Orchestrating the Impact of KIR/HLA Interactions on Kidney Transplant.

This study examines the interplay between human leukocyte antigen (HLA) compatibility and killer-cell immunoglobulin-like receptor (KIR) genotypes in influencing kidney transplantation outcomes. Understanding these interactions is crucial for improving graft survival and minimizing rejection risks. We evaluated 84 kidney transplant recipients, dividing them into two groups based on post-transplant outcomes: there were 68 with stable graft function (SGF) and 16 who experienced chronic rejection (CR). Patients were selected based on specific inclusion criteria. HLA mismatches (Class I: HLA-A, -B; Class II: HLA-DR) and KIR genotypes were determined using standard genotyping techniques. Statistical analyses, including logistic regression, were performed to correlate these factors with transplant outcomes. Significant age differences were observed, with younger patients more likely to experience graft rejection, while no significant gender-based differences were noted. A significant correlation was found between Class II mismatches and increased rejection rates, highlighting the importance of HLA-DR compatibility. Further analysis revealed that certain inhibitory KIRs, such as KIR3DL1, were associated with favorable outcomes, suggesting a protective role against graft rejection. These findings were corroborated by evaluating serum creatinine levels over multiple years, serving as a biomarker for renal function post transplant. This study underscores the critical need for meticulous HLA matching and the consideration of KIR genotypes in pre-transplant evaluations to enhance graft survival and minimize rejection risks. Integrating these genetic factors into routine clinical assessments could significantly improve personalized transplant medicine strategies, ultimately enhancing patient outcomes. Further research is needed to explore the underlying mechanisms and validate these findings in larger, diverse populations.

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.

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 CO-VID-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.

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.

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.

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.