Head and neck squamous cell carcinoma (HNSCC) in solid organ transplant recipients - Results from the scientific registry of transplant recipients (SRTR) database.

BACKGROUND: Solid organ transplant recipients have an elevated risk of cancer following organ transplantation than the age-adjusted general population. We assessed incidence of head and neck squamous cell carcinoma (HNSCC) in heart, lung, and liver recipients. BASIC PROCEDURES/METHODS: This retrospective cohort study included 124,966 patients from the United States Scientific Registry of Transplant Recipients (SRTR) database who received heart, lung, or liver transplantation between 1991 and 2010. Follow-up data were available until 2018. Patients with prevalent HNSCC at transplantation were excluded. Incident cases of HNSCC post organ transplantation were identified, and incidence rates (per 100,000 person-years) were reported by gender, race, organ type, year and age at organ transplantation. MAIN FINDINGS: The majority of patients received liver transplantation (58.64 %), followed by heart (28.64 %), and lung (12.72 %) transplantation. During follow-up, 4.14 % patients developed HNSCC. Overall incidence rate of HNSCC was 426.76 per 100,000 person-years. Male recipients had a higher HNSCC incidence rate than female recipients (571.8 and 177.0 per 100,000 person-years, respectively). Lung recipients had the highest overall HNSCC incidence rate (1273.6 per 100,000 person-years), followed by heart (644.2 per 100,000 person-years), and liver recipients (207.1 per 100,000 person-years). Overall, an increase in HNSCC incidence rate was observed with increase in age at organ transplantation. An increase in incidence rates of HNSCC over time was observed in lung recipients; however, incidence rates decreased over time in heart recipients. CONCLUSION: Solid organ transplant recipients have a high incidence of HNSCC following organ transplantation, and the incidence varies by type of organ received.

COVID-19 Vaccine in Lung and Liver Transplant Recipients Exceeds Expectations: An Italian Real-Life Experience on Immunogenicity and Clinical Efficacy of BNT162b2 Vaccine.

This study assessed humoral and T cell-mediated immune responses to the BNT162b2 vaccine in orthotopic liver transplant (OLT) and lung transplant (LUT) recipients who received three doses of the vaccine from March 2021 at our institution. Serum samples were collected 60 days post-second and third dose to quantify antibodies against the spike region of SARS-CoV-2 while whole blood samples were collected to analyze the SARS-CoV-2-specific T-cell response using an IFN-γ ELISpot assay. We enrolled 244 OLT and 120 LUT recipients. The third dose increased antibody titres in OLT recipients (from a median value of 131 after the second dose to 5523 IU/mL, p < 0.001) and LUT recipients (from 14.8 to 1729 IU/mL, p < 0.001). T-cell response also increased in OLT recipients (from 8.5 to 23 IFN-γ SFU per 250,000 PBMC, p < 0.001) and LUT recipients (from 8 to 15 IFN-γ SFU per 250,000 PBMC, p < 0.001). A total of 128 breakthrough infections were observed: two (0.8%) OLT recipients were hospitalized due to COVID-19 and one died (0.4%); among LUT recipients, seven were hospitalized (5.8%) and two patients died (1.7%). In conclusion, the three-dose schedule of the BNT162b2 vaccine elicited both humoral and T cell-mediated responses in solid organ transplant recipients. The risk of severe COVID-19 post-vaccination was low in this population.

Assessing the Predictive Value of Methicillin-Resistant Staphylococcus aureus Nares Colonization Among Transplant Recipients and Patients With Neutropenia.

Background: Methicillin-resistant Staphylococcus aureus (MRSA) nares screening has been shown to be a powerful antibiotic stewardship tool for MRSA infections within 7 days of screening across a variety of anatomical locations given the high negative predictive value (NPV). However, the utility outside of 7 days and among transplant recipients and patients with neutropenia is less clear. Methods: This was a retrospective cohort study across Veterans Affairs medical centers in the United States from 1 January 2007 to 1 January 2023 of patients tested for MRSA colonization and who had a subsequent positive bacterial culture within 28 days of MRSA sc---reening. Sensitivity, specificity, positive predictive value, and NPV were calculated across different time points and anatomical culture locations. Results: The cohort consisted of 686 174 patients, 6 277 437 MRSA nares tests, and 2 446 766 positive bacterial cultures within 28 days of MRSA testing. The NPV of MRSA nares screening for ruling out a MRSA infection within 28 days was 95.8% across all anatomical culture sites. The NPV was 97.9% among patients with neutropenia and 97.5% in solid organ and hemopoietic stem cell transplant recipients. Conclusions: MRSA nares screening can reliably be used for de-escalation of anti-MRSA therapy within 28 days of bacterial culture for all patients, including solid organ and hematopoietic transplant recipients and patients with neutropenia.

Squamous cell carcinoma in solid organ transplant recipients: Review of the literature. / Carcinoma escamoso cutáneo en pacientes trasplantados de órgano sólido: revisión de la literatura.

Solid organ transplant recipients (SOTRs) exhibit an elevated incidence and aggressiveness of squamous cell carcinomas (SCCs) due to their immunosuppression. These tumors are associated with a heightened risk of metastasis and increased mortality. Therefore, an appropriate management of these patients is essential to improve their prognosis. Given the scarcity of studies on non-melanoma skin cancers (NMSCs) in SOTRs, this article aims to summarize and analyze the evidence gathered to date regarding therapeutic approaches, personalized monitoring, and prevention strategies for SCCs in these patients. Additionally, recent advancements in understanding SCCs within this patient group are also documented.

Changes in the Quality of Life and Nutrition Markers in Transition From End-Stage Kidney Disease to Kidney Transplantation: Insights From a Vietnamese Cohort.

Background Malnutrition is strongly associated with lower quality of life (QoL) and lower survival rates in patients with end-stage kidney disease. However, the impact of renal transplantation on nutrition factors and QoL is unclear. Therefore, this study aims to assess changes in QoL and investigate the relationships with nutrition factors among kidney transplant recipients (KTRs). Materials and methods A longitudinal study included 86 dialysis patients aged 18-65 years who underwent primary kidney transplantation (KTx) and were followed up for one year. Body weight, biochemical parameters, and QoL data were collected before transplantation (T0) and at six months (T6) and 12 months (T12) post-transplantation. Effect size (ES) was used to measure the impact of KTx on QoL and nutritional status from T0 to T12. The predictors of QoL were calculated with ß-coefficients and p<0.05 in linear regression. Results The ES of transplantation on the QoL of KTRs was large, at 1.1 for health change, 0.9 for physical health, and moderate (0.7) for mental health (MH) over one year. Hemoglobin and malnourished were affected by KTx, with ES being 2.4 and 0.6, respectively. Linear regression showed that physical health was predicted by hemoglobin (ß=0.12, p<0.01), phosphorus (ß=7.82, p<0.05), and dose of mycophenolate mofetil (MMF) (ß=-0.01, p<0.05). Mental health was predicted by obesity (ß=-7.63, p<0.05), hemoglobin (ß=0.11, p<0.05), and phosphorus (ß=8.49, p<0.01). Health change was indicated by nutritional risk index (NRI) score (ß=0.47, p<0.05), total cholesterol (ß=3.39, p<0.01), and kidney function (ß=0.15, p<0.05). Conclusions The transition from end-stage kidney disease to transplantation has positive impacts on QoL and nutrition markers. Nutritional status, kidney function, and the dose of mycophenolate mofetil are significant determinants of QoL in KTRs.

Adequacy to immunosuppression management guidelines in kidney transplant recipients with severe COVID-19 pneumonia: a practice survey.

Introduction: Coronavirus disease 2019 (COVID-19) poses an important risk of morbidity and of mortality, in patients after solid organ transplantation. Recommendations have been issued by various transplantation societies at the national and European level to manage the immunosuppressive (IS) regimen upon admission to intensive care unit (ICU). Method: The aim of this study was to evaluate the adequacy of IS regimen minimization strategy in kidney transplant recipients hospitalized in an ICU for severe COVID-19, in relation to the issued recommendations. Results: The immunosuppressive therapy was minimized in all patients, with respectively 63% and 59% of the patients meeting the local and european recommendations upon admission. During ICU stay, IS was further tapered leading to 85% (local) and 78% (european) adequacy, relative to the guidelines. The most frequent deviation was the lack of complete withdrawal of mycophenolic acid (22%). Nevertheless, the adequacy/inadequacy status was not associated to the ICU- or one-year-mortality. Discussion: In this single-center cohort, the only variable associated with a reduction in mortality was vaccination, emphasizing that the key issue is immunization prior to infection, not restoration of immunity during ICU stay.

Refractory/Resistant Cytomegalovirus Infection in Transplant Recipients: An Update.

Despite the significant progress made, CMV infection is one of the most frequent infectious complications in transplant recipients. CMV infections that become refractory or resistant (R/R) to the available antiviral drugs constitute a clinical challenge and are associated with increased morbidity and mortality. Novel anti-CMV therapies have been recently developed and introduced in clinical practice, which may improve the treatment of these infections. In this review, we summarize the treatment options for R/R CMV infections in adult hematopoietic cell transplant and solid organ transplant recipients, with a special focus on newly available antiviral agents with anti-CMV activity, including maribavir and letermovir.

Impact of COVID-19 on liver transplant recipients: A nationwide cohort study evaluating hospitalization, transplant rejection, and inpatient mortality.

BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic has posed a major public health concern worldwide. Patients with comorbid conditions are at risk of adverse outcomes following COVID-19. Solid organ transplant recipients with concurrent immunosuppression and comorbidities are more susceptible to a severe COVID-19 infection. It could lead to higher rates of inpatient complications and mortality in this patient population. However, studies on COVID-19 outcomes in liver transplant (LT) recipients have yielded inconsistent findings. AIM: To evaluate the impact of the COVID-19 pandemic on hospital-related outcomes among LT recipients in the United States. METHODS: We conducted a retrospective cohort study using the 2019-2020 National Inpatient Sample database. Patients with primary LT hospitalizations and a secondary COVID-19 diagnosis were identified using the International Classification of Diseases, Tenth Revision coding system. The primary outcomes included trends in LT hospitalizations before and during the COVID-19 pandemic. Secondary outcomes included comparative trends in inpatient mortality and transplant rejection in LT recipients. RESULTS: A total of 15720 hospitalized LT recipients were included. Approximately 0.8% of patients had a secondary diagnosis of COVID-19 infection. In both cohorts, the median admission age was 57 years. The linear trends for LT hospitalizations did not differ significantly before and during the pandemic (P = 0.84). The frequency of in-hospital mortality for LT recipients increased from 1.7% to 4.4% between January 2019 and December 2020. Compared to the pre-pandemic period, a higher association was noted between LT recipients and in-hospital mortality during the pandemic, with an odds ratio (OR) of 1.69 [95% confidence interval (CI): 1.55-1.84), P < 0.001]. The frequency of transplant rejections among hospitalized LT recipients increased from 0.2% to 3.6% between January 2019 and December 2020. LT hospitalizations during the COVID-19 pandemic had a higher association with transplant rejection than before the pandemic [OR: 1.53 (95%CI: 1.26-1.85), P < 0.001]. CONCLUSION: The hospitalization rates for LT recipients were comparable before and during the pandemic. Inpatient mortality and transplant rejection rates for hospitalized LT recipients were increased during the COVID-19 pandemic.

Translation and cross-cultural adaptation of the Kidney Transplant Questionnaire 25 to Greek.

BACKGROUND: Kidney transplantation leads to continuous improvement in the survival rates of kidney transplant recipients (KTRs) and has been established as the treatment of choice for patients with end-stage kidney disease. Health-related quality of life (HRQoL) has become an important outcome measure. It is highly important to develop reliable methods to evaluate HRQoL with disease-specific questionnaires. AIM: To translate the disease-specific instrument Kidney Transplant Questionnaire 25 (KTQ-25) to the Greek language and perform a cross-cultural adaptation. METHODS: The translation and adaptation of the original English version of the KTQ-25 to the Greek language were performed based on the International Quality of Life Assessment. RESULTS: Eighty-four KTRs (59 males; mean age 53.5 ± 10.7 years; mean estimated glomerular filtration rate 47.7 ± 15.1 mL/min/1.73 m2; mean transplant vintage 100.5 ± 83.2 months) completed the Greek version of the KTQ-25 and the 36-item Short-Form Health Survey, and the results were used to evaluate the reliability of the Greek KTQ-25. The Cronbach alpha coefficients for all the KTQ-25 dimensions were satisfactory (physical symptoms = 0.639, fatigue = 0.856, uncertainty/fear = 0.661, appearance = 0.593, emotions = 0.718, total score = 0.708). The statistically significant correlation coefficients among the KTQ-25 dimensions ranged from 0.226 to 0.644. The correlation coefficients of the KTQ-25 dimensions with the SF-36 physical component summary (PCS) ranged from 0.196 to 0.550; the correlation coefficients of the KTQ-25 with the SF-36 mental component summary (MCS) ranged from 0.260 to 0.655; and the correlation coefficients of the KTQ-25 with the total scores with the SF-36 PCS and MCS were 0.455 and 0.613, respectively. CONCLUSION: According to the findings, the Greek version of the KTQ-25 is valid and reliable for administration among kidney transplant patients in Greece.

Evaluation of the Current Urgency-Based Lung Allocation System in Korea with Simulation of the Eurotransplant Lung Allocation Score.

PURPOSE: Due to the shortage of lung donors relative to the number of patients waiting for lung transplantation (LTx), more than one-third of patients on the waitlist have died without receiving LTx in Korea. Therefore, the importance of fair and effective allocation policies has been emphasized. This study investigated the characteristics of the current urgency-based allocation system in Korea by simulating the Eurotransplant lung allocation score (ET-LAS) using a nationwide multi-institutional registry for LTx in Korea. MATERIALS AND METHODS: This study used data from the Korean Organ Transplantation Registry (KOTRY), along with additional retrospective data for ET-LAS calculation. A total of 194 patients were included in this study between January 2015 and December 2019. The Korean urgency definition classifies an LTx candidate as having statuses 0-3 according to urgency. The ET-LAS was analyzed according to the Korean urgency status. RESULTS: In total, 92 patients received lung transplants at status 0, 85 at status 1, and 17 at status 2/3. The ET-LAS showed a bimodal distribution with distinct peaks corresponding to status 0 and non-status 0. There was no significant difference in the ET-LAS among non-status 0 patients. In logistic and decision tree analyses, oxygen supplementation methods, particularly oxygen masks and high-flow nasal cannulas, were significantly associated with a high ET-LAS (≥50) among non-status 0 patients. CONCLUSION: Simulation of the ET-LAS with KOTRY data showed that the Korean urgency definition may not allocate lungs by urgency, especially for patients in non-status 0; therefore, it needs to be revised.

A novel approach to therapeutic drug monitoring of Ciclosporin in pediatric renal transplant recipients using volumetric absorptive microsampling (VAMS) - Teaching old dog new tricks.

BACKGROUND AND AIMS: Ciclosporin (CSA) is an immunosuppressive agent that requires therapeutic drug monitoring (TDM). High partitioning in erythrocytes indicates that whole blood (WB) is a suitable matrix for CSA determination. Alternative sampling strategies, such as volumetric absorptive microsampling (VAMS), are novel possibilities for blood collection during TDM for various analytes, including immunosuppressants. This technique is attractive for vulnerable pediatric patients, including home-based self-sampling, remote therapy, and adherence control. MATERIALS AND METHODS: This study aimed to develop and validate a new method for CSA determination based on liquid chromatography-tandem mass spectrometry (LC-MS/MS) of WB and VAMS samples. Additionally, these methods were applied for CSA determination in clinical samples from pediatric transplant recipients. A strong point of this study is the assessment of an external proficiency testing scheme. RESULTS: Both methods were successfully validated within the 1-2000 ng/mL calibration range, with LOD 0.5 and 1 ng/mL for WB and VAMS methods, respectively. All the validation parameters fulfilled the international acceptance criteria for bioanalytical methods. Cross-validation confirmed the interchangeability of the LC-MS/MS method developed in this study. CONCLUSION: This study developed and validated novel methods for CSA determination in whole blood and VAMS using LC-MS/MS. Clinical validation and proficiency testing confirmed their utility in routine clinical practice.

Clinical Characteristics and Epidemiological Analysis of Pneumocystis Jirovecii Pneumonia Infection in Kidney Transplant Patients with Trimethoprim-Sulfamethoxazole Dose Reduction Prophylaxis Strategy.

Background: The administration of trimethoprim-sulfamethoxazole (TMP-SMX) for the prophylaxis of Pneumocystis jirovecii pneumonia (PJP) has proven to be highly efficacious in individuals who have undergone kidney transplantation. Nevertheless, the potential for severe adverse reactions associated with this treatment cannot be overlooked, and the determination of an optimal dosage regimen continues to be a matter of investigation. The current study evaluated the effectiveness of low-dose TMP-SMX for PJP prophylaxis in kidney transplant patients and conducted an analysis of the clinical characteristics and epidemiological trends in patients with PJP infection. Methods: This retrospective analysis studied electronic medical records of 1763 kidney transplant recipients from 2017 to 2020. These patients were initially prescribed a daily half-strength TMP-SMX (40 mg/200 mg), and the efficacy of this regimen was assessed during a follow-up period of 3-51 months. Results: Under our PJP prevention and adjustment strategy, 24 patients were infected with PJP. The overall morbidity of PJP infection in our study was 1.36%, corroborates with findings from previously published studies. Among these 24 patients, up to 87.5% had their dosage adjusted due to increased creatinine or other adverse reactions, the most frequent dose was daily quarter-strength TMP-SMX (20 mg/100 mg). TMP-SMX prophylaxis successfully postponed and distributed the onset of PJP, with the mean duration from transplantation to the occurrence of PJP being 13.50±7.11 months. Conclusion: Daily administration of half-strength TMP-SMX can effectively prevent PJP, and prolonging prophylaxis with this medication may potentially reduce the incidence of infection.

Creatine homeostasis and the kidney: comparison between kidney transplant recipients and healthy controls.

Creatine is a natural nitrogenous organic acid that is integral to energy metabolism and crucial for proper cell functioning. The kidneys are involved in the first step of creatine production. With kidney transplantation being the gold-standard treatment for end-stage kidney disease, kidney transplant recipients (KTR) may be at risk of impaired creatine synthesis. We aimed to compare creatine homeostasis between KTR and controls. Plasma and urine concentrations of arginine, glycine, guanidinoacetate, creatine and creatinine were measured in 553 KTR and 168 healthy controls. Creatine intake was assessed using food frequency questionnaires. Iothalamate-measured GFR data were available in subsets of 157 KTR and 167 controls. KTR and controls had comparable body weight, height and creatine intake (all P > 0.05). However, the total creatine pool was 14% lower in KTR as compared to controls (651 ± 178 vs. 753 ± 239 mmol, P < 0.001). The endogenous creatine synthesis rate was 22% lower in KTR as compared to controls (7.8 ± 3.0 vs. 10.0 ± 4.1 mmol per day, P < 0.001). Despite lower GFR, the plasma guanidinoacetate and creatine concentrations were 21% and 41% lower in KTR as compared to controls (both P < 0.001). Urinary excretion of guanidinoacetate and creatine were 66% and 59% lower in KTR as compared to controls (both P < 0.001). In KTR, but not in controls, a higher measured GFR was associated with a higher endogenous creatine synthesis rate (std. beta: 0.21, 95% CI: 0.08; 0.33; P = 0.002), as well as a higher total creatine pool (std. beta: 0.22, 95% CI: 0.11; 0.33; P < 0.001). These associations were fully mediated (93% and 95%; P < 0.001) by urinary guanidinoacetate excretion which is consistent with production of the creatine precursor guanidinoacetate as rate-limiting factor. Our findings highlight that KTR have a disturbed creatine homeostasis as compared to controls. Given the direct relationship of measured GFR with endogenous creatine synthesis rate and the total creatine pool, creatine supplementation might be beneficial in KTR with low kidney function.Trial registration ID: NCT02811835.Trial registration URL: https://clinicaltrials.gov/ct2/show/NCT02811835 .

Clinical efficacy and safety of switching from eculizumab to ravulizumab in adult patients with aHUS- real-world data.

BACKGROUND: The complement factor 5 (C5)-inhibitor eculizumab has been established as standard-of-care for the treatment of atypical hemolytic uremic syndrome (aHUS). In 2021, the long-acting C5-inhibitor ravulizumab was approved, extending intervals of intravenous treatment from two to eight weeks resulting in improvement of quality of life for patients and lowering direct and indirect therapy associated costs. METHODS: This multicenter, retrospective data analysis of 32 adult patients with aHUS (including 10 kidney transplant recipients) treated with eculizumab for at least three months and switched to ravulizumab aims to evaluate the safety and efficacy of switching medication in the real-world setting. Hematologic parameters, kidney function, concurrent therapy and aHUS associated events were evaluated three months before and until up to 12 months after switching to ravulizumab. RESULTS: Mean age (range) at ravulizumab initiation was 41 years (19-78 years) and 59% of the patients were female. Genetic analysis was available for all patients with 72% showing a pathogenic variant. Median time (range) on eculizumab before switching was 20 months (3-120 months). No new events of TMA or worsening of renal function were reported during up to 12 months of follow-up during ravulizumab treatment. CONCLUSIONS: This is the largest, non-industry derived, multi-center retrospective analysis of adult patients with aHUS switching C5-inhibitor treatment from eculizumab to ravulizumab in the real-world setting. Switching to ravulizumab was safe and efficient resulting in sustained hematological stability and preservation of renal function.

Induction Therapies Determine the Distribution of Perforin and Granzyme B Transcripts in Kidney Transplant Recipients.

Peripheral blood mononuclear cells contain secretory granules with Perforin and Granzyme B for defense against pathogens. The objective of the present study was to compare the effects of immunosuppressive induction therapies on Perforin and Granzyme B transcripts in kidney transplant recipients. Transcripts were determined in 408 incident kidney transplant recipients eight days posttransplant using quantitative real-time PCR. Compared to 90 healthy subjects, the median Perforin transcripts were lower in kidney transplant recipients with blood-group ABO-incompatible donors (N = 52), compatible living donors (N = 130), and deceased donors (N = 226) (25.7%; IQR, 6.5% to 46.0%; 31.5%; IQR, 10.9% to 57.7%; and 35.6%; IQR, 20.6% to 60.2%; respectively; p = 0.015 by the Kruskal-Wallis test). Kidney transplant recipients who were treated with thymoglobulin (N = 64) had significantly lower Perforin as well as Granzyme B compared to all other induction therapies (N = 344) (each p < 0.001). Receiver operator characteristics analysis showed that both Perforin (area under curve, 0.919) and Granzyme B (area under curve, 0.915) indicated thyroglobulin-containing induction therapies. Regression analysis showed that both reduction in plasma creatinine and human leukocyte antigen mismatches were positively associated with elevated Perforin/Granzyme B transcript ratio posttransplant. We conclude clinical parameters and therapies affect Perforin and Granzyme B transcripts posttransplant.

Risk factors and multi-pathogen infections in kidney transplant recipients with omicron variant pneumonia: a retrospective analysis.

BACKGROUND: Kidney transplant recipients (KTRs) are at an elevated risk of progressing to severe infections upon contracting COVID-19. We conducted a study on risk factors and multi-pathogen infections in KTRs with SARS-CoV-2 Omicron variant. METHODS: KTRs were subjected to a thorough etiological evaluation. Whenever feasible, they were also provided with bronchoscopy and bronchoalveolar lavage to enable metagenomic next-generation sequencing (mNGS), ideally within a 48-hour window post-admission. We performed a retrospective analysis for pathogens and risk factors of KTRs with the COVID-19 virus variant Omicron. RESULTS: We included thirty patients in our study, with sixteen exhibiting single infection of COVID-19 and fourteen experiencing co-infections, predominantly with Pneumocystis jirovecii. Notably, patients with severe cases demonstrated significantly elevated levels of C-reactive protein (CRP) and interleukin-6 compared to those with moderate cases (P < 0.05). Furthermore, individuals whose conditions progressed had markedly higher baseline serum creatinine levels than those without such progression (P < 0.05). The presence of heart failure, acute exacerbation of renal dysfunction, and a history of opportunistic infections were significantly associated with a higher likelihood of deterioration and hospital admission due to the SARS-CoV-2 Omicron variant, as compared to the control group (P < 0.05). In subsequent follow-up analysis, the all-cause rehospitalization rate was observed to be 21.4%, with Pneumocystis jirovecii infection accounting for half of these cases. CONCLUSION: Among KTRs, a significant coinfection rate of 47% was observed, with Pneumocystis jirovecii emerging as the predominant pathogen in these cases. The development of heart failure, acute exacerbation of chronic renal dysfunction, and a prior history of opportunistic infections have been identified as potential risk factors that may contribute to clinical deterioration in KTRs. Additionally, Pneumocystis jirovecii infection has been established as a critical factor influencing the rate of all-cause rehospitalization within this patient population.

Physical Exercise in Kidney Renal Recipients: Where Have We Come?

BACKGROUND: Kidney transplantation constitutes the most effective therapeutic option for patients suffering from end-stage renal disease but remains burdened by a high incidence of cardiovascular disease. To date, exercise is an important preventive strategy that has been underestimated; in kidney transplant patients, exercise programs lead to an improvement in cardiorespiratory performance, muscle strength, arterial stiffness, and patients' quality of life perception. SUMMARY: The nephrology and transplant community have moved from generic suggestions to specific indications regarding frequency, intensity, time, type, volume, and progression of physical exercise both in the pre- and posttransplant phase. The latest guidelines from the World Health Organization for patients with chronic conditions propose a combination of aerobic, muscle-strengthening, and multicomponent exercises (e.g., balance) to improve health. Based on recent evidence, a combined exercise program (aerobic and strength exercise) is largely proposed to kidney transplant recipients. Aerobic exercise should be performed at an intensity >60% of theoretical maximum heart rate or maximum oxygen uptake possibly every day, and strength training should be performed at a >60% the estimate single maximum repetition, at least 2 times per week. KEY MESSAGES: Physical exercise should be personalized in relation to the patient's baseline performance; increases must be progressive and gradual. Regular physical activity should also be recommended to patients awaiting for a transplant. Eventually, organizational models based on a network of nephrology units, transplant centers, sports medicine centers, and fitness center or outdoor gym are essential elements for overcoming the logistical barriers for prescribing and carrying out regular physical activity.

Improving prediction of tacrolimus concentration using a combination of population pharmacokinetic modeling and machine learning in chinese renal transplant recipients.

Aims: The population pharmacokinetic (PPK) model-based machine learning (ML) approach offers a novel perspective on individual concentration prediction. This study aimed to establish a PPK-based ML model for predicting tacrolimus (TAC) concentrations in Chinese renal transplant recipients. Methods: Conventional TAC monitoring data from 127 Chinese renal transplant patients were divided into training (80%) and testing (20%) datasets. A PPK model was developed using the training group data. ML models were then established based on individual pharmacokinetic data derived from the PPK basic model. The prediction performances of the PPK-based ML model and Bayesian forecasting approach were compared using data from the test group. Results: The final PPK model, incorporating hematocrit and CYP3A5 genotypes as covariates, was successfully established. Individual predictions of TAC using the PPK basic model, postoperative date, CYP3A5 genotype, and hematocrit showed improved rankings in ML model construction. XGBoost, based on the TAC PPK, exhibited the best prediction performance. Conclusion: The PPK-based machine learning approach emerges as a superior option for predicting TAC concentrations in Chinese renal transplant recipients.