The time-dependent changes in serum immunoglobulin after kidney transplantation and its association with infection.

Introduction: Kidney transplant recipients often experience significant alterations in their immune system, which can lead to increased susceptibility to infections. This study aimed to analyze time-dependent changes in serum immunoglobulin and complement levels and determine the risk factors associated with infection. Methods: A retrospective analysis of serum samples from 192 kidney transplant recipients who received transplantations between August 2016 and December 2019 was conducted. The serum samples were obtained at preoperative baseline (T0), postoperative 2 weeks (T1), 3 months (T2), and 1 year (T3). The levels of serum C3, C4, IgG, IgA, and IgM were measured to evaluate immune status over time. Results: The analysis revealed significant decreases in IgG and IgA levels at T1. This period was associated with the highest occurrence of hypogammaglobulinemia (HGG) and hypocomplementemia (HCC), as well as an increased incidence of severe infection requiring hospitalization and graft-related viral infections. Using a time-dependent Cox proportional hazards model adjusted for time-varying confounders, HGG was significantly associated with an increased risk of infection requiring hospitalization (HR, 1.895; 95% CI: 1.871-1.920, P-value<0.001) and graft-related viral infection (HR, 1.152; 95% CI: 1.144-1.160, P-value<0.001). Discussion: The findings suggest that monitoring serum immunoglobulin levels post-transplant provides valuable insights into the degree of immunosuppression. Hypogammaglobulinemia during the early post-transplant period emerges as a critical risk factor for infection, indicating that serum immunoglobulins could serve as feasible biomarkers for assessing infection risk in kidney transplant recipients.

Association of BKV viremia and nephropathy with adverse alloimmune outcomes in kidney transplant recipients.

BACKGROUND: Immunosuppression reduction for BK polyoma virus (BKV) must be balanced against risk of adverse alloimmune outcomes. We sought to characterize risk of alloimmune events after BKV within context of HLA-DR/DQ molecular mismatch (mMM) risk score. METHODS: This single-center study evaluated 460 kidney transplant patients on tacrolimus-mycophenolate-prednisone from 2010-2021. BKV status was classified at 6-months post-transplant as "BKV" or "no BKV" in landmark analysis. Primary outcome was T-cell mediated rejection (TCMR). Secondary outcomes included all-cause graft failure (ACGF), death-censored graft failure (DCGF), de novo donor specific antibody (dnDSA), and antibody-mediated rejection (ABMR). Predictors of outcomes were assessed in Cox proportional hazards models including BKV status and alloimmune risk defined by recipient age and molecular mismatch (RAMM) groups. RESULTS: At 6-months post-transplant, 72 patients had BKV and 388 had no BKV. TCMR occurred in 86 recipients, including 27.8% with BKV and 17% with no BKV (p = .05). TCMR risk was increased in recipients with BKV (HR 1.90, (95% CI 1.14, 3.17); p = .01) and high vs. low-risk RAMM group risk (HR 2.26 (95% CI 1.02, 4.98); p = .02) in multivariable analyses; but not HLA serological MM in sensitivity analysis. Recipients with BKV experienced increased dnDSA in univariable analysis, and there was no association with ABMR, DCGF, or ACGF. CONCLUSIONS: Recipients with BKV had increased risk of TCMR independent of induction immunosuppression and conventional alloimmune risk measures. Recipients with high-risk RAMM experienced increased TCMR risk. Future studies on optimizing immunosuppression for BKV should explore nuanced risk stratification and may consider novel measures of alloimmune risk.

Metastatic Merkel Cell Carcinoma After Simultaneous Pancreas-Kidney Transplantation: Fatal Outcomes.

Merkel cell carcinoma (MCC) is a rare, highly aggressive cutaneous malignancy. Immunosuppression increases the risk of MCC and is associated with poor prognosis. Organ transplant recipients (OTR) have worse overall survival (OS) than patients with immunosuppression due to other causes. Treating MCC after organ transplantation is challenging, as checkpoint inhibitor immunotherapy, the standard of care for treating MCC, increases the risk of transplant rejection. This paper reviews the cases of two simultaneous pancreas-kidney transplant (SPKT) recipients with MCC and explores the role of immunosuppression in the development of MCC. Immunosuppression was discontinued and checkpoint inhibitor therapy was initiated in the first patient and considered by the second patient. In both cases, treatment failed, and the patients died shortly after developing metastatic MCC. These cases illustrate the need for improved multidisciplinary treatment regimens for MCC in OTRs. J Drugs Dermatol. 2024;23(5):376-377.     doi:10.36849/JDD.8234  .

Disseminated Talaromyces marneffei infection initially presenting as cutaneous and subcutaneous lesion in an HIV-Negative renal transplant recipient: a case report and literature review.

BACKGROUND: The incidence of Talaromyces marneffei (T. marneffei) infection has increased in recent years with the development of organ transplantation and the widespread use of immunosuppressive agents. However, the lack of clinical suspicion leading to delay or misdiagnosis is an important reason for the high mortality rate in non-human immunodeficiency virus (HIV) and non-endemic population. Herein, we report a case of disseminated T. marneffei infection in a non-HIV and non-endemic recipient after renal transplant, who initially presented with skin rashes and subcutaneous nodules and developed gastrointestinal bleeding. CASE PRESENTATION: We describe a 54-year-old renal transplantation recipient presented with scattered rashes, subcutaneous nodules and ulcerations on the head, face, abdomen, and right upper limb. The HIV antibody test was negative. The patient had no obvious symptoms such as fever, cough, etc. Histopathological result of the skin lesion sites showed chronic suppurative inflammation with a large number of fungal spores. Subsequent fungal culture suggested T. marneffei infection. Amphotericin B deoxycholate was given for antifungal treatment, and there was no deterioration in the parameters of liver and kidney function. Unfortunately, the patient was soon diagnosed with gastrointestinal bleeding, gastrointestinal perforation and acute peritonitis. Then he rapidly developed multiple organ dysfunction syndrome and abandoned treatment. CONCLUSIONS: The risk of fatal gastrointestinal bleeding can be significantly increased in kidney transplant patients with T. marneffei infection because of the long-term side effects of post-transplant medications. Strengthening clinical awareness and using mNGS or mass spectrometry technologies to improve the detection rate and early diagnosis of T. marneffei are crucial for clinical treatment in non-HIV and non-endemic population.

Neutralizing antibody responses and cellular responses against SARS-CoV-2 Omicron subvariants after mRNA SARS-CoV-2 vaccination in kidney transplant recipients.

Although the mRNA SARS-CoV-2 vaccine has improved the mortality rate in the general population, its efficacy against rapidly mutating virus strains, especially in kidney transplant recipients, remains unclear. We examined the anti-SARS-CoV-2 spike protein IgG antibody and neutralizing antibody titers and cellular immunity against B.1.1, BA.1, and BA.5 antigens in 73 uninfected kidney recipients and 16 uninfected healthy controls who received three doses of an mRNA SARS-CoV-2 vaccine. The IgG antibody titers were significantly lower in recipients than in healthy controls. Similarly, neutralizing antibody titers against three viral variants were significantly lower in recipients. When the virus was mutated, the neutralizing antibody titers decreased significantly in both groups. In cellular immunity analysis, the number of spike-specific CD8 + non-naïve T cells against three variants significantly decreased in recipients. Conversely, the frequency of spike-specific Th2 CD4 + T-cells in recipients was higher than that in healthy controls. Nineteen recipients and six healthy controls also received a bivalent omicron-containing booster vaccine, leading to increase IgG and neutralizing antibody titers in both groups. After that, eleven recipients and five healthy controls received XBB.1.5 monovalent vaccines, increasing the neutralizing antibody titers against not only XBB.1.5, but also EG.5.1 and BA.2.86 antigens in kidney recipients. Although kidney recipients did not gain sufficient immunity against Omicron BA.5 with the third dose of vaccine, humoral response against mutant SARS-CoV-2 lineages significantly increased after bivalent Omicron-containing booster vaccine and the XBB.1.5 monovalent vaccine. Therefore, it is important for kidney recipients to continue to administer updated vaccines.

Clinical outcomes and risk factors for mortality in recipients with carbapenem-resistant gram-negative bacilli infections after kidney transplantation treated with ceftazidime-avibactam: a retrospective study.

Background: Ceftazidime-avibactam is a treatment option for carbapenem-resistant gram-negative bacilli (CR-GNB) infections. However, the risk factors associated with ceftazidime-avibactam (CAZ-AVI) treatment failure in kidney transplant (KT) recipients and the need for CAZ-AVI-based combination therapy remain unclear. Methods: From June 2019 to December 2023, a retrospective observational study of KT recipients with CR-GNB infection treated with CAZ-AVI was conducted, with the primary outcome being 30-day mortality and secondary outcomes being clinical cure, microbiological cure, and safety. Risk factors for 30-day mortality and clinical failure were also investigated. Results: A total of 81 KT recipients treated with CAZ-AVI were included in this study. Forty recipients (49.4%) received CAZ-AVI monotherapy, with a 30-day mortality of 22.2%. The clinical cure and microbiological cure rates of CAZ/AVI therapy were 72.8% and 66.7%, respectively. CAZ-AVI alone or in combination with other medications had no effect on clinical cure or 30-day mortality. Multivariate logistic regression analysis revealed that a higher Acute Physiology and Chronic Health Evaluation (APACHE) II score (odds ratio [OR]: 4.517; 95% confidence interval [CI]: 1.397-14.607; P = 0.012) was an independent risk factor for 30-day mortality. Clinical cure was positively associated with the administration of CAZ-AVI within 48 hours of infection onset (OR: 11.009; 95% CI: 1.344-90.197; P=0.025) and negatively associated with higher APACHE II scores (OR: 0.700; 95% CI: 0.555-0.882; P=0.002). Four (4.9%) recipients experienced recurrence within 90 days after the initial infection, 3 (3.7%) recipients experienced CAZ-AVI-related adverse events, and no CAZ-AVI resistance was identified. Conclusion: CAZ-AVI is an effective medication for treating CR-GNB infections following kidney transplantation, even as monotherapy. Optimization of CAZ/AVI therapy (used within 48 hours of infection onset) is positively associated with potential clinical benefit. Further larger-scale studies are needed to validate these findings.

Contrast-enhanced US in Renal Transplant Complications: Overview and Imaging Features.

Renal transplant is the first-line treatment of end-stage renal disease. The increasing number of transplants performed every year has led to a larger population of transplant patients. Complications may arise during the perioperative and postoperative periods, and imaging plays a key role in this scenario. Contrast-enhanced US (CEUS) is a safe tool that adds additional value to US. Contrast agents are usually administered intravenously, but urinary tract anatomy and complications such as stenosis or leak can be studied using intracavitary administration of contrast agents. Assessment of the graft and iliac vessels with CEUS is particularly helpful in identifying vascular and parenchymal complications, such as arterial or venous thrombosis and stenosis, acute tubular injury, or cortical necrosis, which can lead to graft loss. Furthermore, infectious and malignant graft involvement can be accurately studied with CEUS, which can help in detection of renal abscesses and in the differentiation between benign and malignant disease. CEUS is also useful in interventional procedures, helping to guide percutaneous aspiration of collections with better delimitation of the graft boundaries and to guide renal graft biopsies by avoiding avascular areas. Potential postprocedural vascular complications, such as pseudoaneurysm, arteriovenous fistula, or active bleeding, are identified with CEUS. In addition, newer quantification tools such as CEUS perfusion are promising, but further studies are needed to approve its use for clinical purposes. ©RSNA, 2024 Supplemental material is available for this article.

Pitfalls in Valganciclovir Prophylaxis Dose Adjustment Based on Renal Function in Kidney Transplant Recipients.

Valganciclovir (VGC) is administered as prophylaxis to kidney transplant recipients (KTR) CMV donor (D)+/recipient (R)- and CMV R+ after thymoglobulin-induction (R+/TG). Although VGC dose adjustments based on renal function are recommended, there is paucity of real-life data on VGC dosing and associations with clinical outcomes. This is a retrospective Swiss Transplant Cohort Study-embedded observational study, including all adult D+/R- and R+/TG KTR between 2010 and 2020, who received prophylaxis with VGC. The primary objective was to describe the proportion of inappropriately (under- or over-) dosed VGC week-entries. Secondary objectives included breakthrough clinically significant CMV infection (csCMVi) and potential associations between breakthrough-csCMVi and cytopenias with VGC dosing. Among 178 KTR, 131 (73.6%) patients had ≥2 week-entries for the longitudinal data of interest and were included in the outcome analysis, with 1,032 VGC dose week-entries. Overall, 460/1,032 (44.6%) were appropriately dosed, while 234/1,032 (22.7%) and 338/1,032 (32.8%) were under- and over-dosed, respectively. Nineteen (14.5%) patients had a breakthrough-csCMVi, without any associations identified with VCG dosing (p = 0.44). Unlike other cytopenias, a significant association between VGC overdosing and lymphopenia (OR 5.27, 95% CI 1.71-16.22, p = 0.004) was shown. VGC prophylaxis in KTR is frequently inappropriately dosed, albeit without meaningful clinical associations, neither in terms of efficacy nor safety.

Surgical complications and technical failure of simultaneous pancreas-kidney transplantation: A 22-year experience from a single center.

Simultaneous pancreas-kidney transplantation (SPKT) is the best treatment for selected individuals with type 1 diabetes mellitus and end-stage renal disease. Despite advances in surgical techniques, donor and recipient selection, and immunosuppressive therapies, SPKT remains a complex procedure with associated surgical complications and adverse consequences. We conducted a retrospective study that included 263 SPKT procedures performed between May 2000, and December 2022. A total of 65 patients (25%) required at least one relaparotomy, resulting in an all-cause relaparotomy rate of 2.04 events per 100 in-hospital days. Lower donor body mass index was identified as an independent factor associated with reoperation (OR .815; 95% CI:  .725-.917, p = .001). Technical failure (TF) occurred in 9.9% of cases, primarily attributed to pancreas graft thrombosis, intra-abdominal infections, bleeding, and anastomotic leaks. Independent predictors of TF at 90 days included donor age above 36 years (HR 2.513; 95% CI 1.162-5.434), previous peritoneal dialysis (HR 2.503; 95% CI 1.149-5.451), and specific pancreas graft reinterventions. The findings highlight the importance of carefully considering donor and recipient factors in SPKT. The incidence of TF in our study population aligns with the recent series. Continuous efforts should focus on identifying and mitigating potential risk factors to enhance SPKT outcomes, thereby reducing post-transplant complications.

Rictor/mTORC2 signalling contributes to renal vascular endothelial-to-mesenchymal transition and renal allograft interstitial fibrosis by regulating BNIP3-mediated mitophagy.

BACKGROUND: Renal allograft interstitial fibrosis/tubular atrophy (IF/TA) constitutes the principal histopathological characteristic of chronic allograft dysfunction (CAD) in kidney-transplanted patients. While renal vascular endothelial-mesenchymal transition (EndMT) has been verified as an important contributing factor to IF/TA in CAD patients, its underlying mechanisms remain obscure. Through single-cell transcriptomic analysis, we identified Rictor as a potential pivotal mediator for EndMT. This investigation sought to elucidate the role of Rictor/mTORC2 signalling in the pathogenesis of renal allograft interstitial fibrosis and the associated mechanisms. METHODS: The influence of the Rictor/mTOR2 pathway on renal vascular EndMT and renal allograft fibrosis was investigated by cell experiments and Rictor depletion in renal allogeneic transplantation mice models. Subsequently, a series of assays were conducted to explore the underlying mechanisms of the enhanced mitophagy and the ameliorated EndMT resulting from Rictor knockout. RESULTS: Our findings revealed a significant activation of the Rictor/mTORC2 signalling in CAD patients and allogeneic kidney transplanted mice. The suppression of Rictor/mTORC2 signalling alleviated TNFα-induced EndMT in HUVECs. Moreover, Rictor knockout in endothelial cells remarkably ameliorated renal vascular EndMT and allograft interstitial fibrosis in allogeneic kidney transplanted mice. Mechanistically, Rictor knockout resulted in an augmented BNIP3-mediated mitophagy in endothelial cells. Furthermore, Rictor/mTORC2 facilitated the MARCH5-mediated degradation of BNIP3 at the K130 site through K48-linked ubiquitination, thereby regulating mitophagy activity. Subsequent experiments also demonstrated that BNIP3 knockdown nearly reversed the enhanced mitophagy and mitigated EndMT and allograft interstitial fibrosis induced by Rictor knockout. CONCLUSIONS: Consequently, our study underscores Rictor/mTORC2 signalling as a critical mediator of renal vascular EndMT and allograft interstitial fibrosis progression, exerting its impact through regulating BNIP3-mediated mitophagy. This insight unveils a potential therapeutic target for mitigating renal allograft interstitial fibrosis.

Risk factors for Pneumocystis jirovecii pneumonia after kidney transplantation: A systematic review and meta-analysis.

BACKGROUND AND OBJECTIVE: Pneumocystis jirovecii pneumonia (PJP), an opportunistic infection, often leads to an increase in hospitalization time and mortality rates in kidney transplant (KT) recipients. However, the risk factors associated with PJP in KT recipients remain debatable. Therefore, we conducted this meta-analysis to identify risk factors for PJP, which could potentially help to reduce PJP incidence and improve outcome of KT recipients. METHODS: We systematically retrieved relevant studies in PubMed, EMBASE, and the Cochrane Library up to November 2023. Pooled odds ratios (ORs) or mean differences (MDs) and the corresponding 95% confidence intervals (CIs) were calculated to assess the impact of potential risk factors on the occurrence of PJP. RESULTS: 27 studies including 42383 KT recipients were included. In this meta-analysis, age at transplantation (MD = 3.48; 95% CI = .56-6.41; p = .02), cytomegalovirus (CMV) infection (OR = 4.00; 95% CI = 2.53-6.32; p = .001), BK viremia (OR = 3.38; 95% CI = 1.70-6.71; p = .001), acute rejection (OR = 3.66; 95% CI = 2.44-5.49; p = .001), ABO-incompatibility (OR = 2.51; 95% CI = 1.57-4.01; p = .001), estimated glomerular filtration rate (eGFR) (MD = -14.52; 95% CI = -25.37- (-3.67); p = .009), lymphocyte count (MD = -.54; 95% CI = -.92- (-.16); p = .006) and anti-PJP prophylaxis (OR = .53; 95% CI = .28-.98; p = .04) were significantly associated with PJP occurrence. CONCLUSION: Our findings suggest that transplantation age greater than 50 years old, CMV infection, BK viremia, acute rejection, ABO-incompatibility, decreased eGFR and lymphopenia were risk factors for PJP.

Prediction models for postoperative renal function after living donor nephrectomy: a systematic review.

INTRODUCTION: Living-donor nephrectomy (LDN) is the most valuable source of organs for kidney transplantation worldwide. The current preoperative evaluation of a potential living donor candidate does not take into account formal estimation of postoperative renal function decline after surgery using validated prediction models. The aim of this study was to summarize the available models to predict the mid- to long-term renal function following LDN, aiming to support both clinicians and patients during the decision-making process. EVIDENCE ACQUISITION: A systematic review of the English-language literature was conducted following the principles highlighted by the European Association of Urology (EAU) guidelines and following the PRISMA 2020 recommendations. The protocol was registered in PROSPERO on December 10, 2022 (registration ID: CRD42022380198). In the qualitative analysis we selected the models including only preoperative variables. EVIDENCE SYNTHESIS: After screening and eligibility assessment, six models from six studies met the inclusion criteria. All of them relied on retrospective patient cohorts. According to PROBAST, all studies were evaluated as high risk of bias. The models included different combinations of variables (ranging between two to four), including donor-/kidney-related factors, and preoperative laboratory tests. Donor age was the variable more often included in the models (83%), followed by history of hypertension (17%), Body Mass Index (33%), renal volume adjusted by body weight (33%) and body surface area (33%). There was significant heterogeneity in the model building strategy, the main outcome measures and the model's performance metrics. Three models were externally validated. CONCLUSIONS: Few models using preoperative variables have been developed and externally validated to predict renal function after LDN. As such, the evidence is premature to recommend their use in routine clinical practice. Future research should be focused on the development and validation of user-friendly, robust prediction models, relying on granular large multicenter datasets, to support clinicians and patients during the decision-making process.

Pre-Transplant Calcimimetic Use and Dose Information Improves the Accuracy of Prediction of Tertiary Hyperparathyroidism after Kidney Transplantation: A Retrospective Cohort Study.

Tertiary hyperparathyroidism (THPT) is characterized by elevated parathyroid hormone and serum calcium levels after kidney transplantation (KTx). To ascertain whether pre-transplant calcimimetic use and dose information would improve THPT prediction accuracy, this retrospective cohort study evaluated patients who underwent KTx between 2010 and 2022. The primary outcome was the development of clinically relevant THPT. Logistic regression analysis was used to evaluate pre-transplant calcimimetic use as a determinant of THPT development. Participants were categorized into four groups according to calcimimetic dose, developing two THPT prediction models (with or without calcimimetic information). Continuous net reclassification improvement (CNRI) and integrated discrimination improvement (IDI) were calculated to assess ability to reclassify the degree of THPT risk by adding pre-transplant calcimimetic information. Of the 554 patients, 87 (15.7%) developed THPT, whereas 139 (25.1%) received pre-transplant calcimimetic treatment. Multivariate logistic regression analysis revealed that pre-transplant calcimimetic use was significantly associated with THPT development. Pre-transplant calcimimetic information significantly improved the predicted probability accuracy of THPT (CNRI and IDI were 0.91 [p < 0.001], and 0.09 [p < 0.001], respectively). The THPT prediction model including pre-transplant calcimimetic information as a predictive factor can contribute to the prevention and early treatment of THPT in the era of calcimimetics.

BK Viremia and Viruria Does Not Depend on the Type of Double-J Stent Used During Kidney Transplantation.

OBJECTIVES: BK virus is a major cause of chronic renal allograft failure.Transplant ureteral stent use has been reported as a risk factorfor BK virus infection. Recently, the use of a new type of ureteral stent (Magnetic Black Star) was reported in kidney transplant recipients. The aim ofthis preliminary report was to compare BK virus viremia and viruria occurrence depending on the type of double-J stent (standard versus Magnetic Black Star). MATERIALS AND METHODS: We included all kidney transplants performed in our center from January to December 2022. Each case had double-J stent placement. Indwelling stents were either a 6- or 7-Fr standard double-J stent or a 6-Fr Magnetic Black Star double-J stent. The type of double-J stent was chosen according to the surgeon's preference. A standard BK virus screening protocol was followed during the study period, which consisted of routine polymerase chain reaction examination of plasma and urine samples during monthly follow-ups. RESULTS: We assessed 120 patients without missing data: 92 patients received standard double-J stents and 28 patients received Magnetic Black Star stents. Patients were mostly male in the standard group (70.7%) versus the Magnetic Black Star group (42.9%) (P = .01). ABO- and HLA-incompatible transplant rates were similar in both groups. BK viremia occurrence and BK viruria occurrence were similar between groups at 1 month, 3 months, and 6 months. CONCLUSIONS: This preliminary study showed no differences concerning BKvirus infection depending on the type of double-J stents used during kidney transplant.

Diagnosis and Management of Ureteropelvic Obstruction in Kidney Transplant Recipients and Outcomes of Foley Y-V Pyeloplasty.

OBJECTIVES: To evaluate the etiology and diagnostic tools for ureteropelvic obstruction in kidney transplant recipients, we investigated the short-term and long-term outcomes of Foley Y-V pyeloplasty. MATERIALS AND METHODS: We retrospectively reviewed 10 patients who underwent kidney transplant followed by additional interventions to treat obstructive ureteral pathologies between 2016 and 2020. We enrolled 4 patients who had received intervention to treat ureteropelvic obstruction. For these 4 patients, serum creatinine and estimated glomerular filtration rate levels were recorded at baseline, during the symptomatic period, and long-term. In this single center study, we investigated diagnostic tools and management strategies for ureteropelvic obstruction and assessed performance of Foley Y-V nondismembered pyeloplasty in kidney transplant recipients. RESULTS: Among 4 patients, graft function (assessed by serum creatinine and estimated glomerular filtration rate) worsened significantly (P = .03) in the symptomatic period of ureteropelvic obstruction in all patients; however, graft function levels improved rapidly to levels similar to baseline (P = .07) after Y-V pyeloplasty. In addition, no statistically significant difference was detected between baseline and longterm graft functions afterY-V pyeloplasty in follow-up (P = .28). CONCLUSIONS: Diagnosis and management of ureteropelvic obstruction in kidney transplant recipients are challenging due to rarity and lack of an ideal management algorithm.There is no specific diagnostic tool to discriminate this pathology from other ureteral pathologies; therefore, a regimen of conventional imaging modalities and diuretic renogram combined with endoscopic evaluation is more reliable. Moreover, nondismembered Foley Y-V pyeloplasty is effective and safe for graft function in the short-term and long-term.

Bronchiectasis After Solid-Organ Transplant: A Retrospective Single Center Study.

OBJECTIVES: Bronchiectasis is characterized by abnormal, persistent, and irreversible enlargement of the bronchi. Many etiological factors have been described, but there are limited data on the development of bronchiectasis after organ transplantation. Our study is the first to study evaluate the frequency of bronchiectasis in heart and liver transplants as well as kidney transplants. Our aim is to analyze the frequency of bronchiectasis development after solid-organ transplant and the characteristics of the cases and to evaluate potential relationships. MATERIALS AND METHODS: We retrospectively analyzed data of patients who underwent solid-organ transplant at the Baskent University Faculty of Medicine Hospital through the hospital electronic information system. Demographic, clinical, and laboratory data and thoracic computed tomography scans were evaluated. RESULTS: The study included 468 patients (151 females/317 males). Kidney transplant was performed in 61.5% (n = 207), heart transplant in 20.3% (n = 95), and liver transplant in 18.2% (n = 85) of patients. Development of bronchiectasis was detected in only 13 patients (2.7%). We determined a 13.64-fold risk of developing bronchiectasis in patients with chronic obstructive pulmonary disease and 10.08-fold risk in patients with pneumonia by multivariate regression analyzes, in which all possible risk factors for the development of bronchiectasis after transplant were evaluated. CONCLUSIONS: The pathophysiology of transplantassociated bronchiectasis has not yet been clarified. Underlying diseases, recurrent pulmonary infections, and potential effects from immunosuppressive drugs may contribute to the pathogenesis of bronchiectasis. Further prospective studies are needed to include long-term health outcomes in transplant patients with and without bronchiectasis.

Acute Airway Obstruction: An Unusual Presentation of Posttransplant Lymphoproliferative Disorder in a Renal Transplant Recipient.

Posttransplant lymphoproliferative disorder is a life-threatening complication after solid-organ transplants. In adults, recipients of heart transplants have the highest risk, whereas renal transplant recipients have the lowest risk among all solid-organ transplants. The most common site for posttransplant lymphoproliferative disorders are gastrointestinal tract followed by the graft itself. Airway involvement in posttransplant lymphoproliferative disorder is rarely encountered. We report a case of a 26-year-old renal allograft recipient who presented to the emergency room with airway obstruction necessitating an emergency tracheostomy. Imaging revealed a left tonsillar mass extending into the nasopharynx and retropharyngeal space causing complete oropharyngeal occlusion. Endoscopic biopsy from nasopharyngeal mass showed a diffuse large B-cell lymphoma and was Ebstein-Barr virus positive. Reduction in immunosuppression and treatment with posttransplant lymphoproliferative disorder-1 risk-stratified approach resulted in complete remission.

Effects of Antithymocyte Globulin, Basiliximab, and Induction-Free Treatment in Living Donor Kidney Transplant Recipients on Tacrolimus-Based Immunosuppression.

OBJECTIVES: Induction treatment in renal transplant is associated with better graft survival. However, intensified immunosuppression is known to cause unwanted side effects such as infection and malignancy. Furthermore, the effects of the routine use of immunosuppressants in low-risk kidney transplant recipients are still not clear. In this study, we assessed the first-year safety and efficacy of induction treatment. MATERIALS AND METHODS: We examined first living donor kidney transplant patients who were on tacrolimus based immunosuppression therapy. We formed 3 groups according to the induction status: antithymocyte globulin induction, basiliximab induction, and no induction. We collected outcome data on delayed graft function, graft loss, creatinine levels, estimated glomerular filtration rates, acute rejection episodes, hospitalization episodes, and infection episodes, including cytomegalovirus infection and bacterial infections. RESULTS: We examined a total of 126 patients (age 35 ± 12 years; 65% male). Of them, 25 received antithymocyte globulin, 52 received basiliximab, and 49 did notreceive any induction treatment. We did not observe any statistically significant difference among the 3 groups in terms of acute rejection episodes, delayed graft function, and first-year graft loss. The estimated glomerular filtration rates were similar among the groups. Overall bacterial infectious complications and cytomegalovirus infection showed similar prevalence among all groups. Hospitalization was less common in the induction-free group. CONCLUSIONS: In low-risk patients, induction-free regimens could be associated with a better safety profile without compromising graft survival. Therefore, induction treatment may be disregarded in first living donor transplant patients who receive tacrolimusbased triple immunosuppression treatment.

Diagnosing and Managing Urinary Tract Infections in Kidney Transplant Recipients.

In the article, the authors review antibiotic treatment options for both acute uncomplicated UTI and complicated UTI. In addition, they review alternative regimens which are needed in the setting of drug-resistant pathogens including vancomycin-resistant Enterococcus, -extended-spectrum beta-lactamase-producing Enterobacterales (ESBL-E), carbapenem-resistant Enterobacterales, and carbapenem-resistant Pseudomonas, which are encountered with more frequency.

Donor heart dysfunction and graft survival in liver and kidney transplants-A register-based study from Sweden.

BACKGROUND AND AIM: Stress cardiomyopathy in donors can potentially affect graft function and longevity. This study aims to investigate the association between echocardiographic left ventricular ejection fraction (LVEF) < 50%, and/or the presence of left ventricular regional wall motion abnormalities (RWMA) in organ donors, and short- and long-term liver and kidney graft survival. Our secondary aim was to link graft survival with donor and recipient characteristics. METHODS: All donors considered for liver and kidney donation with echocardiographic records at Sahlgrenska University Hospital between 2006 and 2016 were matched with their recipients through the Scandiatransplant register. The studied outcomes were graft survival, re-transplantation, and recipient death. Kaplan-Meier curves were used to plot time to event. Multivariate Cox-regression was used to test independence. RESULTS: There were 370 liver donors and 312 kidney donors (matched with 458 recipients) with echocardiographic records at Sahlgrenska University Hospital between June 2006 and November 2016. Of patients with LV dysfunction by echocardiography, there were 102 liver- and 72 kidney donors. Univariate survival analyses showed no statistical difference in the short- and long-term graft survival from donors with LV dysfunction compared to donors without. Donor age > 65 years, recipient re-transplantation and recipient liver tumor were predictors of worse outcome in liver transplants (p < .05). Donor age > 65, donor hypertension, recipient re-transplantation, and a recipient diagnosis of diabetes or nephritis/glomerulonephritis had a negative association with graft survival in kidney transplants (p < .05). CONCLUSION: We found no significant association between donor LV dysfunction and short- and long-term graft survival in liver and kidney transplants, suggesting that livers and kidneys from such donors can be safely transplanted.