Vaičiūnienė, Rūta

Įprastinė transplantuoto inksto būklės stebėsena remiasi inksto funkcijos rodiklių kraujyje ir šlapime tyrimais bei inksto biopsija. Visgi, šie metodai sulaukia kritikos, nes dažnai atspindi jau pažengusius pokyčius ir neleidžia aptikti ankstyvosios patologijos bei laiku užkirsti kelią jos progresavimui. Dėl šios priežasties aktyviai ieškoma papildomų neinvazinių biožymenų. Magnetinio rezonanso tomografija (MRT), gebanti įvertinti ne tik struktūrinius bet ir fiziologinius organų procesus, nefrologijos srityje vis dar naudojama palyginti retai. Šio tyrimo tikslas – įvertinti neinvazinio struktūrinio MRT ir paciento volemijos rodiklių klinikinę bei prognostinę vertę po inksto transplantacijos. Tyrimo rezultatai atskleidė, kad plaučių hipervolemijos būklė prieš transplantaciją, įvertinta ultragarsu, koreliuoja tiek su lėtesniu transplantato funkcijos atsistatymu, tiek su prastesne funkcija po vienų metų. Tuo tarpu MRT tyrime gautos sąsajos tarp ADC bei T1 relaksacijos laikų žemėlapių reikšmių ir aGFG, proteinurijos bei albuminurijos. Taip pat stebėta T1 žievės-šerdies diferenciacijos rodiklio koreliacija su inkstų struktūriniais pokyčiais kartotiniuose tyrimuose ir lėtinės fibrozės progresavimu. MRT pritaikymas, nuosekliai vertinant transplantato struktūrinę būklę, ir šių radinių susiejimas su laboratorinių tyrimų bei protokolinių biopsijų duomenimis gali padėti anksčiau identifikuoti pacientus, kuriems kyla didesnė lėtinio transplantato nepakankamumo rizika.

Both obesity and chronic kidney disease (CKD) are increasingly recognized as global epidemics. Their escalating incidence and far-reaching health implications highlight the urgent need for comprehensive prevention and management strategies. This review aims to clarify how obesity interacts with end-stage kidney disease (ESKD) and how to improve the management of obese patients receiving kidney replacement therapy. It also explores underlying mechanisms, current treatments, future directions, and ongoing controversies. By highlighting this intricate relationship, the review seeks to enhance clinical practice and promote further research toward more personalized care for this vulnerable population. Obesity is frequent in dialysis patients and creates challenges related to body composition, metabolism, and treatment. While higher body mass index (BMI) may appear to improve survival, this paradox does not offset the cardiovascular and functional risks of visceral and sarcopenic obesity. Obesity also increases post-transplant complications and can limit access to transplantation. Lifestyle changes rarely achieve lasting weight loss, whereas bariatric surgery—especially sleeve gastrectomy—can improve transplant eligibility with fewer complications. Weight-loss medications may be used before transplantation but remain insufficiently studied in ESKD. After transplantation, weight-reduction efforts should continue, with pharmacotherapy preferred over bariatric surgery. Comprehensive assessment strategies and individualized management approaches in ESKD patients are essential to optimize outcomes in this growing patient population.

Background and Objectives: Non-invasive imaging biomarkers for the early detection of chronic kidney allograft injury are needed to improve long-term transplant outcomes. T1 mapping by magnetic resonance imaging (MRI) has emerged as a promising method to assess renal structure and function. This study aimed to determine the potential of MRI as a diagnostic tool for evaluating graft function and structural changes in kidney grafts 1 year after transplantation. Materials and Methods: Thirty-four kidney transplant recipients were prospectively recruited, with 27 completing the follow-up at one year. Renal MRI at 3T was performed to acquire T1, T2, and apparent diffusion coefficient (ADC) maps. Clinical parameters, including estimated glomerular filtration rate (eGFR), albumin-to-creatinine ratio (ACR), protein-to-creatinine ratio (PCR), and histological IF/TA scores, were collected. MRI parameters were compared across the groups stratified by clinical and histological markers. Diagnostic accuracy was assessed using receiver operating characteristic (ROC) analysis. Results: At 1 year, T1 corticomedullary differentiation (CMD) values were significantly higher in patients with elevated ACR (≥3 mg/mmol), PCR (≥15 mg/mmol), and mild to moderate or severe IF/TA, reflecting a reduction in the corticomedullary gradient. T1 CMD demonstrated moderate-to-good diagnostic performance in detecting ACR (AUC 0.791), PCR (AUC 0.730), and IF/TA (AUC 0.839). No significant differences were observed in T2 or ADC values across these groups. T1 CMD also showed a significant positive correlation with ACR but not with eGFR, suggesting a closer association with structural rather than functional deterioration. Conclusions: T1 mapping, particularly T1 CMD, shows promise as a non-invasive imaging biomarker for detecting chronic allograft injury and monitoring renal function 1 year after kidney transplantation.

Background/Objectives: Kidney transplantation (kTx) is the preferred treatment for end-stage kidney disease. Limited evaluation of structural changes in transplanted kidneys hinders the timely prediction of disease progression and the implementation of treatment modifications. Protocol biopsies provide valuable insights but are invasive and carry risks of biopsy-related complications. This study investigates whether multiparametric magnetic resonance imaging (MRI), including T1 and T2 mapping and diffusion-weighted imaging (DWI), can predict kidney function and the progression of interstitial fibrosis and tubular atrophy (IF/TA) in the early post-transplant period. Methods: A prospective study was conducted at The Hospital of Lithuanian University of Health Sciences Kauno Klinikos from May 2022 to March 2024. Thirty-four patients receiving kidney transplants from deceased donors underwent baseline biopsies and post-transplant MRI scans. Follow-up assessments included kidney function evaluation, biopsies, and MRI scans at three months post-transplant. Results: Significant correlations were observed between MRI parameters and kidney function: T1 and apparent diffusion coefficient (ADC) corticomedullary differentiation (CMD) correlated with eGFR at discharge (r = −0.338, p = 0.05; r = 0.392, p = 0.022, respectively). Linear and logistic regression models demonstrated that post-transplant T1 and ADC CMD values significantly predicted kidney function at discharge. Furthermore, T1 CMD values measured 10–15 days post-transplant predicted IF/TA progression at three months post-kTx, with an area under the curve of 0.802 (95% CI: 0.616–0.987, p = 0.001) and an optimal cut-off value of −149.71 ms. The sensitivity and specificity were 0.818 and 0.273, respectively (Youden’s index = 0.545). T2 mapping was not predictive. Conclusions: This study highlights the potential immediate clinical utility of MRI-derived biomarkers, particularly ADC and T1 CMD, in centers equipped with advanced imaging capabilities as tools for assessing kidney function in the early post-transplant period. With an AUROC of 0.802, T1 CMD demonstrates strong discriminatory power for predicting IF/TA progression early in the post-transplant period.

Background and Aim. This study investigates the ability of T1 mapping to detect microstructural changes in cadaveric kidneys during the early post- transplantation period using magnetic resonance imaging (MRI) (1). The aim is to compare the MRI characteristics of transplanted kidneys (kTx) with different creatinine clearance levels at 7-10 days post-transplantation against those of healthy kidneys. Materials and Methods. With institutional ethics approval, we conducted a prospective study at the Hospital of the Lithuanian University of Health Sciences, Kaunas Clinics, involving 34 kidney transplant recipients and a control group of 30 healthy individuals. MRI scans were performed using a 3T Siemens Skyra scanner (Table 1). Image analysis was conducted by radiologists and a nephrologist using Parametric MRI v1.2.31-b software (Figure 1). Graft function was classified as immediate (IGF), slow (SGF), or delayed (DGF) based on the classification by Isaac E. Hall et al. (2). Clinical and laboratory data are presented in Table 2. [...].

Background / Objective This study investigates the microstructural changes in deceased donors kidneys post-transplantation by The Magnetic Resonance Imaging (MRI). The aim is to compare the MRI of transplanted kidneys (kTx) 7-10 days post-transplantation with healthy native kidneys (control group). Methods A prospective study was conducted at the Hospital of Lithuanian University of Health Sciences Kaunas Clinics. MRIs were performed on 34 kTx and 30 control group kidneys using a 3T Siemens Skyra scanner. Parametric MRI v1.2.31-b was used for T1, T2 Map, and Apparent Diffusion Coefficient (ADC) analyses. Two regions, the cortex and medulla, were defined for kidneys. Measurements were averaged across two observers, and corticomedullary difference (CMD) was calculated. Clinical and laboratory data were collected, and statistical analysis was performed using IBM SPSS Statistics version 29. Results The results showed a decrease in CMD on the T1 kTx map (140.55 SD 67.74 ms and 541.57 SD 217.54 ms, p<0.001), primarily due to a significantly lower T1 relaxation time (rt) in the medulla of kTx (1710.50 SD 231.5 ms and 2068.27 SD 286.93 ms, p<0.001). The T1 cortex rt was similar between groups (1569.95 SD 212.05 vs 1526.70 SD 116.00, p=0.243). The T2 map of kTx showed significantly longer rt in both cortical and medullar regions, (79.1 SD 11.55 ms vs 72.41 SD 10.55 ms, p=0.003) and (78.80 SD 10.03 ms vs 63.60 SD 10.56 ms, p<0.001), resulting in a significant decrease in CMD (0.3 SD 4.93 ms and 8.81 SD 3.82 ms, p<0.001). The ADC of kTx showed significantly reduced cortical values (1927.53 SD 236.67 x 10-6 mm2/s vs 2037.78 SD 73.48 x 10-6 mm2/s, p=0.01) and significantly increased medullar values (1884.66 SD 159.17 x 10-6 mm2/s vs 1730.36 SD 69.69 x 10-6 mm2/s p<0.001). The ADC CMD of kTx was significantly lower than in the control group (42.87 SD 101.34 x 10-6 mm2/s vs 307.41 SD 59.14 x 10-6 mm2/s, p<0.001). Conclusions According to the T2 map, kTx experience ischemia-reperfusion syndrome-induced edema. The cortex of the kTx is well perfused, which we presume is the reason the T1 map is similar to healthy kidneys. However, the relaxation time is significantly shorter in the medulla of kTx, possibly due to reduced blood flow in the peritubular capillaries or reduced urine production. Different ADC values in kTx are indicative of ongoing cell swelling and capillary leakage in the acute phase.

Due to the shortage of donors, living donation is particularly encouraged in kidney transplantation. Transplantation of an incompatible living donor blood type is associated with comparative graft function and moderately higher mortality as compared to ABO compatible kidney transplantation. The main methods of preparation for a kidney transplantation from an incompatible blood group living donor are described and published in the literature. In the Hospital of Lithuanian University of Health Sciences, Kaunas Clinics, ABO incompatible kidney transplantation was started in August 2023. Although the transplantation was successful, we encountered some treatment challenges during the preparation process, which are not described in most of the relevant articles. In this presentation we will share our experiences with a double filtration plasmapheresis as compared to an antigen-specific immunoadsorption. We will also demonstrate an unexpected increase in anti-A1 titre after administration of intravenous immunoglobulin. We hope that our experiences and lessons will be of practical value for other kidney transplant centres.

Introduction: With an ageing population and shortages of organs from deceased donors, more transplantation centers are using kidneys from expanded criteria donors (ExCDK). ExCDK exhibits worse graft survival and higher rejection rates. Aim: To compare structural changes of transplanted kidneys (kTx) from ExCDK and nonExCDK using magnetic resonance imaging (MRI) and time-zero biopsy. Method: Following ethics committee approval, we conducted a prospective study at the Hospital of Lithuanian University of Health Sciences Kaunas Clinics. We performed MRIs of transplanted kidneys using a 3T Siemens Skyra scanner (Table 1) for 34 recipients 7-10 days post-kTx. Radiologists and a nephrologist scored the MRI images. Parametric Magnetic Resonance Imaging v1.2.31-b was used for T1, T2 Map, and apparent diffusion coefficient (ADC) analysis. The interclass correlation coefficient between investigators was 0.96, with measurements averaged across two observers. Time-zero kTx biopsy was evaluated according to Banff-2019 criteria. We compared structural changes assessed by MRI and biopsy between ExCDK and NExCDK. Clinical and laboratory data were collected (Table 2) and analysed using IBM SPSS Statistics version 29. Results: Recipients were categorized into ExCDK (n=20) and NExCDK (n=14). Differences in T1 maps relaxation times for the cortex (1591.122 [1429.06-1743.21] ms vs. 1618.27 [1568.35- 1731.59] ms, p=0.359), for medulla (1778.91 [1584.78-1860.65] ms vs. 1793.90 [1723.73- 1887.05] ms, p=0.341), and cortico-medullar differentiation (CMD) (-143.06 [60.51] ms vs. - 146.56 [74.05] ms, p=0.539) were not significant. T2 maps and ADC sequences showed no significant differences. Zero-time biopsy data were similar. Conclusion: The study found no significant structural differences in transplanted kidneys from ExCDK compared to NExCDK as evaluated by MRI and zero-time biopsy.

Introduction: Kidney transplantation from a deceased donor involves potentially deleterious processes impacting kidney microstructure and function. The magnetic resonance imaging (MRI) and histological evaluation of the transplanted kidney (kTx) have been used to explore associations with graft function and fibrosis. Our study combines kTx biopsies performed after kTx blood supply recovery with MRI conducted 7-10 days post-transplantation, providing an initial understanding of the underlying processes.

Aim: To assess the relationship between structural changes in the kTx, evaluated by MRI and protocol biopsy, and early graft function.

Method: Following approval from the ethics committee, we conducted a prospective study at the Hospital of Lithuanian University of Health Sciences Kaunas Clinics. We performed MRIs of transplanted kidney using a 3T Siemens Skyra scanner (parameters in Table 1) for 34 recipients 7-10 days after successful kTx. Radiologists and a nephrologist scored the MRI images. We employed Parametric Magnetic Resonance Imaging v1.2.31-b for T1, T2 Map, and apparent diffusion coefficient (ADC) for kTx image analysis. Two regions were defined for kTx: cortex and medulla, with the manual placement of regions of interest. The interclass correlation coefficient between investigators was 0.96 for all images. Measurements were averaged across two observers, and mean and standard deviations were calculated. The derived corticomedullary difference (CMD) was also calculated. The kTx biopsy performed during the transplantation was evaluated according to the Banff-2019 criteria. We evaluated early graft function using the classification proposed by Isaac E. Hall and co-authors: immediate, slow, and delayed graft function (IGF, SGF, DGF). Clinical and laboratory data were collected and are presented in Table 2. Statistical analysis was performed using IBM SPSS Statistics version 29.

Results: Recipients were categorized into two groups: IGF (n=20) and SGF/DGF (n=14). We found no differences in T1 and T2 relaxation times, ADC and histological data analysis between IGF and SGF/DGF groups. However, we found a negative correlation between CMD in T1 and the measured glomerular filtration rate (mGFR) on the discharge day (r = -0.383, p = 0.025). Further analysis using univariate linear regression demonstrated a significant negative association between CMD in T1 and mGFR (β coefficient = -0.126, 95% CI [-0.240 to -0.013], p = 0.03). Additionally, CMD in ADC showed a significant positive association with mGFR (β coefficient = 0.095, 95% CI [0.015 - 0.176], p=0.022). Even after adjusting for potentially relevant confounders (such as cold ischemic time), CMD in T1 and ADC remained significant predictors.

Conclusions:

1. Structural differences in MRI and biopsy data were not found between the immediate and deteriorative graft function groups.

2. CMD in T1 and the ADC map showed a significant correlation to mGFR and thereby may serve as potential predictors of early graft function.

Immunotherapy treatment with checkpoint inhibitors (ICIs) has led to a breakthrough in the treatment of oncological diseases. Despite its clinical effectiveness, this treatment differs from others, such as cytotoxic chemotherapy, in that it causes immune-related adverse events. This type of toxicity can affect any organ or organ system of the body. We present a literature review and a rare clinical case from our clinical practice, in which a patient with metastatic clear cell renal carcinoma was treated with a single dose of dual checkpoint blockade (cytotoxic T-lymphocyte-4 (CTLA-4) and programmed death-1 (PD-1)) and simultaneously diagnosed with colitis, hepatitis, and nephritis. After early immunosuppressive treatment with the glucocorticoids, complete organ function recovery was achieved. The follow-up revealed a sustained complete response lasting more than a year.