An Integrated Approach Using HLAMatchmaker and Pirche II for Epitopic Matching in Pediatric Kidney Transplant-A Romanian Single-Center Study

(1) Background: Renal transplantation (KT) is the most efficient treatment for chronic kidney disease among pediatric patients. Antigenic matching and epitopic load should be the main criteria for choosing a renal graft in pediatric transplantation. Our study aims to compare the integration of new histocompatibility predictive algorithms with classical human leukocyte antigen (HLA) matching regarding different types of pediatric renal transplants. (2) Methods: We categorized our cohort of pediatric patients depending on their risk level, type of donor and type of transplantation, delving into discussions surrounding their mismatching values in relation to both the human leukocyte antigen Matchmaker software (versions 4.0. and 3.1.) and the most recent version of the predicted indirectly identifiable HLA epitopes (PIRCHE) II score. (3) Results: We determined that the higher the antigen mismatch, the higher the epitopic load for both algorithms. The HLAMatchmaker algorithm reveals a noticeable difference in eplet load between living and deceased donors, whereas PIRCHE II does not show the same distinction. Dialysis recipients have a higher count of eplet mismatches, which demonstrates a significant difference according to the transplantation type. Our results are similar to those of four similar studies available in the current literature. (4) Conclusions: We suggest that an integrated data approach employing PIRCHE II and HLAMatchmaker algorithms better predicts histocompatibility in KT than classical HLA matching.

Association between Human Leukocyte Antigen and End-Stage Renal Disease in Patients from Transylvania, Romania

End-stage renal disease (ESRD) is the final stage of chronic kidney disease. This study explored the association between human leukocyte antigen (HLA) and ESRD. The interaction between genetic and environmental factors may also play a role in the development of ESRD. The study included 2392 ESRD patients who were awaiting renal transplantation. Blood samples were genotyped by SSOP and SSP-PCR methods. Multivariate logistic regression analysis showed that HLA-A*11 (p = 0.027), HLA-A*34 (p = 0.017), HLA-A*69 (p = 0.012), HLA-B*41 (p < 0.001), HLA-B*50 (p = 0.004), HLA-DRB1*10 (p = 0.027), and HLA-DRB1*14 (p = 0.004) were positively associated with ESRD (OR > 1); HLA-DRB1*07 (p < 0.001), HLA-DRB1*08 (p = 0.005), and HLA-DRB1*13 (p < 0.001) were protective against ESRD (OR < 1); and the three-locus haplotype HLA-A*02-B*41-DRB1*03, containing one susceptible allele, was strongly associated with ESRD (p < 0.001, OR = 3.15). In conclusion, this retrospective analysis of HLA typing in patients with ESRD of various etiologies suggests that molecular data on the HLA polymorphism should be collected in order to identify high-risk ESRD patients and to improve graft survival after kidney transplantation.

The immunologically high-risk kidney recipient in the early post-COVID-19 period. To do or not to do? A case report

Kidney transplantation is nowadays the treatment of choice for end-stage kidney disease (ESKD), and it is the most performed organ transplantation. During the COVID-19 pandemic, kidney-transplant recipients appeared to be at higher risk of morbidity and mortality due to severe forms of illness. The result was a decrease in the number of solid organs transplants worldwide, with patients' reduced chance of receiving transplants. The best timing for surgery after COVID-19 infection is still controversial since most of the available data come from study periods with zero or low prevalence of vaccination and COVID-19 variants with high mortality rates. The American Society of Anesthesiologists (ASA) and the Anesthesia Patient Safety Foundation (APSF) Joint Statement on Elective Surgery/Procedures and Anesthesia for Patients after COVID-19 Infection states that elective surgery should be delayed for 7 weeks after a SARS-CoV-2 infection in unvaccinated patients while making no clear statement for vaccinated ones, or those which have already been infected with the virus. Kidney transplant, as opposed to tissue transplant, is not an elective surgery, so the question raised is whether to do it or not. We present the case of a hyper-immunized 47-year-old male patient with end-stage chronic kidney disease who received a second kidney transplant, despite having a mild SARS-COV 2 infection just 2 weeks before his transplantation surgery.

The Use of Machine Learning Algorithms and the Mass Spectrometry Lipidomic Profile of Serum for the Evaluation of Tacrolimus Exposure and Toxicity in Kidney Transplant Recipients

Tacrolimus has a narrow therapeutic window; a whole-blood trough target concentration of between 5 and 8 ng/mL is considered a safe level for stable kidney transplant recipients. Tacrolimus serum levels must be closely monitored to obtain a balance between maximizing efficacy and minimizing dose-related toxic effects. Currently, there is no specific tacrolimus toxicity biomarker except a graft biopsy. Our study aimed to identify specific serum metabolites correlated with tacrolinemia levels using serum high-precision liquid chromatography–mass spectrometry and standard laboratory evaluation. Three machine learning algorithms were used (Naïve Bayes, logistic regression, and Random Forest) in 19 patients with high tacrolinemia (8 ng/mL) and 23 patients with low tacrolinemia (5 ng/mL). Using a selected panel of five lipid metabolites (phosphatidylserine, phosphatidylglycerol, phosphatidylethanolamine, arachidyl palmitoleate, and ceramide), Mg2+, and uric acid, all three machine learning algorithms yielded excellent classification accuracies between the two groups. The highest classification accuracy was obtained by Naïve Bayes, with an area under the curve of 0.799 and a classification accuracy of 0.756. Our results show that using our identified five lipid metabolites combined with Mg2+ and uric acid serum levels may provide a novel tool for diagnosing tacrolimus toxicity in kidney transplant recipients. Further validation with targeted MS and biopsy-proven TAC toxicity is needed.

Favipiravir in Kidney Transplant Recipients With COVID-19: A Romanian Case Series

Background

Favipiravir (FPV) is an orally administrable antiviral drug that selectively inhibits RNA-dependent RNA polymerase and has been repurposed for COVID-19 treatment. There is limited information on the use of FPV in kidney transplant recipients (KTx), who often have multiple comorbidities and run a higher risk for death from COVID-19.

Methods

We retrospectively reviewed all KTx at our institution who got sick with COVID-19 between March 1, 2020, and May 31, 2021, and who received FPV (loading dose of 1800 mg × 2 on day 1, maintenance dose 2  ×  800 mg/d for 5-14 days) as part of their COVID treatment. We analyzed demographics, clinical course, laboratory data, management, and outcome.

Results

Nine KTx with COVID-19 received FPV; all were hospitalized. The median age was 52 years (range, 32-60 years), and women were predominant (77.7%). Eight KTx had pulmonary involvement on chest radiograph. On admission 1 patient had mild, 5 had moderate, 2 had severe, and 1 had critical disease. Leukopenia and increased creatinine were universally noted. Three patients had disease progression under treatment. Seven patients (77.7%) required additional oxygen, and 4 (57.1%) needed intensive care unit admission. Three KTx died, resulting in an overall mortality of 33.3%. Survivors did not show increased transaminases or creatinine during or after FPV treatment; leukocytes, neutrophils, and platelets improved on discharge compared with admission values.

Conclusions

FPV appears well tolerated by KTx with COVID-19, but its clinical benefit remains unclear. Larger analyses are needed.

The Perspectives of Biomarkers in Predicting the Survival of the Renal Graft

Kidney transplantation (KT) is currently the elective approach for patients with end-stage renal disease. Although it is a safe choice for these patients, the early complications can lead to graft dysfunction. One of the most redoubtable complications is delayed graft function (DGF), having no specific treatment. The effects of DGF on the graft survival are large enough to justify the formulation of specific biological protocols. Therefore, discovering biomarkers of acute impairment in renal transplanted patients is required. Creatinine is a poor marker to establish the kidney injury. Estimated glomerular filtration rate together with creatinine is ready to approximately measure the kidney function. Different serum and urine proteins are being studied as possible predictive biomarkers for delayed graft function. This review will concentrate on recent and existing research which provide insight concerning the contribution of some molecules for the estimation and evaluation of graft function after kidney transplantation. Further studies examining various aspects of DGF after KT are urgently needed to address a hitherto less-known clinical question.

Comparing the First and Second Wave of COVID-19 in Kidney Transplant Recipients: An East-European Perspective

Background

The present study examined whether patient characteristics, management, and outcome of kidney transplant recipients (KTx) with COVID-19 changed in the second versus the first pandemic wave.

Methods

We reviewed all available data (demographics, medical history, comorbidities, therapeutic interventions, and outcome) on our KTx with COVID-19 during the first wave (March–September 2020, n = 33) and the second wave (October 2020–February 2021, n = 149) of the COVID-19 pandemic.

Results

One hundred eighty-two out of our 1,503 KTx in active follow-up got COVID-19 during 12-month period, corresponding to a prevalence of 12.1%. No difference was found in age, gender distribution, comorbidities, body mass index, or baseline immunosuppression between the 2 COVID-19 waves. Bilateral COVID pneumonia was more frequent during the first wave. More KTx were managed as outpatients during the second wave (15 vs. 39%, p < 0.01). Calcineurin inhibitors were more sparingly reduced during the second wave, whereas antimetabolites were similarly reduced (91 vs. 86, p = ns). Admission to intensive care units was comparable between the first (27%) and second waves (23%). During the first wave, 8 out of 9 patients (89%) requiring intensive care died, whereas the mortality of the ICU patients in the second wave was 68% (23 deaths) (p = 0.2). The overall mortality was 24% during the first wave and 16% during the second wave (p = 0.21), while in-hospital mortality was identical between the CO­VID-19 waves (27%). Increasing age and poor allograft function were significant predictors of mortality.

Conclusions

Most patient characteristics and outcome were comparable between the first 2 COVID-19 waves. More KTx were managed as outpatients without an overall negative impact on outcome.

COVID-19 after kidney transplantation: Early outcomes and renal function following antiviral treatment

Objectives

The lack of effective treatments for coronavirus disease 2019 (COVID-19) has mandated the repurposing of several drugs, including antiretrovirals and remdesivir (RDV). These compounds may induce acute kidney injury and are not recommended in patients with poor renal function, such as kidney transplant (KTx) recipients.

Methods

The records of 42 KTx recipients with COVID-19 were reviewed. Some of them were receiving antiretrovirals (n = 10) or RDV (n = 8) as part of COVID-19 management. Most patients were male (71%) and their median age was 52 years. The median glomerular filtration rate in these patients was 56 ml/min. Regarding disease severity, 36% had mild disease, 19% had moderate disease, 31% had severe disease, and 12% had critical disease. Subgroups, i.e., patients receiving antiretrovirals, RDV, or no antivirals, were comparable in terms of patient age, comorbidities, and immunosuppression.

Results

Seven patients (16.6%) died during hospitalization. Acute kidney injury was found in 24% of KTx recipients at admission. Upon discharge, estimated glomerular filtration rate (eGFR) increased in 32% and decreased in 39% of the KTx recipients compared with the admission rate. The decrease was more prevalent in the RDV group (80%) compared with KTx recipients without any antiviral treatment (29%) (p <  0.05). Most patients (62%) returned to baseline eGFR values within 1 month of discharge. The proportion was similar between the patients receiving antiviral treatment and those not receiving this treatment.

Conclusions

KTx recipients run a high risk of COVID-19-related renal impairment. Antivirals appear to be safe for use without major risks for kidney injury.

Difficulties in diagnosing HIV-associated nephropathy in kidney transplanted patients. The role of ultrasound and CEUS

A 62-year-old woman who underwent kidney transplantation in 2014 was diagnosed with HIV infection in 2018. Grey scale and Doppler ultrasound evaluation revealed a normal aspect of the allograft. Contrast-enhanced ultrasound detected a quick cortical contrast uptake followed by a rapid cortical wash-out. This behavior was interpreted as a sign of inflammation. Ten months after ultrasound evaluation the graft presented severe disfunction and the patient was reintroduced into the hemodialysis program.

Angle grinder as surgical tool for incarcerated penoscrotal steel ring

Penile strangulation with concomitant scrotal entrapment by a steel ring is an extremely rare urological emergency that requires immediate intervention. Any delay may lead to irreversible complications. Metal rings increase penile engorgement and are usually associated with an attempt to improve sexual pleasure or to maintain a prolonged erection. The removal of steel rings can be challenging and may require a multidisciplinary approach. We present a unique case report of an 18-year-old male with a penoscrotal steel ring retained for 24 hours that was safely removed using an angle grinder as a surgical tool.

Contrast-enhanced ultrasonography in the initial evaluation of the kidney graft function: a pilot study

AIM

Our study aimed to assess the usefulness of contrast-enhanced ultrasound (CEUS) in the initial evaluation of the graft function.

MATERIALS AND METHOD

A cross-sectional study was conducted in the early postoperative period on patients with kidney transplantation, between September 2017 to November 2018. Two groups of patients were investigated; delayed graft function (DGF) and early graft function (EGF). All patients were examined by grey scale, Doppler ultrasound and CEUS.

RESULTS

Nineteen patients, aged from 23 to 64 years (mean age 50 years), 7 in the DGF group and 12 in the EGF group were evaluated. The resistive index (RI) show significantly higher values in the DGF group at the level of upper interlobar artery (p=0.025) and medium interlobar artery (p=0.02). The CEUS investigation shows a greater region of interest (ROI) area (p=0.02) and lower values for wash-out area under the curve (WoAUC) (p=0.047) and respectively wash-in and wash-out area under the curve (WiWoAUC) (p=0.031) for the DGF group. The quality of fit (QoF) proved lower in the DGF group either for evaluation of global graft (p=0.012), cortex (p=0.025), or medulla (p=0.009).A significant relationship among all patients was found between the glomerular filtration rate (GFR) [ml/min] and the renal artery fall time (FT) [s] (p=0.012), WoAUC [a.u.] (p=0.03), and WiWoAUC [a.u.] (p=0.024). The arterial QoF [%] was associated with the arterial ROI area (p=0.048).

CONCLUSIONS

Intensity CEUS parameters WoAUC and WiWoAUC may be useful to diagnose and follow-up grafts with delayed function. Additional studies on larger cohorts are required for the recommendation of CEUS as a routine evaluation of the transplanted kidney.

Renal Tumors in Young Adults: Is Preoperative Computer Tomography Imaging Suggestive for the Nature of the Tumors?

Renal cell carcinoma (RCC) accounts for 2–3% of all adult malignant neoplasms and is even rarer in patients under 45 years old. Clear-cell carcinoma represents most of the pathological subtypes. Our study aimed to investigate the association between preoperative computer tomography imagistic evaluation and histopathological diagnosis of renal tumors in young adults. Patients younger than 45 years old with renal tumors who were referred for medical treatment at the Clinical Institute of Urology and Renal Transplantation Cluj-Napoca from 2012 to 2019 were considered eligible for the study. Medical charts were retrospectively reviewed, and patients with complete data regarding preoperative diagnostic, histopathological evaluation, and follow-up data, regardless of gender, were included in the study. Sixteen patients younger than 45 years fulfilled all the inclusion criteria and were evaluated. With two exceptions, the evaluated patients were in a T1 and T2 stage, with no vascular invasion or of the adjacent organs. Two-thirds of our patients had a clear-cell renal cell carcinoma. None of our patients fitted in the low complexity surgery category of the R.E.N.A.L. Nephrometry Score and 37.5% of them benefited from partial nephrectomy. Half of the suppositions made based on imaging were concordant with the histopathology report. Fifteen of the patients showed no recurrence during the respective follow-up interval. Computer tomography imaging reports showed on our sample a higher concordance with the histopathological report in the more common subtypes (namely Renal Clear Cell RCC), with typical appearances.

Shear-Wave Elastography Variability Analysis and Relation with Kidney Allograft Dysfunction: A Single-Center Study

Shear-wave elastography (SWE) showed the absence or presence of significant differences among stable kidney allograft function and allograft dysfunction. We evaluated the variability of kidney allograft stiffness in relation to allograft dysfunction, respectively, in terms of a correlation of stiffness with patients' characteristics. A single-center prospective study on patients who had undergone renal transplantation was conducted between October 2017 and November 2018. Patients were clinically classified as having a stable allograft function or allograft dysfunction. SWE examinations performed by the same radiologist with a LOGIQ E9 were evaluated. Ten measurements were done for Young's modulus (kPa) at the level of allograft cortex and another ten at the level of medulla. Eighty-three SWE examinations from 63 patients, 69 stable allografts, and 14 allografts with dysfunction were included in the analysis. The intra-examinations stiffness showed high variability, with the quantile covariation coefficient ranging from 2.21% to 45.04%. The inter-examinations stiffness showed heterogeneity (from 28.66% to 42.38%). The kidney allograft cortex stiffness showed significantly higher values in cases with dysfunction (median = 28.70 kPa, interquartile range (IQR) = (25.68-31.98) kPa) as compared to those with stable function (median = 20.99 kPa, interquartile range = (16.08-27.68) kPa; p-value = 0.0142). Allograft tissue stiffness (both cortex and medulla) was significantly negatively correlated with body mass index (-0.44, p-value < 0.0001 for allograft cortex and -0.42, p-value = 0.0001 for allograft medulla), and positively correlated with Proteinuria/Creatinuria ratio (0.33, p-value = 0.0021 for allograft cortex and 0.28, p-value = 0.0105 for allograft medulla) but remained statistically significant only in cases with stable function. The cortical tissue stiffness proved significantly higher values for patients with allograft dysfunction as compared to patients with stable function, but to evolve as an additional tool for the evaluation of patients with a kidney transplant and to change the clinical practice, more extensive studies are needed.

Ex-vivo perfusion machines in kidney transplantation. The significance of the resistivity index

Introduction

With a growing shortage of organs for transplantation, finding ways of increasing the donor organ pool remains of utmost importance. Perfusion machines (PM) have been proven to enhance the potential for kidney transplants to function sooner, last longer, giving patients the opportunity for a better life quality.

Objective

The aim of this study is to evaluate the relation between the resistance index provided by the PM, the postoperative resistance index measured by Doppler ultrasound and the initial graft outcome.

Material and method

Between January 2012-December 2012, clinical data obtained from 82 consecutive renal transplants from brain death donors (BDD) which underwent PM maintenance were analyzed in a transversal study. Prior transplantation we recorded the solution temperature, filtration rate and the resistance index provided by PM. After the surgical intervention, each patient had standard follow-up. Doppler ultrasound resistivity index (RI) was recorded on the first postoperative day.

Results

Out of 115 renal transplants, 98 (85.21%) were performed with grafts from BDD. The PM was used for 82 renal grafts. The Doppler resistance index in relation to the resistance index shows a highly statistical correlation by linear regression (R=0.813, p<0.0001). Primary graft function was recorded in 74 patients (90.24%) and it was highly statistically significant correlated with the resistance index measured by PM. Out of 8 patients with primary non-function, 6 patients recovered with normal graft function at one year.

Conclusion

The resistivity index recorded by the life-port machine is correlated with the vascular resistivity index measured by Doppler ultrasound and thus it may predicts the primary graft outcome.