Phenotypes of organ involvement in sarcoidosis

IgG4-related disease and other fibro-inflammatory conditions

IgG4-related disease (IgG4-RD) is a fibro-inflammatory disorder usually characterized by multi-organ involvement. Its pathogenesis is complex and involves genetic and environmental factors, while immune responses usually mediate organ damage and promote fibrosis, which is a key feature of the disease. IgG4 responses, however, are not exclusive to IgG4-RD and can be encountered in other diseases with phenotypes that partially overlap that of IgG4-RD. Although IgG4-RD has clinical and histological hallmarks, the lack of validated diagnostic criteria often makes the diagnosis challenging, requiring a multi-dimensional approach that integrates clinical, radiological and serological data. The present Review covers recent advances in the understanding of disease drivers and its clinical phenotypes, mainly focusing on the differential diagnosis with potential IgG4-RD mimickers, namely histiocytoses, lymphoproliferative disorders, systemic vasculitides and other immune-mediated conditions. The Review also provides a schematic approach to IgG4-RD treatment, including a brief overview of glucocorticoid-sparing agents and emerging therapies, from B cell-depleting monoclonal antibodies to cytokine-targeting drugs, the majority of which are currently under investigation in randomized clinical trials.

Acute Myocarditis and Inflammatory Cardiomyopathies: Insights From Cardiac Magnetic Resonance Findings

Myocardial inflammation encompasses a broad spectrum of conditions, including acute myocarditis, chronic inflammatory cardiomyopathy, and several overlapping entities that differ in clinical presentation, pathophysiology, and progression. These conditions range from self-limiting acute inflammation to chronic myocardial injury and dysfunction. The etiologic classification of myocardial inflammation highlights the complexity of its pathogenesis, involving direct tissue damage, immune-mediated mechanisms, and environmental triggers. Cardiac magnetic resonance (CMR) imaging has become a central diagnostic tool in the assessment of myocardial inflammation, providing precise characterization of myocardial tissue, assessing cardiac function, and stratifying prognosis. Advanced techniques such as T1 and T2 mapping and extracellular volume quantification have further expanded its diagnostic capabilities. This review highlights the essential role of CMR in diagnosing myocardial inflammation, recognizing various imaging findings associated with different underlying causes, and informing clinical management. The standardization of CMR protocols, along with advancements in imaging techniques and strengthened interdisciplinary collaboration, represents a fundamental step toward improving diagnostic accuracy, patient outcomes, and the understanding of the broad spectrum of myocardial inflammatory diseases.

Phenotypes and Endotypes in Sarcoidosis: Unraveling Prognosis and Disease Course

Sarcoidosis is a multi-system granulomatous disease of unknown etiology. In genetically susceptible individuals, the precipitating factors generate, via immunity mechanisms, a host granulomatous response. The granuloma, for unknown reasons thus far, may resolve or may persist and lead to organ damage and fibrosis. Infectious agents, occupational exposure, obesity, smoking and genetic factors are implicated in the pathogenesis of sarcoidosis. Macrophages are important in granuloma formation, and their M1/M2 phenotype is associated with the prognosis of the disease. CD4+ T helper cells play a central role in the pathogenesis of sarcoidosis. The major contributors appear to be Th1 and Th17.1 cells, whose microenvironmental behavior is dictated by the secretions of macrophages and dendritic cells. Higher levels of Th1 and Th17.1 cells are associated with chronic disease and resistance to corticosteroid treatment. In recent years, advances in the phenotyping of sarcoidosis with the help of HRCT, PET-CT and lung function tests have provided us with a better understanding of the disease. Genetic phenotyping performed by the GenPhenReSa consortium and the SAGA study has led to the recognition of new, distinct phenotypes. The reconstitution of dysregulated autophagy through persistent m-TORC-1 pathways may be a new treatment target in sarcoidosis.

Proteome-wide mendelian randomization identifies causal plasma proteins in interstitial lung disease

Interstitial lung disease (ILD) has shown limited treatment advancements, with minimal exploration of circulating protein biomarkers causally linked to ILD and its subtypes beyond idiopathic pulmonary fibrosis (IPF). In this study, we aimed to identify potential drug targets and circulating protein biomarkers for ILD and its subtypes. We utilized the most recent large-scale plasma protein quantitative trait loci (pQTL) data detected from the antibody-based method and ILD and its subtypes' GWAS data from the updated FinnGen database for Mendelian randomization analysis. To enhance the reliability of causal associations, we conducted external validation and sensitivity analyses, including Bayesian colocalization and bidirectional Mendelian randomization analysis. Our study identified eight plasma proteins genetically associated with ILD or its subtypes. Among these, three proteins-CDH15 (Cadherin-15), LTBR (Lymphotoxin-beta receptor), and ADAM15 (A disintegrin and metalloproteinase 15)-emerged as priority biomarkers and potential therapeutic targets, demonstrating more reliable associations by passing a series of sensitivity analyses compared to the others. Based on these findings, we propose for the first time that CDH15, ADAM15, and LTBR hold promise as novel potential circulating protein biomarkers and therapeutic targets for the diagnosis and treatment of ILD, IPF, and sarcoidosis, respectively, especially ADAM15, and these findings have the potential to provide new perspectives for advancing the research on the heterogeneity of ILD.

The textures of sarcoidosis: quantifying lung disease through variograms

Objective. Sarcoidosis is a granulomatous disease affecting the lungs in over 90% of patients. Qualitative assessment of chest CT by radiologists is standard clinical practice and reliable quantification of disease from CT would support ongoing efforts to identify sarcoidosis phenotypes. Standard imaging feature engineering techniques such as radiomics suffer from extreme sensitivity to image acquisition and processing, potentially impeding generalizability of research to clinical populations. In this work, we instead investigate approaches to engineering variogram-based features with the intent to identify a robust, generalizable pipeline for image quantification in the study of sarcoidosis.Approach. For a cohort of more than 300 individuals with sarcoidosis, we investigated 24 feature engineering pipelines differing by decisions for image registration to a template lung, empirical and model variogram estimation methods, and feature harmonization for CT scanner model, and subsequently 48 sets of phenotypes produced through unsupervised clustering. We then assessed sensitivity of engineered features, phenotypes produced through unsupervised clustering, and sarcoidosis disease signal strength to pipeline.Main results. We found that variogram features had low to mild association with scanner model and associations were reduced by image registration. For each feature type, features were also typically robust to all pipeline decisions except image registration. Strength of disease signal as measured by association with pulmonary function testing and some radiologist visual assessments was strong (optimistic AUC ≈ 0.9,p≪0.0001in models for architectural distortion, conglomerate mass, fibrotic abnormality, and traction bronchiectasis) and fairly consistent across engineering approaches regardless of registration and harmonization for CT scanner.Significance. Variogram-based features appear to be a suitable approach to image quantification in support of generalizable research in pulmonary sarcoidosis.

A framework for exclusion of alternative diagnoses in sarcoidosis

Sarcoidosis is a multisystem granulomatous syndrome that arises from a persistent immune response to a triggering antigen(s). There is no "gold standard" test or algorithm for the diagnosis of sarcoidosis, making the diagnosis one of exclusion. The presentation of the disease varies substantially between individuals, in both the number of organs involved, and the manifestations seen in individual organs. These qualities dictate that health care providers diagnosing sarcoidosis must consider a wide range of possible alternative diagnoses, from across a range of presentations and medical specialties (infectious, inflammatory, cardiac, neurologic). Current guideline-based diagnosis of sarcoidosis recommends fulfillment of three criteria: 1) compatible clinical presentation and/or imaging 2) demonstration of granulomatous inflammation by biopsy (when possible) and, 3) exclusion of alternative causes, but do not provide guidance on standardized strategies for exclusion of alternative diagnoses. In this review, we provide a summary of the most common differential diagnoses for sarcoidosis involvement of lung, eye, skin, central nervous system, heart, liver, and kidney. We then propose a framework for testing to exclude alternative diagnoses based on pretest probability of sarcoidosis, defined as high (typical findings with sarcoidosis involvement confirmed in another organ), moderate (typical findings in a single organ), or low (atypical/findings suggesting of an alternative diagnosis). This work highlights the need for informed and careful exclusion of alternative diagnoses in sarcoidosis.

Kidney manifestations of sarcoidosis

Renal involvement is a clinically relevant organ manifestation of sarcoidosis, leading to increased morbidity and complications. Although the exact incidence remains unknown, renal disease is likely to occur in up to one third of all sarcoidosis patients. Every patient with newly diagnosed sarcoidosis should receive a renal work-up and screening for disrupted calcium metabolism. Amid various forms of glomerulonephritis, granulomatous interstitial nephritis is the most common one, but it rarely leads to renal impairment. Histologically, granulomas can be absent. Nephrocalcinosis and nephrolithiasis are frequent forms when hypercalcaemia or hypercalciuria occur. Drugs used for treatment of systemic sarcoidosis can also cause renal damage. Due to its high heterogeneity, renal sarcoidosis can be difficult to treat. Glucocorticoids and various immunosuppressive treatments have been proven to be effective based on case series, but clinical trials are lacking. A treatment guideline for renal sarcoidosis is urgently needed. In this review article, we present an overview of the different forms of renal sarcoidosis and the diagnostic steps to confirm renal involvement; in addition, we provide insights on the management and available treatments. A better understanding regarding the pathogenesis of sarcoidosis is the key for the development of more specific, targeted therapies.

Chronic Sarcoidosis: Diagnostic Difficulties and Search for New Criteria of Inflammatory Activity (A Case Report and Literature Review)

Sarcoidosis is a systemic inflammatory disease with an unknown etiology and a wide range of clinical manifestations. The incidence of sarcoidosis ranges from approximately 1 to 15 cases per 100,000 individuals per year worldwide. The significant variability in clinical presentations and target organs, as well as concomitant diseases, greatly complicates diagnosis. We analyzed articles in PubMed, Scopus, Cochrane Library, and Embase, where databases were searched using the keywords "chronic sarcoidosis", "diagnosis of sarcoidosis", "course of sarcoidosis", "pulmonary sarcoidosis", "cardiac sarcoidosis", "skin sarcoidosis", "neurosarcoidosis", "ocular sarcoidosis", and "autoimmune inflammation". Studies on the course and diagnosis of sarcoidosis with a deep search of ten years were included. In this review, we present an analysis of publications on the course and diagnosis of chronic sarcoidosis, as well as a clinical case. We have noted that the diagnosis of chronic sarcoidosis is particularly difficult due to the lack of specific biomarkers or their combination. The development and introduction of new diagnostic criteria for this disease will contribute to increasing the level of efficiency, not only of the diagnostic complex, but also the prognosis of the development and course of the pathological process. Conclusion: For the most accurate diagnosis and determination of prognosis, the existence of a single immunological or imaging marker with sufficient sensitivity and specificity is necessary.

Three-year delay in diagnosis of pulmonary sarcoidosis due to presence of necrotizing granulomas: a cautionary case report

Diagnosis of pulmonary sarcoidosis can be difficult and strongly dependent on clinical experience, especially when necrotizing granulomas are present. Here we report an individual who, 3 years after onset of symptoms, was definitively diagnosed with pulmonary sarcoidosis based on percutaneous lung biopsy under the guidance of computed tomography, after he failed to receive a specific diagnosis at other tertiary hospitals based on cervical lymph node biopsy and transbronchial needle aspiration under the guidance of endobronchial ultrasonography. After his definitive diagnosis at our medical center, he was given corticosteroids, which led to remission. Clinicians, especially in areas lacking suitably experienced pathologists, should be aware of how to diagnose sarcoidosis in the presence of abundant necrotizing granulomas in order to ensure timely diagnosis.

Sarcoidosis Diagnostic Score (SDS) system: Impact of race, sex, organ involvement and duration of symptoms prior to diagnosis

BACKGROUND

The Sarcoidosis Diagnostic Score (SDS) system has been established for sarcoidosis patients based on the WASOG organ involvement criteria. We evaluated modifications of the SDS system to determine if they improved its the diagnostic accuracy.

METHODS

Biopsy-confirmed patients with sarcoidosis seen during a 7-month period at 9 sarcoidosis centers across the world. Patients with non-sarcoidosis seen at the same sites were served as control patients. Comparing the SDS-biopsy and SDS-clinical values of five groups: duration of symptoms prior to evaluation (≤1 years vs.>1 years, ≤2 years vs.>2 years), organ involvement (lung, eye, or cardiac), race, and sex.

RESULTS

A total of 990 patients with sarcoidosis and 1011 controls were included in this study. The SDS-clinical was significantly more discriminating for those undergoing assessment with symptoms for more than one year (z-statistic=2.570, p = 0.0102) or two years (z-statistic=2.546, p = 0.0109). However, the addition of two points for both >1 years and >2 years since onset of symptoms did not increase sensitivity and specificity of diagnosis with the SDS system. The SDS-clinical cut-off for patients with ocular or cardiac disease was two points higher than that for lung disease. There was no difference in SDS-clinical or biopsy AUC values based on gender or race.

CONCLUSIONS

The longer the duration of symptoms prior to diagnosis, the more likely the diagnosis of sarcoidosis was correct. For patients presenting with ocular or cardiac symptoms, evidence of multi-organ involved can improve the diagnostic accuracy of the SDS-clinical.

Pulmonary sarcoidosis: differences in lung function change over time

INTRODUCTION

Given the heterogeneity of sarcoidosis, predicting disease course of patients remains a challenge. Our aim was to determine whether the 3-year change in pulmonary function differed between pulmonary function phenotypes and whether there were differential longitudinal changes by race and sex.

METHODS

We identified individuals seen between 2005 and 2015 with a confirmed diagnosis of sarcoidosis who had at least two pulmonary function test measurements within 3 years of entry into the cohort. For each individual, spirometry, diffusion capacity, Charlson Comorbidity Index, sarcoidosis organ involvement, diagnosis duration, tobacco use, race, sex, age and medications were recorded. We compared changes in pulmonary function by type of pulmonary function phenotype and for demographic groups.

RESULTS

Of 291 individuals, 59% (173) were female and 54% (156) were black. Individuals with restrictive pulmonary function phenotype had significantly greater 3-year rate of decline of FVC% (forced vital capacity) predicted and FEV1% (forced expiratory volume in 1 s) predicted course when compared with normal phenotype. We identified a subset of individuals in the cohort, highest decliners, who had a median 3-year FVC decline of 156 mL. Black individuals had worse pulmonary function at entry into the cohort measured by FVC% predicted, FEV1% predicted and diffusing capacity for carbon monoxide % predicted compared with white individuals. Black individuals' pulmonary function remained stable or declined over time, whereas white individuals' pulmonary function improved over time. There were no sex differences in rate of change in any pulmonary function parameters.

SUMMARY

We found significant differences in 3-year change in pulmonary function among pulmonary function phenotypes and races, but no difference between sexes.

Etiological Diagnosis of Uveitis: Contribution of the of the Extra-Ophthalmological Clinical Examination

PURPOSE

Determining uveitis etiology is a challenge. It is based primarily on demographic data and the characteristics of eye examination. It is not clear to what extent extraocular physical signs contribute to elucidating the etiology. This study aimed to establish the contribution of the clinical extra-ophthalmological features for the assessment of the underlying etiology of uveitis.

METHODS

We retrospectively reviewed 1307 patients with uveitis referred to our tertiary center between 2003 and 2021. Uveitis was classified according to the Standardization of Uveitis Nomenclature. Clinical features were collected at diagnosis by internists before the etiological diagnosis was made. The main outcome description was the contribution of clinical features.

RESULTS

Clinical extra-ophthalmological features contributed to the assessment of the underlying etiology of uveitis in 363 (27.8%) patients. The joint and the skin examinations were the most useful for etiological investigations, respectively in 12.3% and 11.8% of patients. Five etiologies of uveitis accounted for 80% of the cases: sarcoidosis, HLA-B27-related uveitis, Behçet's disease, multiple sclerosis, and Vogt-Koyanagi-Harada disease. Clinical extra-ophthalmological features were particularly important in the etiological diagnosis of acute bilateral anterior uveitis and panuveitis.

CONCLUSION

This study suggests that clinical extra-ophthalmological features are essential for the etiological diagnosis of uveitis in more than a quarter of patients. It demonstrates once again the value of collaboration between ophthalmologists and other specialists experienced in performing extra-ophthalmological clinical examinations, particularly in patients with acute bilateral anterior uveitis and panuveitis.

Certolizumab-induced sarcoidosis in a patient with psoriatic arthritis - a case report and review of literature

Tumour necrosis factor-α (TNF- α) antagonists are considered a significant therapeutic option in the treatment of sarcoidosis. Nevertheless, their use can also paradoxically result in sarcoidosis-like reactions. Here, we present a case of a 56-year-old patient with psoriatic arthritis who after 3 months of certolizumab therapy developed pulmonary sarcoidosis. Therefore, certolizumab was discontinued and prednisone initiated. Subsequently, 4 months later a complete remission of interstitial lesions was observed. Due to insufficient control of psoriatic arthritis, upadacitinib and methotrexate were prescribed and despite initial improvement, a couple of months later a massive exacerbation of skin psoriasis occurred and the treatment was switched to secukinumab. As of today, no evidence of sarcoidosis recurrence has been noted. Drug-induced sarcoidosis-like reactions (DISR) appear to be less frequently associated with certolizumab rather than with other anti-TNF-α agents. However, specific mechanisms of this phenomenon remain unclear and require future investigation.

[Position paper of the Austrian Society for Rheumatology and the Austrian Society for Pneumology on the diagnosis and treatment of sarcoidosis 2024]

In many cases sarcoidosis is a multisystemic disease that requires interdisciplinary medical cooperation in the diagnostics, treatment and medical care during follow-up. Due to the often chronic course, it is of utmost importance to include patients with their priorities and wishes at an early stage and extensively in disease management and to establish a shared decision making whenever possible. In the process of writing this joint position paper, the expert group on interstitial and orphan lung diseases of the Austrian Society for Pulmonology and the working group on rheumatological lung disorders of the Austrian Society for Rheumatology and Rehabilitation sought to include patient advocacy groups as well as experts for rare organ manifestations of sarcoidosis. This position paper is not only meant to reflect current scientific and clinical standards but should also focus the national expertise and by networking and exchange to be a first step to strengthen cooperation between stakeholders to ultimately improve care for patients with sarcoidosis.

Can FDG-PET Imaging Identify Cardiac Sarcoidosis Disease Phenotypes?

PURPOSE OF REVIEW

Despite the scarcity of data, most guidelines have advocated for the treatment of cardiac sarcoidosis with corticosteroids. However, there is heterogeneity in disease presentation and response to treatment, which can make treatment challenging. The ability to identify disease phenotypes to allow for tailored therapy is therefore highly desirable. This review will seek to outline the disease phenotypes of cardiac sarcoidosis and the role that FDG-PET imaging can play in identifying these phenotypes to optimize disease diagnosis and treatment management.

RECENT FINDINGS

FDG PET can identify cardiac sarcoidosis and is being increasingly used to monitor therapeutic response to immunosuppressive therapy, to follow treatment response after discontinuation of corticosteroid therapy, and to evaluate for disease relapse. Modern quantitative techniques using FDG PET imaging may allow for even better phenotypic disease characterization and the ability to track the response to immunosuppression more accurately. FDG PET currently plays an important role in cardiac sarcoidosis diagnosis. However, it also affords us the opportunity to offer insights into cardiac sarcoidosis disease phenotypes to better understand the underlying disease process and in the future may allows us to tailor therapies accordingly.

Leveraging AI technology in sarcoidosis

PURPOSE OF REVIEW

Sarcoidosis is a systemic, granulomatous disease of uncertain cause. Diagnosis may be difficult, prognosis uncertain and response to treatment unpredictable. The application of artificial intelligence to sarcoidosis may provide clinical decision support for these challenges. This review will provide an overview of current and potential future applications of artificial intelligence in sarcoidosis.

RECENT FINDINGS

The predominant application of artificial intelligence in sarcoidosis is imaging. Imaging models may differentiate sarcoidosis from other pulmonary disorders. Models, which predict survival and identify key factors relevant to prognosis are also available. The application of cluster analysis to organize sarcoidosis patients into developmental phenotypes is underway. Machine learning algorithms to evaluate the treatment response of sarcoidosis patients do not yet exist but similar models may evaluate patients with other inflammatory disease. The potential applications of artificial intelligence to sarcoidosis is vast, but there are practical limitations that warrant consideration. These include: the accessibility of data, biases in data, cost and privacy.

SUMMARY

The application of artificial intelligence in medicine is still in its early stages but models are poised to support the diagnostic and prognostic challenges in sarcoidosis patients. The predictive power of these artificial intelligence is likely to come from combining various models, trained on content-rich datasets from phenotypically heterogeneous sarcoidosis patients.

A Comprehensive Review on the Electrocardiographic Manifestations of Cardiac Sarcoidosis: Patterns and Prognosis

PURPOSE OF REVIEW

Cardiac sarcoidosis (CS) refers to cardiac involvement in sarcoidosis and is usually associated with worse outcomes. This comprehensive review aims to elucidate the electrocardiographic (ECG) signs and features associated with CS, as well as examine modern techniques and their importance in CS evaluation.

RECENT FINDINGS

The exact pathogenesis of CS is still unclear, but it stems from an abnormal immunological response triggered by environmental factors in individuals with genetic predisposition. CS presents with non-cardiac symptoms; however, conduction system abnormalities are common in patients with CS. The most common electrocardiographic (ECG) signs include atrioventricular blocks and ventricular tachyarrhythmia. Distinct patterns, such as fragmented QRS complexes, T-wave alternans, and bundle branch blocks, are critical indicators of myocardial involvement. The application of advanced ECG techniques such as signal-averaged ECG, Holter monitoring, wavelet-transformed ECG, microvolt T-wave alternans, and artificial intelligence-supported analysis holds promising outcomes for opportune detection and monitoring of CS. Timely utilisation of inexpensive and readily available ECG possesses the potential to allow early detection and intervention for CS. The integration of artificial intelligence models into ECG analysis is a promising approach for improving the ECG diagnostic accuracy and further risk stratification of patients with CS.

Big data in sarcoidosis

PURPOSE OF REVIEW

This review provides an overview of recent advancements in sarcoidosis research, focusing on collaborative networks, phenotype characterization, and molecular studies. It highlights the importance of collaborative efforts, phenotype characterization, and the integration of multilevel molecular data for advancing sarcoidosis research and paving the way toward personalized medicine.

RECENT FINDINGS

Sarcoidosis exhibits heterogeneous clinical manifestations influenced by various factors. Efforts to define sarcoidosis endophenotypes show promise, while technological advancements enable extensive molecular data generation. Collaborative networks and biobanks facilitate large-scale studies, enhancing biomarker discovery and therapeutic protocols.

SUMMARY

Sarcoidosis presents a complex challenge due to its unknown cause and heterogeneous clinical manifestations. Collaborative networks, comprehensive phenotype delineation, and the utilization of cutting-edge technologies are essential for advancing our understanding of sarcoidosis biology and developing personalized medicine approaches. Leveraging large-scale epidemiological resources and biobanks and integrating multilevel molecular data offer promising avenues for unraveling the disease's heterogeneity and improving patient outcomes.

Beyond biopsy for neurosarcoidosis: A review of blood and CSF biomarkers

Neurosarcoidosis, a rare granulomatous disease, causes inflammation and damage to the central nervous system (CNS). A major diagnostic challenge in neurosarcoidosis is the absence of well-defined biomarkers. The need for biopsy to make the diagnosis can lead to delays and misdiagnosis if histopathology is inaccessible or indeterminate, highlighting the need for more accessible diagnostic indicators. The current gold standard for a "definite" neurosarcoidosis diagnosis requires biopsy of CNS tissue revealing non-caseating granulomas. However, such biopsies are inherently invasive and carry associated procedural risks. Notably, angiotensin-converting enzyme (ACE), commonly associated with systemic sarcoidosis, is recognized as a poor biomarker for neurosarcoidosis due to its lack of accuracy in the context of CNS involvement. Furthermore, imaging in neurosarcoidosis, while widely utilized and important for narrowing the diagnosis, lacks specificity. Decades of research have yielded molecular and immunologic biomarkers-soluble interleukin-2 receptor (IL-2R), serum amyloid A1, the CD4/CD8 ratio, neopterin, interferon-gamma (IFN-γ), and chemokine ligand 2 (CCL2)-that hold potential for improving diagnostic accuracy. However, these biomarkers are not yet established in clinical care as they may be difficult to obtain and are derived from small studies. They also suffer from a lack of specificity against other inflammatory and infectious central nervous system diseases. New biomarkers are needed for use alongside those previously discovered to improve diagnosis of this rare disease. This review synthesizes existing literature on neurosarcoidosis biomarkers, aiming to establish a foundation for further research in this evolving field. It also consolidates information on biomarkers of systemic sarcoidosis such as IL-8 and soluble CD40L that have not yet been studied in neurosarcoidosis but hold potential as markers of CNS disease.

Role of triglyceride-glucose index in metabolic assessment of sarcoidosis patients

Sarcoidosis is a rare granulomatous disease that can affect any organ. It leads to an increased risk of metabolic syndrome and insulin resistance, due to biochemical pathways involved in low-grade inflammation in both diseases. The aim of our retrospective case-control study was to evaluate the utility of triglyceride-glucose (TyG) index, a surrogate of insulin resistance, for metabolic assessment of sarcoidosis patients. A cohort of 90 sarcoidosis patients and a cohort of 90 control subjects were enrolled. Clinical, anamnestic, and biochemical data were collected. Results showed that TyG index values were higher in the sarcoidosis cohort than in the control group (p < 0.001), even after excluding the influence of diabetes and metabolic syndrome (p = 0.018). In the sarcoidosis cohort, TyG index was not correlated with clinical phenotyping (p = 0.358), gender (p = 0.139), radiological stage (p = 0.656), glucocorticoids cumulative dose (p = 0.682) or treatment regimen (p = 0.093), while significant positive correlations with waist circumference (p < 0.001), systolic and diastolic pressure (p = 0.041 and p = 0.029, respectively), Framingham score (p = 0.007) were found. Receiving operating characteristics curve analysis identified a TyG index optimal cut-off value of 8.64 (66.7% sensitivity, 77.8% specificity, area under the curve -AUC- 75%, 95% confidence interval -CI- 65-85, p < 0.001) to detect metabolic syndrome and a cut-off value of 8.69 (64.1% sensitivity, 70.6% specificity; AUC 67%, 95% CI 55-78, p = 0.007) to detect an intermediate cardiovascular risk according to Framingham risk score. Concluding, TyG index can be considered a useful tool for the metabolic assessment of sarcoidosis patients, given its capacity to predict metabolic syndrome and cardiovascular risk.

Extremely Unusual Coronary Involvement in Cardiac Sarcoidosis

Left ventricular (LV) regional wall motion abnormalities are common in cardiac sarcoidosis but coronary occlusion is very rare. Here, we report a case of cardiac sarcoidosis with very unusual coronary involvement. A 43-year-old man presented with a persistent cough and a history of uveitis 6 months back with no other comorbidities. He was initially treated with empirical antitubercular treatment but continued to have an intractable cough and hence, underwent further evaluation. Echocardiography revealed global LV systolic dysfunction with inferior wall akinesia and LV ejection fraction 25%-30%. Cardiac magnetic resonance imaging confirmed these findings. It also showed subendocardial late gadolinium enhancement localized to the inferior wall segments with 50%-75% transmural extent. 18-fluorodeoxyglucose (FDG) positron emission tomography showed multiple FDG-avid lymph nodes all over the body along with intense myocardial FDG uptake confined to the inferior wall. Coronary angiography was performed which showed double-vessel disease with critical stenosis of the right coronary artery (RCA). Ultrasonography-guided fine-needle aspiration cytology from inguinal lymph nodes showed nonnecrotizing granulomas without any evidence of tuberculosis. He was started on steroids and appropriate heart failure medications and underwent percutaneous transluminal coronary angioplasty with stent to RCA. Later, he presented with hemodynamically stable ventricular tachycardia and received an implantable cardioverter defibrillator.

The textures of sarcoidosis: quantifying lung disease through variograms

Objective

Sarcoidosis is a granulomatous disease affecting the lungs in over 90% of patients. Qualitative assessment of chest CT by radiologists is standard clinical practice and reliable quantification of disease from CT would support ongoing efforts to identify sarcoidosis phenotypes. Standard imaging feature engineering techniques such as radiomics suffer from extreme sensitivity to image acquisition and processing, potentially impeding generalizability of research to clinical populations. In this work, we instead investigate approaches to engineering variogram-based features with the intent to identify a robust, generalizable pipeline for image quantification in the study of sarcoidosis.

Approach

For a cohort of more than 300 individuals with sarcoidosis, we investigated 24 feature engineering pipelines differing by decisions for image registration to a template lung, empirical and model variogram estimation methods, and feature harmonization for CT scanner model, and subsequently 48 sets of phenotypes produced through unsupervised clustering. We then assessed sensitivity of engineered features, phenotypes produced through unsupervised clustering, and sarcoidosis disease signal strength to pipeline.

Main results

We found that variogram features had low to mild association with scanner model and associations were reduced by image registration. For each feature type, features were also typically robust to all pipeline decisions except image registration. Strength of disease signal as measured by association with pulmonary function testing and some radiologist visual assessments was strong (optimistic AUC ≈ 0.9, p ≪ 0.0001 in models for architectural distortion, conglomerate mass, fibrotic abnormality, and traction bronchiectasis) and fairly consistent across engineering approaches regardless of registration and harmonization for CT scanner.

Significance

Variogram-based features appear to be a suitable approach to image quantification in support of generalizable research in pulmonary sarcoidosis.

Comparison of organ involvement clusters in Black and White American sarcoidosis patients from a prospectively collected patient registry

BACKGROUND

Due to the heterogeneity of sarcoidosis, there is a need to define clinical phenotypes to allow for tailoring of clinical care and identification of more homogenous populations to facilitate research.

METHODS

We utilized data from a prospectively collected registry of sarcoidosis patients seen at a single quaternary referral center between January 2019 and February 2021. We used multiple correspondence analysis (MCA) and k-means clustering to investigate if the clusters previously identified in the GenPhenReSa study were reproducible in a US population. We also investigated if these clusters were stable when the population was stratified by race.

RESULTS

We replicated 3 of the 5 clusters seen in the GenPhenReSa study in our cohort. We likewise identified similar clusters between White and Black patients with sarcoidosis. Differences in organ manifestations associations between White and Black patients were seen primarily in relation to cardiac, neurologic, and ocular involvement.

CONCLUSIONS

The organ clusters of liver-spleen, isolated pulmonary, and musculoskeletal-skin were reproducible in a US cohort, and in both Black and White patients.

Organ involvement in newly diagnosed sarcoidosis patients in the Netherlands: The first large European multicentre prospective study

BACKGROUND

Clinical presentation and prevalence of organ involvement is highly variable in sarcoidosis and depends on ethnic, genetic and geographical factors. These data are not extensively studied in a Dutch population.

AIM

To determine the prevalence of organ involvement and the indication for systemic immunosuppressive therapy in newly diagnosed sarcoidosis patients in the Netherlands.

METHODS

Two large Dutch teaching hospitals participated in this prospective cohort study. All adult patients with newly diagnosed sarcoidosis were prospectively included and a standardized work-up was performed. Organ involvement was defined using the WASOG instrument.

RESULTS

Between 2015 and 2020, a total of 330 patients were included, 55% were male, mean age was 46 (SD 14) years. Most of them were white (76%). Pulmonary involvement including thoracic lymph node enlargement was present in 316 patients (96%). Pulmonary parenchymal disease was present in 156 patients (47%). Ten patients (3%) had radiological signs of pulmonary fibrosis. Cutaneous sarcoidosis was present in 74 patients (23%). Routine ophthalmological screening revealed uveitis in 29 patients (12%, n = 256)). Cardiac and neurosarcoidosis were diagnosed in respectively five (2%) and six patients (2%). Renal involvement was observed in 11 (3%) patients. Hypercalcaemia and hypercalciuria were observed in 29 (10%) and 48 (26%, n = 182) patients, respectively. Hepatic involvement was found in 6 patients (2%). In 30% of the patients, systemic immunosuppressive treatment was started at diagnosis.

CONCLUSIONS

High-risk organ involvement in sarcoidosis is uncommon at diagnosis. Indication for systemic immunosuppressive therapy was present in a minority of patients.

Phenotypes and Serum Biomarkers in Sarcoidosis

Sarcoidosis is a multisystem disease, which is diagnosed on a compatible clinical presentation, non-necrotizing granulomatous inflammation in one or more tissue samples, and exclusion of alternative causes of granulomatous disease. Considering its heterogeneity, numerous aspects of the disease remain to be elucidated. In this context, the identification and integration of biomarkers may hold significance in clinical practice, aiding in appropriate selection of patients for targeted clinical trials. This work aims to discuss and analyze how validated biomarkers are currently integrated in disease category definitions. Future studies are mandatory to unravel the diverse contributions of genetics, socioeconomic status, environmental exposures, and other sociodemographic variables to disease severity and phenotypic presentation. Furthermore, the implementation of transcriptomics, multidisciplinary approaches, and consideration of patients' perspectives, reporting innovative insights, could be pivotal for a better understanding of disease pathogenesis and the optimization of clinical assistance.

Cardiac Involvement in Neurosarcoidosis: A Single-Center Investigation

BACKGROUND AND OBJECTIVES

Sarcoidosis is a multisystem inflammatory granulomatous disease. Among systemic sarcoidosis manifestations, cardiac or nervous system involvement can result in significant morbidity and mortality. We describe the overlapping incidence of cardiac sarcoidosis (CS) within a neurosarcoidosis (NS) cohort and determine the frequency of other nonsarcoid cardiac diseases in these patients.

METHODS

We performed a retrospective chart review of patients evaluated at the University of Utah from 2010 to 2022. Patients were included if they had (1) at least one instance of a diagnostic code for sarcoidosis in their medical record-International Classification of Diseases (ICD) 9 code 135 or ICD 10 code D86; (2) at least one outpatient visit in the Neurology Department within the University of Utah electronic health record with a diagnosis of definite, probable, or possible NS based on 2018 consensus criteria; (3) at least one outpatient visit in the Cardiology Department within the University of Utah electronic health record; and (4) ECG available in their medical record for review. Of 64 definite, probable, or possible patients with NS in the University of Utah cohort, 52 met our inclusion criteria and were included in this study.

RESULTS

Of 52 patients with NS who met our inclusion criteria, 65.38% were female, with an average age of 60.9 years (range 38-84). More than half (58%) were obese (BMI ≥ 30). CS was diagnosed in 6 patients with NS (12%). Symptoms suggestive of possible cardiac dysfunction included lower extremity edema (50%), palpitations (46%), chest pain (44%), and shortness of breath (27%). ECG abnormalities included nonspecific T-wave change (40%) and right bundle branch block (17%). Three patients experienced ventricular tachycardia: sustained in one patient and nonsustained in 2 patients. Cardiac MRI was performed in 17 patients (32.7%) and in 3 patients (17.6%), which revealed diffuse myocardial enhancement suggesting CS.

DISCUSSION

In this cohort, 12% of patients with NS also had confirmed CS. In addition, these patients had a high burden of cardiovascular disease not directly attributed to sarcoidosis. Our data suggest that patients with NS require comprehensive cardiac evaluation. Future studies are needed to clarify the extent of the direct contribution of granulomatous inflammation on the cardiovascular system from the indirect contribution of treatments such as glucocorticoids that lead to increased risk of cardiovascular disease in sarcoidosis.

Cardiac Sarcoidosis

Cardiac involvement is a major cause of morbidity and mortality in patients with sarcoidosis. It is important to distinguish between clinical manifest diseases from clinically silent diseases. Advanced cardiac imaging studies are crucial in the diagnostic pathway. In suspected isolated cardiac sarcoidosis, it's key to rule out alternative diagnoses. Therapeutic options can be divided into immunosuppressive agents, guideline-directed medical therapy, antiarrhythmic medications, device/ablation therapy, and heart transplantation.

Ocular Sarcoidosis

Sarcoidosis frequently affects the eye and can do so in many different ways. Sarcoidosis causing uveitis can have distinctive features that facilitate identifying sarcoidosis as the cause of the uveitis. Progress is being made in elucidating ocular sarcoidosis, as for example, by transcriptomics, genetics, therapy, and imaging.

Extra-pulmonary Cutaneous Sarcoidosis Presenting With Granulomatous Cranial Lesions and Cardiac Complications: A Case Report

Sarcoidosis is a non-caseating granulomatous disorder affecting multiple organs. Although the lungs are the most common site of presentation, extra-pulmonary manifestations involving the skin and heart can occur. Sarcoidosis affecting skull bone is uncommon and involvement of skin, heart, and skull bone all together, without pulmonary manifestations, is extremely rare. We report a 63-year-old Caucasian woman with a past history of cutaneous sarcoidosis and granulomatous skull bone lesions who presented with recurrent syncope. An ambulatory cardiac monitor detected intermittent high-grade atrioventricular block and cardiac MRI confirmed the diagnosis of cardiac sarcoidosis. This case represents an extremely unique journey of sarcoidosis and suggests potential consideration for cardiac sarcoidosis screening in patients with a history of extra-cardiac manifestations.

Advances in cellular and tissue-based imaging techniques for sarcoid granulomas

Sarcoidosis embodies a complex inflammatory disorder spanning multiple systems, with its origin remaining elusive. It manifests as the infiltration of inflammatory cells that coalesce into distinctive noncaseous granulomas within afflicted organs. Unraveling this disease necessitates the utilization of cellular or tissue-based imaging methods to both visualize and characterize the biochemistry of these sarcoid granulomas. Although hematoxylin and eosin stain, standard in routine use alongside cytological stains have found utility in diagnosis within clinical contexts, special stains such as Masson's trichrome, reticulin, methenamine silver, and Ziehl-Neelsen provide additional varied perspectives of sarcoid granuloma imaging. Immunohistochemistry aids in pinpointing specific proteins and gene expressions further characterizing these granulomas. Finally, recent advances in spatial transcriptomics promise to divulge profound insights into their spatial orientation and three-dimensional (3-D) molecular mapping. This review focuses on a range of preexisting imaging methods employed for visualizing sarcoid granulomas at the cellular level while also exploring the potential of the latest cutting-edge approaches like spatial transcriptomics and matrix-assisted laser desorption ionization mass spectrometry imaging (MALDI-MSI), with the overarching goal of shedding light on the trajectory of sarcoidosis research.

Clinical manifestations and associated factors of uveitis in patients with pulmonary sarcoidosis: a case control study

Sarcoidosis, an idiopathic and inflammatory disease, affects various organs and can manifest as uveitis. Due to limited evidence, researchers investigated the risk factors associated with uveitis in patients with pulmonary sarcoidosis. A retrospective study was conducted on 71 pulmonary sarcoidosis patients, including 19 with uveitis and 52 without. Data on involved organs, imaging findings, spirometry, and analyses from blood and bronchoalveolar lavage fluid were collected. Logistic regression models were used for multivariate analysis. Among the 71 newly diagnosed pulmonary sarcoidosis patients, uveitis was observed in 19 patients (26.8%). No significant differences were found in clinical characteristics between patients with and without uveitis. Fewer patients with uveitis presented lung parenchymal lesions (P = 0.043). In multivariate analysis, skin lesions (aOR 7.619, 95% CI 1.277-45.472, P = 0.026) and ophthalmic symptoms (aOR 4.065, 95% CI 1.192-13.863, P = 0.025) were associated with uveitis. Absence of uveitis was related to lung parenchymal lesions (aOR 0.233, 95% CI 0.062-0.883, P = 0.032). Approximately one-quarter of patients with an initial diagnosis of pulmonary sarcoidosis were diagnosed with uveitis. Presence of skin lesions, ophthalmic symptoms, and absence of lung parenchymal lesions were related to uveitis. These results need to be clarified by further studies to confirm the clinical role of early ophthalmologic screening for pulmonary sarcoidosis patients with these factors.

Osteoporosis and major fragility fractures (MOF) in sarcoidosis patients: association with disease severity

BACKGROUND

The reports on bone mineral loss or major osteoporosis fracture (MOF) in sarcoidosis are scarce and have conflicting outcomes. This study aimed to evaluate the prevalence and risk factors of MOF in sarcoidosis patients.

METHODS

In a single-center cohort of 382 patients with sarcoidosis (55.8 ± 11.6 years) we evaluated bone mineral density at lumbar spine, at femoral neck and at total hip and the presence of MOF. Lung function measurements including diffusion capacity for carbon monoxide (DLCO) were assessed. Chest X-rays were performed and radiological staging was done by Scadding score.

RESULTS

Ninety patients (23.6%) with sarcoidosis have history of a MOF. BMD T-scores were lower in sarcoidosis with MOF with respect to those without MOF, but the difference was statistically significant only for BMD at femoral neck (p < 0.05). Moreover, BMD values at total hip was positively correlated with DLCO (%) (p < 0.001). Prevalence of MOF was higher in patients with sarcoidosis with lung parenchymal involvement (radiological stages 2-4) than in patients with sarcoidosis in chest X-ray stages 0 and 1 (28.3 vs 19.2% respectively, p < 0.05). Moreover, multiple regression analyses showed that X-ray Scadding score was positively associated with MOF.

CONCLUSIONS

This study shows that MOF represent a common and important complication in patients with moderate/severe sarcoidosis. The chest X-ray evaluation and the pulmonary function test could allow to define the risk of MOF in sarcoidosis patients.

Establishing a Diagnosis of Pulmonary Sarcoidosis

Pulmonary sarcoidosis is the most prevalent manifestation of sarcoidosis and the commonest diagnosis in clinics for ILD. Due to the lack of a simple and reliable test, making the diagnosis is often challenging. There are three criteria that must always be considered: (1) compatible clinical presentation; (2) evidence of granuloma formation (usually non-caseating); and (3) exclusion of alternative causes of granulomatous disease. There are various tools available for diagnosis, amongst which serum biomarkers like sACE and sIL-2R, HRCT, BAL, EBUS/EUS and sometimes bronchoscopic or surgical lung biopsy are most contributive. However, the degree of invasiveness of the applied test and associated risk to the patient must be weighed against management consequences. In specific situations (e.g., presentation as Löfgren's syndrome) or when there is high suspicion based on HRCT in the context of supportive clinical findings, it might be justifiable to decide on a "working diagnosis of sarcoidosis" and to refrain from further invasive procedures for the patient. This should, however, preferably be agreed upon after discussion in an experienced multidisciplinary team and requires close follow-up of the patient. In general, it is advisable to always maintain a healthy dose of skepticism when making the diagnosis of sarcoidosis, especially when the clinical course of disease gives rise to this.

An mTORC1-Dependent Mouse Model for Cardiac Sarcoidosis

Background Sarcoidosis is an inflammatory, granulomatous disease of unknown cause affecting multiple organs, including the heart. Untreated, unresolved granulomatous inflammation can lead to cardiac fibrosis, arrhythmias, and eventually heart failure. Here we characterize the cardiac phenotype of mice with chronic activation of mammalian target of rapamycin (mTOR) complex 1 signaling in myeloid cells known to cause spontaneous pulmonary sarcoid-like granulomas. Methods and Results The cardiac phenotype of mice with conditional deletion of the tuberous sclerosis 2 (TSC2) gene in CD11c+ cells (TSC2fl/flCD11c-Cre; termed TSC2KO) and controls (TSC2fl/fl) was determined by histological and immunological stains. Transthoracic echocardiography and invasive hemodynamic measurements were performed to assess myocardial function. TSC2KO animals were treated with either everolimus, an mTOR inhibitor, or Bay11-7082, a nuclear factor-kB inhibitor. Activation of mTOR signaling was evaluated on myocardial samples from sudden cardiac death victims with a postmortem diagnosis of cardiac sarcoidosis. Chronic activation of mTORC1 signaling in CD11c+ cells was sufficient to initiate progressive accumulation of granulomatous infiltrates in the heart, which was associated with increased fibrosis, impaired cardiac function, decreased plakoglobin expression, and abnormal connexin 43 distribution, a substrate for life-threatening arrhythmias. Mice treated with the mTOR inhibitor everolimus resolved granulomatous infiltrates, prevented fibrosis, and improved cardiac dysfunction. In line, activation of mTOR signaling in CD68+ macrophages was detected in the hearts of sudden cardiac death victims who suffered from cardiac sarcoidosis. Conclusions To our best knowledge this is the first animal model of cardiac sarcoidosis that recapitulates major pathological hallmarks of human disease. mTOR inhibition may be a therapeutic option for patients with cardiac sarcoidosis.

Current Applications of Artificial Intelligence in Sarcoidosis

PURPOSE

Sarcoidosis is a complex disease which can affect nearly every organ system with manifestations ranging from asymptomatic imaging findings to sudden cardiac death. As such, diagnosis and prognostication are topics of continued investigation. Recent technological advancements have introduced multiple modalities of artificial intelligence (AI) to the study of sarcoidosis. Machine learning, deep learning, and radiomics have predominantly been used to study sarcoidosis.

METHODS

Articles were collected by searching online databases using keywords such as sarcoid, machine learning, artificial intelligence, radiomics, and deep learning. Article titles and abstracts were reviewed for relevance by a single reviewer. Articles written in languages other than English were excluded.

CONCLUSIONS

Machine learning may be used to help diagnose pulmonary sarcoidosis and prognosticate in cardiac sarcoidosis. Deep learning is most comprehensively studied for diagnosis of pulmonary sarcoidosis and has less frequently been applied to prognostication in cardiac sarcoidosis. Radiomics has primarily been used to differentiate sarcoidosis from malignancy. To date, the use of AI in sarcoidosis is limited by the rarity of this disease, leading to small, suboptimal training sets. Nevertheless, there are applications of AI that have been used to study other systemic diseases, which may be adapted for use in sarcoidosis. These applications include discovery of new disease phenotypes, discovery of biomarkers of disease onset and activity, and treatment optimization.

Genetic and geographic influence on phenotypic variation in European sarcoidosis patients

Introduction

Sarcoidosis is a highly variable disease in terms of organ involvement, type of onset and course. Associations of genetic polymorphisms with sarcoidosis phenotypes have been observed and suggest genetic signatures.

Methods

After obtaining a positive vote of the competent ethics committee we genotyped 1909 patients of the deeply phenotyped Genetic-Phenotype Relationship in Sarcoidosis (GenPhenReSa) cohort of 31 European centers in 12 countries with 116 potentially disease-relevant single-nucleotide polymorphisms (SNPs). Using a meta-analysis, we investigated the association of relevant phenotypes (acute vs. sub-acute onset, phenotypes of organ involvement, specific organ involvements, and specific symptoms) with genetic markers. Subgroups were built on the basis of geographical, clinical and hospital provision considerations.

Results

In the meta-analysis of the full cohort, there was no significant genetic association with any considered phenotype after correcting for multiple testing. In the largest sub-cohort (Serbia), we confirmed the known association of acute onset with TNF and reported a new association of acute onset an HLA polymorphism. Multi-locus models with sets of three SNPs in different genes showed strong associations with the acute onset phenotype in Serbia and Lublin (Poland) demonstrating potential region-specific genetic links with clinical features, including recently described phenotypes of organ involvement.

Discussion

The observed associations between genetic variants and sarcoidosis phenotypes in subgroups suggest that gene-environment-interactions may influence the clinical phenotype. In addition, we show that two different sets of genetic variants are permissive for the same phenotype of acute disease only in two geographic subcohorts pointing to interactions of genetic signatures with different local environmental factors. Our results represent an important step towards understanding the genetic architecture of sarcoidosis.

Sex and Race Differences in Cardiac Sarcoidosis Presentation, Treatment and Outcomes

BACKGROUND

Although sex- and race-based patterns have been described in the extracardiac organ involvement of sarcoidosis, cardiac sarcoidosis (CS)-specific studies are lacking.

METHODS

We studied CS presentation, treatment and outcomes based on sex and race in a tertiary-center cohort. Multivariable adjusted Cox proportional hazards and survival analyses were performed for primary composite outcomes (left ventricular assist device, heart transplantation, all-cause death) and for secondary outcomes (ventricular arrhythmia and all-cause death.

RESULTS

We identified 252 patients with CS (108 female, 109 Black). At presentation with CS, females vs males (P = 0.001) and Black vs White individuals (P = 0.001) more commonly had symptomatic heart failure (HF), with HF most common in Black females (ANOVA P < 0.001). Treatment differences included more corticosteroid use (90% vs 79%; P = 0.020), higher 1-year prednisone dosage (13 vs 10 mg; P = 0.003) and less frequent early steroid-sparing agent use in males (29% vs 40%; P = 0.05). Black participants more frequently received a steroid-sparing agent (75% vs 60%; P = 0.023). Composite outcome-free survival did not differ by sex or race. Male sex had an adjusted hazard ratio of 2.34 (95% CI 1.13, 4.80; P = 0.021) for ventricular arrhythmia.

CONCLUSION

CS course may differ by sex and race and may contribute to distinct clinical CS phenotypes.

Occupational lung disease: when should I think of it and why is it important?

Exposure to toxic inhalants in the workplace has the potential to cause (in susceptible individuals) almost any major type of lung disease, such as asthma, COPD and interstitial lung diseases. Patients with occupational lung disease will often present to or will be managed by respiratory specialists without training in occupational respiratory medicine, and patients (or their clinicians) may not identify a link between their disease and their current or a past job. Without an awareness of the range of different occupational lung diseases that exist, their similarity to their non-occupational counterparts, and without directed questioning, these conditions may go unidentified. Patients with occupational lung diseases are often in lower paid work and are disproportionally affected by health inequality. Both clinical and socioeconomic outcomes generally improve if cases are identified early. This allows appropriate advice to be given about the risks of ongoing exposure, clinical management, occupational mobility and, in some cases, eligibility for legal compensation. As respiratory professionals, it is important that these cases are not missed, and if needed, are discussed with a physician with specialised expertise. Here we describe some of the most common occupational lung diseases and outline the diagnostic and treatment approach.

Multiple Correspondence Analysis and HLA-Associations of Organ Involvement in a Large Cohort of African-American and European-American Patients with Sarcoidosis

Sarcoidosis is a systemic granulomatous disease with predominant pulmonary involvement and vast heterogeneity of clinical manifestations and disease outcomes. African American (AA) patients suffer greater morbidity and mortality. Using Multiple Correspondence Analysis, we identified seven clusters of organ involvement in European American (EA; n = 385) patients which were similar to those previously described in a Pan-European (GenPhenReSa) and a Spanish cohort (SARCOGEAS). In contrast, AA (n = 987) had six, less well-defined and overlapping clusters with little similarity to the cluster identified in the EA cohort evaluated at the same U.S. institutions. Association of cluster membership with two-digit HLA-DRB1 alleles demonstrated ancestry-specific patterns of association and replicated known HLA effects.These results further support the notion that genetically influenced immune risk profiles, which differ based on ancestry, play a role in phenotypic heterogeneity. Dissecting such risk profiles will move us closer to personalized medicine for this complex disease.

[Sarcoidosis]

Sarcoidosis is the most common granulomatous disease in northern Europe. A distinction is made between acute forms of sarcoidosis and chronic sarcoidosis. Chronic sarcoidosis can affect practically all organs but the lungs are affected in 90-95% of patients. The clinical appearance varies between asymptomatic and oligosymptomatic courses, which are diagnosed more by chance, to courses with acute organ failure. An extensive organ work-up is necessary at the time of the initial diagnosis in order to record the extent of organ involvement and to make appropriate treatment decisions. Asymptomatic courses with purely pulmonary sarcoidosis do not require treatment and can be observed over the course of the disease, whereas courses with extensive organ involvement or organ dysfunction require treatment. The treatment consists primarily of the administration of glucocorticoids. If the effect of the glucocorticoids is insufficient or if there are side effects, various immunosuppressive agents, including biologics can be added.

From Karl Wurm and Guy Scadding's staging to 18F-FDG PET/CT scan phenotyping and far beyond: perspective in the evading history of phenotyping in sarcoidosis

Sarcoidosis is an inflammatory granulomatous disease of unknown etiology involving any organ or tissue along with any combination of active sites, even the most silent ones clinically. The unpredictable nature of the sites involved in sarcoidosis dictates the highly variable natural history of the disease and the necessity to cluster cases at diagnosis based on clinical and/or imaging common characteristics in an attempt to classify patients based on their more homogeneous phenotypes, possibly with similar clinical behavior, prognosis, outcome, and therefore with therapeutic requirements. In the course of the disease's history, this attempt relates to the availability of a means of detection of the sites involved, from the Karl Wurm and Guy Scadding's chest x-ray staging through the ACCESS, the WASOG Sarcoidosis Organ Assessment Instruments, and the GenPhenReSa study to the 18F-FDG PET/CT scan phenotyping and far beyond to new technologies and/or the current "omics." The hybrid molecular imaging of the 18F-FDG PET/CT scan, by unveiling the glucose metabolism of inflammatory cells, can identify high sensitivity inflammatory active granulomas, the hallmark of sarcoidosis-even in clinically and physiologically silent sites-and, as recently shown, is successful in identifying an unexpected ordered stratification into four phenotypes: (I) hilar-mediastinal nodal, (II) lungs and hilar-mediastinal nodal, (III) an extended nodal supraclavicular, thoracic, abdominal, inguinal, and (IV) all the above in addition to systemic organs and tissues, which is therefore the ideal phenotyping instrument. During the "omics era," studies could provide significant, distinct, and exclusive insights into sarcoidosis phenotypes linking clinical, laboratory, imaging, and histologic characteristics with molecular signatures. In this context, the personalization of treatment for sarcoidosis patients might have reached its goal.

Sarcoidosis-Related Uveitis: A Review

Sarcoidosis is an inflammatory disease that involves the eyes in 10-55% of cases, sometimes without systemic involvement. All eye structures can be affected, but uveitis is the most common ocular manifestation and causes vision loss. The typical ophthalmological appearance of these uveitis is granulomatous (in cases with anterior involvement), which are usually bilateral and with synechiae. Posterior involvement includes vitritis, vasculitis and choroidal lesions. Tuberculosis is a classic differential diagnosis to be wary of, especially in people who have spent time in endemic areas. The diagnosis is based on histology with the presence of non-caseating epithelioid granulomas. However, due to the technical difficulty and yield of biopsies, the diagnosis of ocular sarcoidosis is often based on clinico-radiological features. The international criteria for the diagnosis of ocular sarcoidosis have recently been revised. Corticosteroids remain the first-line treatment for sarcoidosis, but up to 30% of patients require high doses, justifying the use of corticosteroid-sparing treatments. In these cases, immunosuppressive treatments such as methotrexate may be introduced. More recent biotherapies such as anti-TNF are also very effective (as they are in other non-infectious uveitis etiologies).

Comparative Analysis of FCGR Gene Polymorphism in Pulmonary Sarcoidosis and Tuberculosis

The clinical outcome of sarcoidosis (SA) is very similar to tuberculosis (TB); however, they are treated differently and should not be confused. In search for their biomarkers, we have previously revealed changes in the phagocytic activity of monocytes in sarcoidosis and tuberculosis. On these monocytes we found a higher expression of receptors for the Fc fragment of immunoglobulin G (FcγR) in SA and TB patients vs. healthy controls. FcγRs are responsible for the binding of immune complexes (ICs) to initiate an (auto)immune response and for ICs clearance. Surprisingly, our SA patients had a high blood level of ICs, despite the abundant presence of FcγRs. It pointed to FcγR disfunction, presumably caused by the polymorphism of their (FCGR) genes. Therefore, we present here an analysis of the occurrence of FCGR2A, FCGR2B, FCGR2C, FCGR3A and FCGR3B variants in Caucasian SA and TB patients, and healthy individuals with the use of polymerase chain reaction (PCR) and real-time PCR. The presented data point to a possibility of supporting the differential diagnosis of SA and TB by analyzing FCGR2C, FCGR3A and FCGR3B polymorphism, while for severe stages of SA also by studying FCGR2A variants. Additionally, the genotyping of FCGR2A and FCGR3B might serve as a marker of SA progression.

Cardiac sarcoidosis

The diagnostic yield of endomyocardial biopsy in cardiac sarcoidosis (CS) is quite low because of the patchy involvement, and for the diagnosis of CS, existing guidelines required histological confirmation. Therefore, especially for isolated CS, diagnosis consistent with the guidelines cannot be made in a large number of patients. With recent developments in imaging modalities such as cardiac magnetic resonance and 18-fluorodeoxyglucose positron emission tomography, diagnosing CS has become easier and diagnostic criteria for CS not compulsorily requiring histological confirmation have been suggested. Despite significant advances in diagnostic tools, large-scale studies that can guide treatment plans are still lacking, and treatment has relied on the experience accumulated over the past years and the consensus of experts. However, opinions vary, depending on the situation, which is quite puzzling for the physician treating CS. Moreover, with the advent of new immunosuppressant agents, these new drugs have been applied under the assumption that the effect of immunosuppression is not much different from that of other well-known autoimmune diseases that require immunosuppression. However, we should wait to see the beneficial effects of these new immunosuppressants before we attempt to apply these agents in our clinical practice. This review summarises the widely used diagnostic criteria, current diagnostic modalities and recommended treatments for sarcoidosis. We have added our opinions on selecting or modifying diagnostic and treatment plans from the diverse current recommendations.