Effect of education on sun-safe behaviour in kidney transplant recipients.

BACKGROUND: Organ transplant recipients (OTR) are more likely to develop skin cancer than the general population. One of the main components of the exposome that triggers the development of skin tumours is solar ultraviolet (UV) radiation. To reduce the incidence of harmful consequences of sun exposure, sun protection education is needed for patients taking long-term immunosuppressive drugs. METHODS: In a previous study, we assessed the sun-safe behaviour of 221 OTR using a questionnaire before and after transplantation and personally educated the patients about proper sun protection. After the education, there were no further reminder presentations. Presently, the sun protection and sun seeking habits of the available 176 of these patients were questioned to assess the long-term effect of the previous sun protection education. RESULTS: Two-four years after the education, more patients wore hats and protected their skin with long-sleeved clothing than before the education. In terms of sun seeking habits, both occupational and recreational sun exposure decreased significantly. Significantly fewer people went on holiday after transplantation, but those who went on holiday spent significantly less time in the sun. CONCLUSION: The long-term positive effects of education can be seen both in the patients' sun protection and in their sun seeking habits. However, the long-term goal is to maintain these results and thereby reduce the likelihood of skin tumours and consequently the associated tumour death.

Long-term outcome of pediatric renal transplantation with donors younger than 6 years.

BACKGROUND: Renal transplantation is currently the best treatment option for patients with end-stage renal disease. However, the use of kidneys from donors under 6 years of age as a possibility to increase the organ pool in pediatric recipients remains a controversial matter. We aimed to investigate whether donor age is associated to the long-term functionality of the renal graft. Likewise, we analyzed the adaptation of the graft to the ascending functional requirements in the pediatric patient. METHODS: Retrospective study of the results obtained in pediatric recipients transplanted with grafts from donors between 3 and 6 years of age, comparing them with those of grafts from donors older than 6 years. Among the variables compared are cumulative graft survival, renal size, need for antiproteinuric therapy, GFR, incidence of rejection, pyelonephritis, renal failure and surgical or tumor complications. RESULTS: A total of 43 transplants were performed with donors aged 3-6 years, and 42 transplants with donors older than 6 years. Cumulative graft survival at 5 years was 81% for the younger donor group compared to 98% for the older donor group (p < .05). At 8 years, cumulative graft survival for donors <6 years was 74%. As for the mean estimated graft survival, it was 11.52 years for the younger donor group and 14.51 years for older donors. During follow-up, the younger donor group presented greater renal enlargement and need for antiproteinuric therapy. The older donors group had a higher GFR during the first year of follow-up, which then equalized in both groups. There were no statistically significant differences in the incidence of acute or chronic rejection, acute pyelonephritis, acute renal failure or surgical or tumor complications. CONCLUSIONS: Renal transplants of grafts equal to or less than 6 years old have good short-term and acceptable long-term results in pediatric patients.

Effect of pre-emptive rituximab on EBV DNA levels and prevention of post-transplant lymphoproliferative disorder in pediatric kidney transplant recipients: A case series from the pediatric nephrology research consortium.

BACKGROUND: There are scant data on the effect of rituximab on EBV DNA levels and prevention of post-transplant lymphoproliferative disorder (PTLD) in pediatric kidney transplant recipients with EBV DNAemia. METHODS: Kidney transplant recipients with EBV DNAemia treated with rituximab to prevent PTLD between 7/1999 and 7/2019 at five pediatric centers were included. Those with confirmed PTLD at the onset of rituximab were excluded. Primary outcomes included percentage change in EBV DNAemia and occurrence of PTLD post rituximab. RESULTS: Twenty-six pediatric kidney transplant recipients were included. Median age at transplant was 4 years (IQR 2.1-10.3). EBV DNA load monitoring by qPCR was performed at 1-3 month intervals. EBV DNAemia onset occurred at a median of 73 days post-transplant (IQR 52-307), followed by DNAemia peak at a median of 268 days (IQR 112-536). Rituximab was administered at a median of 9 days post peak (IQR 0-118). Rituximab regimens varied; median dose 375 mg/m2 (IQR 375-439) weekly for 1-4 doses per course. Following rituximab, EBV DNA load decreased to <10% of baseline at 120 days in 20/26 patients; however, only 30% achieved complete resolution at last follow-up (median 2094 days post-transplant [IQR 1538-3463]). Two (7%) developed PTLD at 915 and 1713 days post rituximab. All recipients had functioning grafts. One death occurred in a child with PTLD following remission due to unrelated reasons. CONCLUSIONS: In the largest pediatric kidney transplant recipient case series with EBV DNAemia given rituximab to prevent PTLD, rituximab achieved a short-term reduction in DNA load; however, recurrent DNAemia is common.

Transcriptomics-based identification of TYROBP and TLR8 as novel macrophage-related biomarkers for the diagnosis of acute rejection after kidney transplantation.

Macrophages play an important role in the development and progression of acute rejection after kidney transplantation. The study aims to investigate the biological role and significance of macrophage-associated genes (MAG) in acute rejection after kidney transplantation. We utilized transcriptome sequencing results from public databases related to acute rejection of kidney transplantation for comprehensive analysis and validation in animal experiments. We found that a large number of immune-related signaling pathways are activated in acute rejection. PPI protein interaction networks and machine learning were used to establish a Hub gene consisting of TYROBP and TLR8 for the diagnosis of acute rejection. The single-gene GSEA enrichment analysis and immune cell correlation analysis revealed a close correlation between the expression of Hub genes and immune-related biological pathways as well as the expression of multiple immune cells. In addition, the study of TF, miRNAs, and drugs provided a theoretical basis for regulating and treating the Hub genes in acute rejection. Finally, the animal experiments demonstrated once again that acute rejection can aggravate kidney tissue damage, apoptosis level, and increase the release of inflammatory factors. We established and validated a macrophage-associated diagnostic model for acute rejection after kidney transplantation, which can accurately diagnose the biological alterations in acute rejection after kidney transplantation.

A pig kidney supporting human physiology.

Because of the global shortage of donor kidneys, xenotransplantation emerges as a potential solution for individuals with kidney failure who face challenges in securing a suitable donor kidney. A study featured in this month's issue of Kidney International assesses the kidney physiology of a porcine kidney transplanted into a brain-dead human with kidney failure, demonstrating life-sustaining physiological function for 7 days. Together with preclinical nonhuman primate studies, decedent models provide complementary data for development of clinical kidney xenotransplantation.

Development and validation of a novel nomogram model for predicting delayed graft function in deceased donor kidney transplantation based on pre-transplant biopsies.

BACKGROUND: Delayed graft function (DGF) is an important complication after kidney transplantation surgery. The present study aimed to develop and validate a nomogram for preoperative prediction of DGF on the basis of clinical and histological risk factors. METHODS: The prediction model was constructed in a development cohort comprising 492 kidney transplant recipients from May 2018 to December 2019. Data regarding donor and recipient characteristics, pre-transplantation biopsy results, and machine perfusion parameters were collected, and univariate analysis was performed. The least absolute shrinkage and selection operator regression model was used for variable selection. The prediction model was developed by multivariate logistic regression analysis and presented as a nomogram. An external validation cohort comprising 105 transplantation cases from January 2020 to April 2020 was included in the analysis. RESULTS: 266 donors were included in the development cohort, 458 kidneys (93.1%) were preserved by hypothermic machine perfusion (HMP), 96 (19.51%) of 492 recipients developed DGF. Twenty-eight variables measured before transplantation surgery were included in the LASSO regression model. The nomogram consisted of 12 variables from donor characteristics, pre-transplantation biopsy results and machine perfusion parameters. Internal and external validation showed good discrimination and calibration of the nomogram, with Area Under Curve (AUC) 0.83 (95%CI, 0.78-0.88) and 0.87 (95%CI, 0.80-0.94). Decision curve analysis demonstrated that the nomogram was clinically useful. CONCLUSION: A DGF predicting nomogram was developed that incorporated donor characteristics, pre-transplantation biopsy results, and machine perfusion parameters. This nomogram can be conveniently used for preoperative individualized prediction of DGF in kidney transplant recipients.

Sociodemographic disparities in sodium-glucose cotransporter-2 inhibitor use among US kidney transplant recipients: An observational study of real-world pharmacy records.

BACKGROUND: Recent clinical trials demonstrate benefits of sodium-glucose cotransporter-2 inhibitors (SGLT2i) in patients with chronic kidney disease, but data on use in kidney transplant (KTx) recipients are limited. METHODS: We examined a novel database linking SRTR registry data for KTx recipients (2000-2021) with outpatient fill records from a large pharmaceutical claims warehouse (2015-2021). Adult (≥18 years) KTx recipients treated with SGLT2i were compared to those who received other noninsulin diabetes medications without SGLT2i. Characteristics associated with SGLT2i use were quantified by multivariable logistic regression (adjusted odds ratio, 95%LCLaOR95%UCL). RESULTS: Among 18 988 KTx recipients treated with noninsulin diabetes agents in the study period, 2224 filled an SGLT2i. Mean time from KTx to prescription was 6.7 years for SGLT2i versus 4.7 years for non-SGLT2i medications. SGLT2i use was more common in Asian adults (aOR, 1.091.311.58) and those aged > 30-59 years (compared with 18-30 years) or with BMI > 35 kg/m2 (aOR, 1.191.411.67), and trended higher with self-pay status. SGLT2i use was lower among KTx recipients who were women (aOR, .79.87.96), Black (aOR, .77.881.00) and other (aOR, .52.751.07) race, publicly insured (aOR, .82.921.03), or with less than college education (aOR, .78.87.96), and trended lower in those age 75 years and older. SGLT2i use in KTx patients increased dramatically in 2019-2021 (aOR, 5.015.636.33 vs. prior years). CONCLUSION: SGLT2i use is increasing in KTx recipients but varies with factors including race, education, and insurance. While ongoing study is needed to define risks and benefits of SGLT2i use in KTx patients, attention should also focus on reducing treatment disparities related to sociodemographic traits.

Continuous flow local anesthetic wound infusion for post-operative analgesia following kidney transplantation.

BACKGROUND: Some patients with end stage renal disease are or will become narcotic-dependent. Chronic narcotic use is associated with increased graft loss and mortality following kidney transplantation. We aimed to compare the efficacy of continuous flow local anesthetic wound infusion pumps (CFLAP) with patient controlled analgesia pumps (PCA) in reducing inpatient narcotic consumption in patients undergoing kidney transplantation. MATERIALS AND METHODS: In this single-center, retrospective analysis of patients undergoing kidney transplantation, we collected demographic and operative data, peri-operative outcomes, complications, and inpatient oral morphine milligram equivalent (OME) consumption. RESULTS: Four hundred and ninety-eight patients underwent kidney transplantation from 2020 to 2022. 296 (59%) historical control patients received a PCA for postoperative pain control and the next 202 (41%) patients received a CFLAP. Median age [53.5 vs. 56.0 years, p = .08] and BMI [29.5 vs. 28.9 kg/m2, p = .17] were similar. Total OME requirement was lower in the CFLAP group [2.5 vs. 34 mg, p < .001]. Wound-related complications were higher in the CFLAP group [5.9% vs. 2.7%, p = .03]. Two (.9%) patients in the CFLAP group experienced cardiac arrhythmia due to local anesthetic toxicity and required lipid infusion. CONCLUSIONS: Compared to PCA, CFLAP provided a 93% reduction in OME consumption with a small increase in the wound-related complication rate. The utility of local anesthetic pumps may also be applicable to patients undergoing any unilateral abdominal or pelvic incision.

Association of physical activity with fractures in kidney transplant recipients: A Korean nationwide cohort study.

Kidney transplant recipients are at high risk for fractures, primarily due to post-transplant bone disease. This retrospective cohort study analyzed data from the Korean National Health Insurance Service, including 10 083 kidney transplant recipients examined from 2009 to 2017. We assessed fracture incidence, emphasizing vertebral and hip fractures, and the association of physical activity and traditional risk factors with fracture risk. Kidney transplant recipients were categorized into three groups according to physical activity levels: non-activity, metabolic equivalent of task (MET) 1-499, and MET ≥500. Physical activity was associated with a decreased risk of all types of fractures: any (MET 1-499: adjusted hazard ratio (aHR) .75; 95% confidence interval (CI) .62-.92, MET ≥500: aHR .84; 95% CI .70-1.00), vertebral (MET 1-499: aHR .69; 95% CI .49-.98, MET ≥500: aHR .67; 95% CI .49-.91), and hip (MET 1-499: aHR .43; 95% CI .23-.81) fractures. Additionally, older age, female sex, and diabetes were associated with an increased fracture risk. The assessment of physical activity and traditional risk factors could improve fracture risk prediction. Our findings emphasize the need for further research to establish optimal physical activity recommendations for fracture prevention in kidney transplant recipients.

Kidney after liver transplantation does not have an increased risk of rejection compared to liver alone.

BACKGROUND: Simultaneous liver kidney (SLK) transplant protects against acute cellular rejection. In 2017, UNOS implemented a "safety net" policy to allow patients with renal recovery to avoid renal transplantation. Whether kidney after liver transplantation (KALT) increases the risk of rejection is unknown. METHODS: We performed a retrospective analysis of the Organ Procurement and Transplantation Network (OPTN) database of adult patients who received liver transplant, SLK or KALT between 2010 and 2020. We examined rejection of the liver within 6 months and 1 year of the liver transplant, as well as rejection of the kidney within 6 months and 1 year of receiving the kidney, as well as patient and graft loss. RESULTS: Sixty-six thousand seventy-nine patients were transplanted; 60 168 with liver transplant alone, 5627 with SLK, and 284 with KALT. Acute or chronic liver rejection rates within 6 or 12 months were statistically higher in the KALT group (10.0% and 10.9%) compared to the SLK group (6.1% and 7.5%), but comparable to the LTA group (9.3% and 11.1%). Kidney rejection and graft survival rates were not different. Liver graft survival was worse in KALT than SLK or LTA (Kaplan-Meier estimates .61 vs. .89 and .90), but these patients were more ill at the time of transplantation. KDPI and LDRI scores were notably lower in the SLK than KALT group. Patient survival was not clinically different between the groups. CONCLUSION: KALT does not increase the risk of acute or chronic kidney rejection. SLK has a lower risk of early liver rejection, but this effect diminishes by one year to being not clinically different compared to KALT. Given that KALT is immunologically safe, and potentially avoids unnecessary renal graft use, it should be preferred over SLK. BRIEF SUMMARY: Patients undergoing sequential kidney after liver transplant do not have an increased risk of liver or kidney rejection when compared to liver transplant alone or simultaneous liver and kidney transplant.

COVID-19 and renal allograft rejection: insight from controlled and non-controlled studies.

AIM: Kidney transplant recipients (KTRs), due to their immunosuppressed status, are potentially more susceptible to both the severe effects of COVID-19 and complications in their transplanted organ. The aim of this study is to investigate whether COVID-19 infection increases the risk of rejection in kidney transplant recipients (KTRs). METHODS: This study involved a detailed literature review, conducted using PubMed, with the search being completed by September 7th, 2023. The search strategy incorporated a combination of relevant keywords: 'COVID', 'Renal', 'Kidney', 'Transplant', and 'Rejection'. The results from controlled and uncontrolled studies were separately collated and analyzed. RESULTS: A total of 11 studies were identified, encompassing 1,179 patients. Among these, two controlled studies reported the incidence of rejection in KTRs infected with COVID-19. Pooling data from these studies revealed no significant statistical correlation between COVID-19 infection and biopsy-proven rejection (p = 0.26). In addition, nine non-controlled studies were found, with rejection incidences ranging from 0% to 66.7%. The majority of these studies (eight out of nine) had small sample sizes, ranging from 3 to 75 KTRs, while the largest included 372 KTRs. The combined rejection rate across these studies was calculated to be 11.8%. CONCLUSION: In conclusion, the limited number of published controlled studies revealed no statistically significant association between COVID-19 infection and biopsy-proven rejection among KTRs. However, the broader analysis of non-controlled studies showed a variable rejection incidence with a pooled rejection rate of 11.8%. There is insufficient high-quality data to explore the association of COVID-19 infection and rejection.

Anuria after kidney transplantation diagnosed as early recurrence of focal segmental glomerulosclerosis combined with acute calcineurin inhibitor nephrotoxicity: a case report and literature review.

BACKGROUND: Primary focal segmental glomerulosclerosis (FSGS) is a glomerular disease that sometimes recurs in patients after kidney transplantation (KT) and increases the risk of graft loss. Proteinuria is a common early sign of recurrent FSGS, but an abrupt decrease in urine volume is rare. Herein, we report a patient with early recurrence of FSGS with anuria following KT. CASE PRESENTATION: A 55-year-old man with end-stage kidney disease caused by primary FSGS experienced anuria on postoperative day 2 following deceased donor KT. Laboratory results revealed that serum tacrolimus trough levels were consistently elevated at the time of anuria. At first, we considered acute calcineurin inhibitor (CNI) nephrotoxicity based on graft biopsy on light microscopy, laboratory findings, and clinical courses. However, the allograft function did not recover even after discontinuation of CNI, and recurrent FSGS was diagnosed 2 weeks later on electron microscopy. A total of 13 sessions of plasmapheresis and two administrations of rituximab (375 mg/m2) were required to treat recurrent FSGS. The patient achieved a partial response, and the spot urine protein-to-creatinine ratio decreased from 15.5 g/g creatinine to 5.2 g/g creatinine. At 5 months following KT, the serum creatinine level was stable at 1.15 mg/dL. CONCLUSIONS: These findings highlight that anuria can occur in cases of early recurrence of FSGS combined with acute CNI nephrotoxicity.

Association of Coronary Calcium Score on Cardiac PET During Pre-Kidney Transplant Assessment with Persistent Hyperparathyroidism: A Retrospective Study.

BACKGROUND Secondary hyperparathyroidism and coronary calcifications are common complications in chronic kidney disease. However, the relation between coronary calcium score (CCS) and persistent hyperparathyroidism (pHPT) after kidney transplantation (KT) remains unknown. MATERIAL AND METHODS This was a single-center retrospective study of KT candidates from January 2017 to May 2020. We collected patients' demographics, cardiovascular (CV) risk factors, and the findings of pre-KT CV imaging. We also collected parathyroid hormone (PTH) values before KT, at 1-6 months, 6-12 months, and 12-24 months after KT. We defined pHPT as PTH ≥25.5 pmol/L after 12 months post-KT. RESULTS A total of 111 KT recipients (KTRs) with a mean age of 50.4 years were included, of which 62.2% were men and 77.5% were living-donor KTRs. Dialysis modality used before KT was peritoneal dialysis in 9.9% and hemodialysis in 82.9%. Dialysis vintage was 3±2.9 years. The prevalence of pHPT was 24.3% (n=27), and the prevalence of severe coronary calcifications (CCS >400 Agatston units) was 19.8% (n=22). PTH values at baseline, 1-6 months, 6-12 months, and 12-24 months were not different among between CCS >400 or CCS <400 groups. However, pHPT after KT was significantly more prevalent in KTRs with severe CCS (37% vs 14.3%, p=0.014). Severe CCS was associated with less improvement of PTH values after KT (r=0.288, p=0.020). Otherwise, the findings of cardiac PET and coronary angiogram were not significantly different between pHPT and non-pHPT patients. CCS >400 was independently associated with pHPT after transplant (aOR=18.8, P=0.012). CONCLUSIONS Severe CCS on pre-KT cardiac assessment is associated with pHPT after KT.

Outcome of surgical parathyroidectomy for tertiary hyperparathyroidism in kidney transplant recipients: tertiary hyperparathyroidism should not be ignored, for the sake of precious allografts.

Tertiary hyperparathyroidism is a complication of kidney transplantation. This complicated condition carries over from the dialysis period and varies according to the function of the transplanted allograft. Treatments include pharmacotherapy (mainly using calcimimetics) and parathyroidectomy, but calcimimetics are currently not covered by the national insurance system in Japan. Two types of parathyroidectomy can be performed: subtotal parathyroidectomy; and total parathyroidectomy with partial autograft. Both types can be expected to improve hypercalcemia. Concerns about the postoperative deterioration of allograft function are influenced by preoperative allograft function, which is even more likely to be affected by early surgery after kidney transplantation. In general, transient deterioration of allograft function after surgery is not expected to affect graft survival rate in the medium to long term. Tertiary hyperparathyroidism in kidney transplant recipients negatively impacts allograft and patient survival rates, and parathyroidectomy can be expected to improve prognosis in both kidney recipients and dialysis patients. However, studies offering high levels of evidence remain lacking.

Incidence of De Novo Post-Transplant Malignancies in Thai Adult Kidney Transplant Recipients: A Single-Center, Population-Controlled, Retrospective Cohort Study at the Highest Volume Kidney Transplant Center in Thailand.

Kidney transplant recipients (KTRs) are at increased risk of developing de novo post-transplant malignancies (PTMs), with regional differences in types with excess risk compared to the general population. A single-center, population-controlled, retrospective cohort study was conducted at a tertiary care center in Thailand among all adults who underwent their first kidney transplant from 1986 to 2018. Standardized incidence ratios (SIRs) of malignancy by age, sex, and place of residence were obtained using data from the National Cancer Registry of Thailand as population control. There were 2,024 KTRs [mean age, 42.4 years (SD 11.4); female patients, 38.6%] during 16,495 person-years at risk. Of these, 125 patients (6.2%) developed 133 de novo PTMs. The SIR for all PTMs was 3.85 (95% CI 3.22, 4.56), and for pooled solid and hematologic PTMs, it was 3.32 (95% CI 2.73, 3.99). Urothelial malignancies had the largest excess risk, especially in women [female SIR 114.7 (95% CI 66.8, 183.6); male SIR 17.5 (95% CI 8.72, 31.2)]. The next two most common cancers were non-Hodgkin's lymphoma and skin cancer [SIR 20.3 (95% CI 13.6, 29.1) and 24.7 (95% CI 15.3-37.8), respectively]. Future studies are needed to identify the risk factors and assess the need for systematic screening among PTMs with excess risk in KTRs.

Beyond the First Year: Epidemiology and Management of Late-Onset Opportunistic Infections After Kidney Transplantation.

Late opportunistic infections (OI) occurring beyond the first year after kidney transplantation (KT) are poorly described and not targeted by prophylactic strategies. We performed a ten-year retrospective monocentric cohort study describing epidemiology, risk factors and impact of late OI occurring 1 year after KT. We included clinically symptomatic OI requiring treatment besides BK virus nephropathy. Control groups included early OI occurring in the first year after KT, and KT recipients without OI since KT and alive with a functional allograft at 1 year. Among 1066 KT recipients, 185 (19.4%) presented a first episode of OI 21.0 (8.0-45.0) months after KT: 120 late OI (64.9%) and 65 early OI (35.1%). Late OI were mainly viral (N = 83, 69.2%), mostly herpes zoster (HZ) (N = 36, 43.4%). Pneumocystis represented most late fungal infections (N = 12/25, 48%). Compared to early OI, we reported more pneumocystis (p = 0.002) and less invasive aspergillosis (p = 0.01) among late OI. Patients with late OI were significatively younger at KT (54.0 ± 13.3 vs. 60.2 ± 14.3 years, p = 0.05). Patient and allograft survival rates between late OI and control groups were similar. Only age was independently associated with mortality. While late OI were not associated with higher mortality or graft loss, implementing prophylactic strategies might prevent such infections.

Association of T Cell Subsets and Platelet/Lymphocyte Ratio with Long-Term Complications in Kidney Transplant Recipients.

BACKGROUND Infection and chronic rejection remain major issues for kidney transplant recipients (KTRs). The present study aimed to explore the association of CD4+/CD8+ T cell ratio (CD4+/CD8+) and platelet/lymphocyte ratio (PLR) with long-term infection and chronic renal insufficiency in KTRs. MATERIAL AND METHODS KTRs admitted to a single hospital from June 2014 to December 2021 were divided into infected (164) and non-infected (107) groups based on clinical data. The levels of CD4+/CD8+, PLR, neutrophil/lymphocyte ratio (NLR), and C-reactive Protein (CRP) in KTRs with long-term infection, and their correlation with chronic kidney insufficiency, were analyzed. Survival analysis was used to evaluate the risk factors for long-term infection and chronic kidney insufficiency. RESULTS Spearman correlation analysis showed that chronic kidney insufficiency was positively correlated with PLR, and negatively correlated with CRP and CD4+/CD8+ (P<0.05). PLR was positively correlated with CRP, procalcitonin, erythrocyte sedimentation rate, and NLR, but negatively with CD4+/CD8+. CD4+/CD8+ was correlated with CRP, NLR, and PLR (P<0.05). Survival analysis and survival curves showed that PLR and CD4+/CD8+ were risk factors for long-term infection and chronic kidney insufficiency in KTRs (P<0.05). CONCLUSIONS CD4+/CD8+ and PLR were associated with long-term complications, and were risk factors for long-term infection and chronic kidney insufficiency in KTRs.

Torque Teno Virus (TTV) in Renal Transplant Recipients: Species Diversity and Variability.

Torque Teno Virus (TTV) is a nonpathogenic and ubiquitous ssDNA virus, a member of the Anelloviridae family. TTV has been postulated as a biomarker in transplant patients. This study aimed to determine the TTV species diversity and variability in renal transplant recipients and to associate species diversity with the corresponding TTV viral load. From 27 recipients, 30 plasma samples were selected. Viral load was determined using two real-time PCR assays, followed by RCA-NGS and ORF1 phylogenetic analysis. The TTV diversity was determined in all samples. Variability was determined in three patients with two sequential samples (pre- and post-transplantation). Most of the samples presented multiple TTV species, up to 15 different species were detected. In the pre-transplant samples (n = 12), the most prevalent species were TTV3 (75%) and TTV13 (75%), and the median number of species per sample was 5 (IQR: 4-7.5). TTV3 was also the most prevalent (56%) in the post-transplant samples (n = 18), and the median number of species was 2 (IQR: 1.8-5.5). No significant correlation between the number of species and viral load was found. The number and type of TTV species showed total variability over time. We report high TTV species diversity in Argentinian recipients, especially in pre-transplant period, with total intra-host variability. However, we found no significant correlation between this high diversity and TTV viral load.

SARS-CoV-2 Omicron infection in a cohort of hospitalized kidney transplant recipients: Risk factors of severity.

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron is a major coronavirus variant, which was prevalent in China at the end of 2022 and caused widespread infection. As an immunosuppressed group, renal transplant recipients with SARS-CoV-2 infection are prone to developing serious pneumonia or an adverse outcome event if the infection is not treated in time. Here, we analyze the possible risk factors of infection severity. MATERIALS AND METHODS: 92 cases of moderate and severe SARS-CoV-2 infection after renal transplantation were collected. Statistical methods, including Fisher's tests, F test, Spearman relative values, and multi-parameter logistic regression models, were used to analyze the risk factors for severe SARS-CoV-2 infection in renal transplant recipients. RESULTS: 44 cases complicated with hypertension were observed in the study cohort, among whom 30 were severe (OR: 4.63, p < 0.001). Out of 51 male patients infected with Omicron, 30 male patients presented with severe SARS-CoV-2 (OR: 2.45, p = 0.039). In renal transplant patients, hypertension comorbidity was closely correlated with clinical presentation (R = 0.369, p < 0.001). Blood routine test, chemistries, and additional indices showed increased neutrophils and C-reactive protein in patients with severe disease compared with the moderate group according to one-way analysis of variance (p = 0.004), while CD3 (p = 0.02) and CD4 (p = 0.04) showed lower expressional levels. We also observed meaningful correlations between neutrophil levels and hypertension comorbidity (R = 0.222, p = 0.034) and between interleukin-6 (IL-6) levels and diabetes comorbidity (R = 0.315, p = 0.011), with IL-6 considered a key factor in the context of coronavirus disease. CONCLUSION: Renal transplant recipients were generally susceptible to infection with the Omicron variant, with a more pronounced incidence of severe illness observed in the group with hypertension comorbidity.