Subclinical Inflammation and Prothrombotic State in Heart Transplant Recipients: Impact of Cyclosporin Microemulsion vs. Tacrolimus

Intracardiac Thrombus Associated With DeVega Tricuspid Valve Repair Following Heart Transplantation

Intracardiac thrombus is a rare but treatable complication following DeVega tricuspid annuloplasty in the setting of orthotopic heart transplantation. Consistent imaging in the post-transplantation period is therefore essential for early identification and management of thromboembolic complications.

Prevalence and potential relevance of hyperuricemia in pediatric kidney transplant recipients-a CERTAIN registry analysis

BACKGROUND

Asymptomatic hyperuricemia is frequently observed in pediatric kidney transplant recipients; symptomatic hyperuricemia, however, is a rare complication. Only few data are available in this patient population. We, therefore, investigated the prevalence of hyperuricemia and its association with kidney transplant function and blood pressure in a multicenter cohort of pediatric kidney transplant recipients.

METHODS

This is a retrospective, observational multicenter registry study. All pediatric kidney transplant recipients in the CERTAIN database with at least one documented serum uric acid level and a follow-up of 5 years posttransplant were eligible. We identified 151 patients with 395 measurements of serum uric acid. We calculated the prevalence of hyperuricemia, analyzed potential risk factors and clinical consequences such as elevated blood pressure and reduced estimated glomerular filtration rate (eGFR). Statistical analysis was performed using IBM SPSS Statistics 26.

RESULTS

One hundred and ten of 395 (27.8%) serum uric acid levels were above 416 µmol/L (7.0 mg/dL), defined as the upper limit of normal. Univariate analysis showed a significant (p = .026) inverse association of serum uric acid with eGFR overtime. There was no significant association of serum uric acid concentrations with body mass index (z-score), blood pressure (z-score), or sex. No episodes of gout were documented.

CONCLUSION

This study shows that hyperuricemia is present in a considerable number of patients sometime after pediatric kidney transplantation and is associated with lower eGFR. Whether hyperuricemia contributes to faster decline of graft function or to the overall cardiovascular risk of these patients remains to be elucidated.

Cyclosporine-A-Induced Intracranial Thrombotic Complications: Systematic Review and Cases Report

This study reported two cases of intracranial thrombotic events of aplastic anemia (AA) under therapy with cyclosporine-A (CsA) and reviewed both drug-induced cerebral venous thrombosis (CVT) and CsA-related thrombotic events systematically. We searched PubMed Central (PMC) and EMBASE up to Sep 2019 for publications on drug-induced CVT and Cs-A-induced thrombotic events. Medical subject headings and Emtree headings were used with the following keywords: "cyclosporine-A" and "cerebral venous thrombosis OR cerebral vein thrombosis" and "stroke OR Brain Ischemia OR Brain Infarction OR cerebral infarction OR intracerebral hemorrhage OR intracranial hemorrhage." We found that CsA might be a significant risk factor in inducing not only CVT but also cerebral arterial thrombosis in patients with AA.

Cardiopulmonary, biomarkers, and vascular responses to acute hypoxia following cardiac transplantation

Previous studies have suggested good adaptation of cardiac transplant (CTx) recipients to exposure to a high altitude. No studies have investigated the cardiopulmonary and biomarker responses to acute hypoxic challenges following CTx. Thirty-six CTx recipients and 17 age-matched healthy controls (HC) were recruited. Sixteen (16) patients (42%) had cardiac allograft vasculopathy (CAV). Cardiopulmonary responses to maximal and submaximal exercise at 21% O₂ , 20-minutes hypoxia (11.5% O₂ ), and following a 10-minute exposure to 11.5% O₂ using 30% of peak power output were completed. Vascular endothelial growth factor (VEGF), interleukin-6 (IL-6), suppression of tumorigenicity 2 (ST2) were measured at baseline and at peak stress. Endothelial peripheral function was assessed using near-infrared spectroscopy. Compared with HC, CTx presented a lesser O₂ desaturation both at rest (-19.4 ± 6.8 [CTx] vs -24.2 ± 6.0% O₂ [HC], P < 0.05) and following exercise (-23.2 ± 4.9 [CTx] vs -26.2 ± 4.7% O₂ [HC], P < 0.05). CTx patients exhibited a significant decrease in peak oxygen uptake. IL-6 and VEGF levels were significantly higher in CTx recipients in basal conditions but did not change in response to acute stress. CTx patients exhibit a favorable ventilatory and overall response to hypoxic stress. These data provide further insights on the good adaptability of CTx to exposure to high altitude.

Decreased circulating and neutrophil mediated VEGF-A165 release in stable long-term cardiac transplant recipients

Background

Vascular endothelial growth factor (VEGF) may play a role on the allograft remodelling following cardiac transplantation (CTx). We measured the circulating levels of VEGF-A₁₆₅ concomitantly with the proinflammatory (Interleukin-8; IL-8), anti-inflammatory (IL-1 receptor antagonist; IL-1RA) and their release from neutrophils of CTx recipients.

Methods

Eighteen CTx recipients aged 49.6 ± 3.1 years, being transplanted for 145 ± 20 months were age-matched to 35 healthy control (HC) subjects. Concomitantly to plasma assessment, circulating neutrophils were isolated, purified and stimulated by vehicle (PBS), N-formyl-Met-Leu-Phe (fMLP, 10⁻⁷ M), bacterial lipopolysaccharide (LPS, 1 μg/mL), or tumour necrosis factor alpha (TNF-α, 10 ng/mL).

Results

Compared with HC, CTx recipients exhibited a decrease (−80%) in plasmatic levels of VEGF-A₁₆₅ (225 ± 42 (HC) vs 44 ± 10 pg/mL (CTx); (p < 0.001). There were no differences in the levels of IL-8 and IL-1RA. Under basal or stimulated conditions, neutrophils from CTx patients exhibited a marked decrease ranging from −30 to −88% on their capacity to release VEGF-A₁₆₅, IL-8 and IL-1RA upon stimulation.

Conclusions

Long-term CTx recipients exhibit a marked reduction in the circulating levels of VEGF-A₁₆₅, as well as neutrophil-mediated release of VEGF-A₁₆₅, IL-1RA and IL-8 compared to healthy volunteers. The mechanisms and physiological impacts of these findings deserve additional investigations.

Myocyte growth, repair, and oxidative stress following pediatric heart transplantation

Cardiac remodeling is associated with plasma biomarkers of fibrinogenesis, inflammation, and oxidative stress, and upregulation of mitogenic, pro-fibrotic, and apoptotic signaling pathways. Our primary objective was to evaluate biomarker and subcellular myocardial changes in pediatric heart transplant recipients. Fifty-two-week prospective, randomized (tacrolimus, Tac, vs. cyclosporine, CsA), open-label, parallel group study. Serial myocardial biopsies were probed for mitogenic and pro-inflammatory proteins. Plasma biomarkers of oxidative stress (F2α isoprostanes, nitrotyrosine), and inflammation and oxidation (hsCRP and cystatin-C) were measured. Nine of 11 randomized patients completed the study (four Tac, five CsA). Mean levels of F2α isoprostanes, hsCRP, and cystatin-C were maximal at Week 2. Peak activation of all MAP kinases in myocardial tissue was maximal at Week 10; no association was seen with rejection. Cardiac Bax/Bcl-2 levels (index of apoptosis) correlated negatively with F2α isoprostanes at Week 2 (r = -0.88) and with hsCRP at Week 52 (r = -0.67). At Week 52, hsCRP levels correlated positively with molecular indices of cardiac cell growth. We found evidence of systemic and myocardial oxidative damage and inflammation early posttransplant, which may be related to the remodeling process. Further study is needed to better understand the cardiac and systemic repair processes following pediatric heart transplantation.

A role for tissue plasminogen activator in thrombotic thrombocytopenic purpura

Thrombotic thrombocytopenic purpura (TTP) is a life-threatening disease characterized by generalized microvascular occlusion. TTP has been related to severe deficiency of ADAMTS13, an enzyme that cleaves von Willebrand factor multimers into less adhesive molecules. However, ADAMTS13 deficiency correlates poorly with severity of thrombocytopenia or microangiopathic hemolysis, with the frequency of neurologic complications or the response to plasma exchange. Also, some patients with severe hereditary ADAMTS13 deficiency consistently relapse every few weeks, whereas others remain asymptomatic into their forties. Taken together, these findings suggest that an additional element is missing in the pathophysiology of TTP. We postulate that both low ADAMTS13 activity and low tissue-plasminogen activator activity are required to trigger TTP attacks. Tissue-plasminogen activator end product, plasmin, extensively degrades von Willebrand factor, breaking-down the bonds between platelets and the blood vessel wall, so that low tissue-plasminogen activator activity prevents a mechanism similar to that of ADAMTS13. The hypothesis that low tissue-plasminogen activator activity plays an important role in TTP pathogenesis is further substantiated by TTP comorbidity. Problems prevalent in patients with TTP attacks or with long-term TTP remission, including increased body mass index, major depression, cognitive abnormalities, hypertension, and premature death, are somehow associated with low tissue-plasminogen activator activity.

Effect of everolimus on the immunomodulation of the human neutrophil inflammatory response and activation

The primary cause of mortality at 5 years following a cardiac transplantation is the development of atherosclerosis, termed coronary allograft vasculopathy (CAV). This pathology is characterized by diffused intimal hyperplasia and emanates from coronary arterial injuries caused by immune inflammatory cells. Neutrophils play an important role in this inflammatory process; however, their potential participation in the pathogenesis of CAV is poorly understood. Despite their essential contribution to the prevention of graft rejection, immunosuppressive drugs could have detrimental effects owing to their pro-inflammatory activities. Thus, we investigated the impact of different immunosuppressive drugs on the inflammatory response of neutrophils isolated from the blood of healthy volunteers. Under basal conditions, mammalian target of rapamycin (mTOR) inhibitors (sirolimus and everolimus) had the most potent anti-inflammatory effect, decreasing both IL-8 release (≈−80%) and vascular endothelial growth factor (VEGF) release (≈−65%) and preserving the release of the anti-inflammatory cytokine interleukin-1 receptor antagonist (IL-1RA). In TNF-α-treated neutrophils, pre-incubation with everolimus provided the most potent effect, simultaneously reducing the release of both VEGF and IL-8 while doubling the release of IL-1RA. This latter effect of everolimus was maintained even when administered in combination with other immunosuppressive drugs. Sirolimus and everolimus decreased the tumor necrosis factor (TNF)-α-induced adhesion of neutrophils to human endothelial cells and human extracellular matrix. This effect was largely dependent on the ability of these compounds to alter β₂-integrin/CD18 activation. Our results suggest a potential mechanism for the beneficial effect of everolimus in the prevention of CAV in heart transplant recipients.

Selective clinical and immune response of the oligoclonal autoreactive T cells in Omenn patients after cyclosporin A treatment

The immunological hallmark of Omenn syndrome (OS) is the expansion and activation of an oligoclonal population of autoreactive T cells. These cells should be controlled rapidly by immunosuppressive agents, such as cyclosporin A (CsA), to avoid tissue infiltration and to improve the general outcome of the patients. Here we studied the clinical and the immune response to CsA in two Omenn patients and also examined the gene expression profile associated with good clinical response to such therapy. T cell receptor diversity was studied in cells obtained from OS patients during CsA therapy. Characterization of gene expression in these cells was carried out by using the TaqMan low-density array. One patient showed complete resolution of his symptoms after CsA therapy. The other patient showed selective response of his oligoclonal T cell population and combination therapy was required to control his symptoms. Transcriptional profile associated with good clinical response to CsA therapy revealed significant changes in 26·6% of the tested genes when compared with the transcriptional profile of the cells before treatment. Different clinical response to CsA in two OS patients is correlated with their immunological response. Varying clonal expansions in OS patients can cause autoimmune features and can respond differently to immunosuppressive therapy; therefore, additional treatment is sometimes indicated. CsA for OS patients causes regulation of genes that are involved closely with self-tolerance and autoimmunity.

Angiotensin II signalling and calcineurin in cardiac fibroblasts: differential effects of calcineurin inhibitors FK506 and cyclosporine A

INTRODUCTION

Cardiac remodelling is controlled by complex systems, including activation of the renin-angiotensin system (RAS) and signalling through MAP kinases and Ca2+-activated calcineurin. Whether Ang II, which increases [Ca2+]i and stimulates MAP kinases, mediates myocardial effects through calcineurin-dependent pathways remain unclear. We investigated effects of two calcineurin inhibitors, cyclosporine A (CsA) and tacrolimus (FK506) (10-10-10-6 mol/L, 20 mins) on activation of MAP kinases and on growth, pro-fibrotic and pro-inflammatory responses in Ang II-stimulated rat cardiac fibroblasts.

METHODS AND RESULTS

Ang II increased phosphorylation of ERK1/2 and p38MAPK (1.5-1.8-fold, p<0.05) without effect on JNK. FK506, but not CsA, attenuated Ang II-stimulated MAP kinase activation. Molecular indices of cell growth (proliferating cell nuclear antigen (PCNA)), fibrosis (fibronectin, pro-collagen) and inflammation (iNOS), were upregulated by Ang II (12 hrs). FK506 and CsA inhibited PCNA effects. Ang II-induced pro-fibrotic and pro-inflammatory responses were inhibited by CsA. Ang II receptors, AT1R and AT2R, were not influenced by calcineurin inhibitors. Our data indicate differential calcineurin inhibitor sensitivity of MAP kinases and cellular responses in Ang II-stimulated fibroblasts. p38MAP kinase and ERK1/2 are regulated in a FK506-sensitive manner, whereas fibrosis and inflammation are CsA-sensitive. Cell proliferation is inhibited by both FKC506 and CsA. These are post-receptor phenomena, since AT1R and AT2R status was unaltered by treatment.

CONCLUSIONS

Our findings identify an important role for calcineurin in MAP kinase/growth/pro-fibrotic/pro-inflammatory signalling by Ang II in cardiac fibroblasts. Although both FK506 and CsA inhibit calcineurin, they exert differential effects on molecular and cellular responses. Such differences may contribute to variable clinical responses of these agents.

Thrombosis and inflammatory bowel disease: a call for improved awareness and prevention

Thrombotic complications in patients with inflammatory bowel disease (IBD) are common and require improved awareness and prevention. In this review the interface between IBD and thrombosis is discussed, with emphasis on risk assessment and data to aid clinical decision making. Thromboembolic complications are 3-fold more likely in IBD patients than controls and the relative risk exceeds 15 during disease flares. Improved assessment of thrombosis risk for an individual patient includes thorough personal and family history and awareness of prothrombotic medications and lifestyle choices. Patients with the highest risk of thrombosis are those with active colonic disease, personal or strong family history of thrombosis, and those with significant acquired risk factors. Combined risk factors or hospitalization should prompt mechanical thromboprophylaxis. Indications for prophylactic anticoagulation are not defined currently by clinical studies, especially in pediatric patients, although some groups now advocate prophylactic anticoagulation for all hospitalized IBD patients and even some outpatients with disease flares. Thrombosis management requires a multidisciplinary therapeutic approach to balance anticoagulation and bleeding risk. While bleeding may occur with anticoagulation in IBD, data and experience indicate that therapeutic heparin is safe and bleeding manifestations can be managed supportively in most patients. Until prospective trials of prophylactic anticoagulation are published, management of thrombotic risk and prophylaxis in IBD will remain a clinical challenge.

Tacrolimus versus cyclosporine microemulsion for heart transplant recipients: a meta-analysis

BACKGROUND

Tacrolimus and cyclosporine microemulsion are the 2 major immunosuppressants for heart transplantation. Several studies have compared these 2 drugs, but the outcomes were not consistent. This meta-analysis of randomized controlled trials compared the beneficial and harmful effects of tacrolimus and microemulsion cyclosporine for heart transplant recipients.

METHODS

Electronic databases and manual bibliography searches were conducted. A meta-analysis was performed of all randomized controlled trials comparing tacrolimus with cyclosporine microemulsion as primary immunosuppression for heart transplant recipients. Data for mortality, acute rejection, withdrawals, and adverse events were extracted. The combined results of the data of the randomized controlled trials were summarized as relative risk with 95% confidence intervals.

RESULTS

The study assessed 7 randomized controlled trials including 885 patients. There was no difference in mortality at 1 year between recipients treated with tacrolimus and cyclosporine microemulsion. Tacrolimus-treated patients had less acute rejection risk at 6 months and 1 year. Fewer patients stopped tacrolimus than cyclosporine microemulsion. The rate of new-onset diabetes mellitus requiring insulin treatment was higher with tacrolimus. More post-transplantation hypertension occurred with cyclosporine microemulsion. The groups had comparable incidences of malignancy and renal failure needing dialysis.

CONCLUSIONS

The use of tacrolimus as primary immunosuppressant for heart transplant recipients results in comparable survival and a significant reduction in acute rejection compared with cyclosporine microemulsion.

Carotid and femoral atherosclerosis in chronic hepatitis C: a 5-year follow-up

The objective of this study was to assess the progression of atherosclerosis in carotid and femoral arteries after a 5-year period using ultrasound in subjects with chronic hepatitis C and in controls matched for classic atherosclerotic risk factors. A total of 40 patients and 40 controls were assessed by echocolor Doppler in 2001 and in 2006 to evaluate plaque and intima-media thickness. The patients showed no changes in plaque and intima-media thickness during the 5-year period in all districts examined, whereas a significant increase in intima-media thickness in the carotid sections was recorded in the controls. Chronic hepatitis C seems to cause delay in the atherosclerotic process.

Cardiac allograft vasculopathy and insulin resistance--hope for new therapeutic targets

Cardiac allograft vasculopathy (CAV) is a major cause of death in patients surviving more than 1 year after heart transplantation. An important cluster of CAV risk factors occurs as a consequence of insulin resistance and manifests as part of the metabolic syndrome. This article summarizes the pathologic features of CAV and reviews the contribution of the major components of insulin resistance in CAV development and progression. It focuses on the few studies that have analyzed the impact of the individual metabolic abnormalities and inflammation and on therapeutic strategies to minimize the clinical manifestation of insulin resistance after heart transplantation.

Cardiac allograft vasculopathy and insulin resistance--hope for new therapeutic targets

Cardiac allograft vasculopathy (CAV) is a major cause of death in patients surviving more than 1 year after heart transplantation. An important cluster of CAV risk factors occurs as a consequence of insulin resistance and manifests as part of the metabolic syndrome. This article summarizes the pathologic features of CAV and reviews the contribution of the major components of insulin resistance in CAV development and progression. It focuses on the few studies that have analyzed the impact of the individual metabolic abnormalities and inflammation and on therapeutic strategies to minimize the clinical manifestation of insulin resistance after heart transplantation.

Subclinical inflammation in renal transplant recipients: impact of cyclosporine microemulsion versus tacrolimus

BACKGROUND

Renal insufficiency and renal transplant (RT) provoke a microinflammatory state that leads to increased atherosclerosis. It is not fully known whether calcineurin inhibitors (CNIs) play a role in the inflammation observed in these patients or whether any differences exist between CNIs.

OBJECTIVES

The study aimed to establish differences in the inflammatory state of two groups treated with cyclosporine microemulsion (CyA) or tacrolimus (TC).

PATIENTS AND METHODS

This prospective study included 81 RT patients divided into two groups according to the CNI: CyA group, n = 35 versus TC group, n = 46. The markers of inflammation (MIF) were determined preRT and at 3 and 12 months' postRT: C-reactive protein (CRP), serum amyloid protein A (SAA), interleukin-6 (IL-6), soluble interleukin-2 receptor (sIL-2R), tumor necrosis factor-alpha (TNF-alpha), and pregnancy-associated plasma protein A (PAPP-A). Samples were collected in stable patients in the absence of rejection, active infection, or inflammatory processes.

RESULTS

No significant differences existed between the markers of inflammation in the two treatment groups prior to transplantation. At 3 months' posttransplant, patients treated with CyA showed significantly higher levels of IL-6 (P = .05), SAA (P = .03), and sIL-2R (P = .008) compared with patients treated with TC. These differences were maintained for IL-6 (P = .03) and sIL-2R (P = .027) at 12 months' posttransplant. A multivariate analysis at 3 months showed that only age [OR 10.1; CI (95% 2.6-38.4); P = .001], SAA [OR 4.8; IC (95% 1.4-16.5); P = .015], and sIL-2R [OR 4.9; IC (95% 1.5-16.2); P = .009] were independent predictors of the CNI used. At 12 months, age [OR 3.7; IC (95% 0.9-14.2] and sIL-2R [OR 6.04; IC (95% 1.5-23); P = .006] continued to be independent predictors.

CONCLUSIONS

Patients treated with CyA displayed significantly higher levels of inflammatory markers (IL-6, SAA, sIL-2R) at 3 and 12 months' posttransplantation, independent of age, gender, time on dialysis, diabetes mellitus (preRT and de novo postRT), and renal function measured by serum creatinine.