacterial counts in dialysates were not acceptable at any of the facilities investigated. CONCLUSION: There is an urgent need to teach medical workers involved in dialysis how to prepare sterile and ET-free dialysates.

[Irradiation for invasive malignant thymoma led a remission of refractory minimal change nephrotic syndrome: a case report].

A 46-year-old man was diagnosed as malignant thymoma, and was treated with chemotherapy and radiotherapy in 2003. On June 2004, he had edema of his legs and nephrotic syndrome (NS). As renal biopsy revealed a minor glomerular abnormality, he was diagnosed as minimal change nephrotic syndrome (MCNS). Intravenous steroid therapy of 500 mg/day for 3 days, following oral administration of 15 mg/day prednisolone and 75 mg cyclosporine twice a day was taken from July 2004. On July 2005, he went into remission of NS with 0.6 g/day proteinuria. On January 2008, NS relapsed with left pleural effusion. Chest CT and a biopsy specimen from left pleural mass lesion revealed the pleural invasion of malignant thymoma. Sixty Gray radiotherapy diminished the pleural metastatic lesion and also improved proteinuria from 6.6 g/day to 0.4 g/day. Though there have been a few case reports of MCNS concomitant with malignant thymoma, this is the first report that radiotherapy for metastatic malignant thymoma improved NS while diminishing the tumor.

[Treatment of adynamic bone disease with the complete replacement from calcium carbonate to sevelamer hydrochloride].

The aim of this study was to examine the therapeutic effect of hypocalcemic stimulation caused by sevelamer hydrochloride (SH) administration on adynamic bone disease (ABD). The subjects were 28 maintenance hemodialysis (HD) patients who had remained in ABD state in spite of no administration of vitamin D(3) since HD induction (15 males and 13 females;12 diabetic patients and 16 non-diabetic patients). The mean age was 61.8+/-9.5 years and the mean HD duration was 5.5+/-3.9 years. The calcium concentration in the dialysate was 3.0 mEq/L. We made the final daily dose of SH after two months the same as the first daily dose of calcium carbonate (CC) in the following manner. At first we administered only CC at breakfast and lunch and SH at supper. And for the next two weeks we administered CC at breakfast and SH at lunch and supper. And for the final two weeks we administered only SH. After that we increased the dose of SH as much as possible. We evaluated the therapeutic effect of the above treatment on ABD using intact-osteocalcin (iOC) [Teijin. Tokyo] as a marker before and 6, 12 months after the beginning of the replacement. If iOC Ievel of 30 to 70 ng/mL showed normal tumover bone (NTB), 5 cases (17.9%) changed into NTB in 6 months. 9 cases (32.1%) changed into NTB in 12 months and one case (3.6%) changed into ostitis fibrosa in 12 months. It is thought that SH is effective for the treatment of ABD but we have to be careful for ostitis fibrosa.

[Sevelamer:hydrochloride].

The recent global breakthrough in the field of renal osteodystrophy is the inhibitory effect of sevelamer hydrochloride on the progression of coronary artery calcification, which was revealed with EBCT (Electron beam computed tomography) 1) approximately 3). It has been found that the degree of coronary artery calcification assessed with EBCT is proportional to the mortality risk by the coronary artery stenosis and by myocardial infarction in non-hemodialysis patients 4) approximately 10). In 2004 in Japan Matsuoka and Iseki et al showed for the first time in the world that coronary artery calcification assessed by EBCT was correlated with mortality 11). In Japan, however, it is difficult to administer sevelamer hydrochloride to many patients because of constipation as its side effect. Its prescription rate is 26.8% and its single administration rate is only 15.4% 12). We explained fully to the patients that sevelamer hydrochloride seldom caused coronary artery calcification. And we used sorbitol, an osmotic purgatives, with sevelamer hydrochloride. Moreover, we gradually replaced calcium carbonate with sevelamer hydrochloride in supper at first. With protocol above, we succeeded in having 86.7% of the patients take sevelamer hydrochloride 12). We think that it is important to increase the intake rate of sevelamer hydrochloride in order to prevent coronary artery calcification and to aim at the long survival of the patients.