Potential usefulness of inflammatory markers to monitor respiratory functional impairment in sarcoidosis

Management of cardiac sarcoidosis

Cardiac sarcoidosis (CS) is a form of inflammatory cardiomyopathy associated with significant clinical complications such as high-degree atrioventricular block, ventricular tachycardia, and heart failure as well as sudden cardiac death. It is therefore important to provide an expert consensus statement summarizing the role of different available diagnostic tools and emphasizing the importance of a multidisciplinary approach. By integrating clinical information and the results of diagnostic tests, an accurate, validated, and timely diagnosis can be made, while alternative diagnoses can be reasonably excluded. This clinical expert consensus statement reviews the evidence on the management of different CS manifestations and provides advice to practicing clinicians in the field on the role of immunosuppression and the treatment of cardiac complications based on limited published data and the experience of international CS experts. The monitoring and risk stratification of patients with CS is also covered, while controversies and future research needs are explored.

Neurosarcoidosis and Neurologic Complications of Sarcoidosis Treatment

Sarcoidosis is an immune-mediated multisystem granulomatous disorder. Neurosarcoidosis (NS) accounts for 5% to 35% of cases. The diagnostic evaluation of NS can be a clinical challenge. Gadolinium-enhanced magnetic resonance imaging (MRI) is the gold standard to evaluate central nervous system NS. In almost all cases treatment is warranted. Although glucocorticoids remain the first-line therapy in patients with sarcoidosis, in NS timely initiation of second- or third-line treatment is strongly recommended. Of these, tumor necrosis factor-alpha inhibitors are the most promising. However, the treatment itself may be responsible for/associated with developing neurologic symptoms mimicking NS. Thus, it is important to consider the possibility of drug-induced neurologic symptoms in sarcoidosis.

Diagnosis of Pulmonary Sarcoidosis

Diagnosis of sarcoidosis depends on a compatible clinical and imaging presentation, histologic finding of non-necrotizing granulomatous inflammation, and exclusion of alternative causes of granulomatous diseases. This study has reviewed the diagnostic algorithms and approaches of sarcoidosis.

Biomarkers and molecular endotypes of sarcoidosis: lessons from omics and non-omics studies

Sarcoidosis is a chronic granulomatous disorder characterized by unknown etiology, undetermined mechanisms, and non-specific therapies except TNF blockade. To improve our understanding of the pathogenicity and to predict the outcomes of the disease, the identification of new biomarkers and molecular endotypes is sorely needed. In this study, we systematically evaluate the biomarkers identified through Omics and non-Omics approaches in sarcoidosis. Most of the currently documented biomarkers for sarcoidosis are mainly identified through conventional "one-for-all" non-Omics targeted studies. Although the application of machine learning algorithms to identify biomarkers and endotypes from unbiased comprehensive Omics studies is still in its infancy, a series of biomarkers, overwhelmingly for diagnosis to differentiate sarcoidosis from healthy controls have been reported. In view of the fact that current biomarker profiles in sarcoidosis are scarce, fragmented and mostly not validated, there is an urgent need to identify novel sarcoidosis biomarkers and molecular endotypes using more advanced Omics approaches to facilitate disease diagnosis and prognosis, resolve disease heterogeneity, and facilitate personalized medicine.

Risk Indicators of Sarcoidosis Evolution-Unified Protocol (RISE-UP): protocol for a multi-centre, longitudinal, observational study to identify clinical features that are predictive of sarcoidosis progression

INTRODUCTION

Sarcoidosis is a pulmonary and systemic granulomatous disease with a wide range of potential outcomes, from spontaneous resolution to end-stage organ damage and death. Currently, clinicians have no easy-to-use risk stratification tools for important clinical outcomes in sarcoidosis, such as progressive lung disease. This study will address two clinical practice needs: (1) development of a risk calculator that provides an estimate of the likelihood of pulmonary progression in sarcoidosis patients during the follow-up period and (2) determine the optimal interval for serial clinical monitoring (eg, 6, 12, 18 months) using these risk prediction tools.

METHODS AND ANALYSIS

The Risk Indicators of Sarcoidosis Evolution-Unified Protocol study is a National Institutes of Health-sponsored, longitudinal observational study of adults with pulmonary sarcoidosis who will be enrolled at five US tertiary care centres. Participants will be evaluated at approximately 6-month intervals for up to 60 months with collection of lung function, blood samples and clinical data. The target sample size is 557 and the primary objective is to determine which clinical features measured during a routine clinic visit carry the most prognostic information for predicting clinical progression of pulmonary sarcoidosis over the follow-up period. The primary outcome measure will be quantified by a clinically meaningful change in forced vital capacity, forced expiratory volume in 1 s or diffusing capacity of the lung for carbon monoxide. The secondary objective is to determine if blood biomarkers measured during a routine clinic visit can improve the risk assessment modelling for progression of pulmonary sarcoidosis over the follow-up period.

ETHICS AND DISSEMINATION

The study protocol has been approved by the Institutional Review Boards at each centre and the reliance Institutional Review Board overseeing the study (WCG, Protocol #20222400). Participants will provide informed consent prior to enrolment. Results will be disseminated via publication in a relevant peer-reviewed journal.

TRIAL REGISTRATION NUMBER

NCT05567133.

Serum amyloid A—A potential therapeutic target for hyper-inflammatory syndrome associated with COVID-19

Serum amyloid-A (SAA) is associated with inflammatory disorders such as rheumatoid arthritis, Familial Mediterranean Fever, sarcoidosis, and vasculitis. There is accumulating evidence that SAA is a reliable biomarker for these autoinflammatory and rheumatic diseases and may contribute to their pathophysiology. Hyperinflammatory syndrome associated with COVID-19 is a complex interaction between infection and autoimmunity and elevation of SAA is strongly correlated with severity of the inflammation. In this review we highlight the involvement of SAA in these different inflammatory conditions, consider its potential role and discuss whether it could be a potential target for treatment of the hyperinflammatory state of COVID-19 with many potential advantages and fewer adverse effects. Additional studies linking SAA to the pathophysiology of COVID-19 hyper-inflammation and autoimmunity are needed to establish the causal relationship and the therapeutic potential of inhibitors of SAA activity.

Diagnostic accuracy of interleukin-2 receptor in sarcoidosis: a systematic review and meta-analysis

INTRODUCTION

Soluble interleukin-2 receptor (sIL-2 R), a valuable diagnostic biomarker for sarcoidosis, has been reported with variable results. Based on the literatures currently accessible, a systematic review and meta-analysis of the diagnostic performance of serum sIL-2 R for sarcoidosis were performed.

METHODS

Relevant studies investigating sIL-2 R for sarcoidosis diagnosis in several databases were searched and data on sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), and diagnostic odds ratio (DOR) were pooled by STATA 16.0 software. Overall test performance was assessed using summary receiver operating characteristic curves and the area under the curve (AUC). Potential publication bias was assessed by Deeks test.

RESULTS

We included eleven studies involving 1,424 subjects, with 1,099 cases of sarcoidosis and 325 of non-sarcoidosis. The pooled parameters of sIL-2 R in diagnosing sarcoidosis were summarized as follows: sensitivity, 0.85 (95% CI: 0.72-0.93); specificity, 0.88 (95% CI: 0.72-0.96); PLR, 7.3 (95% CI: 2.7-20.1); NLR, 0.17 (95% CI:0.08-0.36); DOR, 44 (95% CI: 8-231); and the AUC, 0.93 (95% CI: 0.90-0.95). No publication bias was identified (P = 0.64).

CONCLUSIONS

Evidence suggests sIL-2 R performs well in diagnosing sarcoidosis. Nevertheless, results of sIL-2 R assay should be interpreted with other diagnostic examinations.

Serum soluble interleukin-2 receptor (sIL-2R) is an accurate biomarker for dengue-associated hemophagocytic lymphohistiocytosis syndrome diagnosed by Hscore

Objective

Hemophagocytic lymphohistiocytosis is a potentially fatal complication of severe dengue fever. Here we evaluated the serum soluble IL-2R levels as potential biomarker for identifying HLH in patients with dengue fever.

Methods

In this cross-sectional study conducted in a tertiary care center of a teaching hospital, subjects with dengue and fever of more than 5 days, leukopenia/thrombocytopenia and/or hepatosplenomegaly were studied. Data were collected to compare sIL-2R values and serum ferritin with Hscore and Histiocyte Society 2004 criteria. Relevant statistical methods were used.

Results

80 subjects with severe dengue fever were analyzed with relevant investigations. Mean H score was 219.2 ± 17.6 in 18 dengue patients with HLH v/s 166.2 ± 11.2 in 62 patients without HLH (p =  < 0.001). Serum ferritin (11,230.5 v/s 7853.5, p = 0.013) and sIL-2R (32,917.5 v/s 6210, p = < 0.001) were significantly higher in those patients with HLH. sIL-2R correlated very well with HScore (r = 0.98, p < 0.001) compared to ferritin (r = 0.51, p < 0.001) with an AUROC of 1.00 compared to 0.694 (95% CI 0.557–0.831) of serum ferritin for diagnosing HLH. A cut-off value of 10,345 pg/ml for sIL-2R had a sensitivity and specificity of 100% for HLH, whereas, a ferritin value of 8613 ng/ml had only 67% sensitivity and 55% specificity.

Conclusion

sIL-2R could be a single most useful biomarker to differentiate dengue fever patients who are likely to progress to HLH, from those that are not. Full workup for HLH could be limited only to those patients with elevated sIL-2R, especially in resource limited settings.

Supplementary Information

The online version contains supplementary material available at 10.1007/s15010-022-01906-8.

Serum amyloid A/anti-CCL20 induced the rebalance of Th17/regulatory T cells in SodA-induced sarcoidosis

Sarcoidosis is a multisystemic granulomatous inflammation associated with Th17/regulatory T cell (Treg) polarization. As a marker of inflammation, serum amyloid A (SAA) could upregulate the expression of chemokine ligand 20 (CCL20), which induces the migration of Treg cells and Th17 cells by binding and activating thechemokine C-C receptor (CCR) 6. Our goal was to determine whether SAA/anti-CCL20 induces Th17/Treg rebalance in pulmonary sarcoidosis. The deposition of SAA- and Th17/Treg-related proteins in SodA-induced granulomas was tested using immunohistochemistry. Mice with SodA-induced sarcoidosis were treated with SAA or SAA + anti-CCL20, and then Th1/Th2 and Th17/Treg cells were detected by fluorescence-activated cell sorting (FACS) analysis. The expression of SAA/CCL20 and IL-23/IL-17A was detected by enzyme-linked immunosorbent assay (ELISA) and multiplex. Key proteins in the TGF-β/Smad signaling pathway were tested by western blot. SAA mainly plays a pro-inflammatory role by promoting the expression of CCL20 and IL-17A in bronchoalveolar lavage fluid (BALF) and serum, exacerbating this elevation of CD4+/CD8+ T cells in both mediastinal lymph nodes (LNs) and BALF, as well as proliferating Th1 in LNs in SodA-induced pulmonary sarcoidosis. In addition, SAA could also promote the proliferation of Tregs in LNs. Intriguingly, blocking of CCL20 could partially reverse the expression of Th17-related cytokine, ameliorate Th1/Th2 and Treg/Th17 bias in mice with SodA-induced pulmonary sarcoidosis, and rescue the overactivation of the TGF-β/Smad2/Smad3 signaling pathway. Anti-CCL20 may have the potential for therapeutic translation, targeting on the immunopathogenesis of pulmonary sarcoidosis.

Defining CD4 T helper and T regulatory cell endotypes of progressive and remitting pulmonary sarcoidosis (BRITE): protocol for a US-based, multicentre, longitudinal observational bronchoscopy study

INTRODUCTION

Sarcoidosis is a multiorgan granulomatous disorder thought to be triggered and influenced by gene-environment interactions. Sarcoidosis affects 45-300/100 000 individuals in the USA and has an increasing mortality rate. The greatest gap in knowledge about sarcoidosis pathobiology is a lack of understanding about the underlying immunological mechanisms driving progressive pulmonary disease. The objective of this study is to define the lung-specific and blood-specific longitudinal changes in the adaptive immune response and their relationship to progressive and non-progressive pulmonary outcomes in patients with recently diagnosed sarcoidosis.

METHODS AND ANALYSIS

The BRonchoscopy at Initial sarcoidosis diagnosis Targeting longitudinal Endpoints study is a US-based, NIH-sponsored longitudinal blood and bronchoscopy study. Enrolment will occur over four centres with a target sample size of 80 eligible participants within 18 months of tissue diagnosis. Participants will undergo six study visits over 18 months. In addition to serial measurement of lung function, symptom surveys and chest X-rays, participants will undergo collection of blood and two bronchoscopies with bronchoalveolar lavage separated by 6 months. Freshly processed samples will be stained and flow-sorted for isolation of CD4 +T helper (Th1, Th17.0 and Th17.1) and T regulatory cell immune populations, followed by next-generation RNA sequencing. We will construct bioinformatic tools using this gene expression to define sarcoidosis endotypes that associate with progressive and non-progressive pulmonary disease outcomes and validate the tools using an independent cohort.

ETHICS AND DISSEMINATION

The study protocol has been approved by the Institutional Review Boards at National Jewish Hospital (IRB# HS-3118), University of Iowa (IRB# 201801750), Johns Hopkins University (IRB# 00149513) and University of California, San Francisco (IRB# 17-23432). All participants will be required to provide written informed consent. Findings will be disseminated via journal publications, scientific conferences, patient advocacy group online content and social media platforms.

Association of high serum soluble interleukin 2 receptor levels with risk of adverse events in cardiac sarcoidosis

Aims

Although soluble interleukin 2 receptor (sIL‐2R) is a potentially useful biomarker in the diagnosis and evaluation of disease severity in patients with sarcoidosis, its prognostic implication in patients with cardiac sarcoidosis (CS) is unclear. We sought to investigate whether sIL‐2R was associated with clinical outcomes and to clarify the relationship between sIL‐2R levels and disease activity in patients with CS.

Methods and results

We examined 83 consecutive patients with CS in our hospital who had available serum sIL‐2R data between May 2003 and February 2020. The primary outcome was a composite of advanced atrioventricular block, ventricular tachycardia or ventricular fibrillation, heart failure hospitalization, and all‐cause death. Inflammatory activity in the myocardium and lymph nodes was assessed by ¹⁸F‐fluorideoxyglucose positron emission tomography/computed tomography. During a median follow‐up period of 2.96 (IQR 2.24–4.27) years, the primary outcome occurred in 24 patients (29%). Higher serum sIL‐2R levels (>538 U/mL, the median) were significantly related to increased incidence of primary outcome (P = 0.037). Multivariable Cox regression analysis showed that a higher sIL‐2R was independently associated with an increased subsequent risk of adverse events (HR 3.71, 95% CI 1.63–8.44, P = 0.002), even after adjustment for significant covariates. sIL‐2R levels were significantly correlated to inflammatory activity in lymph nodes (r = 0.346, P = 0.003) but not the myocardium (r = 0.131, P = 0.27).

Conclusions

Increased sIL‐2R is associated with worse long‐term clinical outcomes accompanied by increased systemic inflammatory activity in CS patients.

Epigenetics and sarcoidosis

Epigenetic modifications are emerging as important regulatory mechanisms of gene expression in lung disease, given that they are influenced by environmental exposures and genetic variants, and that they regulate immune and fibrotic processes. In this review, we introduce these concepts with a focus on the study of DNA methylation and histone modifications and discuss how they have been applied to lung disease, and how they can be applied to sarcoidosis. This information has implications for other exposure and immunologically mediated lung diseases, such as chronic beryllium disease, hypersensitivity pneumonitis, and asbestosis.

Elevated Serum Amyloid a Levels Are not Specific for Sarcoidosis but Associate with a Fibrotic Pulmonary Phenotype

Elevated Serum Amyloid A (SAA) levels have been found in several inflammatory diseases, including sarcoidosis. SAA is suggested to be involved in sarcoidosis pathogenesis by involvement in granuloma formation and maintenance. We hypothesized that SAA serum levels would be higher in sarcoidosis compared to other non-infectious granulomatous and non-granulomatous diseases. SAA levels were measured in serum from sarcoidosis, Hypersensitivity pneumonitis (HP), and (eosinophilic) granulomatosis with polyangiitis ((E)GPA) patients. Idiopathic pulmonary fibrosis (IPF) patients were included as non-granulomatous disease group. SAA levels of patients with sarcoidosis (31.0 µg/mL), HP (23.4 µg/mL), (E)GPA (36.9 µg/mL), and IPF (22.1 µg/mL) were all higher than SAA levels of healthy controls (10.1 µg/mL). SAA levels did not differ between the diagnostic groups. When SAA serum levels were analyzed in sarcoidosis subgroups, fibrotic sarcoidosis patients showed higher SAA levels than sarcoidosis patients without fibrosis (47.8 µg/mL vs. 29.4 µg/mL, p = 0.005). To conclude, the observation that fibrotic sarcoidosis patients have higher SAA levels, together with our finding that SAA levels were also increased in IPF patients, suggests that SAA may next to granulomatous processes also reflect the process of fibrogenesis. Further studies should clarify the exact role of SAA in fibrosis and the underlying mechanisms involved.

Serum Amyloid A in Inflammatory Rheumatic Diseases: A Compendious Review of a Renowned Biomarker

Serum amyloid A (SAA) is an acute phase protein with a significant importance for patients with inflammatory rheumatic diseases (IRD). The central role of SAA in pathogenesis of IRD has been confirmed by recent discoveries, including its involvement in the activation of the inflammasome cascade and recruitment of interleukin 17 producing T helper cells. Clinical utility of SAA in IRD was originally evaluated nearly half a century ago. From the first findings, it was clear that SAA could be used for evaluating disease severity and monitoring disease activity in patients with rheumatoid arthritis and secondary amyloidosis. However, cost-effective and more easily applicable markers, such as C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR), overwhelmed its use in clinical practice. In the light of emerging evidences, SAA has been discerned as a more sensitive biomarker in a wide spectrum of IRD, especially in case of subclinical inflammation. Furthermore, a growing number of studies are confirming the advantages of SAA over many other biomarkers in predicting and monitoring response to biological immunotherapy in IRD patients. Arising scientific discoveries regarding the role of SAA, as well as delineating SAA and its isoforms as the most sensitive biomarkers in various IRD by recently developing proteomic techniques are encouraging the revival of its clinical use. Finally, the most recent findings have shown that SAA is a biomarker of severe Coronavirus disease 2019 (COVID-19). The aim of this review is to discuss the SAA-involving immune system network with emphasis on mechanisms relevant for IRD, as well as usefulness of SAA as a biomarker in various IRD. Therefore, over a hundred original papers were collected through an extensive PubMed and Scopus databases search. These recently arising insights will hopefully lead to a better management of IRD patients and might even inspire the development of new therapeutic strategies with SAA as a target.

Serum B cell activating factor (BAFF) and sarcoidosis activity

Objectives

This study aims to determine the relationship between the severity of sarcoidosis and serum B-cell activating factor (BAFF) concentrations.

Patients and methods

This cross-sectional study was conducted between December 2015 and March 2018 on 55 patients with sarcoidosis (16 males, 39 females; mean age, 39.9; range 25 to 60 years) and 28 healthy subjects (7 males, 20 females; mean age, 39; range 25 to 60 years). The sarcoidosis patients were divided into active chronic sarcoidosis and acute sarcoidosis groups. The diagnosis of sarcoidosis was based on clinical, radiological, and pathologic findings. Also, the diagnosis of the active disease was based on the level of angiotensin-converting enzyme, active skin, eye, and lung lesions. Scadding score was also measured, and other patient information was collected by pre-designed questionnaires.

Results

The most involved organs were the skin (92.7%) and joints (92.3%), respectively. The mean BAFF concentration in both active chronic sarcoidosis (p=0.001) and acute sarcoidosis (p=0.001) groups was significantly higher than the control group, but the mean level of BAFF in these two groups was not significantly different (p=0.351). Between two groups of patients, only calcium (p=0.001) and forced vital capacity (p=0.021) were higher in the acute group of sarcoidosis. Also, among the factors associated with active chronic sarcoidosis and acute sarcoidosis, none was significantly correlated with BAFF.

Conclusion

Serum BAFF concentration was higher in patients with sarcoidosis, while this was not significantly different from increasing severity of symptoms. There was no significant difference in BAFF levels between acute sarcoidosis and active chronic types.

Catch the rainbow: Prognostic factor of sarcoidosis

Sarcoidosis is a systemic, chronic, inflammatory disease characterized by noncaseating granuloma formations. The fact that the etiopathogenesis of the disease has not been elucidated yet brings it many theories and assumptions. Being a systemic disease and ability to involve many organs and systems, it attracts the attention of physicians from different branches. In addition to lung involvement, skin, eye, heart, and locomotor system involvement is an important clinical finding. Sarcoidosis may present with very different clinical presentations, and therefore, it is one of the important "imitators" in the medical literature. I like sarcoidosis as a "rainbow," it is a disease that contains the characteristics of many diseases. Different clinical, radiological, and laboratory prognostic factors (lupus pernio, chronic uveitis, late-onset disease, chronic hypercalcemia, nephrocalcinosis, Afro-American race, progressive pulmonary sarcoidosis, radiologic Stage 4, bone involvement, neurosarcoidosis, cardiac involvement, and chronic respiratory failure) have been defined in this "rainbow." Early identification of these factors plays an important role in the determination of treatment strategies, morbidity, and mortality of the disease. In this article, clinical, genetic, laboratory, and radiological factors that determine the prognosis of sarcoidosis are discussed in light of the latest data in the literature.

Serial investigation of Angiotensin-Converting Enzyme in sarcoidosis patients treated with Angiotensin-Converting Enzyme Inhibitor

BACKGROUND

Angiotensin-converting enzyme (ACE) is an acid glycoprotein that converts angiotensin I into angiotensin II. It is produced mainly by activated alveolar macrophages and it resulted elevated in sarcoidosis patients. ACE is the only biomarker mentioned in WASOG international guidelines for the diagnosis and follow-up of sarcoidosis patients but its sensitivity and specificity are low. This study aimed to analyze serial measurements of ACE levels in sarcoidosis patients stratified according to concomitant ACE-inhibitor therapies (ACEIs).

SUBJECTS AND METHODS

136 serum samples from sarcoidosis patients were retrospectively enrolled in the study. Serial ACE concentrations were measured once year for each patient. Population were divided according to radiogical stages and ACEIs.

RESULTS

ACE concentrations resulted higher in non-ACEIs than ACEIs group (p<E-04). This result was confirmed also stratifying population according to radiological stages particularly in stage 3 (p=2E-03) or stage 2 of the disease (p<1E-04). Considering ACEIs, serum ACE levels proved to be higher in sarcoidosis patients treated with zofenopril than in those treated with perindopril (p=2E-02), enalapril (p=2E-03) or ramipril (p=2E-04). Patients treated with ACEIs showed a progressive reduction in ACE levels to five years of follow-up (p=1.3E-02) and the zofenopril group recorded the highest ACE levels (p<1E-04).

CONCLUSIONS

This retrospective study investigated changes in ACE levels in patients with sarcoidosis treated or not treated with ACEIs. Considering the overall low sensitivity and specificity of this biomarker, we suggest systematically investigating medical drugs prescribed for patients with sarcoidosis, in order to optimize the interpretation of ACE in clinical management.

In Which Patients with Sarcoidosis Is FDG PET/CT Indicated?

Sarcoidosis is a granulomatous disease of which the etiology remains unknown. The diverse clinical manifestations may challenge clinicians, particularly when conventional markers are inconclusive. From various studies, it has become clear that fluorodeoxyglucose (FDG) positron emission tomography (PET)/CT aids in sarcoidosis care. In this article, an update on FDG PET/CT in sarcoidosis is provided. The use of FDG PET/CT in the diagnostic process of sarcoidosis is explained, especially in determining treatable inflammatory lesions in symptomatic patients with indecisive conventional tests. Furthermore, FDG PET/CT for evaluating the potential benefit of additional inflammatory treatment is described and its use in cardiac sarcoidosis is highlighted.

Paraoxonase 1 and atherosclerosis-related diseases

A direct and an indirect relationship between paraoxonase 1 (PON1) and atherosclerosis exists. Given PON1's physical location within high-density lipoprotein (HDL) particles and its recognized enzyme activity, it is certainly reasonable to suggest that PON1 facilitates the antiatherogenic nature of HDL particles. PON1 also plays a role in regulating reverse cholesterol transport, antioxidative, anti-inflammatory, antiapoptotic, vasodilative, and antithrombotic activities and several endothelial cell functions. HDL dysfunctionality is a more recent issue and seems to be centered on pathological conditions affecting HDL structure and size profiles. This review is focused on the role of PON1 status in different atherosclerosis-related diseases that we have studied over the last twenty years (coronary heart disease, acute ischemic stroke, diabetes mellitus type 2, end-stage renal disease, chronic obstructive pulmonary disease, and sarcoidosis) with the aim to determine the true value of PON1 as a biomarker. The role of PON1 in cancer is also covered, as risk factors and mechanisms underlying both atherosclerosis and cancer share common features.

Circulating lung biomarkers in idiopathic lung fibrosis and interstitial lung diseases associated with connective tissue diseases: Where do we stand?

Interstitial lung diseases (ILDs) are complex diseases with various courses where personalized medicine is highly expected. Biomarkers are indicators of physiological, pathological processes or of pharmacological response to therapeutic interventions. They can be used for diagnosis, risk-stratification, prediction and monitoring of treatment response. To better delineate the input and pitfalls of biomarkers in ILDs, we performed a systematic review and meta-analysis of literature in MEDLINE and Embase databases from January 1960 to February 2019. We focused on circulating biomarkers as having the highest generalizability. Overall, 70 studies were included in the review and 20 studies could be included in the meta-analysis. This review highlights that ILD associated with connective tissue diseases (CTD-ILD) and idiopathic pulmonary fibrosis (IPF) share common biomarkers, suggesting common pathophysiological pathways. KL-6 and SP-D, could diagnose lung fibrosis in both IPF and CTD-ILD, with KL-6 having the strongest value (OR: 520.95[110.07-2465.58], p<0.001 in IPF and OR:26.43[7.15-97.68], p<0.001 in CTD-ILD), followed by SPD (OR: 33.81[3.20-357.52], p = 0.003 in IPF and 13.24 [3.84-45.71] in SSc-ILD), MMP7 appeared as interesting for IPF diagnosis (p<0.001), whereas in SSc, CCL18 was associated with ILD diagnosis. Both CCL18 and KL-6 were predictive for the outcomes of ILDs, with higher predictive values for CCL18 in both IPF (OR:10.22[4.72-22.16], p<0.001 and in SSc [2.62[1.71-4.03], p<0.001). However, disease specific biomarkers are lacking and large longitudinal studies are needed before the translational use of the potential biomarkers in clinical practice. With the recent availability of new effective therapies in ILDs, further studies should assess response to treatment.

The NLRP3 inflammasome pathway is activated in sarcoidosis and involved in granuloma formation

Sarcoidosis is a disease characterised by granuloma formation. There is an unmet need for new treatment strategies beyond corticosteroids. The NLRP3 inflammasome pathway is expressed in innate immune cells and senses danger signals to elicit inflammatory interleukin (IL)-1β; it has recently become a druggable target. This prompted us to test the role of the NLRP3 inflammasome and IL-1β pathway in granuloma formation and sarcoidosis.

19 sarcoid patients and 19 healthy volunteers were recruited into this pilot study. NLRP3 inflammasome activity was measured in bronchoalveolar lavage (BAL) cells and lung and skin biopsies using immunohistochemistry, Western blot, reverse-transcriptase PCR and ELISA. For in vivo experiments we used the trehalose 6,6′-dimycolate-granuloma mouse model and evaluated lung granuloma burden in miR-223 knockout and NLRP3 knockout mice, as well as the treatment effects of MCC950 and anti-IL-1β antibody therapy.

We found strong upregulation of the NLRP3 inflammasome pathway, evidenced by expression of activated NLRP3 inflammasome components, including cleaved caspase-1 and IL-1β in lung granuloma, and increased IL-1β release of BAL cells from sarcoid patients compared to healthy volunteers (p=0.006). mRNA levels of miR-223, a micro-RNA downregulating NLRP3, were decreased and NLRP3 mRNA correspondingly increased in alveolar macrophages from sarcoid patients (p<0.005). NLRP3 knockout mice showed decreased and miR-223 knockout mice increased granuloma formation compared to wild-type mice. Pharmacological interference using NLRP3 pathway inhibitor MCC950 or an anti-IL-1β antibody resulted in reduced granuloma formation (p<0.02).

In conclusion, our data provide evidence of upregulated inflammasome and IL-1β pathway activation in sarcoidosis and suggest both as valid therapeutic targets.

Knowing when to use steroids, immunosuppressants or biologics for the treatment of sarcoidosis

Introduction: Care of patients with sarcoidosis requires familiarity with its natural history as well as of various immunosuppressants employed in its treatment. We would like to share our approach to management based on our experience and understanding of the relevant literature.Areas covered: Asymptomatic patients with pulmonary sarcoidosis ought to be managed conservatively. Systemic sarcoidosis with burdensome symptoms usually responds to corticosteroids, but one needs to consider the risk of long-term steroid toxicity as well as relapse. Rapidly tapering steroids can decrease cumulative exposure without compromising efficacy. Steroid-sparing anti-sarcoidosis (SSAS) agents take longer to act and are associated with unique but mostly reversible toxicities. Used judiciously and with careful monitoring, they effectively suppress granulomatous inflammation. Patients intolerant of or failing to improve with a particular drug can be switched to another, and occasionally combination therapy with two SSAS agents might prove effective. A small proportion of patients are refractory, but often achieve control and sometimes remission with stepping up to biologic therapy.Expert opinion: Adopting a strategy of early SSAS therapy ought to effectively control sarcoidosis and avoid harm from prolonged corticosteroid dosing.

Combined application of angiotensin converting enzyme and chitotriosidase analysis improves the laboratory diagnosis of sarcoidosis

Establishing the diagnosis of sarcoidosis most often requires biopsy and histopathologic evaluation, since there is no single marker with sufficient specificity and sensitivity for the disease. Our aims were to determine and compare the diagnostic accuracies of several potential biomarkers and to develop a combined biomarker analysis tool for the diagnosis of sarcoidosis. 133 healthy individuals and 104 patients with suspected sarcoidosis and diagnostic thoracic surgery were enrolled into this study. Histopathologic results were contrasted to biomarker levels of chitotriosidase (CTO), serum amyloid-A (SAA), soluble interleukin-2 receptor (sIL-2R), lysozyme (LZM) or angiotensin converting enzyme (ACE). Sarcoidosis was confirmed by histopathology in 69 patients. CTO activity, sIL-2R concentration and ACE activity could discriminate between sarcoidosis and control patients, while SAA and LZM concentrations could not. A new combined parameter, which was derived from the multiplication of ACE by CTO activities (double product) showed the best diagnostic accuracy in this clinical study: (AUC = 0.898, sensitivity: 90.5%, specificity: 79.3%, positive and negative predictive values: 90.5% and 79.3%, respectively). Sarcoidosis can be diagnosed with the combined analysis of ACE and CTO activities more accurately than with single serum biomarkers in the absence of invasive biopsy in the majority of cases with pulmonary manifestation of sarcoidosis.

Sensitivity and specificity of serum soluble interleukin-2 receptor for diagnosing sarcoidosis in a population of patients suspected of sarcoidosis

Background

The soluble interleukin 2 receptor (sIL-2R) has been proposed as a marker of disease activity in patients with sarcoidosis. However, no studies have evaluated whether serum sIL-2R measurement is of use in establishing the diagnosis of sarcoidosis in patients who are suspected of sarcoidosis among other diseases.

Methods

A cohort study was conducted, consisting of new patients who visited the immunology outpatient clinic and whose serum sIL-2R levels were available before a definitive diagnosis was established between February 2011 and February 2016. All patients underwent standard diagnostic testing for sarcoidosis (e.g. laboratory tests, radiographic and/or nuclear imaging and/or affected site biopsy). This resulted either in the diagnosis of sarcoidosis or the exclusion of sarcoidosis with the diagnosis of another disease. Results of sIL-2R and angiotensin-converting enzyme (ACE) levels, radiographic and nuclear imaging and histology results were collected and definitive diagnoses were recorded. Sensitivity, specificity, the concordance statistic from the receiver operating characteristic curve and Youden’s Index were calculated to assess the performance of sIL-2R in the diagnosis of sarcoidosis and were compared to ACE, currently one of the most used diagnostic biomarkers in the diagnosis of sarcoidosis.

Results

In total 983 patients were screened for inclusion, of which 189 patients met the inclusion criteria. A total of 101 patients were diagnosed with sarcoidosis after diagnostic workup, of whom 79 were biopsy-proven. In 88 patients a diagnosis other than sarcoidosis was made. The sensitivity and specificity of serum soluble interleukin 2 receptor levels to detect sarcoidosis were 88% and 85%. The sensitivity and specificity of ACE were 62% and 76%. Receiver operating characteristic curve analysis revealed that sIL-2R receptor is superior to ACE (p<0.0001).

Conclusion

Serum sIL-2R is a sensitive biomarker and superior to ACE in establishing the diagnosis of sarcoidosis and can be used to rule out sarcoidosis in patients suspected of sarcoidosis.

Serum Albumin as a Biomarker of Pulmonary Sarcoidosis Chronicity

OBJECTIVES

The duration of sarcoidosis is associated with a higher risk of irreversible pulmonary fibrosis. Sarcoidosis shows diverse clinical presentations, which may lead to a delayed diagnosis due to lack of a specific diagnostic test. Biomarkers of sarcoidosis duration have not been previously explored.

MATERIALS AND METHODS

A retrospective study was conducted to investigate independent biomarkers of pulmonary sarcoidosis duration.

RESULTS

A total of 108 cases with pulmonary sarcoidosis (mean age 53.4 years; 76.9% females; average duration of sarcoidosis 12 years) were included in the study. We found significant correlation between the duration of sarcoidosis and serum albumin levels (r=-0.414, p=0.0001), sedimentation rate (r=0.375, p=0.001), pulmonary artery systolic pressure (r= 0.468, p=0.003), diffusion capacity (r=-0.334, p=0.002), and age (r=0.492, p=0.0001). A multivariate linear regression analysis revealed that serum albumin levels (β=-5.242, 95% confidence interval [CI] -8.372 to -2.112, p=0.001) and age (β=0.367, 95% CI 0.164 to 0.570, p=0.001) were independent correlates of sarcoidosis duration. A receiver operating characteristics curve analysis for prediction of sarcoidosis of a >10 years duration gave an area under curve (AUC) of 0.722 (95% CI 0.620-0.824, p<0.0001) for serum albumin and an AUC of 0.665 (95% CI 0.561-0.768, p<0.004) for age. An albumin level <2.4 gm/dL yielded a 90.5% sensitivity and 98.2% specificity for predicting sarcoidosis of >10 years duration. In comparison, the patient age of 51.5 years yielded a 70.2% sensitivity and 50% specificity for predicting patients with sarcoidosis for >10 years.

CONCLUSION

The serum albumin level may be a biomarker of pulmonary sarcoidosis duration and chronicity of disease. Further investigations are required to confirm its predictive ability.

Prognostic Biomarkers of Sarcoidosis: A Comparative Study of Serum Chitotriosidase, ACE, Lysozyme, and KL-6

Purpose

Sarcoidosis is a systemic granulomatous disease with unknown etiology. Many clinical presentations have been reported, and acute disease needs to be distinguished from subacute and chronic disease. The unpredictable clinical course of the disease prompted us to evaluate the clinical utility of biomarker serum detection in sarcoidosis follow-up.

Methods

Serum concentrations of chitotriosidase, ACE, KL-6, and lysozyme were analyzed by different methods in a population of 74 sarcoidosis patients (46 on steroid therapy at sampling) regularly monitored at Siena Sarcoidosis Regional Referral Centre and in a group of controls with the aim of comparing their contribution to clinical management of sarcoidosis patients.

Results

KL-6 concentrations were significantly elevated in sarcoidosis patients with lung fibrosis and were significantly correlated with DLco and CPI score, while chitotriosidase was significantly higher in patients with extrapulmonary localizations. With a cut-off value of 303.5 IU/ml, KL-6 showed the best sensitivity (78%), while chitotriosidase reported the best specificity (85%) among the biomarkers.

Conclusions

KL-6 is a reliable biomarker of fibrotic lung involvement in sarcoidosis patients. Among biomarkers, KL-6 showed the best sensitivity and serum chitotriosidase the best specificity, even in patients on chronic steroid therapy, and seemed to correlate with extrapulmonary localizations.

First patient-centred set of outcomes for pulmonary sarcoidosis: a multicentre initiative

Introduction

Routine and international comparison of clinical outcomes enabling identification of best practices for patients with pulmonary sarcoidosis is lacking. The aim of this study was to develop a standard set of outcome measures for pulmonary sarcoidosis, using the value-based healthcare principles.

Methods

Six expert clinics for interstitial lung diseases in four countries participated in a consensus-driven RAND-modified Delphi study. A mixed-method approach was applied for the identification of an outcome measures set and initial conditions for patients with pulmonary sarcoidosis. The expert team consisted of multidisciplinary professionals (n=14) from Cleveland Clinic, Cincinnati MC, Erasmus MC, Leuven UZ, Royal Brompton and St. Antonius Hospital. During a ranking process, participants were instructed to rank variables on a scale from 1 to 10 based on whether it has (1) impact of the outcome on quality of life, (2) impact of quality of care on the outcome and (3) the number of patients negatively affected by the outcome.

Results

An outcome measures set was defined consisting of seven outcome measures: mortality, pulmonary function, soluble interleukin-2 receptor change as an activity biomarker, weight gain, quality of life, osteoporosis and clinical outcome status.

Discussion

Collecting outcomes in pulmonary sarcoidosis internationally and the use of a broadly accepted set can enable international comparison. Differences in outcomes can potentially be used as a starting point for quality improvement initiatives.

YKL-40, Soluble IL-2 Receptor, Angiotensin Converting Enzyme and C-Reactive Protein: Comparison of Markers of Sarcoidosis Activity

The aims of this study were to describe the clinical, radiological and immunological features of a population of sarcoidosis patients and to analyse chitinase-3-like protein 1 (YKL-40), soluble interleukin-2 receptor (sIL-2R), neopterin concentrations and adenosine deaminase (ADA) activity in serum of these patients in order to understand their potential as disease markers. Fifty-nine patients affected by chronic sarcoidosis, in active (20 patients) and inactive (39 patients) phase according to the clinical, radiological and laboratory criteria were studied. Serum YKL-40, sIL-2R, high-sensitive C-reactive protein (hs-CRP), neopterin levels and ADA activities were evaluated and compared with those of 25 healthy controls. Individuals with chronic sarcoidosis were significantly higher serum YKL-40, sIL-2R, neopterin, hs-CRP concentrations, angiotensin converting enzyme (ACE) and ADA activity than those of control subjects. Sarcoidosis patients in the active phase of the disease were significantly higher YKL-40, sIL-2R, hs-CRP levels and ACE activity than those in the inactive phase, while ADA activities and neopterin levels did not display any significant difference between the active and inactive disease groups. In comparison to the other parameters, as panel measurement of the serum YKL-40, sIL-2R, ACE and hs-CRP indicate a greater discrimination between active and inactive disease. The results indicate that serum YKL-40, sIL-2R, ACE and hs-CRP concentrations may be useful marker for monitoring sarcoidosis disease activity.

Significant elevation of the levels of B-cell activating factor (BAFF) in patients with sarcoidosis

B-cell activating factor (BAFF) plays an important role in the survival and differentiation of B-cells and production of antibodies. Recent studies show that the serum BAFF levels are elevated in patients with sarcoidosis; however, they have not studied the relationship of the finding with the clinical features of the disease. The purpose of the present study is to analyze the BAFF and to elucidate the relationship between BAFF levels and the disease activity or severity of sarcoidosis. Eighty-eight patients with sarcoidosis and 21 healthy volunteers were enrolled in the present study. The BAFF levels were measured by an enzyme-linked immunosorbent assay. To assess the disease severity, we examined the number of affected organs, Schadding stages, respiratory function impairment (RFI), and the scoring system developed by Wasfi et al. The serum BAFF levels in sarcoidosis patients were significantly higher than those in healthy volunteers (median 1553.0 vs 984.6 pg/ml, p < 0.001). There were positive correlations between the serum BAFF level and disease activity markers. In addition, there were positive correlations between the BAFF levels and the disease severity score in both the serum (R = 0.367, p < 0.001) and bronchoalveolar lavage fluid (BALF) (R = 0.376, p < 0.001). This study demonstrated that the BAFF levels in both the serum and BALF were positively correlated with the disease activity markers and disease severity. BAFF may be useful as an indicator of both the disease activity and severity.

Associations of lipoprotein subclasses and oxidative stress status in pulmonary and pulmonary plus extrapulmonary sarcoidosis

Background: Sarcoidosis is an inflammatory disease with pulmonary and extrapulmonary manifestations. In such pathologic conditions, increased oxidative stress and rearrangement of high-density lipoprotein (HDL) and low-density lipoprotein (LDL) may occur. Objective: This study evaluated association of oxidative stress and lipoprotein subclasses in severe forms of pulmonary and pulmonary plus extrapulmonary sarcoidosis. Methods: Lipid parameters, LDL and HDL subclass distributions, high-sensitivity C-reactive protein (hsCRP), serum amyloid A (SAA), paraoxonase 1 (PON1), malondialdehyde (MDA), total-oxidant status (TOS), sulfhydryl (SH) groups, pro-oxidant anti-oxidant balance (PAB) were determined in 77 patients (53 isolated pulmonary and 24 pulmonary plus extrapulmonary) and 139 controls. Results: Both pulmonary and extrapulmonary sarcoidosis patients had significantly higher levels of triglycerides and TOS (P<0.05) and more LDL II, LDL III, LDL IVA particles (P<0.01), but lower HDL size, SH groups (P<0.001), PON1 activity and less LDL I subclasses (P<0.05) than controls. In isolated pulmonary disease, HDL-cholesterol (P<0.01) was significantly lower whereas proportions of HDL 3a and PAB were significantly higher (P<0.05) when compared with the control group. PON1 was significantly higher in pulmonary than in combined pulmonary-extrapulmonary disease (P<0.05). In pulmonary sarcoidosis, TOS and PON1 correlated significantly with small-sized HDL particles (P<0.05). Conclusions: Both patient groups were characterized by adverse lipoprotein profile and elevated oxidative stress. In isolated pulmonary group significant associations of oxidative stress and HDL particles distribution was demonstrated. Pulmonary sarcoidosis was associated with higher PON1 activity and rearrangement of LDL particles did not depend on disease localization. (Sarcoidosis Vasc Diffuse Lung Dis 2018; 35: 198-205).

Soluble interleukin-2 receptor is a sensitive diagnostic test in adult HLH

Serum soluble interleukin-2 receptor (sIL-2r) is an important disease marker in hemophagocytic lymphohistiocytosis (HLH), but there are no published data on its diagnostic value in adults. We conducted a single-center retrospective study of 78 consecutive adults who had sIL-2r measured for suspected HLH. Serum sIL-2r levels were measured by enzyme-linked immunosorbent assay (adult reference range, 241-846 U/mL). There were 38 patients with HLH and 40 with a non-HLH diagnosis (such as sepsis, liver disease, histiocyte disorders, autoimmune disease, leukemia, or lymphoma). The receiver operating characteristic curve demonstrated that sIL-2r is a good to excellent diagnostic test for adult HLH, with an area under the curve (AUC) of 0.90 (95% confidence interval, 0.83-0.97) compared with AUC 0.78 (95% confidence interval, 0.67-0.88) for ferritin. The optimal threshold for sIL-2r was 2515 U/mL (sensitivity, 100%; specificity, 72.5%). Although there was a large indeterminate range for sIL-2r, a level of 2400 U/mL or less was helpful for ruling out HLH (sensitivity, 100%), and more than 10 000 U/mL was helpful for ruling in HLH (specificity, 93%). Higher mean sIL-2r levels were seen in malignancy-associated HLH (20 241 U/mL) compared with infection-associated HLH and macrophage activation syndrome (9720 and 5008 U/mL, respectively; P < .05). Levels above 10 000 U/mL were not associated with worse prognosis in patients with HLH. Serum sIL-2r is a sensitive test for diagnosis of adult HLH, but is not as specific as previously reported in children. Additional studies enriched with patients without HLH who have conditions associated with T-cell activation, such as lymphoma and autoimmune lymphoproliferative syndrome, are needed.

Candidate Serum Markers in Early Crohn's Disease: Predictors of Disease Course

BACKGROUND AND AIMS

More than half of patients with Crohn's disease [CD] develop disease complications requiring aggressive medical therapy or surgery over time. However, predicting disease course and treatment response remains difficult. We therefore identified distinctive serum analytes associated with disease activity and course in newly diagnosed, untreated patients at presentation and during their follow-up.

METHODS

In a pilot study, a multiplex immunoassay analysis on 36 markers was performed on serum from 20 CD patients at the time of primary diagnosis following endoscopic evaluation. The 12 most potent markers associated with disease activity, phenotype and course were analysed in a consecutive cohort of 66 CD patients at diagnosis and follow-up [n = 39]. A healthy control group [n = 20] was included as a reference.

RESULTS

CD patients had higher baseline levels of sTNF-R2 [p = 0.001], sIL-2R [p = 0.0001], and MMP-1 [p = 0.001] compared with healthy controls. Serial measurements revealed that these three analytes dropped statistically significantly from baseline level during remission and were high during exacerbation. Great decline of sTNF-R1 levels was found during remission, with 6.7-fold lower levels than in healthy controls [p = 0.015]. Patients who did not respond to initial prednisone treatment had higher baseline levels of sTNF-R2 [p = 0.001]. Patients experiencing relapses during follow-up had lower baseline sTNF-R2 and VCAM levels compared with patients with long-lasting remission.

CONCLUSIONS

In a large cohort of newly diagnosed untreated CD patients, we identified candidate serum markers [sTNF-R1, sTNF-R2, sIL-2R, and MMP-1] associated with disease activity. Furthermore, sTNF-R2 was associated with prednisone response and, together with VCAM, with long-lasting remission.

Biological role of the soluble interleukin-2 receptor in sarcoidosis

Sarcoidosis is a systemic inflammatory disease characterized by granulomatous inflammation. The soluble interleukin-2 receptor (sIL-2R) is used as a biomarker for disease severity in sarcoidosis. Moreover, rather than just a biomarker, evidence indicates that sIL-2R could be of biological significance in this disease. The aim of this review is to investigate both its qualities as a biomarker and a potential biological role in sarcoidosis. As a biomarker, the serum level of sIL-2R can be used to distinguish patients from healthy controls, active from inactive disease and to assess treatment success. Additionally, sIL-2R correlates with other biomarkers, including angiotensin-converting enzyme, and with lung function tests and nuclear imaging studies. In sarcoidosis T helper cells and alveolar macrophages are the most likely sources of sIL-2R. While most of the evidence indicates that sIL-2R is generated through proteolytic cleavage of membrane-bound IL-2Rα, no endogenous enzyme has been found to be clearly responsible for sIL-2R formation. It is unclear if sIL-2R has immunostimulatory, immunomodulatory or no functional effects, since conflicting results have been reported. Several potential mechanisms of sIL-2R's biological functions include IL-2 sequestration, prolonging IL-2 half-life, preventing activation of resting T cells or increasing affinity of IL-2Rβ for IL-2. The most likely function of sIL-2R is to modify IL-2 signaling. Increased levels of sIL-2R could either promote disease processes, represent an ineffective attempt to resolve the inflammation or have no effect at all. Further research is required to determine its exact role in the disease and thus its usefulness as a therapeutic target. (Sarcoidosis Vasc Diffuse Lung Dis 2017; 34: 122-129).

Risk assessment of patients with clinical manifestations of cardiac sarcoidosis with positron emission tomography and magnetic resonance imaging

BACKGROUND

Prior studies have shown that late gadolinium enhancement (LGE) on cardiac magnetic resonance (CMR) and fluorodeoxyglucose (FDG) positron emission tomography (PET) confer incremental risk assessment in patients with cardiac sarcoidosis (CS). However, the incremental prognostic value of the combined use of LGE and FDG compared to either test alone has not been investigated, and this is the aim of the present study.

METHODS

Retrospective observational study of 56 symptomatic patients with high clinical suspicion for CS who underwent LGE-CMR and FDG-PET and were followed for the occurrence of death and/or malignant ventricular arrhythmias (VA).

RESULTS

The combination of PET and CMR yielded the following groups: 1) LGE-negative/normal-PET (n=20), 2) LGE-positive/abnormal-FDG (n=20), and 3) LGE-positive/normal FDG (n=16). After a median follow-up of 2.6years (IQR 1.2-4.1), 16 patients had events (7 deaths, 10 VA). All, but 1, events occurred in patients with LGE. LGE-positive/abnormal-FDG (7 events, HR 10.1 [95% CI 1.2-84]; P=0.03) and LGE-positive/normal-FDG (8 events, HR 13.3 [1.7-107]; P=0.015) patients had comparable risk of events compared to the reference LGE-negative/normal-PET group. In adjusted Cox-regression analysis, presence of LGE (HR 18.1 [1.8-178]; P=0.013) was the only independent predictor of events.

CONCLUSION

CS patients with LGE alone or in association with FDG were at similar risk of future events, which suggests that outcomes may be driven by the presence of LGE (myocardial fibrosis) and not FDG (inflammation).

The effect of dietary components on inflammatory lung diseases - a literature review

Anti-inflammatory treatment in chronic inflammatory lung diseases usually involves glucocorticosteroids. With patients suffering from serious side effects or becoming resistant, specific nutrients, that are suggested to positively influence disease progression, can be considered as new treatment options. The dietary inflammatory index is used to calculate effects of dietary components on inflammation and lung function to identify most potent dietary components, based on 162 articles. The positive effects of n-3 PUFAs and vitamin E on lung function can at least partially be explained by their anti-inflammatory effect. Many other dietary components showed only small or no effects on inflammation and/or lung function, although the number of weighted studies was often too small for a reliable assessment. Optimal beneficial dietary elements might reduce the required amounts of anti-inflammatory treatments, thereby decreasing both side effects and development of resistance as to improve quality of life of patients suffering from chronic inflammatory lung diseases.

Enhanced LPS-induced activation of IL-27 signalling in sarcoidosis

RATIONALE

Granulomas in sarcoidosis have recently been described as containing Interleukin (IL)-27, one of the members of the IL-12 family of cytokines, which also includes IL-35. Levels of these cytokines and the IL-27 receptor subunits were hypothesised to differ between patients with sarcoidosis compared to healthy controls in peripheral blood.

METHODS

Using a cross-sectional study design, plasma and peripheral blood mononuclear cells (PBMC) were collected from patients and control subjects. Protein and mRNA (in PBMC) levels for IL-27 and IL-35 (IL27, EBI3, IL12A subunits) as well as IL-27 receptor (IL6ST and IL27RA subunits) were assessed spontaneously and following direct (LPS) and indirect (anti-CD3/28 activation beads) macrophage stimulation using RT- PCR, ELISA and flow cytometry.

RESULTS

Following stimulation with LPS, PBMC of patients with sarcoidosis displayed significantly enhanced expression of IL27 and EBI3 mRNA (p = 0.020 and p = 0.037 respectively) compared to PBMCs from healthy controls. There was also significantly enhanced production of IL-27 by PBMC from patients with sarcoidosis compared to healthy controls in response to LPS stimulation (p = 0.027). IL6ST mRNA and IL6ST protein were significantly lower in patients with sarcoidosis (mRNA p = 0.0002; MFI p = 0.0015) whilst IL27RA protein levels were significantly higher in patients with sarcoidosis compared to healthy controls (MFI p < 0.0001). Plasma IL-35 protein levels did not differ between control and sarcoidosis subjects (p = 0.23).

CONCLUSION

These results suggest there may be exaggerated activation of IL-27 signalling in response to LPS in sarcoidosis.

The Association between ESR and CRP and Systemic Hypertension in Sarcoidosis

Introduction. The association between the level of systemic inflammation and systemic hypertension (sHTN) among subjects with sarcoidosis has not been previously explored. Methods. A retrospective study was conducted to investigate the relation between the level of systemic inflammation in sarcoidosis, measured by various serum inflammatory markers, and sHTN. Results. Among a total of 108 cases with sarcoidosis (mean age: 53.4 years, 76.9% females), 55 (50.9%) had sHTN and 53 (49.1%) were normotensive. ESR was highly associated with sHTN. The patients with sHTN had higher mean ESR levels compared with normotensives (48.8 ± 35 versus 23.2 ± 27 mm/hr, resp.; P = 0.001). ROC curve analysis for ESR revealed an AUC value of 0.795 (95% CI: 0.692–0.897; P = 0.0001). With regard to CRP, there was a trend towards higher mean values in sHTN group (3.4 versus 1.7 mg/L; P = 0.067) and significantly higher prevalence of sHTN in the highest CRP quartile compared to the lowest one (69.6% versus 30%; OR 4.95; P = 0.017). ROC curve analysis for CRP revealed an AUC value of 0.644 (95% CI: 0.518–0.769; P = 0.03). On multivariate analysis, ESR and the CRP remained independent predictors for sHTN among subjects with sarcoidosis. Conclusion. Systemic inflammation is associated with the presence of sHTN in sarcoidosis.

Biomarkers in sarcoidosis

INTRODUCTION

Numerous biomarkers have been evaluated for the diagnosis, assessment of disease activity, prognosis, and response to treatment in sarcoidosis. In this report, we discuss the clinical and research utility of several biomarkers used to evaluate sarcoidosis. Areas covered: The sarcoidosis biomarkers discussed include serologic tests, imaging studies, identification of inflammatory cells and genetic analyses. Literature was obtained from medical databases including PubMed and Web of Science. Expert commentary: Most of the biomarkers examined in sarcoidosis are not adequately specific or sensitive to be used in isolation to make clinical decisions. However, several sarcoidosis biomarkers have an important role in the clinical management of sarcoidosis when they are coupled with clinical data including the results of other biomarkers.

Association of serum amyloid A and oxidative stress with paraoxonase 1 in sarcoidosis patients

BACKGROUND

It has been reported that high-density lipoprotein (HDL) particles have anti-inflammatory and antioxidant roles thanks to different enzymes such as paraoxonase 1 (PON1). Under inflammatory and oxidative stress conditions, HDL particles may lose their protective properties. Sarcoidosis is an inflammatory disease characterized by excessive oxidative stress. Serum amyloid A (SAA) is produced in liver and in granulomas, and its concentration increases in inflammatory conditions contributing to increased catabolism of HDL particles. The aim of our study was to determine PON1 activity, SAA concentration and their associations in patients with sarcoidosis.

MATERIALS AND METHODS

Inflammatory [high-sensitive C-reactive protein (hsCRP), angiotensin-converting enzyme (ACE), SAA], lipid [total cholesterol (TC), HDL-cholesterol (HDL-c), low-density lipoprotein cholesterol (LDL-c), triglycerides (TG)] oxidative stress status parameters [total oxidant status (TOS), malondialdehyde (MDA), pro-oxidant-antioxidant balance (PAB), sulfhydryl (SH) groups] and PON1 activities were determined in serum of 72 patients with sarcoidosis and 62 healthy subjects.

RESULTS

HsCRP (P < 0·05), TC, LDL-c, TG, SAA, TOS, MDA and PAB (P < 0·001) were significantly higher, whereas HDL-c, SH groups and PON1 activity (P < 0·001) were significantly lower in patients with sarcoidosis when compared with controls. PON1 showed significant association with SAA, MDA and PAB. It was shown that 71% of decrease in PON1 activity may be explained by increase in TOS, PAB and SAA concentration.

CONCLUSIONS

We found decreased PON1 activity and increased SAA concentration in patients with sarcoidosis. Inflammatory condition presented by high SAA was implicated in impaired HDL functionality evident through dysregulated PON1 activity. Excessive oxidative stress was also involved in dysregulation of PON1 activity.

Efficacy of adalimumab in sarcoidosis patients who developed intolerance to infliximab

BACKGROUND

Tumor necrosis factor-alpha (TNF-α) inhibitors are regarded as the third-line therapy in sarcoidosis, the first choice generally being infliximab. To date, data regarding response to adalimumab in sarcoidosis patients intolerant to infliximab are lacking. The objective of this retrospective observational study was to establish if adalimumab could achieve stabilization or improvement of the disease in refractory sarcoidosis patients who developed intolerance to infliximab.

MATERIAL AND METHODS

Sarcoidosis patients referred to St Antonius Interstitial Lung Diseases Center of Excellence, Nieuwegein, The Netherlands, between January 2008 and April 2015 who switched from infliximab to adalimumab were included. Changes in organ function, inflammatory biomarker levels, and adverse events were retrieved from medical records.

RESULTS

Out of 142 infliximab treated patients, 18 (13%) had to discontinue treatment due to antibody formation or severe adverse events and switched to adalimumab therapy. Organ function improved in 7 patients (39%), was stable in 6 patients (33%), and worsened in 5 patients (28%) after 12 months of treatment or after 6 months if evaluation after 12 months was not available (n = 4). In none of the patients biomarker levels of soluble interleukin-2 receptor (sIL-2R) deteriorated. Median decrease in sIL-2R was 3614 pg/mL. Most reported adverse event was infection (n = 10).

CONCLUSIONS

Adalimumab is an effective alternative for patients intolerant to infliximab. The switch to adalimumab achieved clinical improvement in 39% and stabilization in 33% of patients intolerant to infliximab. Further research is needed to develop guidelines on how to use adalimumab for sarcoidosis in terms of dosing regimen.

Refractory pulmonary sarcoidosis - proposal of a definition and recommendations for the diagnostic and therapeutic approach

Patients with sarcoidosis undergo spontaneous remission or may be effectively controlled with glucocorticoids alone in many cases. Progressive and refractory pulmonary sarcoidoisis constitute more than 10% of patients seen at specialized centers. Pulmonary fibrosis and associated complications, such as infections and pulmonary hypertension are leading causes of mortality. No universal definition of refractoriness exists, we therefore propose classifying patients as having refractory disease when the following criteria are fulfilled: (1) progressive disease despite at least 10 mg of prednisolone or equivalent for at least three months and need for additional disease-modifying anti-sarcoid drugs due to lack of efficacy, drug toxicity or intolerability and (2) treatment started for significant impairment of life due to progressive pulmonary symptoms. Both criteria should be fulfilled. Treatment options in addition to or instead of glucocorticoids for these patients include second- (methotrexate, azathioprine, leflunomide) and third-line agents (infliximab, adalimumab). Other immunmodulating agents can be used, but the evidence is very limited. Newer agents with anti-fibrotic properties, such as pirfenidone or nintedanib, might hold promise also for the pulmonary fibrosis seen in sarcoidosis. Treating physicians have to actively look for potentially treatable complications, such as pulmonary hypertension, cardiac disease or infections before patients should be classified as treatment-refractory. Ultimately, lung transplantation has to be considered as treatment option for patients not responding to medical therapy. In this review, we aim to propose a new definition of refractoriness, describe the associated clinical features and suggest the therapeutic approach.

Diagnosing sarcoidosis

PURPOSE OF REVIEW

The usual diagnostic criteria for sarcoidosis include the documentation of a compatible clinicoradiologic scenario, biopsy proof of granulomas, and exclusion of alternate causes for the findings. Establishing the presence of multisystem disease, and longitudinal assessment for the emergence of potential sarcoidosis mimics both strengthen the diagnosis. These principles have constituted a 'diagnostic modus operandi' for several decades, but the emergence of several new technologies has begun to transform their application.

RECENT FINDINGS

The widespread availability of high-resolution chest computed tomography, endobronchial ultrasound-guided transbronchial needle aspiration, rapid on-site cytopathology and to a lesser degree, fluorodeoxyglucose positron emission tomography have facilitated more convenient diagnosis. They also have identified possibilities for biopsy-less diagnosis in appropriate clinical contexts, similar to idiopathic pulmonary fibrosis, and allowed for more comprehensive assessment of the extent and activity of disease. Nonetheless, these new technologies cannot replace the central role of the clinician, whose judgment and circumspection are keys to accurate diagnosis.

SUMMARY

The diagnosis of sarcoidosis and the assessment of its extent should be tailored to the clinical situation. The application of new technologies may permit some evolution of the diagnostic approach in many patients.

slan-defined subsets of CD16-positive monocytes: impact of granulomatous inflammation and M-CSF receptor mutation

Human monocytes are subdivided into classical, intermediate, and nonclassical subsets, but there is no unequivocal strategy to dissect the latter 2 cell types. We show herein that the cell surface marker 6-sulfo LacNAc (slan) can define slan-positive CD14(+)CD16(++) nonclassical monocytes and slan-negative CD14(++)CD16(+) intermediate monocytes. Gene expression profiling confirms that slan-negative intermediate monocytes show highest expression levels of major histocompatibility complex class II genes, whereas a differential ubiquitin signature is a novel feature of the slan approach. In unsupervised hierarchical clustering, the slan-positive nonclassical monocytes cluster with monocytes and are clearly distinct from CD1c(+) dendritic cells. In clinical studies, we show a selective increase of the slan-negative intermediate monocytes to >100 cells per microliter in patients with sarcoidosis and a fivefold depletion of the slan-positive monocytes in patients with hereditary diffuse leukoencephalopathy with axonal spheroids (HDLS), which is caused by macrophage colony-stimulating factor (M-CSF) receptor mutations. These data demonstrate that the slan-based definition of CD16-positive monocyte subsets is informative in molecular studies and in clinical settings.

Anti-TNF therapeutics for the treatment of sarcoidosis

Sarcoidosis is a systemic disease with an incidence of 1 to 40 per 100 000 persons per year. It predominantly affects people in the age of 20 to 40 years old. Disease course varies from mild self-limiting to chronic debilitating and life-threatening disease. Since the cause of sarcoidosis is unknown, curative therapy is not available. Immunosuppressive drugs may, however, control the symptoms of the disease. The hallmark of sarcoidosis is the formation of granulomas that are most commonly found in lungs and lymph nodes. As TNF plays an important role in both formation and maintenance of these granulomas, as well as in the immune response, anti-TNF biologicals such as infliximab and adalimumab are considered a last resort therapeutic option. Clinical effectiveness, however, varies considerably and data showing which patients would benefit most from this expensive therapy are scarce. This review summarizes current knowledge on anti-TNF therapeutics in sarcoidosis, and describes insights on prediction of response, outcome measures and antibody development.