A case control etiologic study of sarcoidosis: environmental and occupational risk factors

Cardiac sarcoidosis: diagnosis and management

Cardiac sarcoidosis is one of the most serious and unpredictable aspects of this disease state. Heart involvement frequently presents with arrhythmias or conduction disease, although myocardial infiltration resulting in congestive heart failure may also occur. The prognosis in cardiac sarcoidosis is highly variable, which relates to the heterogeneous nature of heart involvement and marked differences between racial groups. Electrocardiography and echocardiography often provide the first clue to the diagnosis, but advanced imaging studies using positron emission tomography and MRI, in combination with nuclear isotope perfusion scanning are now essential to the diagnosis and management of this condition. The identification of clinically occult cardiac sarcoidosis and the management of isolated and/or asymptomatic heart involvement remain both challenging and contentious. Corticosteroids remain the first treatment choice with the later substitution of immunosuppressive and steroid-sparing therapies. Heart transplantation is an unusual outcome, but when performed, the results are comparable or better than heart transplantation for other disease states. We review the epidemiology, developments in diagnostic techniques and the management of cardiac sarcoidosis.

Systemic Sarcoidosis Revealed by Axillary Electrolysis

Background:

Sarcoidosis is a noncaseating granulomatous disease that affects a large variety of organs and tissues. Skin sarcoidosis is commonly found in scar and tattooed tissues.

Objective:

To report this particular case of sarcoidosis following electrolysis hair removal.

Method:

We report the case of a woman who developed sarcoidosis years after axillary electrolysis hair removal.

Results:

The diagnosis of cutaneous sarcoidosis was suggested by the clinical manifestations and confirmed by histopathologic findings.

Conclusion:

Sarcoidosis should be considered during the investigation of skin lesions occurring in scar or traumatized tissue.

Sarcoidosis and cancer risk: systematic review and meta-analysis of observational studies

BACKGROUND

An increased cancer risk in patients with sarcoidosis has been suggested, although results are conflicting in a number of case-control and cohort studies. We conducted a systematic review of all available data and performed a meta-analysis to better define and quantify the association between sarcoidosis and cancer.

METHODS

We searched Medline and Embase for all original articles on cancer and sarcoidosis published up to January 2013. Two independent authors reviewed all titles/abstracts to identify studies according to predefined selection criteria. We derived summary estimates using a random-effects model and reported them as relative risk (RR). Publication bias was evaluated using a funnel plot and was quantified by the Egger test.

RESULTS

Sixteen original studies, involving > 25,000 patients, were included in the present review. The summary RR to develop all invasive cancers was 1.19 (95% CI, 1.07-1.32). The results for selected cancer sites indicated a significantly increased risk of skin (RR, 2.00; 95% CI, 1.69-2.36), hematopoietic (RR, 1.92; 95% CI, 1.41-2.62), upper digestive tract (RR, 1.73; 95% CI, 1.07-2.79), kidney (RR, 1.55; 95% CI, 1.21-1.99), liver (RR, 1.79; 95% CI, 1.03-3.11), and colorectal cancers (RR, 1.33; 95% CI, 1.07-1.67). There was no evidence of publication bias for all cancers (P = .9), nor for any specific cancer site.

CONCLUSIONS

The present meta-analysis suggests a significant, though moderate, association between sarcoidosis and malignancy.

Sarcoidosis mimicking metastatic thyroid cancer following radioactive iodine therapy

Introduction

Sarcoidosis is an inflammatory disease characterized by non-caseating granulomas that can be present in diverse organ systems. Sarcoidosis can be associated with malignancy, presenting either preceding, during, or after chemotherapy. We herewith report a case of sarcoidosis mimicking cancer recurrence that developed after radioactive iodine therapy for papillary thyroid cancer.

Background

A 68-year-old Caucasian woman was found to have an incidental mediastinal lymph node. She underwent biopsy, which revealed sarcoidosis. There was no further treatment or evidence of recurrence over the ensuing 9 years. She was then diagnosed with low-grade papillary thyroid cancer in the right posterior lobe and treated with total thyroidectomy followed by radioactive iodine therapy. Six months later, she was found to have elevated serum thyroglobulin. Post–remnant ablation scan showed increased tracer uptake in the bed of the thyroid. Though two thyroid ultrasound scans were negative, she was treated with I-131 for possible recurrence. She then developed right hip pain, prompting further investigation. Though a skeletal survey was negative, an 18-fluorodeoxyglucose positron emission tomography (PET) scan study revealed multiple hypermetabolic skeletal lesions in both humeri and the proximal left femur. In addition, hypermetabolic hilar and mediastinal nodes were noted. As widespread cancer metastasis was suspected, bone biopsy was performed, which showed non-caseating granulomas, consistent with recurrence of sarcoidosis.

Conclusion

Sarcoid lesions may mimic metastatic disease or recurrence in oncologic patients. Biopsy and histopathology examination should be performed to confirm the diagnosis. Recurrence or reactivation of sarcoidosis has been proposed to result from altered immunologic milieu because of the presence of either active cancer or its therapy. Teodorovic and colleagues postulated that the radioactive I-131 therapy leads to reduced secretion of Th2 cytokines such as interleukin (IL)-4, IL-5, and IL-13. Few case reports of sarcoidosis associated with papillary carcinoma have been published; this is the first report of systemic recurrence of sarcoidosis associated with papillary thyroid carcinoma after treatment with radioactive iodine therapy.

Age-related and historical changes in the clinical characteristics of sarcoidosis in Japan

BACKGROUND

National surveys conducted in Japan between 1960 and 2004 suggest a gradually increasing incidence of sarcoidosis in women >50 years old with increased involvement of the eye, skin, and heart. However, whether this involvement is due to the increased age at diagnosis is still unclear. We aimed here to identify the age-related differences in organ involvement in sarcoidosis in Japan, as well as the historical changes in clinical characteristics and the age-specific distribution of cases at diagnosis.

METHODS

We reviewed 588 consecutive Japanese patients newly diagnosed with sarcoidosis between 1974 and 2012 at Jichi Medical University Hospital. We compared organ involvement between subgroups differentiated by sex and age (<45 years; n = 275; ≥45 years; n = 313) at diagnosis and identified historical changes in the age-specific distribution in 10-year intervals.

RESULTS

Younger patients had more common involvement of extrathoracic lymph nodes, parotid/salivary gland, and liver, while older patients had more common involvement of non-lymphatic extrathoracic organs such as the eye, heart, muscle, and kidney. The age at diagnosis has consistently increased over the past four decades. The monophasic distribution in men has tended to become biphasic, and the biphasic distribution in women monophasic. Increasing trends were apparent for hypercalcemia and involvement of the gastrointestinal tract, skin, nervous system, muscle, and kidney.

CONCLUSIONS

Elderly patients at diagnosis had various extrathoracic involvement including eye, skin, and cardiac lesions. Moreover, the age at diagnosis of sarcoidosis has continued to increase in both sexes, influencing the recent trends in clinical characteristics.

Challenges in the diagnosis and treatment of neurosarcoidosis

The diagnosis and treatment of neurosarcoidosis can be very challenging for several reasons. It affects clinically 5%-10% of sarcoidosis patients, but can be found in up to 25% of autopsies. These data reveal that a high percentage of asymptomatic or misdiagnosed cases can be missed at an initial diagnostic approach. Clinical and imaging findings are often non-specific since they can be found in a large number of neurological disorders. Histopathology can also be confounding if not performed by an expert pathologist and not placed in an appropriate clinical context. In this review, we discuss clinical features, laboratory findings, imaging, and histology of neurosarcoidosis, and we report current evidence regarding drug therapy. We conclude that a correct diagnostic approach should include a multidisciplinary evaluation involving clinicians, radiologists, and pathologists and that future studies should evaluate the genetic signature of neurosarcoidosis as they could be helpful in the assessment of this uncommon disease. With head-to-head comparisons of medical treatment for neurosarcoidosis still lacking due to the rarity of the disease and an increasing number of immunomodulating therapies at hand, novel therapeutic approaches are to be expected within the next few years.

Annular sarcoidosis mimicking granuloma annulare: a case report

Cutaneous sarcoidosis is a great imitator and we have to remember this mimicker also in the differential diagnosis of erythematous annular lesions. We report the case of a 50-year- old man with a 7-year history of erythematous, annular or serpiginous, scaly plaques on his scalp, forehead, preauricular region and around his mouth who was misdiagnosed as granuloma annulare.

Sarcoidosis treatment with antifungal medication: a follow-up

INTRODUCTION

The aim of the study was to compare treatment of sarcoidosis with antifungal or corticosteroid medication.

METHODS

In patients with sarcoidosis antifungal medication (n = 29), corticosteroids (n = 21) or a combination (n = 27) was given. Nine patients allotted to antifungal medication were later given corticosteroids because of the lack of regression of the disease. X-ray scores for the severity of granuloma infiltration were determined. Chitotriosidase and angiotensin converting enzyme were determined. The time in months till remission was observed as well as the number of recurrences.

Interleukin-12 family cytokines and sarcoidosis

Sarcoidosis is a systemic granulomatous disease predominantly affecting the lungs. It is believed to be caused by exposure to pathogenic antigens in genetically susceptible individuals but the causative antigen has not been identified. The formation of non-caseating granulomas at sites of ongoing inflammation is the key feature of the disease. Other aspects of the pathogenesis are peripheral T-cell anergy and disease progression to fibrosis. Many T-cell-associated cytokines have been implicated in the immunopathogenesis of sarcoidosis, but it is becoming apparent that IL-12 cytokine family members including IL-12, IL-23, IL-27, and IL-35 are also involved. Although the members of this unique cytokine family are heterodimers of similar subunits, their biological functions are very diverse. Whilst IL-23 and IL-12 are pro-inflammatory regulators of Th1 and Th17 responses, IL-27 is bidirectional for inflammation and the most recent family member IL-35 is inhibitory. This review will discuss the current understanding of etiology and immunopathogenesis of sarcoidosis with a specific focus on the bidirectional impact of IL-12 family cytokines on the pathogenesis of sarcoidosis.

Cutaneous sarcoidosis: an intriguing model of immune dysregulation

Sarcoidosis is a systemic granulomatous disease characterized by the presence of non-caseating granulomas. Its etiology remains obscure. A plausible hypothesis suggests that a complex interplay of host factors, infectious processes, and non-infectious environmental factors, matched with a susceptible genetic background, results in a pathway that leads to systemic granulomatous inflammation. Although presentations of sarcoidosis vary enormously, multi-organ involvement is a common feature. Cutaneous involvement occurs in about 25% of patients with protean manifestations and variable prognoses. Skin manifestations are divided into specific lesions with histopathologically evident non-caseating granulomas and nonspecific lesions arising from a reactive process that does not form granulomas. A peculiar form of cutaneous sarcoidosis is represented by sarcoidal lesions at sites of trauma that has caused scarring. The pathogenesis of scar sarcoidosis remains unknown. Scar sarcoidosis is also associated with herpes zoster infection, surgery, and tattooing. Such heterogeneous events, along with those at the sites of chronic lymphedema, thermal burns, radiation dermatitis, and vaccinations, occur on areas of vulnerable skin labeled "immunocompromised districts". Numerous options are available for the treatment of cutaneous sarcoidosis. Although corticosteroids remain the treatment of choice for initial systemic therapy, other nonsteroidal agents have proven effective and therefore useful for long-term management. Tumor necrosis factor-α antagonists such as infliximab may have a role in the treatment of cutaneous sarcoidosis, especially in refractory cases that are resistant to standard regimens. Elucidation of the relationship of sarcoidal granulomas with malignancy and immunity may facilitate a better understanding of some pathomechanisms operating in neoplastic and immunity-related disorders.

Genetic susceptibility to beryllium: a case-referent study of men and women of working age with sarcoidosis or other chronic lung disease

OBJECTIVE

The study was designed to investigate whether beryllium exposure was related to illness diagnosed as sarcoidosis. Chronic beryllium disease (CBD) and sarcoidosis are clinically and pathologically indistinguishable, with only the presence of beryllium-specific T-lymphocytes identifying CBD. Testing for such cells is not feasible in community studies of sarcoidosis but a second characteristic of CBD, its much greater incidence in those with a glutamic acid residue at position 69 of the HLA-DPB1 gene (Glu69), provides an alternative approach to answering this question.

METHODS

Cases of sarcoidosis aged 18-60 years diagnosed in Alberta, Canada, from 1999 to 2005 were approached through their specialist physician, together with age-matched and sex-matched referents with other chronic lung disease. Referents were grouped into chronic obstructive pulmonary disease (COPD), asthma and other lung disease. Participants completed a telephone questionnaire, including industry-specific questionnaires. DNA was extracted from mailed-in mouthwash samples and genotyped for Glu69. Duration of employment in types of work with independently documented beryllium exposure was calculated.

RESULTS

DNA was extracted for 655 cases (270 Glu69 positive) and 1382 referents (561 positive). No increase in sarcoidosis was seen with either Glu69 or beryllium exposure (none, <10, ≥10 years) as main effects: longer duration in possible beryllium jobs was related to COPD. In Glu69 positive men with exposure ≥10 years, the trend towards increasing rate of COPD was reversed, and a significant interaction of duration of exposure and Glu69 was detected (OR=4.51 95% CI 1.17 to 17.48).

CONCLUSIONS

The gene-environment interaction supports the hypothesis that some cases diagnosed as sarcoidosis result from occupational beryllium exposure.

Assessment of cardiac sarcoidosis with advanced imaging modalities

Sarcoidosis is a chronic systemic disease of unknown etiology that is characterized by the presence of noncaseating epithelioid granulomas, usually in multiple organs. Several studies have shown that sarcoidosis might be the result of an exaggerated granulomatous reaction after exposure to unidentified antigens in genetically susceptible individuals. Cardiac involvement may occur and lead to an adverse outcome: the heart mechanics will be affected and that causes ventricular failure, and the cardiac electrical system will be disrupted and lead to third degree atrioventricular block, malignant ventricular tachycardia, and sudden cardiac death. Thus, early diagnosis and treatment of this potentially devastating disease is critically important. However, sensitive and accurate imaging modalities have not been established. Recent studies have demonstrated the promising potential of cardiac magnetic resonance imaging (MRI) and (18)F-fluoro-2-deoxyglucose positron emission tomography ((18)F-FDG PET) in the diagnosis and assessment of cardiac sarcoidosis (CS). In this review, we discuss the epidemiology, etiology, histological findings, and clinical features of sarcoidosis. We also introduce advanced imaging including (18)F-FDG PET and cardiac MRI as more reliable diagnostic modalities for CS.

Fungal exposure and low levels of IL-10 in patients with sarcoidosis

BACKGROUND AND OBJECTIVES

Sarcoidosis is an inflammatory disease with increased levels of inflammatory cytokines. Previous studies have shown a relation between the degree of granuloma infiltration and serum cytokine levels, except for interleukin- (IL-) 10. The aim of the study was to further investigate the serum levels of IL-10 in patients with sarcoidosis and relate them to fungal exposure in terms of the amount of fungi in the air of their homes and β-glucan in bronchoalveolar lavage (BAL) fluid.

METHODS

Patients with sarcoidosis (n = 71) and healthy controls (n = 27) were enrolled. IL-10 was determined in serum. BAL was performed and the amount of β-glucan was measured. Domestic exposure to fungi was determined by measuring airborne β-N-acetylhexosaminidase (NAHA) in the bedrooms.

RESULTS

At high levels of fungal exposure (domestic fungal exposure and β-glucan in BAL), serum IL-10 values were lower than at low and intermediate exposure levels.

CONCLUSION

The low serum IL-10 values at high fungal exposure suggest that fungal cell wall agents play a role in granuloma formation in sarcoidosis by inhibiting the secretion of the anti-inflammatory cytokine IL-10.

Proteomic changes of alveolar lining fluid in illnesses associated with exposure to inhaled non-infectious microbial particles

Background

Hyperresponsiveness to inhaled non-infectious microbial particles (NIMPs) has been associated with illnesses in the airways. Hypersensitivity pneumonitis (HP) is considered to be the prototype for these NIMPs-related diseases; however, there is no consensus on the definitions or diagnostic criteria for HP and the spectrum of related illnesses.

Methods and Findings

In order to identify the possible diagnostic markers for illnesses associated with NIMPs in alveolar lining fluid, we performed a proteomic analysis using a two-dimensional difference gel electrophoresis on bronchoalveolar lavage (BAL) fluid from patients with exposure to NIMPs in the context of damp building-related illness (DBRI) or conditions on the borderline to acute HP, designated here as agricultural type of microbial exposure (AME). Samples from patients with HP and sarcoidosis (SARC) were included for reference. Results were compared to results of healthy subjects (CTR). Western blot was used for validation of potential marker proteins from BAL fluid and plasma. Protein expression patterns suggest a close similarity between AME and HP, while DBRI was similar to CTR. However, in DBRI the levels of the inflammation associated molecules galectin-3 and alpha-1-antitrypsin were increased. A novel finding emerging from this study was the increases of semenogelin levels in BAL fluid from patients with AME, HP and SARC. Histone 4 levels were increased in AME, HP and SARC. Elevated plasma levels of histone 2B were detected in HP and SARC, suggesting it to be a potential blood indicator for inflammatory diseases of the lungs.

Conclusions

In this study, the proteomic changes in bronchoalveolar lavage of DBRI patients were distinct from other NIMP exposure associated lung diseases, while changes in AME overlapped those observed for HP patient samples. Some of the proteins identified in this study, semenogelin and histone 4, could function as diagnostic markers for differential diagnosis between DBRI and HP-like conditions.

Current best practice in the management of pulmonary and systemic sarcoidosis

Sarcoidosis is a systemic inflammatory disease of unknown etiology that is characterized by the presence of granulomatous inflammation in affected tissues. It can affect essentially any organ system but shows a predilection for the lungs, eyes, and skin. Accurate epidemiological data are not available in the USA, but sarcoidosis is considered a 'rare disease' (prevalence less than 200,000). However, recent epidemiologic studies indicate that regional prevalence is much higher than previously estimated, especially among African American women. Additionally, mortality rates of patients with sarcoidosis are increasing by 3% per year over the past two decades. The most common causes of death are attributed to progressive lung disease and cardiac sarcoidosis, and the health of the patients is further compromised by other systemic manifestations. As such, the management of sarcoidosis requires a collaborative multidisciplinary approach. We aim to discuss the principles of managing sarcoidosis, including standards of care relating to pulmonary disease as well as recent advances relating to the detection and treatment of extrapulmonary manifestations.

Prevalence and clinical picture of musculoskeletal sarcoidosis

Background:

Sarcoidosis is a multisystem disease affecting different organs with different frequency rates depending on geographical location. Musculoskeletal abnormalities includes osseous lesions (small and large bone sarcoidosis), sarcoidal arthropathy, and sarcoidal myopathy. Musculoskeletal involvement is reported in a significant number of patients.

Objectives:

This study aimed to determine the prevalence and clinical picture of musculoskeletal sarcoidosis in Iranian cohort of patients with sarcoidosis.

Patients and Methods:

We designed a descriptive cross-sectional study including 30 patients with sarcoidosis who had hospitalized in the Rheumatology Department at Ghaem Hospital, Mashhad, Iran. The patients were evaluated for musculoskeletal symptoms using history, physical examination, and paraclinical data.

Results:

Of the 30 studied patients, 24 were female (80%) and six were male (20%). The mean age at diagnosis was 38 years. Sarcoidal arthropathy (arthritis and periarthritis) was observed in 26 patients (86.6%). Furthermore, the initial presentation was associated with joint symptoms in 19 cases (63.3%); acute arthritis developed in 17 (65%) while bone and muscle involvements each occurred in 2 (6.6%).

Conclusions:

Sarcoidosis is a common disease in women aged 20 to 40 years. The most common involved joint were consecutively ankles, knees, and wrists, reaching a accumulated frequency of 86.6%; however, bone and muscle involvements were uncommon.

Epidemiology of sarcoidosis in Afro-Caribbean people: a 7-year retrospective study in Guadeloupe

BACKGROUND

There are no reliable epidemiological data on sarcoidosis in the French West Indies, although this disease is known to be more frequent and more severe in Black African-Americans and West Indians.

OBJECTIVES

This retrospective study aimed to assess the incidence and prevalence of sarcoidosis in Guadeloupe over a 7-year period and to determine its epidemiological, clinical, and evolutionary characteristics.

METHODS

Patients were identified through the computerized databases of the three pathology laboratories and two hospitals on the islands of Guadeloupe. Histologically proven cases of sarcoidosis were selected. All patients were recalled at a single study time-point.

RESULTS

A total of 75 patients were identified. These included 44 women and 31 men (sex ratio: 1.4), with a mean ± standard deviation (SD) age of 47 ± 14 years and Fitzpatrick skin types IV-VI. The average incidence was 2.28 per 100,000 inhabitants per year (95% confidence interval [CI] 1.69-3.02). The prevalence of sarcoidosis in 2009 was 21.09 per 100,000 inhabitants (95% CI 16.00-26.18). Most patients (61/71, 85.9%) exhibited multiple organ involvement; the mean ± SD number of organs involved was 2.6 ± 1.1. The initiation of systemic therapy was required in 75.7% of cases. Several lines of treatment were necessary in 41.5% of affected patients. At the study time-point, seven patients were found to have died. Four of these deaths were directly attributable to sarcoidosis (mortality rate: 5.3%).

CONCLUSIONS

This epidemiological study on sarcoidosis in Guadeloupe reveals a low incidence of the disease and a high degree of severity as evidenced by the average number of affected organs, the high frequency of extrathoracic organ involvement, the frequent use of corticosteroids, and a mortality rate of 5.3%.

Carbon Nanotubes and Chronic Granulomatous Disease

Use of nanomaterials in manufactured consumer products is a rapidly expanding industry and potential toxicities are just beginning to be explored. Combustion-generated multiwall carbon nanotubes (MWCNT) or nanoparticles are ubiquitous in non-manufacturing environments and detectable in vapors from diesel fuel, methane, propane, and natural gas. In experimental animal models, carbon nanotubes have been shown to induce granulomas or other inflammatory changes. Evidence suggesting potential involvement of carbon nanomaterials in human granulomatous disease, has been gathered from analyses of dusts generated in the World Trade Center disaster combined with epidemiological data showing a subsequent increase in granulomatous disease of first responders. In this review we will discuss evidence for similarities in the pathophysiology of carbon nanotube-induced pulmonary disease in experimental animals with that of the human granulomatous disease, sarcoidosis.

Accelerator mass spectrometry detection of beryllium ions in the antigen processing and presentation pathway

Exposure to small amounts of beryllium (Be) can result in beryllium sensitization and progression to Chronic Beryllium Disease (CBD). In CBD, beryllium is presented to Be-responsive T-cells by professional antigen-presenting cells (APC). This presentation drives T-cell proliferation and pro-inflammatory cytokine (IL-2, TNFα, and IFNγ) production and leads to granuloma formation. The mechanism by which beryllium enters an APC and is processed to become part of the beryllium antigen complex has not yet been elucidated. Developing techniques for beryllium detection with enough sensitivity has presented a barrier to further investigation. The objective of this study was to demonstrate that Accelerator Mass Spectrometry (AMS) is sensitive enough to quantify the amount of beryllium presented by APC to stimulate Be-responsive T-cells. To achieve this goal, APC - which may or may not stimulate Be-responsive T-cells - were cultured with Be-ferritin. Then, by utilizing AMS, the amount of beryllium processed for presentation was determined. Further, IFNγ intracellular cytokine assays were performed to demonstrate that Be-ferritin (at levels used in the experiments) could stimulate Be-responsive T-cells when presented by an APC of the correct HLA type (HLA-DP0201). The results indicated that Be-responsive T-cells expressed IFNγ only when APC with the correct HLA type were able to process Be for presentation. Utilizing AMS, it was determined that APC with HLA-DP0201 had membrane fractions containing 0.17-0.59 ng Be and APC with HLA-DP0401 had membrane fractions bearing 0.40-0.45 ng Be. However, HLA-DP0401 APC had 20-times more Be associated with the whole cells (57.68-61.12 ng) than HLA-DP0201 APC (0.90-3.49 ng). As these findings demonstrate, AMS detection of picogram levels of Be processed by APC is possible. Further, regardless of form, Be requires processing by APC to successfully stimulate Be-responsive T-cells to generate IFNγ.

Overexpression of IL-17RC associated with ocular sarcoidosis

Background

Sarcoidosis is a chronic inflammatory disease with a systemic granulomatous disorder affecting multiple organs including the eye. Both CD4⁺ T cell and macrophage have been linked to the pathogenesis of the disease.

Methods

The expression of IL-17RC was measured using FACS,immunohistochemistry and real-time PCR. Serum level of IL-17 was detected using ELISA.

Results

An elevated expression of IL-17RC on CD8⁺ T cells in peripheral blood was found in patients with ocular sarcoidosis as compared to healthy controls. Interestingly, we found a significant increase in the serum level of IL-17 in patients with ocular sarcoidosis as compared to healthy controls, which may be responsible for the induction of IL-17RC on CD8⁺ cells. In addition, IL-17RC appeared only in the retinal tissue of the patient with clinically active sarcoidosis.

Conclusions

Our results suggested a potential involvement of IL-17RC⁺CD8⁺ T cells in pathogenesis of ocular sarcoidosis.

Efficient generalized least squares method for mixed population and family-based samples in genome-wide association studies

Genome-wide association studies (GWAS) that draw samples from multiple studies with a mixture of relationship structures are becoming more common. Analytical methods exist for using mixed-sample data, but few methods have been proposed for the analysis of genotype-by-environment (G×E) interactions. Using GWAS data from a study of sarcoidosis susceptibility genes in related and unrelated African Americans, we explored the current analytic options for genotype association testing in studies using both unrelated and family-based designs. We propose a novel method-generalized least squares (GLX)-to estimate both SNP and G×E interaction effects for categorical environmental covariates and compared this method to generalized estimating equations (GEE), logistic regression, the Cochran-Armitage trend test, and the WQLS and MQLS methods. We used simulation to demonstrate that the GLX method reduces type I error under a variety of pedigree structures. We also demonstrate its superior power to detect SNP effects while offering computational advantages and comparable power to detect G×E interactions versus GEE. Using this method, we found two novel SNPs that demonstrate a significant genome-wide interaction with insecticide exposure-rs10499003 and rs7745248, located in the intronic and 3' UTR regions of the FUT9 gene on chromosome 6q16.1.

Gene expression profiles in granuloma tissue reveal novel diagnostic markers in sarcoidosis

Sarcoidosis is an immune-mediated multisystem disease characterized by the formation of non-caseating granulomas. The pathogenesis of sarcoidosis is unclear, with proposed infectious or environmental antigens triggering an aberrant immune response in susceptible hosts. Multiple pro-inflammatory signaling pathways have been implicated in mediating macrophage activation and granuloma formation in sarcoidosis, including IFN-γ/STAT-1, IL-6/STAT-3, and NF-κB. It is difficult to distinguish sarcoidosis from other granulomatous diseases or assess disease severity and treatment response with histopathology alone. Therefore, development of improved diagnostic tools is imperative. Herein, we describe an efficient and reliable technique to classify granulomatous disease through selected gene expression and identify novel genes and cytokine pathways contributing to the pathogenesis of sarcoidosis. We quantified the expression of twenty selected mRNAs extracted from formalin-fixed paraffin embedded (FFPE) tissue (n = 38) of normal lung, suture granulomas, sarcoid granulomas, and fungal granulomas. Utilizing quantitative real-time RT-PCR we analyzed the expression of several genes, including IL-6, COX-2, MCP-1, IFN-γ, T-bet, IRF-1, Nox2, IL-33, and eotaxin-1 and revealed differential regulation between suture, sarcoidosis, and fungal granulomas. This is the first study demonstrating that quantification of target gene expression in FFPE tissue biopsies is a potentially effective diagnostic and research tool in sarcoidosis.

Sarcoidosis

Sarcoidosis is a systemic disease of unknown cause that is characterised by the formation of immune granulomas in various organs, mainly the lungs and the lymphatic system. Studies show that sarcoidosis might be the result of an exaggerated granulomatous reaction after exposure to unidentified antigens in individuals who are genetically susceptible. Several new insights have been made, particularly with regards to the diagnosis and care of some important manifestations of sarcoidosis. The indications for endobronchial ultrasound in diagnosis and for PET in the assessment of inflammatory activity are now better specified. Recognition of unexplained persistent disabling symptoms, fatigue, small-fibre neurological impairment, cognitive failure, and changes to health state and quality of life, has improved. Mortality in patients with sarcoidosis is higher than that of the general population, mainly due to pulmonary fibrosis. Predicted advances for the future are finding the cause of sarcoidosis, and the elucidation of relevant biomarkers, reliable endpoints, and new efficient treatments, particularly in patients with refractory sarcoidosis, lung fibrosis, and those with persistent disabling symptoms.

Inflammatory markers and pulmonary granuloma infiltration in sarcoidosis

BACKGROUND AND OBJECTIVE

Previous studies have demonstrated increases of inflammatory mediators in sarcoidosis while epidemiological studies have also demonstrated an association with increased fungi exposure. This study measured the level of β-glucan in the lungs and of inflammatory mediators in serum, and correlated both with the extent of pulmonary granuloma infiltration.

METHODS

This is a cross-sectional study of 98 patients with sarcoidosis and 26 controls. β-glucan, a cell wall constituent of fungi, was measured in bronchoalveolar lavage. Inflammatory mediator levels were determined in serum. The extent of granuloma infiltration was estimated on the chest X-ray. Exposure to fungi at home was determined by taking air samples in bedrooms and analysing for the presence of β-N-acetylhexosaminidase.

RESULTS

Significantly, higher levels of β-glucan were found in broncho-alveolar lavage in subjects with sarcoidosis as compared with controls. There were significant positive relationships between the extent of granuloma infiltration and the levels of the different inflammatory mediators, except for interleukin-10. Domestic fungal exposure was higher among subjects with sarcoidosis.

CONCLUSIONS

This is the first time that a specific agent, previously suspected to be related to the risk of sarcoidosis, has been detected in the lung of subjects with sarcoidosis and related to the levels of inflammatory mediators and the degree of home exposure to fungi. The results suggest that exposure to fungi should be explored when investigating patients with sarcoidosis.

Molecular analysis of sarcoidosis lymph nodes for microorganisms: a case-control study with clinical correlates

INTRODUCTION

Sarcoidosis is an incurable, chronic granulomatous disease primarily involving the lungs and lymph nodes of unknown aetiology, treated with non-specific anti-inflammatory/immunosuppressive drugs. Persistently symptomatic patients worsen with a disabling, potentially fatal clinical course. To determine a possible infectious cause, we correlated in a case-control study the clinical information with the presence of bacterial DNA in sarcoidosis mediastinal lymph nodes compared with control lymph nodes resected during cancer surgery.

METHODS

We retrospectively studied formalin-fixed, paraffin-embedded, mediastinal lymph nodes from 30 patients with sarcoidosis and 30 control patients with lung cancer. Nucleic acids were extracted from nodes, evaluated by ribosomal RNA PCR for bacterial 16S ribosomal DNA and the results were sequenced and compared with a bacterial sequence library. Clinical information was correlated.

RESULTS

11/30 (36.7%) of lymph nodes from patients with sarcoidosis had detectable bacterial DNA, significantly more than control patient lymph nodes (2/30, 6.7%), p=0.00516. At presentation, 19/30 (63.3%) patients with sarcoidosis were symptomatic including all patients with detectable bacterial DNA. Radiographically, there were 18 stage I and 12 stage II patients. All stage II patients were symptomatic and 75% had PCR-detectable bacteria. After a mean follow-up of 52.8±32.8 months, all patients with PCR-detectable bacteria in this series were persistently symptomatic requiring treatment.

DISCUSSION

36.6% of patients with sarcoidosis had detectable bacterial DNA on presentation, all of these patients were quite symptomatic and most were radiographically advanced stage II. These findings suggest that bacterial DNA-positive, symptomatic patients have more aggressive sarcoidosis that persists long term and might benefit from antimicrobial treatment directed against this presumed chronic granulomatous infection.

Granuloma formation in pulmonary sarcoidosis

Sarcoidosis is a granulomatous disorder of unknown cause, affecting multiple organs, but mainly the lungs. The exact order of immunological events remains obscure. Reviewing current literature, combined with careful clinical observations, we propose a model for granuloma formation in pulmonary sarcoidosis. A tight collaboration between macrophages, dendritic cells, and lymphocyte subsets, initiates the first steps toward granuloma formation, orchestrated by cytokines and chemokines. In a substantial part of pulmonary sarcoidosis patients, granuloma formation becomes an on-going process, leading to debilitating disease, and sometimes death. The immunological response, determining granuloma sustainment is not well understood. An impaired immunosuppressive function of regulatory T cells has been suggested to contribute to the exaggerated response. Interestingly, therapeutical agents commonly used in sarcoidosis, such as glucocorticosteroids and anti-TNF agents, interfere with granuloma integrity and restore the immune homeostasis in autoimmune disorders. Increasing insight into their mechanisms of action may contribute to the search for new therapeutical targets in pulmonary sarcoidosis.

Immunopathogenesis of sarcoidosis and risk of malignancy: a lost truth?

The hypothesis of a relationship between sarcoidosis and malignancy was firstly formulated in 1972 by Brincker. He documented an association of sarcoid reactions or sarcoidosis with 19 lymphomas and associated malignancies. Based on various epidemiological studies, for more than 20 years sarcoidosis has been considered as a condition at increased risk for cancer, particularly lymphoproliferative disorders. The existence of a sarcoidosis-lymphoma syndrome was therefore proposed, highlighting, as a potential mechanism, the uncontrolled lymphocyte proliferation and mitotic activity. A reduced ability to eliminate an antigen and chronic inflammation have been suggested as triggering events. Leading to a reduced tumor immune surveillance, a diminished myeloid dendritic cells (mDC) function, despite up-regulated co-stimulatory and maturation markers, was also raised as potential mechanism. However, some subsequent studies have questioned the presence of a close association between the two entities and have explained those previously published as the result of selection bias and misclassification. Recently, a Swedish population-based cohort study documented a significant overall excess incidence of cancer among sarcoidosis patients, especially those with multiple hospitalizations or admission in older age, emphasizing again a potential neoplastic risk. Therefore, currently, whether these patients have an increased risk of developing malignant lesions is still debated. Larger and unbiased studies are needed before drawing definite conclusions.

Hepatic Sarcoidosis

Sarcoidosis is a multisystem disease characterized by the presence of non-caseating granulomas in affected organs. Pulmonary involvement is the most common site of disease activity. However, hepatic involvement is also common in sarcoidosis, occurring in up to 70% of patients. Most patients with liver involvement are asymptomatic. Therefore, the majority of cases are discovered incidentally, frequently by the finding of elevated liver enzymes. Pain in the right upper quadrant of the abdomen, fatigue, pruritus, and jaundice may be associated with liver involvement. Portal hypertension and cirrhosis are complications linked to long-standing hepatic sarcoidosis. Liver biopsy is usually required to confirm the diagnosis. It is important to differentiate hepatic sarcoidosis from other autoimmune and granulomatous liver diseases. Not all cases of hepatic sarcoidosis require treatment. For symptomatic patients, the first line treatment includes corticosteroids or ursodeoxycholic acid. Various immunosuppressant agents can be used as second line agents. Rarely, severe cases require liver transplantation.

Occupational pesticide exposures and respiratory health

Pesticides have been widely used to control pest and pest-related diseases in agriculture, fishery, forestry and the food industry. In this review, we identify a number of respiratory symptoms and diseases that have been associated with occupational pesticide exposures. Impaired lung function has also been observed among people occupationally exposed to pesticides. There was strong evidence for an association between occupational pesticide exposure and asthma, especially in agricultural occupations. In addition, we found suggestive evidence for a link between occupational pesticide exposure and chronic bronchitis or COPD. There was inconclusive evidence for the association between occupational pesticide exposure and lung cancer. Better control of pesticide uses and enforcement of safety behaviors, such as using personal protection equipment (PPE) in the workplace, are critical for reducing the risk of developing pesticide-related symptoms and diseases. Educational training programs focusing on basic safety precautions and proper uses of personal protection equipment (PPE) are possible interventions that could be used to control the respiratory diseases associated with pesticide exposure in occupational setting.

Advanced imaging of cardiac sarcoidosis

Sarcoidosis is a systemic granulomatous disease of unknown etiology. Cardiac involvement may occur, leading to an adverse outcome. Although early treatment to improve morbidity and mortality is desirable, sensitive and accurate detection of cardiac sarcoidosis remains a challenge. Accordingly, interest in the use of advanced imaging such as cardiac MR and PET with (18)F-FDG is increasing in order to refine the clinical workup. Although the field is still facing challenges and uncertainties, this article presents a summary of clinical background and the current state of diagnostic modalities and treatment of cardiac sarcoidosis.

Adalimumab induced pulmonary sarcoid reaction

Sarcoidosis is a multisystem granulomatous inflammatory disease of unknown etiology. There is evidence that Tumor Necrosis Factor alpha (TNF-α) antagonists are useful in the treatment of advanced or refractory disease. However, sarcoidosis-like reaction has been reported with TNF-α blockade in other inflammatory conditions. Here we report a case of sarcoid-like reaction in a patient with psoriatic arthritis shortly after initiation of adalimumab therapy. Stopping adalimumab and systemic anti-inflammatory therapy with corticosteroids resulted in resolution of pulmonary symptoms and chest radiographic findings. Though TNF-α plays a critical role in pathogenesis of sarcoidosis, the development of sarcoid reaction with TNF-α blockade is paradoxical and the mechanism of this response remains unknown. TNF-α induced sarcoid-reaction could involve multiple organs. Its development with one agent does not preclude therapy with other TNF-α blockers.

Renal sarcoidosis with limited lung manifestations expressing Propionibacterium acnes antigens in the affected tubulointerstitium

Sarcoidosis is a granulomatous multisystemic disorder of unknown origin that can affect the kidneys. Previous reports from Japan and Europe have indicated a link between Propionibacterium acnes infections and sarcoidosis. Here, we present the case of a 68-year-old woman with hypercalcemia and renal failure. A kidney biopsy was performed, which showed granulomatous tubulointerstitial nephritis with a large nonnecrotic nodule that contained mononuclear inflammatory cells and multinucleated giant cells. Subsequent immunohistochemical analysis revealed intracytoplasmic structures, which strongly indicated the presence of the P acnes antigen. Treatment with methylprednisolone ameliorated the patient's hypercalcemia and renal failure. This case report emphasizes the potential of chronic P acnes infection to cause sarcoidosis.

Isolated cervical lymph node sarcoidosis presenting in an asymptomatic neck mass: a case report

Sarcoidosis, a systemic granulomatous disease of unknown etiology. The presentation of sarcoidal granuloma in neck nodes without typical manifestations of systemic sarcoidosis is difficult to diagnose. We describe the case of a 37-year-old woman with an increasing mass on the right side of neck. The excisional biopsy from the neck mass showed noncaseating epithelioid cell granuloma of the lymph nodes. No evidence of mycobacterial or fungal infection was noted. Thoracic evaluations did not show enlargement of mediastinal lymph nodes or parenchymal abnormalities. Immunohistochemistry showed abundant expression of tumor necrosis factor-α in the granuloma. However, transforming growth factor-β was not expressed, although interleukin-1β was focally expressed. These immunohistochemical findings supported characterization of the granuloma and the diagnosis of sarcoidosis. Sarcoidosis can present with cervical lymph node enlargement without mediastinal or lung abnormality. Immunohistochemistry may support the diagnosis of sarcoidosis and characterization of granuloma.

ICAM-1 deficiency exacerbates sarcoid-like granulomatosis induced by Propionibacterium acnes through impaired IL-10 production by regulatory T cells

Propionibacterium acnes has been implicated as one of the suggested causative antigens for sarcoidosis, a systemic granulomatous disease. By injecting heat-killed P. acnes into the dorsal skin of C57BL/6J mice on days 1, 3, 5, and 14, sarcoid-like granulomatosis was induced in skin and lungs of these mice on day 28. To clarify the role of cell adhesion molecules in cutaneous sarcoidosis, we induced sarcoid-like granulomatosis in mice deficient of intercellular adhesion molecule (ICAM)-1, L-selectin, P-selectin, or E-selectin via repeated P. acnes injection. Histopathologic analysis revealed that granuloma formation was aggravated in the skin and lungs of ICAM-1-deficient mice compared with wild-type mice. Within skin granulomas of ICAM-1-deficient mice, P. acnes immunization up-regulated mRNA expression of tumor necrosis factor-α, although it failed to induce IL-10 mRNA expression in contrast to wild-type mice. Infiltration of regulatory T cells into skin granuloma was similar between wild-type mice and ICAM-1-deficient mice. P. acnes immunization induced IL-10 production by CD4(+)CD25(+)Foxp3(+) regulatory T cells in lymph nodes of wild-type mice in vivo, which was absent in regulatory T cells of ICAM-1-deficient mice. Our results indicate that ICAM-1 is imperative for inducing regulatory T cells to produce IL-10 in vivo, which would prevent granuloma formation.

Transcriptional blood signatures distinguish pulmonary tuberculosis, pulmonary sarcoidosis, pneumonias and lung cancers

RATIONALE

New approaches to define factors underlying the immunopathogenesis of pulmonary diseases including sarcoidosis and tuberculosis are needed to develop new treatments and biomarkers. Comparing the blood transcriptional response of tuberculosis to other similar pulmonary diseases will advance knowledge of disease pathways and help distinguish diseases with similar clinical presentations.

OBJECTIVES

To determine the factors underlying the immunopathogenesis of the granulomatous diseases, sarcoidosis and tuberculosis, by comparing the blood transcriptional responses in these and other pulmonary diseases.

METHODS

We compared whole blood genome-wide transcriptional profiles in pulmonary sarcoidosis, pulmonary tuberculosis, to community acquired pneumonia and primary lung cancer and healthy controls, before and after treatment, and in purified leucocyte populations.

MEASUREMENTS AND MAIN RESULTS

An Interferon-inducible neutrophil-driven blood transcriptional signature was present in both sarcoidosis and tuberculosis, with a higher abundance and expression in tuberculosis. Heterogeneity of the sarcoidosis signature correlated significantly with disease activity. Transcriptional profiles in pneumonia and lung cancer revealed an over-abundance of inflammatory transcripts. After successful treatment the transcriptional activity in tuberculosis and pneumonia patients was significantly reduced. However the glucocorticoid-responsive sarcoidosis patients showed a significant increase in transcriptional activity. 144-blood transcripts were able to distinguish tuberculosis from other lung diseases and controls.

CONCLUSIONS

Tuberculosis and sarcoidosis revealed similar blood transcriptional profiles, dominated by interferon-inducible transcripts, while pneumonia and lung cancer showed distinct signatures, dominated by inflammatory genes. There were also significant differences between tuberculosis and sarcoidosis in the degree of their transcriptional activity, the heterogeneity of their profiles and their transcriptional response to treatment.

Sarcoidosis: Immunopathogenesis and Immunological Markers

Sarcoidosis is a multisystem granulomatous disorder invariably affecting the lungs. It is a disease with noteworthy variations in clinical manifestation and disease outcome and has been described as an “immune paradox” with peripheral anergy despite exaggerated inflammation at disease sites. Despite extensive research, sarcoidosis remains a disease with undetermined aetiology. Current evidence supports the notion that the immune response in sarcoidosis is driven by a putative antigen in a genetically susceptible individual. Unfortunately, there currently exists no reliable biomarker to delineate the disease severity and prognosis. As such, the diagnosis of sarcoidosis remains a vexing clinical challenge. In this review, we outline the immunological features of sarcoidosis, discuss the evidence for and against various candidate etiological agents (infective and noninfective), describe the exhaled breath condensate, a novel method of identifying immunological biomarkers, and suggest other possible immunological biomarkers to better characterise the immunopathogenesis of sarcoidosis.

Nicotine treatment improves Toll-like receptor 2 and Toll-like receptor 9 responsiveness in active pulmonary sarcoidosis

BACKGROUND

New evidence links nicotine to the regulation of T cell-mediated inflammation via a 7 nicotinic cholinergic receptor activation, and chronic nicotine exposure (smoking) reduces the incidence of granulomatous diseases. We sought to determine whether nicotine treatment was well tolerated while effectively normalizing immune responses in patients with active pulmonary sarcoidosis.

METHODS

Consenting adults with symptomatic sarcoidosis (n 5 13) were randomly assigned to receive 12 weeks of nicotine treatment plus conventional therapy or conventional therapy alone. Obtained blood cells were evaluated for their responsiveness to selected Toll-like receptor (TLR) and nucleotide oligomerization domain-like receptor ligands and T cell surface marker expression before and after nicotine treatment. Asymptomatic patients (n 5 6) and disease-free subjects (n 5 6) served as comparative control subjects. Adverse events were monitored for the duration of the study.

RESULTS

Compared with the asymptomatic group, symptomatic patients had impaired peripheral responses to TLR2, TLR4, and TLR9 ligands (anergy) and reduced peripheral populations of CD4 1 FoxP3 1 regulatory T cells (Tregs). Nicotine treatment was associated with restoration of TLR2 and TLR9 responsiveness, and expansion of Tregs, including the CD4 1 CD25 2 FoxP3 1 phenotype. There were no serious adverse events or signs of nicotine dependency.

CONCLUSIONS

Nicotine treatment in active pulmonary sarcoidosis was well tolerated and restored peripheral immune responsiveness to TLR2 and TLR9 agonists and expansion of FoxP3 1 Tregs, including a specific “preactivated” (CD25 2 ) phenotype. The immune phenotype of patients with symptomatic sarcoidosis treated with nicotine closely resembled that of asymptomatic patients, supporting the notion that nicotine treatment may be beneficial in this patient population.

Etiologic aspect of sarcoidosis as an allergic endogenous infection caused by Propionibacterium acnes

Sarcoidosis is a systemic granulomatous disease of unknown etiology. Propionibacterium acnes is the only microorganism that has been isolated from sarcoid lesions. Many P. acnes have been detected in sarcoid lymph nodes using quantitative PCR and in sarcoid granulomas by in situ hybridization. P. acnes trigger factor protein causes a cellular immune response only in sarcoid patients and induces pulmonary granulomas in mice sensitized with the protein and adjuvant, but only those with latent P. acnes infection in their lungs. Eradication of P. acnes by antibiotics prevents the development of granulomas in this experimental model. Although P. acnes is the most common commensal bacterium in the lungs and lymph nodes, P. acnes-specific antibody detected the bacterium within sarcoid granulomas of these organs. P. acnes can cause latent infection in the lung and lymph node and persist in a cell-wall-deficient form. The dormant form is activated endogenously under certain conditions and proliferates at the site of latent infection. In patients with P. acnes hypersensitivity, granulomatous inflammation is triggered by intracellular proliferation of the bacterium. Proliferating bacteria may escape granulomatous isolation, spreading to other organs. Latent P. acnes infection in systemic organs can be reactivated by another triggering event, leading to systemic sarcoidosis.

Extrapulmonary manifestations of sarcoidosis

Sarcoidosis is a systemic disease characterized by the development of epithelioid granulomas in various organs. Although the lungs are involved in most patients with sarcoidosis, virtually any organ can be affected. Recognition of extrapulmonary sarcoidosis requires awareness of the organs most commonly affected, such as the skin and the eyes, and vigilance for the most dangerous manifestations, such as cardiac and neurologic involvement. In this article, the common extrapulmonary manifestations of sarcoidosis are reviewed and organ-specific therapeutic considerations are discussed.

A review of the mechanism of injury and treatment approaches for illness resulting from exposure to water-damaged buildings, mold, and mycotoxins

Physicians are increasingly being asked to diagnose and treat people made ill by exposure to water-damaged environments, mold, and mycotoxins. In addition to avoidance of further exposure to these environments and to items contaminated by these environments, a number of approaches have been used to help persons affected by exposure to restore their health. Illness results from a combination of factors present in water-damaged indoor environments including, mold spores and hyphal fragments, mycotoxins, bacteria, bacterial endotoxins, and cell wall components as well as other factors. Mechanisms of illness include inflammation, oxidative stress, toxicity, infection, allergy, and irritant effects of exposure. This paper reviews the scientific literature as it relates to commonly used treatments such as glutathione, antioxidants, antifungals, and sequestering agents such as Cholestyramine, charcoal, clay and chlorella, antioxidants, probiotics, and induced sweating.

Shortfalls in imputing sarcoidosis to occupational exposures

The cause of sarcoidosis remains elusive. Reports of elevated sarcoidosis incidence in New York City firefighters and World Trade Center disaster responders have been advanced to support a causal relationship. This inference is open to question due to methodological differences in assessing and computing sarcoidosis incidence in populations versus putative occupational exposures. The magnitude of the odds ratio (OR; ca. 1.5) of causal candidates in the ACCESS case-control study of occupational and environmental exposures is sufficiently small that it might easily be attributable to confounders. Additionally, multiplicity of comparisons, difficulty in assembling a valid control population and the potential for recall bias critically limit causal inferences. A possible explanation for etiological elusiveness and multiplicity of elevated OR is that individuals with sarcoidosis, lacking components of efficient cellular immunity, respond with systemic granulomas to a variety of ubiquitous, frequently unidentifiable environmental antigens. Epidemiological methods for the identification of sarcoidosis causal candidates are potentially misleading and are unlikely to prove useful.