Progression of Portal Hypertension in Acute Cellular Rejection After Liver Transplantation.

OBJECTIVES: This study was designed to investigate the frequency of computed tomography features indicating progression of portal hypertension and their clinical relevance in patients who experienced acute cellular rejection after liver transplantation. MATERIALS AND METHODS: This retrospective study included 141 patients with pathologically diagnosed acute cellular rejection following liver transplant. Patients were divided into early and late rejection groups according to the time of diagnosis. Two radiologists analyzed the interval changes in spleen size and variceal engorgement on computed tomography images obtained at the times of surgery and biopsy. Aggravation of splenomegaly and variceal engorgement were considered computed tomography features associated with the progression of portal hypertension. Clinical outcomes, including responses to treatment and graft survival, were compared between patients with and without these features. RESULTS: The frequency of progression of portal hypertension was 31.9% and did not differ significantly in patients who experienced early (30.8% [28/91]) and late (34.0% [17/50]) rejection (P = .694). In the late rejection group, computed tomography features indicating progression of portal hypertension were significantly associated with poor response to treatment (P = .033). Graft survival in both the early and late rejection groups did not differ significantly in patients with and without progression of portal hypertension. CONCLUSIONS: Computed tomography features suggesting the progression of portal hypertension were encountered in about one-third of patients who experienced acute cellular rejection after liver transplant. Progression of portal hypertension was significantly related to poor response to treatment in the late rejection group.

Obesity and dyslipidemia predict cardiac allograft vasculopathy and graft loss in children and adolescents post-heart transplant: A PHTS multi-institutional analysis.

BACKGROUND: Obesity and dyslipidemia afflict children of all ages. We explored the prevalence of obesity and dyslipidemia in pediatric heart transplant (HT) recipients and its effects on cardiac allograft vasculopathy (CAV) and survival. METHODS: This study included primary HT recipients (≤18 years) transplanted between 01/1996 and 12/2018 included in the Pediatric Heart Transplant Society database. Obesity was categorized according to WHO/CDC guidelines and dyslipidemia according to the National Cholesterol Education Program. Kaplan-Meier analyses for CAV and graft loss stratified for BMI and lipid panels were generated and risk factors identified using multivariate analyses. RESULTS: Among 6291 HT patients (median age [range] at HT = 4.3 [0.6-12.8] years; 45% Female; 68% White), 56% had a normal BMI at HT. Obese patients at HT had an increased risk for graft loss (HR 1.19, 95% CI 1.01-1.4, p = .04). Poor total cholesterol (TC), LDL-C, and TG were associated with the risk of both CAV (HR 1.79, p < .0001; HR 1.65, p = .0015; HR 1.53, p < .0001, respectively) and graft loss (HR 1.58, p = .0008; HR 1.22, p = .04; HR 1.43, p = .0007, respectively). CONCLUSIONS: Pediatric patients who are obese at the time of HT and dyslipidemic at 1 year post-HT are at an increased risk for CAV and graft loss. Preventative interventions may reduce morbidity and mortality among this cohort.

Thrombotic microangiopathy after kidney transplantation: Analysis of the Brazilian Atypical Hemolytic Uremic Syndrome cohort.

BACKGROUND: Atypical Hemolytic Uremic Syndrome (aHUS) is an ultra-rare disease that potentially leads to kidney graft failure due to ongoing Thrombotic Microangiopathy (TMA). The aim was evaluating the frequency of TMA after kidney transplantation in patients with aHUS in a Brazilian cohort stratified by the use of the specific complement-inhibitor eculizumab. METHODS: This was a multicenter retrospective cohort study including kidney transplant patients diagnosed with aHUS. We collected data from 118 transplant centers in Brazil concerning aHUS transplanted patients between 01/01/2007 and 12/31/2019. Patients were stratified into three groups: no use of eculizumab (No Eculizumab Group), use of eculizumab for treatment of after transplantation TMA (Therapeutic Group), and use of eculizumab for prophylaxis of aHUS recurrence (Prophylactic Group). RESULTS: Thirty-eight patients with aHUS who received kidney transplantation were enrolled in the study. Patients' mean age was 30 years (24-40), and the majority of participants was women (63% of cases). In the No Eculizumab Group (n = 11), there was a 91% graft loss due to the TMA. The hazard ratio of TMA graft loss was 0.07 [0.01-0.55], p = 0.012 in the eculizumab Prophylactic Group and 0.04 [0.00-0.28], p = 0.002 in the eculizumab Therapeutic Group. CONCLUSION: The TMA graft loss in the absence of a specific complement-inhibitor was higher among the Brazilian cohort of kidney transplant patients. This finding reinforces the need of eculizumab use for treatment of aHUS kidney transplant patients. Cost optimization analysis and the early access to C5 inhibitors are suggested, especially in low-medium income countries.

Impact of Hyponatremia after Renal Transplantation on Decline of Renal Function, Graft Loss and Patient Survival: A Prospective Cohort Study.

BACKGROUND: Hyponatremia is one of the most common electrolyte disorders observed in hospitalized and ambulatory patients. Hyponatremia is associated with increased falls, fractures, prolonged hospitalisation and mortality. The clinical importance of hyponatremia in the renal transplant field is not well established, so the aim of this study was to determine the relationships between hyponatremia and mortality as main outcome and renal function decline and graft loss as secondary outcome among a prospective cohort of renal transplant recipients. METHODS: This prospective cohort study included 1315 patients between 1 May 2008 and 31 December 2014. Hyponatremia was defined as sodium concentration below 136 mmol/L at 6 months after transplantation. The main endpoint was mortality. A secondary composite endpoint was also defined as: rapid decline in renal function (≥5 mL/min/1.73 m2 drop of the eGFR/year), graft loss or mortality. RESULTS: Mean sodium was 140 ± 3.08 mmol/L. 97 patients displayed hyponatremia with a mean of 132.9 ± 3.05 mmol/L. Hyponatremia at 6 months after transplantation was associated neither with mortality (HR: 1.02; p = 0.97, 95% CI: 0.47-2.19), nor with the composite outcome defined as rapid decline in renal function, graft loss or mortality (logrank test p = 0.9). CONCLUSIONS: Hyponatremia 6 months after transplantation is not associated with mortality in kidney allograft patients.

Thrombotic Microangiopathy, Antibody-Mediated Rejection, and Posterior Reversible Leukoencephalopathy Syndrome in a Liver Transplant Recipient: Interplay Between COVID-19 and Its Treatment Modalities.

The present COVID-19 pandemic is a cause for concern among solid-organ transplant recipients, who are generally at high risk for infection and for whom infection with COVID-19 carries additional risks for complications and mortality that are higher than the COVID-19-associated risks for the general population. We report the case of a liver transplant recipient who presented with COVID-19 and multiple complications. A 39-year-old woman with a liver transplant was diagnosed with COVID-19 within the first week after transplant surgery. Mycophenolate was withheld, and interferon ß was administered for management of COVID-19. She developed thrombotic thrombocytopenic purpura, acute antibody-mediated rejection, and posterior reversible leukoencephalopathy syndrome during hospitalization. All of these complications may be related to COVID-19 or its management modalities. We considered 3 possible causes for thrombotic thrombocytopenic purpura in this patient: the COVID-19 infection itself, immunosuppression treatment with cyclosporine, and treatment with interferon ß. Immunosuppression reduction and interferon treatment may result in antibody-mediated rejection. COVID-19, thrombotic thrombocytopenic purpura, and cyclosporine may play a combined role in the development of posterior reversible leukoencephalopathy syndrome. In conclusion, thrombotic thrombocytopenic purpura, antibody-mediated rejection, and posterior reversible leukoencephalopathy syndrome may represent a continuum of 3 thrombotic microangiopathy conditions fostered by interplay between the COVID-19 infection and the treatment modalities for COVID-19 management in this patient.

Case Report: Convalescent Plasma Achieves SARS-CoV-2 Viral Clearance in a Patient With Persistently High Viral Replication Over 8 Weeks Due to Severe Combined Immunodeficiency (SCID) and Graft Failure.

We describe the unique disease course and cure of SARS-CoV-2 infection in a patient with SCID and graft failure. In absence of a humoral immune response, viral clearance was only achieved after transfusion of convalescent plasma. This observation underscores the necessity of the humoral immune response for SARS-CoV-2 clearance.

Delayed graft function and rejection are risk factors for cytomegalovirus breakthrough infection in kidney transplant recipients.

Breakthrough cytomegalovirus (CMV) disease during valganciclovir prophylaxis is rare but may cause significant morbidity and even mortality. In order to identify patients at increased risk the incidence of CMV disease was studied in a large population of renal transplant recipients who underwent a kidney transplantation in the Radboud University Medical Center between 2004 and 2015 (n = 1300). CMV disease occurred in 31/1300 patients. Multivariate binary linear regression analysis showed that delayed graft function (DGF) (p = 0.018) and rejection (p = 0.001) significantly and independently increased the risk of CMV disease, whereas CMV status did not. Valganciclovir prophylaxis was prescribed to 281/1300 (21.6%) high-risk patients (defined as CMV IgG-seronegative recipients receiving a kidney from a CMV IgG-seropositive donor (D+/R-)). Of these 281 patients, 51 suffered from DGF (18%). The incidence of breakthrough CMV disease in D + /R- patients with DGF was much higher than in those with immediate function (6/51 (11.8%) vs 2/230, (0.9%), p = 0.0006 Fisher's exact test), despite valganciclovir prophylaxis. This higher incidence of CMV disease could not be explained by a higher incidence of rejection (and associated anti-rejection treatment) in patients with DGF. D + /R- patients with DGF are at increased risk of developing CMV disease despite valganciclovir prophylaxis. These findings suggest that underexposure to ganciclovir occurs in patients with DGF. Prospective studies evaluating the added value of therapeutic drug monitoring to achieve target ganciclovir concentrations in patients with DGF are needed.

Hyperbaric oxygen therapy to prevent central airway stenosis after lung transplantation.

BACKGROUND: Central airway stenosis (CAS) is a severe airway complication after lung transplantation associated with bronchial ischemia and necrosis. We sought to determine whether hyperbaric oxygen therapy (HBOT), an established treatment for tissue ischemia, attenuates post-transplant bronchial injury. METHODS: We performed a randomized, controlled trial comparing usual care with HBOT (2 atm absolute for 2 hours × 20 sessions) in subjects with extensive airway necrosis 4 weeks after transplantation. Endobronchial biopsies were collected at 4, 7, and 10 weeks after transplantation for a quantitative polymerase chain reaction. Coprimary outcomes were incidence of airway stenting and acute cellular rejection (ACR) at 1 year. RESULTS: The trial was stopped after enrolling 20 subjects (n = 10 per group) after a pre-planned interim analysis showed no difference between usual care and HBOT groups in stenting (both 40%), ACR (70% and 40%, respectively), or CAS (40% and 60%, respectively). Time to first stent placement (median [interquartile range]) was significantly shorter in the HBOT group (150 [73-150] vs 186 [167-206] days, p < 0.05). HIF gene expression was significantly increased in donor tissues at 4, 7, and 10 weeks after transplantation but was not altered by HBOT. Subjects who developed CAS or required stenting had significantly higher HMOX1 and VEGFA expression at 4 weeks (both p < 0.05). Subjects who developed ACR had significant FLT1, TIE2, and KDR expression at 4 weeks (all p < 0.05). CONCLUSIONS: Incidence of CAS is high after severe, established airway necrosis after transplantation. HBOT does not reduce CAS severity or stenting. Elevated HMOX1 and VEGFA expressions appear to associate with airway complications.

Suppressive effects of vitamin C-treated induced-regulatory T cells on heart allograft rejection under vitamin C-deficient or -sufficient conditions.

Foxp3 stability of vitamin C-treated induced-regulatory T cells (V-iTregs) is superior to that of conventional iTregs (C-iTregs). However, the role of V-iTregs in allograft rejection under vitamin C-deficient conditions, such as those seen in humans, remains unclear. We aimed to elucidate the role of vitamin C treatment on generation and maintenance of iTregs from gulo knockout (Gulo-KO) mice as well as wild type (WT) mice, and in vitro and in vivo suppressive effects of V-iTregs on heart allograft rejection in either Gulo-KO or WT recipient mice. Conversion efficiency of iTregs was similar between C- and V-iTregs in both WT and Gulo-KO mice. V-iTregs from WT or Gulo-KO mice showed better in vitro Foxp3 stability than C-iTregs, although there was no difference between WT V-iTregs and Gulo-KO V-iTregs. Furthermore, V-iTregs from WT or Gulo-KO mice suppressed in vitro T cell proliferation better than C-iTregs. Heterotrophic heart transplantation from BALB/c mice to WT or vitamin C-deficient Gulo-KO C57BL/6J mice was performed following adoptive transfer of C- or V-iTregs. V-iTregs as well as C-iTregs prolonged heart allograft survival in WT and Gulo-KO mice. However, there was no difference between the C- and V-iTreg groups. Supplementation of low- or high-dose vitamin C did not induce significant changes in heart allograft survival in Gulo-KO recipients that had received V-iTregs. In conclusion, V-iTregs do not exert better suppressive effects on heart allograft survival than C-iTregs in either WT or vitamin C-deficient recipients.

Everolimus Alleviates Renal Allograft Interstitial Fibrosis by Inhibiting Epithelial-to-Mesenchymal Transition Not Only via Inducing Autophagy but Also via Stabilizing IκB-α.

Chronic allograft dysfunction (CAD) is the major cause of late graft loss in long-term renal transplantation. In our previous study, we found that epithelial-mesenchymal transition (EMT) is a significant event in the progression of renal allograft tubulointerstitial fibrosis, and impaired autophagic flux plays a critical role in renal allograft fibrosis. Everolimus (EVR) has been reported to be widely used to prevent the progression of organ fibrosis and graft rejection. However, the pharmacological mechanism of EVR in kidney transplantation remains to be determined. We used CAD rat model and the human kidney 2 (HK2) cell line treated with tumor necrosis factor-α (TNF-α) and EVR to examine the role of EVR on TNF-α-induced EMT and transplanted renal interstitial fibrosis. Here, we found that EVR could attenuate the progression of EMT and renal allograft interstitial fibrosis, and also activate autophagy in vivo. To explore the mechanism behind it, we detected the relationship among EVR, autophagy level, and TNF-α-induced EMT in HK2 cells. Our results showed that autophagy was upregulated upon mTOR pathway inhibition by EVR, which could significantly reduce expression of TNF-α-induced EMT. However, the inhibition of EVR on TNF-α-induced EMT was partly reversed following the addition of autophagy inhibitor chloroquine. In addition, we found that TNF-α activated EMT through protein kinase B (Akt) as well as nuclear factor kappa B (NF-κB) pathway according to the RNA sequencing, and EVR's effect on the EMT was only associated with IκB-α stabilization instead of the Akt pathway. Together, our findings suggest that EVR may retard impaired autophagic flux and block NF-κB pathway activation, and thereby prevent progression of TNF-α-induced EMT and renal allograft interstitial fibrosis.

Non-obstructive coronary angiogram findings prior to kidney transplantation do not predict post-transplant cardiac events.

BACKGROUND: This study aimed to determine the risk factors associated with cardiac events 1 year after transplant in kidney transplant recipients (KTRs). MATERIAL AND METHODS: We analyzed the incidence of cardiac events in all KTRs transplanted at our center between 01/2000 and 12/2016, who had non-obstructive cardiac catheterization findings at their pre-transplant evaluation. RESULTS: We identified 141 patients with non-obstructive pre-transplant cardiac catheterization. 83 patients (59%) had cardiac events 1 year after the kidney transplant during a mean follow-up of 7.3 ± 5.3 years. Multivariate Cox regression analysis determined dialysis ≥ 1 year (HR = 2.27, 95% Cl 1.41 - 3.67, p = 0.001), body mass index (BMI) ≥ 35 kg/m2 at time of transplant (HR = 2.24, 95% Cl 1.43 - 3.52, p = 0.0004), tacrolimus trough ≥ 7 ng/mL at 1 year post-transplant (HR = 4.24, 95% Cl 1.95 - 9.22, p = 0.0003), and HBA1-c ≥ 7% at 1 year post-transplant (HR = 1.71, 95% Cl 1.09 - 2.70, p = 0.02) as significant predictors of cardiac events 1 year post-transplant. In unadjusted Kaplan-Meier analysis, any cardiac event post-transplant was associated with a significant risk of death or graft loss (p = 0.02). CONCLUSION: Dialysis duration, morbid obesity, diabetes control, and tacrolimus levels may represent modifiable risk factors to reduce cardiac events in kidney transplant recipients with non-obstructive cardiac catheterization findings at the time of transplant.

Kidney allograft recipients, immunosuppression, and coronavirus disease-2019: a report of consecutive cases from a New York City transplant center.

BACKGROUND: Kidney graft recipients receiving immunosuppressive therapy may be at heightened risk for coronavirus disease 2019 (Covid-19) and adverse outcomes. It is therefore important to characterize the clinical course and outcome of Covid-19 in this population and identify safe therapeutic strategies. METHODS: We performed a retrospective chart review of 73 adult kidney graft recipients evaluated for Covid-19 from 13 March to 20 April 2020. Primary outcomes included recovery from symptoms, acute kidney injury, graft failure and case fatality rate. RESULTS: Of the 73 patients screened, 54 tested positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-39 with moderate to severe symptoms requiring hospital admission and 15 with mild symptoms managed in the ambulatory setting. Hospitalized patients were more likely to be male, of Hispanic ethnicity and to have cardiovascular disease. In the hospitalized group, tacrolimus dosage was reduced in 46% of patients and mycophenolate mofetil (MMF) therapy was stopped in 61% of patients. None of the ambulatory patients had tacrolimus reduction or discontinuation of MMF. Azithromycin or doxycycline was prescribed at a similar rate among hospitalized and ambulatory patients (38% versus 40%). Hydroxychloroquine was prescribed in 79% of hospitalized patients. Graft failure requiring hemodialysis occurred in 3 of 39 hospitalized patients (8%) and 7 patients died, resulting in a case fatality rate of 13% among Covid-19-positive patients and 18% among hospitalized Covid-19-positive patients. CONCLUSIONS: Data from our study suggest that a strategy of systematic triage to outpatient or inpatient care, early management of concurrent bacterial infections and judicious adjustment of immunosuppressive drugs rather than cessation is feasible in kidney transplant recipients with Covid-19.

Clinical Course, Imaging Features, and Outcomes of COVID-19 in Kidney Transplant Recipients.

Coronavirus disease 2019 (COVID-19) is a novel and highly contagious disease caused by Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Older adults and patients with comorbidities and immunosuppressive conditions may experience severe signs and symptoms that can lead to death. This case series assesses the clinical course, imaging features, and outcomes for 12 patients with COVID-19 and a history of kidney transplantation. Patients were evaluated for symptoms, laboratory data, imaging findings, and outcomes from February 2020 to April 2020. Fever, cough, and dyspnea were the most common clinical symptoms, noted in 75% (nine/12), 75% (nine/12), and 41.7% (five/12) of the patients, respectively. Most of the patients had a normal white blood cell count, while 33.3% (four/12) had leukopenia and 8.3% (one/12) had leukocytosis. A combination of consolidation and ground glass opacity was the most predominant (75%) pattern of lung involvement on computed tomography (CT). Eight patients died of severe COVID-19 pneumonia and acute respiratory distress syndrome and four were discharged. All recovered cases had a unilateral peripheral pattern of involvement limited to only one zone on initial chest CT. It seems that CT imaging has an important role in predicting COVID-19 outcomes for solid organ transplant recipients. Future studies with long-term follow up and more cases are needed to elucidate COVID-19 diagnosis, outcome, and management strategies for these patients.

Risk factors for recurrent autoimmune liver diseases after liver transplantation: A meta-analysis.

BACKGROUND: Autoimmune liver disease (ALD) is a chronic liver disease caused by immune dysfunction in the body. However, no causative or curative medical treatment with proven efficacy exists to cure ALDs, and liver transplantation (LT) remains the only effective treatment available. However, the problem of recurrence of ALDs (rALDs) still remains after LT, which seriously affects the survival rate of the patients. Therefore, clinicians need to be aware of the risk factors affecting rALDs after LT. Therefore, this meta-analysis aims to define the risk factors for rALDs, which include the recurrence of primary biliary cirrhosis, primary sclerosing cholangitis and autoimmune hepatitis. METHODS: A systematic search in Pubmed, Embase, Cochrane library and Web of Science databases was performed from 1980 to 2019. The inclusion criteria were risk factors for developing rALDs after LT. However, case series, case reports, reviews, meta-analysis and studies only including human immunodeficiency virus cases, children, and pregnant patients were excluded. RESULTS: The electronic database search yielded 1728 results. Sixty-three retrospective cohort studies met the inclusion criteria and 13 were included in the meta-analysis. The final cohort included 5077 patients, and among them, 21.96% developed rALDs. Colectomy before LT, HR 0.59 (95% confidence interval [CI]: 0.37-0.96), cholangiocarcinoma, HR 3.42 (95% CI: 1.88-6.21), multiple episodes of acute cellular rejection, HR 2.07 (95% CI: 1.27-3.37), model for end-stage liver disease score, HR 1.05 (95% CI: 1.02-1.08), use of mycophenolate mofetil, HR 1.46 (95% CI: 1.00-2.12) and the use of cyclosporin A, HR 0.69 (95% CI: 0.49-0.97) were associated with the risk of rprimary sclerosing cholangitis. In addition, the use of tacrolimus, HR 1.73 (95% CI: 1.00-2.99) and cyclosporin A, HR 0.59 (95% CI: 0.39-0.88) were associated with the risk of rALD. CONCLUSIONS: Multiple risk factors for rALDs were identified, such as colectomy before LT, cholangiocacinoma, multiple episodes of acute cellular rejection, model for end-stage liver disease score, and especially the use of mycophenolate mofetil, cyclosporin A and tacrolimus.

Isolated thrombotic microangiopathy of the small intestine in a patient with atypical hemolytic uremic syndrome - a case report.

BACKGROUND: Atypical hemolytic uremic syndrome (aHUS) is a rare disease characterized by systemic thrombotic microangiopathy (TMA) reflected by hemolysis, anemia, thrombocytopenia and systemic organ injury. The optimal management of aHUS-patients when undergoing kidney transplantation to prevent recurrence in the allograft is eculizumab, an approved recombinant antibody targeting human complement component C5. CASE PRESENTATION: A 39 year-old woman presented with severe abdominal pain, diarrhea and emesis for 3 days. In her past medical history she had experienced an episode of aHUS leading to end stage renal disease (ESRD) in 2007 and a genetic workup revealed a heterozygous mutation in the membrane cofactor protein gene. In 2014 she underwent cadaveric kidney transplantation. Four years later she had to go back on hemodialysis due to allograft failure following a severe systemic cytomegalovirus infection resulting in transplant failure. At presentation she still received calcineurin-inhibitor therapy and reported subfebrile temperatures and pain projecting over the transplant prior to the current symptoms. A contrast enhanced CT-scan of the abdomen revealed inflammatory wall thickening of the small intestine. Diagnostic endoscopy discovered fresh blood in the small intestine without a clear source of bleeding. Histopathology of the small intestine biopsies showed severe thrombotic microangiopathy. Of note, the patient persistently had no signs of systemic hemolysis. Since the TMA of the small intestine was most likely due to aHUS, eculizumab treatment was initiated which abolished the symptoms. CONCLUSION: Here we report a patient with thrombotic microangiopathy with predominant manifestation in a single organ, the small intestine, due to aHUS with absence of systemic signs and symptoms. aHUS patients usually require a secondary trigger for the disease to manifest. In this case, the trigger may be attributed to the dysfunctional renal transplant, which was subsequently explanted. Histology of the explanted kidney showed severe inflammation due to purulent nephritis and signs of cellular rejection. After nephrectomy, we continued eculizumab therapy until the patient completely recovered. No signs of TMA recurred after discontinuation of eculizumab, further supporting the concept of the renal transplant as the main trigger of TMA of the small intestine in our patient.