Publications by authors named "Tomokazu Shimizu"
Article Synopsis
- The study focuses on the impact of SARS-CoV-2 on kidney transplant (KTx) recipients, highlighting limited data on their treatment and prognosis during the pandemic.
- Out of 282 KTx patients infected with the virus, 6.7% experienced severe outcomes, with certain underlying health conditions increasing the risk of complications.
- Treatment strategies evolved over time in response to new variants, with antiviral drugs being administered as they gained approval.
Article Synopsis
- Solid organ transplant (SOT) recipients show poor antibody production against SARS-CoV-2 post-vaccination, raising concerns about their immune responses.
- A study involving 614 SOT recipients vaccinated with mRNA vaccines revealed an overall seropositivity rate of 43% one month after the second dose, increasing to 70% by six months.
- Kidney, lung, and simultaneous pancreas-kidney transplant recipients had lower antibody levels at 3 and 6 months compared to other organ types, indicating slower antibody acquisition relative to the general population.
Article Synopsis
- The study compared the effectiveness and safety of new anemia treatments (HIF-PHis) in chronic kidney disease (CKD) patients who have received kidney transplants (KTRs) versus those who have not (non-KTRs).
- Researchers analyzed data from 82 patients before and after starting treatment with roxadustat or daprodustat, focusing on hemoglobin (Hb) levels and adverse events.
- Findings showed both groups had significant increases in Hb levels, but KTRs had a higher rate of thrombotic events, indicating that while the treatments are similarly effective, KTRs require careful monitoring for blood clot risks.
Background: Kidney allograft rejections are orchestrated by a variety of immune cells. Because of the complex histopathologic features, accurate pathological diagnosis poses challenges even for expert pathologists. The objective of this study was to unveil novel spatial indices associated with transplant rejection by using a spatial bioinformatic approach using 36-plex immunofluorescence image data.
View Article and Find Full Text PDFBackground: The number of marginal living kidney donors has increased. Medically complex donors who have hypertension, older age, or low estimated glomerular filtration rate (eGFR) have been more likely to be used.
Methods: We conducted a retrospective cohort study of living kidney donors at a single center.
Background: There are limitations in treating advanced prostate cancer (PC), especially castration-resistant (CR) cases, in renal transplant recipients (RTRs). We describe the case of RTR with metastatic CRPC (mCRPC) treated with docetaxel.
Case Report: A 60-year-old man with end-stage renal disease due to autosomal-dominant polycystic kidney disease (ADPKD) underwent living-related kidney transplantation.
Recent developments in intensive desensitization protocols have enabled kidney transplantation in human leukocyte antigen (HLA)-sensitized recipients. However, cases of active antibody-mediated rejection (AABMR), when they occur, are difficult to manage, graft failure being the worst-case scenario. We aimed to assess the impact of our desensitization and AABMR treatment regimen and identify risk factors for disease progression.
View Article and Find Full Text PDFBackground/aim: Occasionally, candidate renal transplant recipients (RTRs) are incidentally diagnosed with prostate cancer (PCa) during pre-transplant screening examinations; however, their clinical course remains unclear. This study aimed to clarify the clinical course of RTR diagnosed with PCa during pre-transplant screening tests.
Patients And Methods: Between April 2008 and April 2022, 15 candidates for RTRs were newly diagnosed with PCa during the screening test.
Introduction: Herein, we discuss clinicopathological analyses of cases of chronic renal allograft arteriopathy (CRA) after renal transplantation and clarify the mechanisms underlying the development and prognostic significance of CRA.
Methods: CRA was diagnosed in 34 renal allograft biopsy specimens (BSs) obtained from 27 renal transplant patients who were followed up at the Department of Urology and Transplant Surgery, Toda Chuo General Hospital, between January 2010 and December 2020.
Results: CRA was diagnosed at a median of 33.
Background: We report a case of suspected hyperacute rejection during living kidney transplantation.
Case Report: A 61-year-old man underwent kidney transplantation in November 2019. Before the transplantation, immunologic tests revealed the presence of anti-HLA antibodies but not donor-specific HLA antibodies.
Objectives: To evaluate the 10-year efficacy and safety of a prolonged-release tacrolimus-based combination immunosuppressive regimen on longer-term outcomes in living donor kidney transplantation.
Methods: Data from Japanese living donor kidney transplant recipients (n = 410) maintained on continuous prolonged-release tacrolimus-based immunosuppression from 2009-2013 were analyzed with a median follow-up of 9.9 years.
Objectives: Many researchers have demonstrated that the seropositivity rate after SARS-CoV-2 coronavirus vaccination is lower in patients receiving oral immunosuppressants. In this article, we report on a comparative study on the seropositivity rate after 2 doses of coronavirus vaccine before or after kidney transplant.
Materials And Methods: We studied 111 recipients vaccinated after transplant, 19 patients vaccinated before transplant, and 10 healthy patients.
Introduction: We present a case of novel coronavirus disease-2019 that underwent combination therapy with nivolumab and ipilimumab for metastatic renal cell carcinoma.
Case Presentation: A 50-year-old man complained of anorexia and weight loss. Contrast-enhanced computed tomography revealed a solid mass of 57 mm in diameter with cysts in the right kidney, along with liver, lung, and multiple bone metastases.
Pediatric renal transplantation is associated with various surgical complications due to the complexity of the technique and the often-fragile condition of patients with end-stage renal disease. We evaluated the surgical complications associated with renal transplantation via the extraperitoneal approach in pediatric recipients. This retrospective study enrolled 280 patients younger than 16 years old who underwent renal transplantation via the extraperitoneal approach: 216 patients underwent transplant placement in the iliac fossa like in adults, and 64 underwent transplant placement in the distal part of the original renal lower pole (the extraperitoneal cavity).
View Article and Find Full Text PDFBackground: Casirivimab-imdevimab is a cocktail of 2 monoclonal antibodies designed to prevent infection by SARS-CoV-2, the virus that causes COVID-19. Casirivimab-imdevimab has been approved in Japan for treating mild to moderate COVID-19; however, to our knowledge, there are no reports of its use after kidney transplant from a live donor. Everolimus, an antineoplastic chemotherapy drug, is expected to be effective in inhibiting the spread of SARS-CoV-2 and preventing its replication, which may facilitate treatment.
View Article and Find Full Text PDFBackground: We reviewed the results of cases of kidney transplant (KTx) that were conducted at the Toda Chuo General Hospital, a private hospital located in Saitama, Japan.
Methods: A total of 312 patients with end-stage renal failure underwent KTx between January 1992 and December 2019 at Toda Chuo General Hospital. There were 191 men and 121 women.
Background: The assessment of frailty before and after kidney transplantation is becoming more important in the aging population. It is recommended to recognize the post-transplant risks and establish a treatment strategy. We report the case of a patient who underwent 2 laparotomy hemostasis procedures due to frailty after kidney transplantation.
View Article and Find Full Text PDFBackground: Patients undergoing organ transplantation are immunosuppressed and already at risk of various diseases. We report about a patient who underwent ABO-incompatible kidney transplantation after coronavirus disease 2019 (COVID-19) without a recurrence of infection.
Case Report: A 68-year-old woman presented with end-stage renal failure owing to primary autosomal dominant polycystic kidney disease; accordingly, hemodialysis was initiated in September 2020.
Background: Coronavirus disease 2019 (COVID-19) infection may become more severe in those who have undergone kidney transplantation than in the general population. False-negative reverse transcription-polymerase chain reaction (RT-PCR) results have been reported for COVID-19 infection. Patients might carry infection even though RT-PCR results are negative.
View Article and Find Full Text PDFBackground: We present a rare case of de novo renal cell carcinoma that developed in an allograft kidney 14 years after transplantation.
Case Report: A 39-year-old man underwent living donor kidney transplantation from his mother. After 14 years, routine screening ultrasonography revealed a solid mass of 30-mm diameter in the kidney allograft.
Background: Little is known about the outcome of living-donor kidney transplantation (LDKT) performed in low-volume centers lacking the services of full-time transplant surgeons. This retrospective cohort study assessed the outcome of LDKT performed in a low-volume center by visiting transplant surgeons from a high-volume center and managed perioperatively by transplant nephrologists.
Methods: We compared Japanese adult patients who had no donor-specific antibodies and underwent LDKT between 2006 and 2015 either in a low-volume (n = 31) or high-volume (n = 481) center.
Background: Tacrolimus (TAC) is a key immunosuppressant drug for kidney transplantation (KTx). However, the optimal serum trough level of TAC for good long-term outcomes remains unclear. This study aimed to investigate the relationship between the maintenance TAC trough level and the appearance of de novo donor-specific anti-human leukocyte antigen (HLA) antibodies (dnDSAs).
View Article and Find Full Text PDFAim: We aimed to perform a clinicopathological analysis of cases presenting with borderline changes (BC) after renal transplantation and discuss whether BC might be clinically or pathologically important.
Materials And Methods: BC was diagnosed in 22 renal allograft biopsy specimens obtained from 20 renal transplant recipients between April 2010 and March 2019 after follow-up at the Department of Transplant Surgery, Kidney Center, Toda Chuo General Hospital.
Results: BC was diagnosed at a median of 500 days following transplantation.
Aim: We discuss the clinicopathologic analyses of cases of biopsy specimens (BS) after renal transplantation and clarify the mechanisms underlying the development and prognostic significance of chronic vascular rejection (CVR).
Patients: CVR was diagnosed in 30 renal allograft BS obtained from 23 renal transplant patients being followed up at the Department of Urology and Transplant Surgery, Toda Chuo General Hospital, between January 2010 and August 2017.
Results: CVR was diagnosed at a median of 33.