Safely navigating kidney transplantation during the COVID-19 pandemic: the Singapore General Hospital's experience

Background

The coronavirus disease 2019 (COVID-19) pandemic curtailed transplant activities worldwide, driven by concerns about increased COVID-19-related mortality among kidney transplant recipients (KTRs), infections originating from donors, and decreased availability of surgical and intensive care resources as healthcare resources are reallocated for pandemic response. We examined the outcomes of KTRs at our center before and during the COVID-19 pandemic.

Methods

We conducted a retrospective single-center cohort study examining the characteristics and outcomes of patients undergoing kidney transplantation during two periods January 1, 2017 to December 31, 2019 (pre-COVID-19 era) and January 1, 2020 to June 30, 2022 (COVID-19 era). We reviewed perioperative and COVID-19 infection-related outcomes in both groups.

Results

A total of 114 transplants were performed during the pre-COVID-19 era, while 74 transplants were conducted during the COVID-19 era. No differences in baseline demographics were observed. Additionally, there were no significant differences in perioperative outcomes, except for a longer cold ischemia time during the COVID-19 era. However, this did not result in an increased incidence of delayed graft function. Among the KTRs infected with COVID-19 during the pandemic era, no severe complications such as pneumonia, acute kidney injury, or death were reported.

Conclusions

With the global transition to an endemic phase of COVID-19, it is imperative to revitalize organ transplant activities. Effective containment workflow, good vaccination uptake, and prompt COVID-19 treatment are essential to ensure that transplants can proceed safely.

beta-Amyloid peptide vaccination results in marked changes in serum and brain Abeta levels in APPswe/PS1DeltaE9 mice, as detected by SELDI-TOF-based ProteinChip technology

Although the pathogenesis of Alzheimer's disease (AD) is not fully understood, growing evidence indicates that the deposition of beta-amyloid (Abeta) and the local reactions of various cell types to this protein play major roles in the development of the disease. Immunization with the Abeta 1-42 peptide has been reported to decrease Abeta deposits in the brains of mutant amyloid precursor protein (APP/V717F) transgenic (tg) mice (Schenk et al. Immunization with amyloid-beta attenuates Alzheimer-disease-like pathology in the PDAPP mouse. Nature 1999;400:173-177). We have replicated this finding in APPswe/PS1DeltaE9 tg mice, which also develop Abeta deposits in the brain. The immunized animals developed high titers of antibodies against Abeta 1-42 in serum, and Abeta deposits in the brains were significantly reduced. Using surface-enhanced laser desorption/ionization (SELDI) mass spectrometry and ProteinChip((R)) technology, we detected trends toward increased soluble Abeta peptide in the brain and a decrease in assayable Abeta peptide in the serum of immunized compared with control animals. This last finding raises the possibility that anti-Abeta antibodies in the periphery sequester Abeta peptides or target them for degradation and in this way contribute to the enhanced Abeta clearance from the brain in immunized animals.