Managing Interhospital Referrals During a COVID-19 Patient Surge in Japan: Creating Available Beds by Exchanging Patients.

A COVID-19 patient surge in Japan from July to September 2021 caused a mismatch between patient severity and bed types because hospital beds were fully occupied and patient referrals between hospitals stagnated. Japan's predominantly private healthcare system lacks effective mechanisms to coordinate healthcare providers to address the mismatch. To address the surge, in August 2021, Tokyo Saiseikai Central Hospital started a scheme to exchange patients with other hospitals to mitigate the mismatch. In this article, we outline a retrospective observational study using medical records from a tertiary care medical center that treated severe COVID-19 cases. We describe daily patient admissions to our hospital's COVID-19 beds from July to September 2021, and compared the moving average of daily admissions before and after the exchange scheme was introduced. Bed occupancy reached nearly 100% in late July when the patient surge began and continued to exceed 100% in August when the surge peaked. However, the average daily admission did not decrease in August compared with July: the median daily admission (25th to 75th percentile) during each period was 2 (1 to 2.5) in late July and 3 (2 to 4) in August. The number of patients referred in from secondary care hospitals and the number of patients referred out was balanced in August. During the patient surge, the exchange scheme enabled the hospital to maintain and even increase the number of new admissions despite the bed shortage. Coordinating patient referrals in both directions simultaneously, rather than the usual 1-way transfer, can mitigate such mismatches.

T-Cell Response and Antibody Production Induced by the COVID-19 Booster Vaccine in Japanese Chronic Kidney Disease Patients Treated with Hemodialysis.

Humoral and cellular responses are critical in understanding immune responses to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination. Here, we evaluated these responses in hemodialysis (HD) patients after the booster vaccination. SARS-CoV-2 immunoglobulin (IgG) levels, neutralizing antibody titers, and the T-SPOT®.COVID test (T-SPOT) were measured prior to, three weeks after, and three months after the booster administration. The HD group had significantly higher SARS-CoV-2 IgG levels and neutralizing antibody titers against the original strain at three weeks and three months after the booster vaccination compared to the control group, albeit the HD group had lower SARS-CoV-2 IgG levels and neutralizing antibody titers before the booster administration. Moreover, the HD group had significantly higher T-SPOT levels at all three time points compared to the control group. The HD group also had significantly higher local and systemic adverse reaction rates than the control group. By booster vaccination, HD patients could acquire more effective SARS-CoV-2-specific humoral and cellular immunity than the control group.

Estimating immunity with mathematical models for SARS-CoV-2 after COVID-19 vaccination.

Tools that can be used to estimate antibody waning following COVID-19 vaccinations can facilitate an understanding of the current immune status of the population. In this study, a two-compartment-based mathematical model is formulated to describe the dynamics of the anti-SARS-CoV-2 antibody in healthy adults using serially measured waning antibody concentration data obtained in a prospective cohort study of 673 healthcare providers vaccinated with two doses of BNT162b2 vaccine. The datasets of 165 healthcare providers and 292 elderly patients with or without hemodialysis were used for external validation. Internal validation of the model demonstrated 97.0% accuracy, and external validation of the datasets of healthcare workers, hemodialysis patients, and nondialysis patients demonstrated 98.2%, 83.3%, and 83.8% accuracy, respectively. The internal and external validations demonstrated that this model also fits the data of various populations with or without underlying illnesses. Furthermore, using this model, we developed a smart device application that can rapidly calculate the timing of negative seroconversion.

Effectiveness of SARS-CoV-2 vaccines on hemodialysis patients in Japan: A nationwide cohort study.

INTRODUCTION: This study compared the outcomes of dialysis patients who received SARS-CoV-2 vaccine with those who did not use data from the Japanese COVID-19 registry. METHODS: A total of 1260 dialysis patients with confirmed positive SARS-CoV-2 infection was included in this study. Patients were divided into two groups: patients who experienced breakthrough infection and those who were unvaccinated. The need of oxygen supplementation and mortality risks were compared using multivariate logistic regression analysis. RESULTS: The mortality rate was 24.2% in unvaccinated patients and 8.6% in breakthrough patients. The odds ratio of need of oxygen supplementation in the breakthrough patients relative to unvaccinated patients was 0.197. The hazard ratio of mortality in the breakthrough patients relative to unvaccinated patients was 0.464. CONCLUSION: Our prospective observational study showed that SRAS-CoV-2 vaccination in hemodialysis patients is vital for reducing need of oxygen supplementation and mortality risk.

腹膜透析と新型コロナウイルス感染症

新型コロナウイルス感染症（COVID‒19）は2022 年4 月現在，依然として猛威を振るっている．透析患者は重症化のリスクが高く，死亡率も8.8％と一般人口の0.38％と比較して非常に高い．腹膜透析患者も死亡率は9.5％と高い．パンデミックの初期には腹膜透析患者は血液透析患者と比べて罹患率が低く，死亡率も低いことが報告されていたが，日本からの報告では有意差は認めていない．しかし，透析患者は重症化しやすいことには変わりなく，早期診断，早期治療が求められる．抗ウイルス薬や抗炎症薬は透析患者の予後改善に役立つが，腎機能低下の患者では，使用に注意するべき点があり，薬剤の特徴をよく理解した上で使用する必要がある．また，COVID‒19 に罹患しても基本的には腹膜透析を継続することは可能であるが，患者が重症化した場合には，体液量の調節および腹臥位療法の観点から持続的血液濾過透析を考慮することもある．腹膜透析を施行した場合には，排液は感染性があることに留意する．今回われわれが経験したパンデミックは在宅医療の重要性を再認識させられた．患者が腎代替療法を選択する際には，医療従事者は，パンデミックや災害時の観点からの説明も重要である．また，われわれもパンデミックの際に慌てないように遠隔患者管理プログラムなどの情報通信技術を用いて医療体制の構築が求められる．

Investigation for the efficacy of COVID-19 vaccine in Japanese CKD patients treated with hemodialysis

Background Dialysis patients are predisposed to severe disease and have a high mortality rate in coronavirus disease 2019 (COVID-19) due to their comorbidities and immunocompromised conditions. Therefore, dialysis patients should be prioritized for vaccination. This study aimed to examine how long the effects of the vaccine are maintained and what factors affect antibody titers. Methods Hemodialysis patients (HD group) and age- and sex-matched non-dialysis individuals (Control group), receiving two doses of BNT162b2 vaccine, were recruited through the Japanese Society for Dialysis Therapy (JSDT) Web site in July 2021. Anti-SARS-CoV-2 immunoglobulin (IgG) (SARS-CoV-2 IgG titers) was measured before vaccination, 3 weeks after the first vaccination, 2 weeks after the second vaccination, and 3 months after the second vaccination, and was compared between Control group and HD group. Factors affecting SARS-CoV-2 IgG titers were also examined using multivariable regression analysis and stepwise regression analysis (least AIC). In addition, we compared adverse reactions in Control and HD groups and examined the relationship between adverse reactions and SARS-CoV-2 IgG titers. Results Our study enrolled 123 participants in the Control group (62.6% men, median age 67.0 years) and 206 patients in the HD group (64.1% men, median age 66.4 years). HD group had significantly lower SARS-CoV-2 IgG titers at 3 weeks after the first vaccination (p < 0.0001), 2 weeks after second vaccination (p = 0.0002), and 3 months after the second vaccination (p = 0.045) than Control group. However, the reduction rate of SARS-CoV-2 IgG titers between 2 weeks and 3 months after the second vaccination was significantly smaller in HD group than in Control (p = 0.048). Stepwise regression analysis revealed that dialysis time was identified as the significant independent factors for SARS-CoV-2 IgG titers at 2 weeks after the second vaccination in HD group (p = 0.002) and longer dialysis time resulted in higher maximum antibody titers. The incidences of fever and nausea after the second vaccination were significantly higher in the HD group (p = 0.039 and p = 0.020). Antibody titers in those with fever were significantly higher than those without fever in both groups (HD: p = 0.0383, Control: p = 0.0096). Conclusion HD patients had significantly lower antibody titers than age- and sex-matched non-dialysis individuals over 3 months after vaccination. Dialysis time was identified as a factor affecting SARS-CoV-2 IgG titers in HD group, with longer dialysis time resulting in higher maximum SARS-CoV-2 IgG titers.

Patients with hemodialysis-induced hypoxemia had a poor prognosis of COVID-19.

Background: We experienced that some hemodialysis (HD) patients with coronavirus disease 2019 (COVID-19) exacerbated hypoxemia during HD. Though HD-induced hypoxemia has been reported, there have been no reports of HD-induced hypoxemia in patients with COVID-19 and its effect on prognosis of COVID-19. Methods: Eleven HD patients admitted with COVID-19 from August 2020 to April 2021 were classified into the patients whose oxygen demand increased by more than 3 L/min with mask during HD (worsened group, n = 5) and others (not-worsened group, n = 6). The background, laboratory findings, severity of COVID-19 and prognosis were compared between the two groups. In addition, blood gases were measured before and after dialysis among HD patients admitted with COVID-19 on April 2021 (n = 3). Results: There were no significant differences in backgrounds, except for a higher proportion of diabetes mellitus in worsened group (p = 0.04). Although laboratory findings were not significantly different on admission day, albumin and LDH levels 7 days after admission were significantly lower and higher in worsened group, respectively (p = 0.03 and < 0.01). The severity of COVID-19 and survival rate were significantly worse in worsened group (p = 0.01 and 0.03). The alveolar-arterial oxygen pressure difference (Aa-DO2) opened during HD in a patient with HD-induced hypoxemia, but did not open in patients without HD-induced hypoxemia. Conclusions: There is a close relationship among HD-induced hypoxemia and poor prognosis of COVID-19. The HD-induced hypoxemia of patients with COVID-19 may be caused by ventilation/perfusion mismatching. Supplementary Information: The online version contains supplementary material available at 10.1186/s41100-022-00408-5.

A case of Bacillus subtilis var. natto bacteremia caused by ingestion of natto during COVID-19 treatment in a maintenance hemodialysis patient with multiple myeloma.

A 70-year-old woman, who started on hemodialysis 7 months before for end-stage renal disease due to diabetic nephropathy and was diagnosed with symptomatic multiple myeloma 1 month before, was admitted to our hospital with critical coronavirus disease 2019 and treated with long-term immunosuppressive therapy such as steroids and tocilizumab. During treatment, Bacillus subtilis was detected in the blood cultures. We could not exclude the association of natto (fermented soybeans) with B. subtilis var. natto, which the patient had been eating every day from 8 days after admission. She was prohibited from eating natto and treated with vancomycin. Later, B. subtilis detected in the blood culture was identified as B. subtilis var. natto, which was identical with those contained in the natto that the patient consumed daily using a next-generation sequencer. Gut dysbiosis due to old age, malignant tumor, diabetes mellitus, end-stage renal disease, and intestinal inflammation caused by severe acute respiratory syndrome coronavirus 2 increased intestinal permeability and the risk of bacterial translocation, causing B. subtilis var. natto bacteremia. Therefore, careful consideration might be given to the intake of fermented foods containing live bacteria in patients with severe immunocompromised conditions.

Survival and predictive factors in dialysis patients with COVID-19 in Japan: a nationwide cohort study.

BACKGROUND: The Japanese Association of Dialysis Physicians, the Japanese Society for Dialysis Therapy, and the Japanese Society of Nephrology jointly established COVID-19 Task Force Committee and began surveying the number of newly infected patients. METHODS: This registry of the COVID-19 Task Force Committee was used to collect data of dialysis patients; a total of 1010 dialysis patients with COVID-19 were included in the analysis. Overall survival of patients was investigated with stratification by age group, complication status, and treatment. In addition, predictive factors for mortality were also investigated. The overall survival was estimated by Kaplan-Meier methods and compared by using log-rank test. Multivariate analysis was performed to identify the risk factor of mortality. For all statistical analyses, p < 0.05 was considered to be statistically significant. RESULTS: The mortality risk was increased with age (p < 0.001). The mortality risk was significantly higher in patients with peripheral arterial disease (HR: 1.49, 95% CI 1.05-2.10) and significantly lower in patients who were treated with remdesivir (HR: 0.60, 95% CI 0.37-0.98). Multivariate analysis showed increased risk of mortality with increment in BMI, and increment in CRP, and decreased risk with increment in albumin. CONCLUSION: Dialysis patients have a high severity of illness and a high risk of mortality in cases of COVID-19. Treatment with remdesivir might be effective in shortening the duration of hospitalization and reducing the risk of mortality.

Committee report: Questionnaire survey on the treatment of COVID-19 in patients receiving dialysis therapy.

Background: Patients with coronavirus disease 2019 (COVID-19) who receive dialysis therapy develop more severe disease and have a poorer prognosis than patients who do not. Although various data on the treatment of patients not receiving dialysis therapy have been reported, clinical practice for patients on dialysis is challenging as data is limited. The Infection Control Committee of the Japanese Society for Dialysis Therapy decided to clarify the status of treatment in COVID-19 patients on dialysis. Methods: A questionnaire survey of 105 centers that had treated at least five COVID-19 patients on dialysis was conducted in August 2021. Results: Sixty-six centers (62.9%) responded to the questionnaire. Antivirals were administered in 27.7% of facilities treating mild disease (most patients received favipiravir) and 66.7% of facilities treating moderate disease (most patients with moderate or more severe conditions received remdesivir). Whether and how remdesivir is administered varies between centers. Steroids were initiated most frequently in moderate II disease (50.8%), while 43.1% of the facilities initiated steroids in mild or moderate I disease. The type of steroid, dose, and the duration of administration were generally consistent, with most facilities administering dexamethasone 6 mg orally or 6.6 mg intravenously for 10 days. Steroid pulse therapy was administered in 48.5% of the facilities, and tocilizumab was administered in 25.8% of the facilities, mainly to patients on ventilators or equivalent medications, or to the cases of exacerbations. Furthermore, some facilities used a polymethylmethacrylate membrane during dialysis, nafamostat as an anticoagulant, and continuous hemodiafiltration in severe cases. There was limited experience of polymyxin B-immobilized fiber column-direct hemoperfusion and extracorporeal membrane oxygenation. The discharge criteria for patients receiving dialysis therapy were longer than those set by the Ministry of Health, Labor and Welfare in 22.7% of the facilities. Conclusions: Our survey revealed a variety of treatment practices in each facility. Further evidence and innovations are required to improve the prognosis of patients with COVID-19 receiving dialysis therapy.

Factors associated with SARS-CoV-2 antibody titers and prognosis of breakthrough infection in hemodialysis patients.

BACKGROUND: The mortality rate of Coronavirus disease 2019 (COVID-19) is extremely high in hemodialysis patients (HDP). These patients also develop lower antibody titers after vaccination. Therefore, factors associated with antibody titers and vaccine efficacy in HDP with breakthrough infection need to be investigated. METHODS: We measured anti-S1 antibody titers in HDP (n = 104) and controls (n = 35), evaluating the influence of background on HDP by multivariable regression analysis. We classified 26 HDP patients admitted with COVID-19 into the unvaccinated (n = 15) and breakthrough infection group (n = 11), performing between-group comparisons of laboratory findings and prognosis. Vaccinated COVID-19 patients were classified into HDP and non-HDP controls, and compared the relationship between antibody titer and severity, and the prognosis of breakthrough infection. RESULTS: The antibody titer was significantly lower in the HDP group than in the control group. Among HDP, age and smoking history were significantly independent factors associated with antibody titer. The breakthrough infection group had significantly better laboratory findings (KL-6 and LDH), severity, and hospitalization period than the unvaccinated group even if antibody titers were lower than the known threshold for neutralization (p < 0.05). There was no significant difference in prognosis between the HDP and non-HDP with breakthrough infection. Severity of COVID-19 tended to be higher with lower antibody titer in non-HDP, but not in HDP. CONCLUSION: Vaccines improved the severity of COVID-19 and hospitalization period of breakthrough infection in HDP, although HDP, especially in elderly smokers had lower antibody titers than control. There was no significant association between antibody titer and severity in HDP.

COVID-19 vaccine induced interstitial lung disease.

A 60-year-old man presented with dyspnea four days after the second dose of the coronavirus disease (COVID-19) vaccine. Imaging revealed extensive ground-glass opacification. Blood tests were notable for elevated KL-6 levels. Bronchoalveolar lavage fluid analysis showed increased lymphocyte-dominant inflammatory cells and decreased CD4/CD8 ratio. These findings were consistent with the diagnosis of drug-induced interstitial lung disease (DIILD). To the best of our knowledge, this has never been reported in previous literature. Treatment with glucocorticoids relieved his symptoms. This paper highlights that although extremely rare, COVID-19 vaccine could cause DIILD, and early diagnosis and treatment are crucial to improve patient outcomes.

Clinical efficacy and safety of combination therapy of tocilizumab and steroid pulse therapy for critical COVID-19 in HD patients.

BACKGROUND: Critical coronavirus disease 2019 (COVID-19) has a high fatality rate, especially in hemodialysis (HD) patients, with this poor prognosis being caused by systemic hyperinflammation; cytokine storms. Steroid pulse therapy or tocilizumab (TCZ) have insufficient inhibitory effects against cytokine storms in critical cases. This study evaluated the clinical effects and safety of combining steroid pulse therapy and TCZ. METHODS: From September 2020 to May 2021, 201 patients with COVID-19 were admitted to our hospital. Before February 2021, patients with an oxygen demand exceeding 8 L/min were intubated and treated with standard therapy (dexamethasone and antiviral therapy). After February 2021, patients underwent high-flow nasal cannula oxygen therapy and were treated with TCZ (8 mg/kg) and methylprednisolone (mPSL) (500 mg/day [≤ 75 kg], 1000 mg/day [> 75 kg]) for 3 days. We compared background characteristics, laboratory findings, and prognosis between non-HD and HD patients and between patients who received and did not receive TCZ and mPSL pulse therapy. RESULTS: Among non-HD patients, the TCZ + mPSL pulse group had significantly higher survival rates and lower secondary infection rates (p < 0.05), than the standard therapy group. All HD patients in the standard therapy group with oxygen demand exceeding 8 L/min died. Contrastingly, all patients in the TCZ + mPSL pulse group survived, with their oxygen demand decreasing to 0-1 L/min within 3 weeks post-administration. CONCLUSION: TCZ combined with mPSL pulse therapy improved the survival rate without significant adverse events in critical HD and non-HD patients with COVID-19 by strongly suppressing systemic hyperinflammation.

Nationwide survey of the coronavirus disease 2019 prevention and treatment systems for kidney disease patients: a study of Japanese Society of Nephrology-certified educational facilities.

BACKGROUND: There are no reports of a large-scale survey on the infection prevention measures against coronavirus disease 2019 (COVID-19) in nephrology facilities. This study investigated the facility-level nephrology practices adopted during the COVID-19 pandemic and their associated challenges. Additionally, the treatment patterns and outcomes of chronic kidney disease (CKD) patients with COVID-19 were reviewed. METHODS: We conducted a nationwide questionnaire survey of 704 educational facilities that were certified by the Japanese Society of Nephrology (JSN) from October 20, 2020 to November 16, 2020. The questionnaire reviewed the facility characteristics, infection prevention measures taken during routine nephrology practice, impact of COVID-19 on nephrology practice, experiences in managing CKD patients with COVID-19, and nosocomial transmission in the nephrology unit. RESULTS: Of the 347 facilities that responded, 95.1% checked outpatients' body temperatures and COVID-19 symptoms at their visits. To reduce face-to-face contact, 80% and 70% of the facilities lengthened the intervals between outpatient visits and introduced online/telephonic consultations, respectively. As a result, more than half of the hospitals experienced a decrease in the numbers of outpatients and inpatients (64% and 50%, respectively). During the study period, 347 facilities managed 479 CKD patients with COVID-19. Oxygen administration and mechanical ventilation were performed for 47.8% and 16.5% of the patients, respectively, with a 9.2% total mortality rate. CONCLUSION: This survey demonstrated that JSN-certified educational nephrology facilities adopted multiple measures to manage the COVID-19 pandemic; however, they faced several challenges. Sharing these experiences could standardize these approaches and prepare us better for the future.

Infection prevention measures for patients undergoing hemodialysis during the COVID-19 pandemic in Japan: a nationwide questionnaire survey.

BACKGROUND: Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has become a global pandemic affecting a variety of medical treatments, including hemodialysis. This study aims to investigate the implementation of infection control measures, to examine the shortage of personal protective equipment (PPE) and disinfectants, and to quantify the number of nosocomial COVID-19 transmissions in hemodialysis facilities in Japan during the pandemic. METHODS: We conducted a nationwide questionnaire survey between 20 October and 16 November 2020 (i.e., between the "second wave" and "third wave" in Japan) in the 4198 dialysis facilities of the Japanese Association of Dialysis Physicians and the Japanese Society for Dialysis Therapy. A total of 2227 facilities (53.0%) responded. The questionnaire consisted of (i) characteristics of facilities, (ii) infection prevention measures in routine dialysis practices, (iii) shortage of PPE, (iv) feasibility of various isolation measures, and (v) nosocomial transmission. RESULTS: Half of the responding facilities were hospitals with multiple departments, and the other half were clinics specialized in dialysis. Several infection prevention measures such as health checks of staff and patients, donning of masks before and after hemodialysis, and disinfection of frequently contacted areas were implemented during the COVID-19 pandemic. There was a significant improvement in the implementation rate of these measures during the pandemic, compared to before it, which reached over 90%. More than half of the facilities reported a shortage of disposable masks (67.2%) and hand sanitizer alcohol (56.7%). Isolation of COVID-19 patients in private rooms was possible only in 52.7% of the facilities. The majority of facilities (73.3%) could not accept COVID-19 dialysis patients due to lack of space and manpower. Nosocomial transmission of COVID-19 occurred in 4.0% of the facilities. Of those infected, 51.9% were staff. CONCLUSIONS: This survey revealed that most hemodialysis facilities in Japan had improved implementation of infection control measures and had shortage of PPEs and disinfectants, though some facilities did not implement infection prevention measures adequately, mainly due to the limited space of the facility. It may be recommended that each facility immediately establishes isolation measures to prepare for the pandemic of COVID-19. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s41100-021-00350-y.

COVID-19 of dialysis patients in Japan: Current status and guidance on preventive measures.

In Japan, the first case of COVID-19 in dialysis patients was reported on March 1, 2020. A total of 31 cases were reported by April 10, and it increased to 95 by May 15. Thereafter, with the rapid increase in the number of COVID-19 cases in the general population since late March, there was a not surprising increase in the number of COVID-19 cases in dialysis patients. The mortality rate is 16.2% (16/99 cases) in dialysis patients, which is higher than 5.3% (874/16 532 cases) in the general population. This higher mortality rate in dialysis patients with COVID-19 might be related to their age; the majority of COVID-19 cases are aged between 70 and 90 years old in dialysis patients, compared with between 20 and 60 years old in the general population. As COVID-19 presents with severe symptoms and is associated with a high mortality rate in dialysis patients, dialysis patients who have contracted severe acute respiratory syndrome coronavirus 2 infection confirmed by polymerase chain reaction testing are required to be hospitalized under Japanese government policy. In cases of COVID-19 hospitalizations, it is essential to prevent nosocomial infection. Therefore, patients must be sufficiently instructed in infection prevention and robust measures to prevent contraction and spread of the infection must be taken at dialysis facilities.