Immune response, phenotyping and molecular graft surveillance in kidney transplant recipients following severe acute respiratory syndrome coronavirus 2 vaccination.

BACKGROUND: Understanding immunogenicity and alloimmune risk following severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination in kidney transplant recipients is imperative to understanding the correlates of protection and to inform clinical guidelines. METHODS: We studied 50 kidney transplant recipients following SARS-CoV-2 vaccination and quantified their anti-spike protein antibody, donor-derived cell-free DNA (dd-cfDNA), gene expression profiling (GEP), and alloantibody formation. RESULTS: Participants were stratified using nucleocapsid testing as either SARS-CoV-2-naïve or experienced prior to vaccination. One of 34 (3%) SARS-CoV-2 naïve participants developed anti-spike protein antibodies. In contrast, the odds ratio for the association of a prior history of SARS-CoV-2 infection with vaccine response was 18.3 (95% confidence interval 3.2, 105.0, p < 0.01). Pre- and post-vaccination levels did not change for median dd-cfDNA (0.23% vs. 0.21% respectively, p = 0.13), GEP scores (9.85 vs. 10.4 respectively, p = 0.45), calculated panel reactive antibody, de-novo donor specific antibody status, or estimated glomerular filtration rate. CONCLUSIONS: SARS-CoV-2 vaccines do not appear to trigger alloimmunity in kidney transplant recipients. The degree of vaccine immunogenicity was associated most strongly with a prior history of SARS-CoV-2 infection.

Impact of the 2014 kidney allocation system changes on trends in A2/A2B into B kidney transplantation and organ procurement organization reporting of donor subtyping.

The current kidney allocation system (KAS) preferentially allocates kidneys from blood type A2 or A2B (A/A2B) donors to blood type B candidates. We used national data to evaluate center-level performance of A2/A2B to B transplants, and organ procurement organization (OPO) reporting of type A or AB donor subtyping, in 5-year time periods prior to (2009-2014) and following (2015-2019) KAS implementation. The number of centers performing A2/A2B to B transplants increased from 17 pre-KAS to 76 post-KAS, though this still represents only a minority of centers (7.3% pre-KAS and 32.6% post-KAS). For high-performing centers, the median net increase in A2/A2B to B transplants was 19 cases (range -2-72) per center in the 5 years post-KAS. The median net increase in total B recipient transplants was 21 cases (range -17-119) per center. Despite requirements for performance of subtyping, in 2019 subtyping was reported on only 56.4% of A/AB donors. This translates into potential missed opportunities for B recipients, and even post-KAS up to 2322 A2/A2B donor kidneys may have been allocated for transplantation as A/AB. Further progress must be made both at center and OPO levels to broaden implementation of A2/A2B to B transplants for the benefit of underserved recipients.

The Prevalence of Nephrolithiasis and Associated Risk Factors Among the Population of the Riyadh Province, Saudi Arabia.

Background and objective Kidney stones, also referred to as nephrolithiasis or renal calculi, is a condition where crystal depositions are formed within the kidney and ideally excreted from the body via the urethra with no pain; however, larger calculi may cause significant pain and require further medical assistance. The vast majority of patients who develop renal calculi form calcium stones, which are either a composition of calcium oxalate or calcium phosphate. Other types include uric acid, struvite, and cysteine. While kidney stones are one of the most significant diseases among the Saudi population, which require an acute emergency intervention to prevent serious long-term complications, there are limited studies published regarding this condition in Saudi communities. In light of this, we performed this study to assess the prevalence, incidence, and risk factors of kidney stones among the population of Riyadh, Saudi Arabia. Methods This was a cross-sectional study conducted in Riyadh, Saudi Arabia between August and October 2023, aiming to estimate the prevalence and risk factors of nephrolithiasis among residents of the Riyadh province. Data were collected through an electronic questionnaire in both Arabic and English and distributed via social media in addition to barcode handouts in various selected venues in Riyadh. The questionnaire involved 12 questions categorized into three sections. The first section obtained demographical information while the second section collected data about the past medical history of the participants. Lastly, the third section aimed to assess the prevalence of nephrolithiasis among participants or any history of the condition among their families. Results A total of 1,043 participants were surveyed, of whom 533 were males (51.1%). The prevalence of kidney stones was reported in 98 individuals (9.4%) overall. Individuals in the age groups of 36-50, 51-60, and >60 years showed significantly more renal stone prevalence than those in younger age groups (p<0.001). The prevalence was found to be higher in participants who were smokers, diabetic, hypertensive, and those who suffered from inflammatory bowel disease (IBD), gout, chronic kidney disease (CKD), hyperthyroidism, and hyperparathyroidism. Participants who took calcium supplements or had a positive family history of renal stones were found to have a higher prevalence of renal stones as well. However, only hypertension, gout, and family history showed any statistical significance (p<0.05). Conclusions A direct correlation was observed between hypertension, gout, positive family history, and aging and an increased prevalence of kidney stones among the inhabitants of the Riyadh province. Therefore, we encourage the local authorities to raise awareness of kidney stones and their related risk factors among the general public. Moreover, further local studies need to be conducted to gain deeper insights into kidney stone prevalence, especially pertaining to associated comorbidities and the pattern of the disease itself.