Occupational causes of 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.

Cutaneous Sarcoidosis Induced by Laser Therapy: Case Report and Review of the Literature

BACKGROUND

Sarcoidosis, characterized by non-caseating epithelioid granulomas, presents diagnostic and therapeutic challenges.

METHOD

Here we present a 38-year-old woman who exhibited erythematous and infiltrated skin lesions on her facial region following fractional laser treatment.

RESULTS

Histological analysis confirmed cutaneous sarcoidosis. Initial interventions with topical clobetasol and oral chloroquine provided transient relief. Subsequent outpatient management comprised topical tacrolimus and clobetasol, as well as systemic methotrexate, later substituted with prednisone. Gradual tapering resulted in lesion reduction.

CONCLUSIONS

This case underscores the intricate nature of cutaneous sarcoidosis and the necessity for personalized therapeutic approaches. The association with cosmetic procedures highlights the importance of understanding potential triggers. The presented case highlights and reminds the medical community that lasers are not only used for therapeutic purposes but can also induce specific responses through laser therapy. Notably, while laser therapy is frequently employed in treating cutaneous sarcoidosis, its role in inducing sarcoidosis warrants further investigation.

Occupational exposures and sarcoidosis: a rapid review of the evidence

BACKGROUND

Sarcoidosis is a rare, multisystem, inflammatory condition associated with the formation of granulomas. Diagnosis can be challenging because of non-specific symptoms complicating epidemiological investigations of its aetiology. Despite research efforts, a review of the current state of the evidence is needed.

AIMS

To assess the evidence for an association between occupational exposures and the development of sarcoidosis. To determine if workers in any occupation are at a greater risk of developing sarcoidosis.

METHODS

This rapid review follows the methodology suggested by the World Health Organization. Two electronic databases were systematically searched until April 2022. The methodological quality of the studies was critically appraised, and a best-evidence approach was used to synthesize the results.

RESULTS

Titles and abstracts of 2916 articles were screened, with 67 full-text articles reviewed for eligibility. Among the 13 studies eligible for this review, none were of high quality (i.e. low risk of bias). Six studies exploring the association between sarcoidosis and a range of occupations and exposures, and one previous systematic review were of low quality reporting inconsistent findings. Six studies examined the risk of sarcoidosis associated with occupational silica exposure, two of which were of acceptable quality. Overall, the study methodologies and results were inadequate to support causal relationships.

CONCLUSIONS

There is limited evidence of acceptable methodological quality to assess the risk of sarcoidosis associated with occupational exposures. There is a growing body of research examining occupational exposure to silica and sarcoidosis. Additional high-quality confirmatory research is needed.

History and Familial Aggregation of Immune-Mediated Diseases in Sarcoidosis: A Register-Based Case-Control-Family Study

BACKGROUND

An autoimmune component in the cause of sarcoidosis has long been debated, but population-based data on the clustering of immune-mediated diseases (IMDs) and sarcoidosis in individuals and families suggestive of shared cause are limited.

RESEARCH QUESTION

Do patients with a history of IMDs have a higher risk of sarcoidosis and do IMDs cluster in families with sarcoidosis?

STUDY DESIGN AND METHODS

We conducted a case-control-family study (2001-2020). Patients with sarcoidosis (N = 14,146) were identified in the Swedish National Patient Register using a previously validated definition (≥ 2 International Classification of Diseases [ICD]-coded inpatient or outpatient visits). At diagnosis, patients were matched to up to 10 control participants from the general population (N = 118,478) for birth year, sex, and residential location. Patients, control participants, and their first-degree relatives (FDRs; Multi-Generation Register) were ascertained for IMDs by means of ICD codes in the Patient Register (1968-2020). Conditional logistic regression was used to estimate ORs and 95% CIs of sarcoidosis associated with a history of IMDs in patients and control participants and in FDRs.

RESULTS

Patients with sarcoidosis exhibited a higher prevalence of IMDs compared with control participants (7.7% vs 4.7%), especially connective tissue diseases, cytopenia, and celiac disease. Familial aggregation was observed across IMDs; the strongest association was with celiac disease (OR, 2.09; 95% CI, 1.22-3.58), followed by cytopenia (OR, 1.88; 95% CI, 0.97-3.65), thyroiditis (OR, 1.72; 95% CI, 1.14-2.60), skin psoriasis (OR, 1.70; 95% CI, 1.34-2.15), inflammatory bowel disease (OR, 1.53; 95% CI, 1.14-2.03), immune-mediated arthritis (OR, 1.49; 95% CI, 1.20-1.85), and connective tissue disease (OR, 1.39; 95% CI, 1.00-1.93).

INTERPRETATION

This study showed that IMDs confer a higher risk of sarcoidosis and they aggregate in families with sarcoidosis, signaling a shared cause between IMDs and sarcoidosis. Our findings warrant further evaluation of shared genetic mechanisms.

Infectious and non-infectious precipitants of sarcoidosis

Sarcoidosis is a chronic inflammatory disease that can affect any organ in the body. Its exact cause remains unknown, but it is believed to result from a combination of genetic and environmental factors. Some potential causes of sarcoidosis include genetics, environmental triggers, immune system dysfunction, the gut microbiome, sex, and race/ethnicity. Genetic mutations are associated with protection against disease progression or an increased susceptibility to more severe disease, while exposure to certain chemicals, bacteria, viruses, or allergens can trigger the formation of immune cell congregations (granulomas) in different organs. Dysfunction of the immune system, including autoimmune reactions, may also contribute. The gut microbiome and factors such as being female or having African American, Scandinavian, Irish, or Puerto Rican heritage are additional contributors to disease outcome. Recent research has suggested that certain drugs, such as anti-Programmed Death-1 (PD-1) and antibiotics such as tuberculosis (TB) drugs, may raise the risk of developing sarcoidosis. Hormone levels, particularly higher levels of estrogen and progesterone in women, have also been linked to an increased likelihood of sarcoidosis. The diagnosis of sarcoidosis involves a comprehensive assessment that includes medical history, physical examination, laboratory tests, and imaging studies. While there is no cure for sarcoidosis, the symptoms can often be effectively managed through various treatment options. Treatment may involve the use of medications, surgical interventions, or lifestyle changes. These disparate factors suggests that sarcoidosis has multiple positive and negative exacerbants on disease severity, some of which can be ameliorated and others which cannot.

Advance in pathogenesis of sarcoidosis: Triggers and progression

Sarcoidosis, a multisystemic immune disease, significantly impacts patients' quality of life. The complexity and diversity of its pathogenesis, coupled with limited comprehensive research, had hampered both diagnosis and treatment, resulting in an unsatisfactory prognosis for many patients. In recent years, the research had made surprising progress in the triggers of sarcoidosis (genetic inheritance, infection and environmental factors) and the abnormal regulations on immunity during the formation of granuloma. This review consolidated the latest findings on sarcoidosis research, providing a systematic exploration of advanced studies on triggers, immune-related regulatory mechanisms, and clinical applications. By synthesizing previous discoveries, we aimed to offer valuable insights for future research directions and the development of clinical diagnosis and treatment strategies.

Occupational interstitial lung diseases

Millions of workers are exposed to substances known to cause occupational interstitial lung diseases (ILDs), particularly in developing countries. However, the burden of the disease is likely to be underestimated due to under-recognition, under-reporting or both. The diagnosis of occupational ILD requires a high level of suspicion and a thorough occupational history, as occupational and non-occupational ILDs may be clinically, functionally and radiologically indistinguishable, leading to delayed diagnosis and inappropriate management. A potential occupational aetiology should always be considered in the differential diagnosis of ILD, as removal from the workplace exposure, with or without treatment, is a key therapeutic intervention and may lead to significant improvement. In this article, we provide an overview of the 'traditional' inorganic dust-related ILDs but also address idiopathic pulmonary fibrosis and the immunologically mediated chronic beryllium disease, sarcoidosis and hypersensitivity pneumonitis, with emphasis on the importance of surveillance and prevention for reducing the burden of these conditions. To this end, health-care professionals should be specifically trained about the importance of occupational exposures as a potential cause of ILD.

Pulmonary sarcoidosis: A comprehensive review: Past to present

Sarcoidosis is a sterile non-necrotizing granulomatous disease without known causes that can involve multiple organs with a predilection for the lung and thoracic lymph nodes. Worldwide it is estimated to affect 2-160/100,000 people and has a mortality rate over 5 years of approximately 7%. For sarcoidosis patients, the cause of death is due to sarcoid in 60% of the cases, of which up to 80% are from advanced cardiopulmonary failure (pulmonary hypertension and respiratory microbial infections) in all races except in Japan were greater than 70% of the sarcoidosis deaths are due to cardiac sarcoidosis. Scadding stages for pulmonary sarcoidosis associates with clinical outcomes. Stages I and II have radiographic remission in approximately 30%-80% of cases. Stage III only has a 10%-40% chance of resolution, while stage IV has no change of resolution. Up to 40% of pulmonary sarcoidosis patients progress to stage IV disease with lung parenchyma fibroplasia, bronchiectasis with hilar retraction and fibrocystic disease. These patients are at highest risk for the development of precapillary pulmonary hypertension, which may occur in up to 70% of these patients. Sarcoid patients with pre-capillary pulmonary hypertension can respond to targeted pulmonary arterial hypertension medications. Stage IV fibrocytic sarcoidosis with significant pulmonary physiologic impairment, >20% fibrosis on HRCT or pre-capillary pulmonary hypertension have the highest risk of mortality, which can be >40% at 5-years. First line treatment for patients who are symptomatic (cough and dyspnea) with parenchymal infiltrates and abnormal pulmonary function testing (PFT) is oral glucocorticoids, such as prednisone with a typical starting dose of 20-40 mg daily for 2 weeks to 2 months. Prednisone can be tapered over 6-18 months if symptoms, spirometry, PFTs, and radiographs improve. Prolonged prednisone may be required to stabilize disease. Patients requiring prolonged prednisone ≥10 mg/day or those with adverse effects due to glucocorticoids may be prescribed second and third line treatements. Second and third line treatments include immunosuppressive agents (e.g., methotrexate and azathioprine) and anti-tumor necrosis factor (TNF) medication; respectively. Effective treatments for advanced fibrocystic pulmonary disease are being explored. Despite different treatments, relapse rates range from 13% to 75% depending on the stage of sarcoid, number of organs involved, socioeconomic status, and geography. CONCLUSION: The mortality rate for sarcoidosis over a 5 year follow up is approximately 7%. Unfortunately, 10%-40% of patients with sarcoidosis develop progressive pulmonary disease, and >60% of deaths resulting from sarcoidosis are due to advance cardiopulmonary disease. Oral glucocorticoids are the first line treatment, while methotrexate and azathioprine are considered second and anti-TNF agents are third line treatments that are used solely or as glucocorticoid sparing agents for symptomatic extrapulmonary or pulmonary sarcoidosis with infiltrates on chest radiographs and abnormal PFT. Relapse rates have ranged from 13% to 75% depending on the population studied.

Update on cardiac sarcoidosis

Cardiac sarcoidosis is an inflammatory myocardial disease of unknown etiology. It is characterized by the deposition of non-caseating granulomas that may involve any part of the heart. Cardiac sarcoidosis is often under-diagnosed or recognized partly due to the heterogeneous clinical presentation of the disease. The three most frequent clinical manifestations of cardiac sarcoidosis are atrioventricular block, ventricular arrhythmias, and heart failure. A definitive diagnosis of cardiac sarcoidosis can be made with histology findings from an endomyocardial biopsy. However, the diagnosis in the majority of cases is based on findings from the clinical presentation and advanced imaging due to the low sensitivity of endomyocardial biopsy. The Heart Rhythm Society (HRS) 2014 expert consensus statement and the Japanese Ministry of Health and Welfare criteria are the two most commonly used diagnostic criteria sets. This review article summarizes the available evidence on cardiac sarcoidosis, focusing on the diagnostic criteria and stepwise approach to its management.

Pulmonary Sarcoidosis: Experimental Models and Perspectives of Molecular Diagnostics Using Quantum Dots

Sarcoidosis is a complex inflammatory multisystem disease of unknown etiology that is characterised by epithelioid cell granulomatous lesions affecting various organs, mainly the lungs. In general, sarcoidosis is asymptomatic, but some cases result in severe complications and organ failure. So far, no accurate and validated modelling for clinical and pathohistological manifestations of sarcoidosis is suggested. Moreover, knowledge about disease-specific diagnostic markers for sarcoidosis is scarce. For instance, pulmonary granulomatosis is associated with the upregulated production of proinflammatory molecules: TNF-α, IL-6, CXCL1, CCL2, CCL18, CD163, serum angiotensin-converting enzyme (sACE), lysozyme, neopterin, and serum amyloid A (SAA). Quantum dots (QDs) are widely applied for molecular diagnostics of various diseases. QDs are semiconductor nanoparticles of a few nanometres in size, made from ZnS, CdS, ZnSe, etc., with unique physical and chemical properties that are useful for the labelling and detection in biological experiments. QDs can conjugate with various antibodies or oligonucleotides, allowing for high-sensitivity detection of various targets in organs and cells. Our review describes existing experimental models for sarcoidosis (in vitro, in vivo, and in silico), their advantages and restrictions, as well as the physical properties of quantum dots and their potential applications in the molecular diagnostics of sarcoidosis. The most promising experimental models include mice with TSC2 deletion and an in silico multiscale computational model of sarcoidosis (SarcoidSim), developed using transcriptomics and flow cytometry of human sarcoid biopsies. Both models are most efficient to test different candidate drugs for sarcoidosis.

Epidemiology of Sarcoidosis in U.S. Veterans from 2003 to 2019

Rationale: United States veterans represent an important population to study sarcoidosis. Their unique history of environmental exposures, wide geographic distribution, and long-term enrollment in a single integrated healthcare system provides an unparalleled opportunity to understand the incidence, prevalence, and risk factors for sarcoidosis. Objectives: To determine the epidemiology, patient characteristics, geographic distribution, and associated risk factors of sarcoidosis among U.S. veterans. Methods: We used data from the Veterans Health Administration (VHA) electronic health record system between 2003 and 2019 to evaluate the annual incidence, prevalence, and geographic distribution of sarcoidosis (defined using the International Classification of Diseases codes). We used multivariate logistic regression to examine patient characteristics associated with sarcoidosis incidence. Results: Among more than 13 million veterans who received care through or paid for by the VHA, 23,747 (0.20%) incident diagnoses of sarcoidosis were identified. Compared with selected VHA control subjects using propensity score matching, veterans with sarcoidosis were more likely to be female (13.5% vs. 9.0%), of Black race (52.2% vs. 17.0%), and ever-tobacco users (74.2% vs. 64.5%). There was an increase in the annual incidence of sarcoidosis between 2004 and 2019 (from 38 to 52 cases/100,000 person-years) and the annual prevalence between 2003 and 2019 (from 79 to 141 cases/100,000 persons). In a multivariate logistic regression model, Black race (odds ratio [OR], 4.49; 95% confidence interval [CI], 4.33-4.65), female sex (OR, 1.64; 95% CI, 1.56-1.73), living in the Northeast compared with the western region (OR, 1.57; 95% CI, 1.48-1.67), history of tobacco use (OR, 1.36; 95% CI, 1.31-1.41), and serving in the Army, Air Force, or multiple branches compared with the Navy (OR, 1.08; 95% CI, 1.03-1.13; OR, 1.10; 95% CI, 1.04-1.17; OR, 1.27; 95% CI, 1.16-1.39, respectively) were significantly associated with incident sarcoidosis (P < 0.0001). Conclusions: The incidence and prevalence of sarcoidosis are higher among veterans than in the general population. Alongside traditionally recognized risk factors such as Black race and female sex, we found that a history of tobacco use within the Veterans Affairs population and serving in the Army, Air Force, or multiple service branches were associated with increased sarcoidosis risk.

Occupational Interstitial Lung Diseases

Occupational exposures are directly causal or partially contributory to the development of interstitial lung diseases. A detailed occupational history, relevant high-resolution computed tomography findings, and where relevant additional histopathology, are required to make a diagnosis. Treatment options are limited, and further exposure avoidance is likely to reduce disease progression.

Pulmonary sarcoid-like granulomatosis induced by aluminum dust: A case report and literature review

Case report

We present a case of a 48-year-old woman with 27 months of exposure to aluminum dust and silica owing to polishing processing. The patient was admitted to our hospital with intermittent cough and expectoration. Chest high-resolution computed tomography showed diffuse ill-defined centrilobular nodules and patchy ground-glass opacities in bilateral lungs. A video-assisted thoracoscopic surgery biopsy demonstrated multiple isolated and confluent granulomas in an otherwise normal parenchyma without malignancy or signs of infection. Elemental analysis was performed on the grinding wheel powder in the workplace using an X-ray fluorescence spectrometric analyzer, showing 72.7% of Al₂O₃ and 22.8% of SiO₂ as raw materials. She was diagnosed with aluminum-associated sarcoid-like granulomatous lung disease, rather than sarcoidosis, according to occupational exposure by a multidisciplinary panel.

Conclusion

Occupational aluminum dust exposure may induce pulmonary sarcoid-like granulomatosis recognized by a multidisciplinary diagnostic panel.

An expert overview of pulmonary fibrosis in sarcoidosis

INTRODUCTION

Advanced pulmonary sarcoidosis refers to phenotypes of pulmonary sarcoidosis that often lead to significant loss of lung function, respiratory failure, or death. Around 20% of patients with sarcoidosis may progress to this state which is mainly driven by advanced pulmonary fibrosis. Advanced fibrosis often presents with associated complications of sarcoidosis including infections, bronchiectasis, and pulmonary hypertension.

AREAS COVERED

This article will focus on the pathogenesis, natural history of disease, diagnosis, and potential treatment options of pulmonary fibrosis in sarcoidosis. In the expert opinion section, we will discuss the prognosis and management of patients with significant disease.

EXPERT OPINION

While some patients with pulmonary sarcoidosis remain stable or improve with anti-inflammatory therapies, others develop pulmonary fibrosis and further complications. Although advanced pulmonary fibrosis is the leading cause of death in sarcoidosis, there are no evidence-based guidelines for the management of fibrotic sarcoidosis. Current recommendations are based on expert consensus and often include multidisciplinary discussions with experts in sarcoidosis, pulmonary hypertension, and lung transplantation to facilitate care for such complex patients. Current works evaluating treatments include the use of antifibrotic therapies for treatment in advanced pulmonary sarcoidosis.

Genetics of neurosarcoidosis

Sarcoidosis is a systemic, inflammatory, granulomatous disease characterized by great variability in organ involvement, clinical course, and severity. While pulmonary manifestations are almost universal, the central and peripheral nervous systems can also be affected. Neurosarcoidosis occurs in ∼5-15% of cases and is among the manifestations with the highest morbidity and mortality. It is known that sarcoidosis has genetic underpinnings and while multiple studies aimed at identifying associations to sarcoidosis susceptibility and prognosis, very few studies have focused on neurosarcoidosis. This review summarizes the genetic studies to date, compares and contrasts those findings with other genetic effects in sarcoidosis, and offers ideas for moving the field forward.

The Evolving Landscape of Cutaneous Sarcoidosis: Pathogenic Insight, Clinical Challenges, and New Frontiers in Therapy

Sarcoidosis is a multisystem disorder of unknown etiology characterized by accumulation of granulomas in affected tissue. Cutaneous manifestations are among the most common extrapulmonary manifestations in sarcoidosis and can lead to disfiguring disease requiring chronic therapy. In many patients, skin disease may be the first recognized manifestation of sarcoidosis, necessitating a thorough evaluation for systemic involvement. Although the precise etiology of sarcoidosis and the pathogenic mechanisms leading to granuloma formation, persistence, or resolution remain unclear, recent research has led to significant advances in our understanding of this disease. This article reviews recent advances in epidemiology, sarcoidosis clinical assessment with a focus on the dermatologist's role, disease pathogenesis, and new therapies in use and under investigation for cutaneous and systemic sarcoidosis.

Sarcoidosis in Northern Ontario hard-rock miners: A case series

Sarcoidosis is a rare multisystem granulomatous disease traditionally considered to be of unknown etiology. The notion that sarcoidosis has no known cause is called into question with the increasing number of case reports and epidemiologic studies showing associations between occupational exposures and disease published in the past 10-20 years. Occupational exposures for which associations are strongest and most consistent are silica and other inorganic dusts, World Trade Center (WTC) dust, and metals. Occupations identified as at-risk for sarcoidosis include construction workers; iron-foundry and diatomaceous earth workers; WTC emergency responders; and metal workers. We report here 12 cases of sarcoidosis in a cohort of hard-rock miners in Northern Ontario, Canada. To our knowledge sarcoidosis has not been reported previously in hard-rock miners. The cases are all male and Caucasian, with average age 74 years. At the time of diagnosis, two were never smokers; six, former smokers; and four, current smokers. Five have extrapulmonary sarcoidosis: two cardiac and three endocrine (hypercalciuria). Using occupational histories and air sampling data from the gold, uranium, and base-metal mines in which they worked, we examined exposure of each case to respirable crystalline silica (RCS). The annual mean RCS exposure for the 12 cases was 0.14 mg/m³ (range: 0.06-1.3 mg/m³ ); and the mean cumulative RCS exposure was 1.93 mg/m³  years (range: 0.64-4.03 mg/m³  years). We also considered their exposure to McIntyre Powder, an aluminum powder used for silicosis prophylaxis.

Assessment of Experimental Techniques That Facilitate Human Granuloma Formation in an In Vitro System: A Systematic Review

The process of granuloma formation is complex, and due to species differences, the validity of animal studies is somewhat questioned. Moreover, the large number of animals needed to observe the different stages of development also raises ethical questions. Therefore, researchers have explored the use of human peripheral blood mononuclear cells (PBMCs), a heterogeneous population of immune cells, in an in vitro model. This review included in vitro studies that focused on exposing PBMCs—from healthy, sensitized, or diseased individuals—to antigens derived from infectious agents—such as mycobacteria or Schistosoma spp.—or inorganic antigens—such as beryllium. The reviewed studies mainly explored how human in vitro granuloma models can contribute towards understanding the pathogenesis of granulomatous diseases, especially during the early stages of granuloma formation. The feasibility of granuloma modelling was thus largely assessed via experimental techniques including (1) granuloma scoring indices (GI), (2) cell surface markers and (3) cytokine secretion profiling. While granuloma scoring showed some similarities between studies, a large variability of culture conditions and endpoints measured have been identified. The lack of any standardization currently impedes the success of a human in vitro granuloma model.

Diagnosis and Treatment of Pulmonary Sarcoidosis: A Review

IMPORTANCE

Sarcoidosis is an inflammatory granulomatous disease of unknown cause that affects an estimated 2 to 160 people per 100 000 worldwide and can involve virtually any organ. Approximately 10% to 30% of patients with sarcoidosis develop progressive pulmonary disease.

OBSERVATION

Among patients with pulmonary sarcoidosis, the rate of spontaneous remission without serious sequelae ranges from 10% to 82%. However, lung disease progression occurs in more than 10% of patients and can result in fibrocystic architectural distortion of the lung, which is associated with a mortality rate of 12% to 18% within 5 years. Overall, the mortality rate for sarcoidosis is approximately 7% within a 5-year follow-up period. Worldwide, more than 60% of deaths from sarcoidosis are due to pulmonary involvement; however, more than 70% of deaths from sarcoidosis are due to cardiac involvement in Japan. Up to 70% of patients with advanced pulmonary sarcoidosis develop precapillary pulmonary hypertension, which is associated with a 5-year mortality rate of approximately 40%. Patients with sarcoidosis and precapillary pulmonary hypertension should be treated with therapies such as phosphodiesterase inhibitors and prostacyclin analogues. Although optimal doses of oral glucocorticoids for pulmonary sarcoidosis are unknown, oral prednisone typically starting at a dose of 20 mg/d to 40 mg/d for 2 to 6 weeks is recommended for patients who are symptomatic (cough, dyspnea, and chest pain) and have parenchymal infiltrates and abnormal pulmonary function test results. Oral glucocorticoids can be tapered over 6 to 18 months if symptoms, pulmonary function test results, and radiographs improve. Prolonged use of oral glucocorticoids may be required to control symptoms and stabilize disease. Patients without adequate improvement while receiving a dose of prednisone of 10 mg/d or greater or those with adverse effects due to glucocorticoids may be prescribed immunosuppressive agents, such as methotrexate, azathioprine, or an anti-tumor necrosis factor medication, either alone or with glucocorticoids combined with appropriate microbial prophylaxis for Pneumocystis jiroveci and herpes zoster. Effective treatments are not available for advanced fibrocystic pulmonary disease.

CONCLUSIONS AND RELEVANCE

Sarcoidosis has a mortality rate of approximately 7% within a 5-year follow-up period. More than 10% of patients with pulmonary sarcoidosis develop progressive disease and more than 60% of deaths are due to advanced pulmonary sarcoidosis. Oral glucocorticoids with or without another immunosuppressive agent are the first-line therapy for symptomatic patients with abnormal pulmonary function test results and lung infiltrates. Patients with sarcoidosis and precapillary pulmonary hypertension should be treated with therapies such as phosphodiesterase inhibitors and prostacyclin analogues.

The EXIMIOUS project—Mapping exposure-induced immune effects: connecting the exposome and the immunome

Immune-mediated, noncommunicable diseases—such as autoimmune and inflammatory diseases—are chronic disorders, in which the interaction between environmental exposures and the immune system plays an important role. The prevalence and societal costs of these diseases are rising in the European Union. The EXIMIOUS consortium—gathering experts in immunology, toxicology, occupational health, clinical medicine, exposure science, epidemiology, bioinformatics, and sensor development—will study eleven European study populations, covering the entire lifespan, including prenatal life. Innovative ways of characterizing and quantifying the exposome will be combined with high-dimensional immunophenotyping and -profiling platforms to map the immune effects (immunome) induced by the exposome. We will use two main approaches that “meet in the middle”—one starting from the exposome, the other starting from health effects. Novel bioinformatics tools, based on systems immunology and machine learning, will be used to integrate and analyze these large datasets to identify immune fingerprints that reflect a person’s lifetime exposome or that are early predictors of disease. This will allow researchers, policymakers, and clinicians to grasp the impact of the exposome on the immune system at the level of individuals and populations.

Sarcoid-like Granulomatous Lung Disease with Subacute Progression in Silicosis

A 67-year-old man was admitted to our hospital with cough and fatigue. He had had long-term exposure to silica due to cement processing. Chest computed tomography showed bilateral centrilobular nodules, and hilar and mediastinal lymphadenopathy with calcification, suggesting chronic silicosis. Within a few months, these nodules enlarged, and bilateral patchy consolidations appeared. A lung biopsy revealed sarcoid-like granulomas with birefringent particles under polarized light without malignancy or infection. He was diagnosed with silicosis-associated sarcoid-like granulomatous lung disease, rather than sarcoidosis, according to the clinicopathological findings. His pulmonary manifestations improved after the discontinuation of silica exposure and combination therapy of corticosteroid and azathioprine.

Free-breathing MR elastography of the lungs: An in vivo study

PURPOSE

Lung stiffness alters with many diseases; therefore, several MR elastography (MRE) studies were performed earlier to investigate the stiffness of the right lung during breathhold at residual volume and total lung capacity. The aims of this study were 1) to estimate shear stiffness of the lungs using MRE under free breathing and demonstrate the measurements' repeatability and reproducibility, and 2) to compare lung stiffness under free breathing to breathhold and as a function of age and gender.

METHODS

Twenty-five healthy volunteers were scanned on a 1.5 Tesla MRI scanner. Spin-echo dual-density spiral and a spin-echo EPI MRE sequences were used to measure shear stiffness of the lungs during free breathing and breathhold at midpoint of tidal volume, respectively. Concordance correlation coefficient and Bland-Altman analyses were performed to determine the repeatability and reproducibility of the spin-echo dual-density spiral-derived shear stiffness. Repeated measures analyses of variances were used to investigate differences in shear stiffness between spin-echo dual-density spiral and spin-echo EPI, right and left lungs, males and females, and different age groups.

RESULTS

Free-breathing MRE sequence was highly repeatable and reproducible (concordance correlation coefficient > 0.86 for both lungs). Lung stiffness was significantly lower in breathhold than in free breathing (P < .001), which can be attributed to potential stress relaxation of lung parenchyma or breathhold inconsistencies. However, there was no significant difference between different age groups (P = .08). The left lung showed slightly higher stiffness values than the right lung (P = .14). There is no significant difference in lung stiffness between genders.

CONCLUSION

This study demonstrated the feasibility of free-breathing lung MRE with excellent repeatability and reproducibility. Stiffness changes with age and during the respiratory cycle. However, gender does not influence lungs stiffness.

Sarcoidosis - A review article

Sarcoidosis is a granulomatous disorder of multiple organs, with lungs and lymphatic systems being the most frequently affected sites of the body. It was first reported in 1877 and has continued to engross both clinicians and scientists since that time. Because sarcoidosis being a diagnosis of exclusion, it demands the physician to rule out all the possible diagnosis. Most of the patients remain asymptomatic and this makes the disease remain unnoticed for a prolonged period. Later after years, the disease could be diagnosed after witnessing the patient being symptomatic or suffering from organ failures. It could affect middle aged people of any sexes, often its clinical features correlate with tuberculosis. On immunological and histopathological examination, it reveals noncaseating granuloma in simple terms. Glucocorticoids remain the standard drug now and then. Further research has to be done to know the exact pathogenesis, early detection and betterment in treatment plan of sarcoidosis. The current review article gives a brief knowledge about etiopathogenesis, Clinical features, upgraded diagnostic methods such as biomarkers detection and the organized treatment plan to treat sarcoidosis.

Myeloid ABCG1 Deficiency Enhances Apoptosis and Initiates Efferocytosis in Bronchoalveolar Lavage Cells of Murine Multi-Walled Carbon Nanotube-Induced Granuloma Model

The use of carbon nanotubes has increased in the past few decades. Carbon nanotubes are implicated in the pathogenesis of pulmonary sarcoidosis, a chronic granulomatous inflammatory condition. We developed a murine model of chronic granulomatous inflammation using multiwall carbon nanotubes (MWCNT) to investigate mechanisms of granuloma formation. Using this model, we demonstrated that myeloid deficiency of ATP-binding cassette (ABC) cholesterol transporter (ABCG1) promotes granuloma formation and fibrosis with MWCNT instillation; however, the mechanism remains unclear. Our previous studies showed that MWCNT induced apoptosis in bronchoalveolar lavage (BAL) cells of wild-type (C57BL/6) mice. Given that continual apoptosis causes persistent severe lung inflammation, we hypothesized that ABCG1 deficiency would increase MWCNT-induced apoptosis thereby promoting granulomatous inflammation and fibrosis. To test our hypothesis, we utilized myeloid-specific ABCG1 knockout (ABCG1 KO) mice. Our results demonstrate that MWCNT instillation enhances pulmonary fibrosis in ABCG1 KO mice compared to wild-type controls. Enhanced fibrosis is indicated by increased trichrome staining and transforming growth factor-beta (TGF-β) expression in lungs, together with an increased expression of TGF-β related signaling molecules, interleukin-13 (IL-13) and Smad-3. MWCNT induced more apoptosis in BAL cells of ABCG1 KO mice. Initiation of apoptosis is most likely mediated by the extrinsic pathway since caspase 8 activity and Fas expression are significantly higher in MWCNT instilled ABCG1 KO mice compared to the wild type. In addition, TUNEL staining shows that ABCG1 KO mice instilled with MWCNT have a higher percentage of TUNEL positive BAL cells and more efferocytosis than the WT control. Furthermore, BAL cells of ABCG1 KO mice instilled with MWCNT exhibit an increase in efferocytosis markers, milk fat globule-EGF factor 8 (MFG-E8) and integrin β3. Therefore, our observations suggest that ABCG1 deficiency promotes pulmonary fibrosis by MWCNT, and this effect may be due to an increase in apoptosis and efferocytosis in BAL cells.

Putative role of prosthetic dental implants in the development of cardiac sarcoidosis: A case-control study

Background:

Etiopathogenesis of cardiac sarcoidosis is poorly understood. The objective of this study is to examine a possible role of previous dental procedures on the development of cardiac sarcoidosis (CS).

Methods:

Clinical details of 73 patients with CS from the Granulomatous Myocarditis Registry were extracted. Data regarding clinical presentation, comorbidities, baseline electrocardiogram, echocardiogram, and ¹⁸fluorodeoxyglucose(FDG) PET-CT was extracted from the registry database. A comprehensive history of dental procedures for all patients was recorded. The two control groups comprised of 79 patients with idiopathic ventricular tachycardia and/or complete heart block (with similar clinical presentation) and 145 healthy age and sex matched patients, respectively.

Results:

Dental evaluation revealed that patients with CS had undergone a previous prosthetic dental implant(PI) (OR 12.4, 95% CI 4.0-38.1, p<0.001) or root canal treatment (RCT) (OR 2.43, 95% CI 1.12-5.26, p=0.025) more often than the healthy controls. The patients with CS and previous dental procedures had higher¹⁸FDG uptake in the LV myocardium (SUV max 8.6±3.3vs.5.5 ±1.8 (mean±SD), p<0.001) and mediastinal lymph nodes (9.3±4.6vs.5.4±1.7 (mean±SD), p<0.001) as compared to patients who did not undergo a dental procedure. The subset of CS patients with a previous PI or RCT had higher uptake levels in the myocardium (max SUV 9.4±3.1vs.6.7±2.0, p=0.011, number of abnormal LV Segments 10.3±3.1vs.6.5±2.8(mean±SD), p=0.008) and mediastinal lymph nodes(max SUV 10.5±4.8vs. 7.2±1.8,p=0.002) compared to those who underwent crowning or extraction. In addition, CS was diagnosed after a shorter latency period (47.3±21.0vs.81.6±25.3 months (mean±SD), p<0.001) following PI and RCT compared to other dental procedures.

Conclusions:

We observed a significant association between PI and RCT and the occurrence of CS. This group of patients also appear to have a more severe form of the disease.

Exposure to inorganic particles in paediatric sarcoidosis: the PEDIASARC study

Inorganic antigens may contribute to paediatric sarcoidosis. Thirty-six patients matched with 36 healthy controls as well as a group of 21 sickle-cell disease (SCD) controls answered an environmental questionnaire. Patients' indirect exposure to inorganic particles, through coresidents' occupations, was higher than in healthy and SCD controls (median score: 2.5 (0.5-7) vs 0.5 (0-2), p=0.003 and 1 (0-2), p=0.012, respectively), especially for construction, exposures to metal dust, talc, abrasive reagents and scouring products. Wood or fossil energies heating were also linked to paediatric sarcoidosis. This study supports a link between mineral environmental exposure due to adult coresident occupations and paediatric sarcoidosis.

Cardiac Sarcoidosis: A Clinical Overview

Cardiac sarcoidosis (CS) with clinical manifestation occurs in about 5-8% of patients with sarcoidosis. CS may be clinically suspected by the presence of ventricular arrhythmia, conduction abnormalities, and heart failure (HF). However, 20%-25% of patients may present with silent CS, having asymptomatic cardiac involvement. The diagnosis of CS is based on findings from nuclear studies, cardiac magnetic resonance, and extra-cardiac tissue biopsy. Due to the inflammatory nature of the disease, immunosuppressive medications are a cornerstone of therapy. The treatment also includes recommended HF medical therapies. Since CS patients are at risk of sudden cardiac death resulting from progression of cardiac dysfunction or the presence of scar originating from fatal arrhythmias, implantable cardioverter-defibrillators should be considered, with special indication beyond accepted recommendations in HF. In CS, the extent of left ventricular dysfunction is the most important mortality predictor. Heart transplant or mechanical circulatory support may represent life saving strategies in selective CS patients.

Identification of microbial agents in tissue specimens of ocular and periocular sarcoidosis using a metagenomics approach

Background: Metagenomic sequencing has the potential to identify a wide range of pathogens in human tissue samples. Sarcoidosis is a complex disorder whose etiology remains unknown and for which a variety of infectious causes have been hypothesized. We sought to conduct metagenomic sequencing on cases of ocular and periocular sarcoidosis, none of them with previously identified infectious causes. Methods: Archival tissue specimens of 16 subjects with biopsies of ocular and periocular tissues that were positive for non-caseating granulomas were used as cases. Four archival tissue specimens that did not demonstrate non-caseating granulomas were also included as controls. Genomic DNA was extracted from tissue sections. DNA libraries were generated from the extracted genomic DNA and the libraries underwent next-generation sequencing. Results: We generated between 4.8 and 20.7 million reads for each of the 16 cases plus four control samples. For eight of the cases, we identified microbial pathogens that were present well above the background, with one potential pathogen identified for seven of the cases and two possible pathogens for one of the cases. Five of the eight cases were associated with bacteria ( Campylobacter concisus, Neisseria elongata, Streptococcus salivarius, Pseudopropionibacterium propionicum, and Paracoccus yeei), two cases with fungi ( Exophiala oligosperma, Lomentospora prolificans and Aspergillus versicolor) and one case with a virus (Mupapillomavirus 1). Interestingly, four of the five bacterial species are also part of the human oral microbiome. Conclusions: Using a metagenomic sequencing we identified possible infectious causes in half of the ocular and periocular sarcoidosis cases analyzed. Our findings support the proposition that sarcoidosis could be an etiologically heterogenous disease. Because these are previously banked samples, direct follow-up in the respective patients is impossible, but these results suggest that sequencing may be a valuable tool in better understanding the etiopathogenesis of sarcoidosis and in diagnosing and treating this disease.

Associations between occupational and environmental exposures and organ involvement in sarcoidosis: a retrospective case-case analysis

BACKGROUND

Sarcoidosis most commonly affects lungs and intrathoracic lymph nodes, but any other organ can be involved. In epidemiological studies, many occupational and environmental exposures have been linked to sarcoidosis but their relationship with the disease phenotype has barely been studied.

OBJECTIVE

To investigate how occupational and environmental exposures prior to diagnosis relate to organ involvement in patients with sarcoidosis METHODS: We retrospectively studied patients seen at a sarcoidosis clinic between 2017 and 2020. Patients were included if they had a clinical presentation consistent with sarcoidosis and histologically confirmed epithelioid granulomas or had Löfgren syndrome. In a case-case analysis using multivariable logistic regression we calculated odds ratios (OR) of prespecified exposure categories (based on expert ascertainment) for cases with a given organ involvement versus cases without this organ involvement.

RESULTS

We included 238 sarcoidosis patients. Sarcoidosis limited to pulmonary involvement was associated with exposure to inorganic dust prior to diagnosis (OR 2.11; 95% confidence interval [CI] 1.11-4.17). Patients with liver involvement had higher odds of contact with livestock (OR 3.68; 95% CI 0.91-12.7) or having jobs with close human contact (OR 4.33; 95% CI 1.57-11.3) than patients without liver involvement. Similar associations were found for splenic involvement (livestock: OR 4.94, 95% CI 1.46-16.1; close human contact: OR 3.78; 95% CI 1.47-9.46). Cardiac sarcoidosis was associated with exposure to reactive chemicals (OR 5.08; 95% CI 1.28-19.2) or livestock (OR 9.86; 95% CI 1.95-49.0). Active smokers had more ocular sarcoidosis (OR 3.26; 95% CI 1.33-7.79).

CONCLUSIONS

Our study indicates that, in sarcoidosis patients, different exposures might be related to different organ involvements-hereby providing support for the hypothesis that sarcoidosis has more than one cause, each of which may promote a different disease phenotype.

Sarcoidosis: An Occupational Disease?

Sarcoidosis is an important member of the family of granulomatous lung diseases. Since its recognition in the late 19th century, sarcoidosis has been thought of as a disease of unknown cause. Over the past 20 years, this paradigm has been shifting, more rapidly in the past 10 years. Epidemiologic studies, bolstered by case reports, have provided evidence of causal associations between occupational exposure to specific agents and sarcoidosis. Pathogenesis has been more clearly defined, including the role of gene-exposure interactions. The use of in vitro lymphocyte proliferation testing to detect sensitization to inorganic antigens is being examined in patients with sarcoidosis. These antigens include silica and certain metals. Results of studies to date show differences in immunoreactivity of occupationally exposed sarcoidosis cases compared with control cases, suggesting that lymphocyte proliferation testing may prove useful in diagnosing work-related disease. This review discusses recently published findings regarding associations between occupational exposure to silica and silicates, World Trade Center dust, and metals and risk for sarcoidosis, as well as advances in the development of diagnostic tools. Not all cases of sarcoidosis have an identified cause, but some do. Where the cause is occupational, its recognition is critical to enable effective treatment through removal of the affected worker from exposure and to inform intervention aimed at primary prevention.

Silicosis: An Update and Guide for Clinicians

This overview provides an update on silicosis epidemiology with review of exposures and emerging trends in acute and accelerated silicosis in the twenty-first century. The silicosis epidemics in mining, denim sandblasting, and engineering stone industries are highlighted. Clinical presentations of silicosis and silica-related conditions such as autoimmune, kidney, and mycobacterial disease, as well as lung cancer, are discussed. Important aspects of the new OSHA 2017 Silica Standard are presented. This review also includes practical guidance for clinicians to address questions that may arise when evaluating silica-exposed patients and to the public health responses needed following a diagnosis of silica-related disease.

Novel three-dimensional biochip pulmonary sarcoidosis model

Sarcoidosis is a multi-system disorder of granulomatous inflammation which most commonly affects the lungs. Its etiology and pathogenesis are not well defined in part due to the lack of reliable modeling. Here, we present the development of an in vitro three-dimensional lung-on-chip biochip designed to mimic granuloma formation. A lung on chip fluidic macrodevice was developed and added to our previously developed a lung-on-membrane model (LOMM). Granulomas were cultured from blood samples of patients with sarcoidosis and then inserted in the air-lung-interface of the microchip to create a three-dimensional biochip pulmonary sarcoidosis model (3D BSGM). Cytokines were measured after 48 hours. ELISA testing was performed to measure cytokine response difference between LOMM with 3D BSGM. There were statistically significant differences in IL-1ß (P = 0.001953), IL-6 (P = 0.001953), GM-CSF (P = 0.001953), and INF-γ expressions (P = 0.09375) between two groups. The current model represents the first 3D biochip sarcoidosis model created by adding a microfluidics system to a dual-chambered lung on membrane model and introducing developed sarcoid-granuloma to its air-lung-interface.

Potential use of biomarkers for the clinical evaluation of sarcoidosis

Sarcoidosis is a systemic granulomatous disease of unknown etiology and pathogenesis with a heterogeneous clinical presentation. In the appropriate clinical and radiological context and with the exclusion of other diagnoses, the disease is characterized by the pathological presence of non-caseating epithelioid cell granulomas. Sarcoidosis is postulated to be a multifactorial disease caused by chronic antigenic stimulation. The immunopathogenesis of sarcoidosis encompasses a complex interaction between the host, genetic factors and postulated environmental and infectious triggers, which result in granuloma development.The exact pathogenesis of the disease has yet to be elucidated, but some of the inflammatory pathways that play a key role in disease progression and outcomes are becoming apparent, and these may form the logical basis for selecting potential biomarkers.Biomarkers are biological molecules that are altered pathologically. To date, there exists no single reliable biomarker for the evaluation of sarcoidosis, either diagnostically or prognostically but new candidates are emerging. A diagnosis of sarcoidosis ideally requires a biopsy confirming non-caseating granulomas, but the likelihood of progression that requires intervention remains unpredictable. These challenging aspects could be potentially resolved by incorporating biomarkers into clinical practice for both diagnosis and monitoring disease activity.This review outlines the current knowledge on sarcoidosis with an emphasis on pulmonary sarcoidosis, and delineates the understanding surrounding the implication of biomarkers for the clinical evaluation of sarcoidosis.

Case Report: Pediatric Renal Sarcoidosis and Prognostic Factors in Reviewed Cases

Background: Pediatric sarcoidosis is a complex inflammatory disorder with multisystemic manifestations. Kidney involvement in children is rare, and prognostic factors are unknown. Case Report and Methods: We report the case of a 16-year-old girl with multiorgan sarcoidosis and renal involvement. The patient presented with tubulointerstitial nephritis, acute kidney injury (AKI), chest CT disseminated noduli, granulomatous iridocyclitis, giant-cell sialadenitis, and arthralgia. The kidney biopsy revealed non-granulomatous interstitial nephritis. Treatment consisted of initial high-dose methylprednisolone pulse followed by oral prednisolone and methotrexate. Full remission was achieved. In addition, we performed a literature review using PubMed and analyzed data on pediatric renal sarcoidosis cases. Results: We identified 36 cases of pediatric sarcoidosis with renal involvement on presentation and data on the end-of-follow-up glomerular filtration rate (GFR). The data from the literature review showed that renal involvement was slightly more prevalent in males (60%). AKI was present in most of the described patients (84%). Oral prednisolone was used in 35 of 36 cases; in more severe cases, other immunosuppressants were used. We newly identified renal concentration impairment and granulomatous interstitial nephritis as factors with a clear trend toward GFR loss at the end of follow-up, emphasizing the importance of kidney biopsy in symptomatic patients. In contrast, higher GFR at presentation and hypercalcemia were rather favorable factors. According to the identified predictive factors, our patient has a good prognosis and is in remission. Conclusion: The factors indicating a trend toward an unfavorable renal outcome in pediatric sarcoidosis are renal concentration impairment and granulomatous interstitial nephritis at presentation, while a higher GFR is beneficial.

Exploring Occupational, Recreational, and Environmental Associations in Patients With Clinically Manifest Cardiac Sarcoidosis

Background

Sarcoidosis is a condition of unknown etiology. A number of occupational, recreational, and environmental exposures have been associated with the development of extra-cardiac sarcoidosis. Patients with clinically manifest cardiac sarcoidosis (CS) have a distinct clinical phenotype. We sought to explore the exposures associated with clinically manifest CS.

Methods

Two groups of patients were recruited in a prospective registry: cases (patients with clinically manifest CS) and controls (patients without sarcoidosis and who had similar cardiac presentations to cases). A validated survey, previously used in other sarcoidosis phenotypes, was sent to all patients.

Results

A total of 113 patients met the inclusion criteria and were sent the survey, of whom 79 of 113 (69.9%) completed the survey. We found 3 environmental associations. First, we found a negative association of CS with smoking, with 8 of 43 (18.6%) CS patients being current or ex-smokers compared to 17 of 36 (47.2%) of the controls. Second, we found a positive association with mold exposure, with 21 of 43 (48.8%) CS patients having a prior history of mold exposure compared to 9 of 36 (25.0%) of the controls. After multivariable analysis, there remained significant associations between CS and smoking (odds ratio 0.14 [95% confidence interval 0.04-0.51], P = 0.002) and mold exposure (odds ratio 5.69 [95% confidence interval 1.68-19.25], P = 0.005). Finally, patients with CS and self-reported acne had a significantly longer duration of active acne (7.82 ± 3.97 years) than did control patients 2.67 ± 1.03 years (P = 0.006).

Conclusions

We found a negative association between smoking history and the diagnosis of CS. We also found a significant 5-fold increase in mold exposure and a positive association with duration of acne in patients with CS compared to controls.

Paediatric autoimmune and autoinflammatory conditions associated with uveitis

Childhood uveitis comprises a collection of heterogenous ocular phenotypes which are associated with a diverse range of childhood autoimmune and autoinflammatory disorders. Of these genetic and/or acquired disorders, juvenile idiopathic arthritis is the most common, affecting 30-80% of children with uveitis. Up to a third of children with uveitis have 'isolated' idiopathic disease and do not have an associated systemic disease which manifests in childhood. However, uveitis may be the presenting manifestation of disease; thus, the apparently well child who presents with uveitis may have isolated idiopathic disease, but they may have an evolving systemic disorder. The diagnosis of most of the associated disorders is reliant on clinical features rather than serological or genetic investigations, necessitating detailed medical history taking and systemic examination. Adequate control of inflammation is key to good visual outcomes, and multidisciplinary care is key to good broader health outcomes.

Systemic sarcoidosis revealed by venepunctures: a very rare but rewarding cutaneous manifestation

A 67-year-old man was referred to our department for the onset of cutaneous lesions following venepunctures. His recent medical history included brief flu-like syndrome, persistent cough, dyspnoea, dry mouth, blurred vision and weight loss. The extensive clinical, biological and radiological check-up showed signs consistent with systemic sarcoidosis: right uveitis, hypercalcemia, renal failure, inflammatory syndrome, elevated levels of ACE, alveolitis with elevated CD4+/CD8+ T cell ratio, hilar and mediastinal lymphadenopathy, bilateral pulmonary infiltrates, mild bronchial obstruction and lowered diffusing capacity of the lungs for carbon monoxide. Multiple biopsy samples (bronchus, accessory salivary glands and one of the skin lesions) eventually confirmed the diagnosis. Corticosteroids resulted in skin lesions resolution in a few days and overall clinical, biological and lung function improvement. The infiltration of scars by granulomatous tissue is well recognised in sarcoidosis but its onset in venepuncture sites is a very rare but easily recognisable condition, which can be helpful for quick diagnosis purpose.

Sarcoidosis: Causes, Diagnosis, Clinical Features, and Treatments

Sarcoidosis is a multisystem granulomatous disease with nonspecific clinical manifestations that commonly affects the pulmonary system and other organs including the eyes, skin, liver, spleen, and lymph nodes. Sarcoidosis usually presents with persistent dry cough, eye and skin manifestations, weight loss, fatigue, night sweats, and erythema nodosum. Sarcoidosis is not influenced by sex or age, although it is more common in adults (< 50 years) of African-American or Scandinavians decent. Diagnosis can be difficult because of nonspecific symptoms and can only be verified following histopathological examination. Various factors, including infection, genetic predisposition, and environmental factors, are involved in the pathology of sarcoidosis. Exposures to insecticides, herbicides, bioaerosols, and agricultural employment are also associated with an increased risk for sarcoidosis. Due to its unknown etiology, early diagnosis and detection are difficult; however, the advent of advanced technologies, such as endobronchial ultrasound-guided biopsy, high-resolution computed tomography, magnetic resonance imaging, and 18F-fluorodeoxyglucose positron emission tomography has improved our ability to reliably diagnose this condition and accurately forecast its prognosis. This review discusses the causes and clinical features of sarcoidosis, and the improvements made in its prognosis, therapeutic management, and the recent discovery of potential biomarkers associated with the diagnostic assay used for sarcoidosis confirmation.

Respiratory surveillance in mineral dust-exposed workers

Recently, there has been a worldwide resurgence in pneumoconiosis, or pulmonary fibrosis due to occupational mineral dust exposure. In Queensland, Australia, there has been a re-emergence of coal workers' pneumoconiosis and silicosis. Some coal mining communities have experienced a resurgence of progressive massive fibrosis in the USA and a worldwide epidemic is occurring of accelerated silicosis due to exposure to artificial stone.

These diseases are all preventable and should not be occurring in the 21st century. Best practice prevention includes reduction of exposure to mineral dusts or, ideally, prevention of exposure altogether. However, where dust exposure has occurred, respiratory surveillance can provide a strategy for early disease detection. It is important to identify early signs of occupational lung disease at a stage where intervention may be beneficial, though it must be acknowledged that progression may occur even after cessation of exposure to dusts. Respiratory surveillance should be distinguished from population screening and case finding, which are different methods used for disease investigation and control. Designing an ideal respiratory surveillance programme is challenging, as there is no single test that accurately identifies early disease. Several different respiratory disorders may occur related to the same exposure(s). Physicians organising and interpreting tests used in respiratory surveillance must be aware of the broad range of potential work-related respiratory conditions, complexities in diagnosis, and appropriate interpretation of the exposure history, as well as current management options. A working knowledge of the compensation and medicolegal avenues available to workers in individual jurisdictions is also useful.

Organising and interpreting respiratory surveillance for mineral dust-exposed workers requires specialist knowledge and understanding of the potential range of diseases, as well as a detailed occupational historyhttp://bit.ly/37KXSE4

Metabolomic and metallomic profile differences between Veterans and Civilians with Pulmonary Sarcoidosis

Sarcoidosis is a disorder characterized by granulomatous inflammation of unclear etiology. In this study we evaluated whether veterans with sarcoidosis exhibited different plasma metabolomic and metallomic profiles compared with civilians with sarcoidosis. A case control study was performed on veteran and civilian patients with confirmed sarcoidosis. Proton nuclear magnetic resonance spectroscopy (1H NMR), hydrophilic interaction liquid chromatography mass spectrometry (HILIC-MS) and inductively coupled plasma mass spectrometry (ICP-MS) were applied to quantify metabolites and metal elements in plasma samples. Our results revealed that the veterans with sarcoidosis significantly differed from civilians, according to metabolic and metallomics profiles. Moreover, the results showed that veterans with sarcoidosis and veterans with COPD were similar to each other in metabolomics and metallomics profiles. This study suggests the important role of environmental risk factors in the development of different molecular phenotypic responses of sarcoidosis. In addition, this study suggests that sarcoidosis in veterans may be an occupational disease.

Granulomatous lung disease in two workers making light bulbs

BACKGROUND

Associations between sarcoidosis or sarcoid-like granulomatous lung disease and exposure to silica and other inorganic agents have been suggested in several studies.

CASES

We describe granulomatous lung disease in two workers of a small production unit making metal-halide lamps. Initially, both were diagnosed with sarcoidosis. However, in both men, birefringent particles were observed in the lung or mediastinal lymph node biopsies. Clipping of glass tubes led to moderate exposure to dust, consisting mainly of amorphous fused silica, with some cristobalite. After removal from exposure, both subjects improved clinically, radiologically, and functionally.

CONCLUSION

The present cases support the hypothesis that silica might be a trigger for sarcoid-like granulomatous lung disease. Sarcoidosis should be considered a diagnosis of exclusion and clinicians should carefully collect occupational and environmental exposure histories to identify workplace triggers.

Moving target: shifting the focus to pulmonary sarcoidosis as an autoimmune spectrum disorder

Despite more than a century of research, the causative agent(s) in sarcoidosis, a heterogeneous granulomatous disorder mainly affecting the lungs, remain(s) elusive. Following identification of genetic factors underlying different clinical phenotypes, increased understanding of CD4⁺ T-cell immunology, which is believed to be central to sarcoid pathogenesis, as well as the role of B-cells and other cells bridging innate and adaptive immunity, contributes to novel insights into the mechanistic pathways influencing disease resolution or chronicity. Hopefully, new perspectives and state-of-the-art technology will help to shed light on the still-elusive enigma of sarcoid aetiology. This perspective article highlights a number of recent advances in the search for antigenic targets in sarcoidosis, as well as the main arguments for sarcoidosis as a spectrum of autoimmune conditions, either as a result of an external (microbial) trigger and/or due to defective control mechanisms regulating the balance between T-cell activation and inhibition.

Host-microbe interactions in the pathogenesis and clinical course of sarcoidosis

Sarcoidosis is a rare inflammatory disease characterized by the development of granulomas in various organs, especially in the lungs and lymph nodes. Clinics of the disease largely depends on the organ involved and may range from mild symptoms to life threatening manifestations. Over the last two decades, significant advances in the diagnosis, clinical assessment and treatment of sarcoidosis have been achieved, however, the precise etiology of this disease remains unknown. Current evidence suggests that, in genetically predisposed individuals, an excessive immune response to unknown antigen/s is crucial for the development of sarcoidosis. Epidemiological and microbiological studies suggest that, at least in a fraction of patients, microbes or their products may trigger the immune response leading to sarcoid granuloma formation. In this article, we discuss the scientific evidence on the interaction of microbes with immune cells that may be implicated in the immunopathogenesis of sarcoidosis, and highlight recent studies exploring potential implications of human microbiota in the pathogenesis and the clinical course of sarcoidosis.

A prospective study of patients diagnosed with sarcoidosis: factors - environmental exposure, health assessment, and genetic outlooks

This original research is a directional study that determined the habits of individuals using four analyses to find statistical significance in the data collected from the surveys of 801 qualified of 1,340 individuals who agreed to participate. Results from the self-reported diagnosis of individuals affected by sarcoidosis produced seven statistically significant indicators of future research needed. The demographics revealed a significantly greater number of women and African-Americans participants than other minorities in the United States and suggested a sense of urgency to find a cure. Most important are the seven statistically significant findings that also gave credence to the researchers' four subdiagnostic classifications. They are acute sarcoidosis (AS) and chronic sarcoidosis with limited dissemination (CSLD), while more severe cases include those with chronic sarcoidosis with full dissemination including cutaneous involvement (CSFDIC) and chronic sarcoidosis with neurosarcoidosis (CSN). The most severe sarcoidosis cases (CSN) were on the "most likely" side of every statistically significant category except drinking alcohol, and the "least likely" to participate in physical activities. Conversely, the least severe case of sarcoidosis (AS) was the opposite. The complete list of statistically significant areas was related to alcohol use, tobacco use, ciprofloxacin use, environmental exposure to metals (copper, iron), infectious diseases (candidiasis), genetics, and physical exercise. Statistically, the most crucial study needed; emerged from the Rh blood grouping of the participants.

Sarcoidosis in the Middle East

Sarcoidosis, a systemic granulomatous disease of unknown cause, has been described worldwide and in all populations with notable differences in clinical characteristics, organ involvement, disease severity, and prognosis among different ethnic and racial groups. While the exact prevalence of sarcoidosis in the Middle East is unknown, studies from various countries in the region have reported the clinical characteristics of affected patients, along with a few anecdotal reports. A search of the MEDLINE and Google Scholar databases was conducted for relevant English-language articles using the terms “sarcoidosis” and “Middle East” or “sarcoidosis” and “Arabs.” Subsequently, the names of individual countries were used as search terms, replacing “Middle East.” Overall, the clinical picture of patients with sarcoidosis in the Middle East is similar to that reported elsewhere; for example, the disease was more frequent among females and respiratory complaints were the predominant symptoms. Within the region, most patients from Oman were older and female, with arthralgia, hypercalcemia, and eye involvement being more common. Constitutional symptoms were frequent, especially among patients from Iran. Cough was more common among patients from Kuwait and Iran, while dyspnea was the predominant symptom for Saudi patients. Erythema nodosum was more common in the Turkish population. Clustering was seen in patients with Stage I and II of the disease in all countries except Oman. Apart from those in Iran, the prognosis of most patients from the Middle East was excellent.

Paediatric sarcoidosis

Paediatric sarcoidosis is an extremely rare disease characterized by a granulomatous inflammation. The estimated incidence is 0.6-1.02/100,000 children, but in the absence of international registers, the disease is probably under-reported. Its pathophysiologic basis is not clearly understood but the current hypothesis is a combination of a genetic predisposition and an environmental exposure that could be either organic or mineral. Contrary to adult forms of the disease, general symptoms are often at the forefront at diagnosis. In its most frequent form, paediatric sarcoidosis is a multi-organ disorder affecting preferentially the lungs, the lymphatic system and the liver, but all organs can be affected. This review aims to provide an overview of current knowledge on sarcoidosis in children, providing a summary of the data available from cohort studies on the presentation, the management and the evolution of the disease in this specific population.

Prevalence and incidence of sarcoidosis in Korea: a nationwide population-based study

BACKGROUND

The prevalence and incidence of sarcoidosis varies worldwide. We estimated the prevalence and incidence of sarcoidosis in Korea using nationwide claims data from the Korean Health Insurance Review and Assessment Service.

METHODS

Cases of sarcoidosis were identified for any visit between 2007 to 2016 that listed the Korean Classification of Disease, 7th edition code of sarcoidosis and rare incurable disease exempted calculation code. A narrow case definition was used as follows: 1) ≥ two sarcoidosis-coded visits within 1 year of the first claim, 2) no claims for other diseases that could form granuloma.

RESULTS

A total of 4791 patients (narrow, n = 2388) visited medical institutions for sarcoidosis during the study period; 2999 patients (narrow, n = 1696) were newly identified between 2009 and 2015. The sarcoidosis prevalence was 9.37 per 10⁵ people (narrow, 4.69) and was highest between ages 60-69 years. The incidence rate was 0.85 per 10⁵ population at risk (narrow, 0.48), with the highest incidence rate between ages 50-59 years. For incident cases (mean age: 48.5 year), the age distribution in whole population and females showed monophasic patterns peaking at aged 50-59 years, while males had biphasic incidence peak at aged 30-39 years and 60-69 years. The annual incidence rates showed increasing trends from 0.85 per 10⁵ population at risk in 2009 to 0.97 per 10⁵ population at risk in 2015.

CONCLUSIONS

In comparison with previous reports, the prevalence and incidence of sarcoidosis in Korea have increased and middle-aged women showed the highest risk.

Short-Term Particulate Air Pollution Exposure is Associated with Increased Severity of Respiratory and Quality of Life Symptoms in Patients with Fibrotic Sarcoidosis

This study aimed to determine if short-term exposure to particulate matter (PM_2.5) and ozone (O₃) is associated with increased symptoms or lung function decline in fibrotic sarcoidosis. Sixteen patients with fibrotic sarcoidosis complicated by frequent exacerbations completed pulmonary function testing and questionnaires every three months for one year. We compared 7-, 10-, and 14-day average levels of PM_2.5 and O₃ estimated at patient residences to spirometry (forced expiratory volume in 1 s (FEV1), to forced vital capacity (FVC), episodes of FEV1 decline > 10%) and questionnaire outcomes (Leicester cough questionnaire (LCQ), Saint George Respiratory Questionnaire (SGRQ), and King's Sarcoidosis Questionnaire (KSQ)) using generalized linear mixed effect models. PM_2.5 level averaged over 14 days was associated with lower KSQ general health status (score change -6.60 per interquartile range (IQR) PM_2.5 increase). PM_2.5 level averaged over 10 and 14 days was associated with lower KSQ lung specific health status (score change -6.93 and -6.91, respectively). PM_2.5 levels were not associated with FEV₁, FVC, episodes of FEV₁ decline > 10%, or respiratory symptoms measured by SGRQ or LCQ. Ozone exposure was not associated with any health outcomes. In this small cohort of patients with fibrotic sarcoidosis, PM_2.5 exposure was associated with increased severity of respiratory and quality of life symptoms.