Immunology of sarcoidosis

Immune mechanisms of granuloma formation in sarcoidosis and tuberculosis

Sarcoidosis is a complex immune-mediated disease characterized by clusters of immune cells called granulomas. Despite major steps in understanding the cause of this disease, many questions remain. In this Review, we perform a mechanistic interrogation of the immune activities that contribute to granuloma formation in sarcoidosis and compare these processes with its closest mimic, tuberculosis, highlighting shared and divergent immune activities. We examine how Mycobacterium tuberculosis is sensed by the immune system; how the granuloma is initiated, formed, and perpetuated in tuberculosis compared with sarcoidosis; and the role of major innate and adaptive immune cells in shaping these processes. Finally, we draw these findings together around several recent high-resolution studies of the granuloma in situ that utilized the latest advances in single-cell technology combined with spatial methods to analyze plausible disease mechanisms. We conclude with an overall view of granuloma formation in sarcoidosis.

Increased circulating interleukin-23 level in patients with sarcoidosis

BACKGROUND

Sarcoidosis is a Th1-mediated chronic inflammatory disease characterized by non-caseating granulomas. Its pathogenesis is not yet clear, but the possible role of various proinflammatory cytokines is being discussed.

AIM

This study aims to determine serum cytokine (IL-6, IL-12, IL-17, and IL-23) levels in patients with sarcoidosis, and to determine a possible correlation with clinical and laboratory findings of the disease.

MATERIAL AND METHOD

Forty-four biopsy-proven sarcoidosis patients followed up at a single centre and 41 healthy volunteers were included in the study. Demographic, clinical, laboratory, and radiological data of all patients were recorded. Serum samples from the patients and the control group were taken and IL-6, IL-12, IL-17, IL-23 were measured by ELISA method.

RESULTS

Of the 44 sarcoidosis patients, 13(29.5%) were male and 31(70.5%) were female. Average patient age was 47.4 years, mean disease duration was 3.2 years. Twenty-one (47.7%) patients had erythema nodosum, three (6.8%) had uveitis, 40(90.9%) had arthralgia, 23(52.3%) had ankle arthritis, 15(34.1%) had enthesitis. Laboratory evaluation showed increased serum ACE levels in 24(54.5%) patients, increased serum calcium levels in 11 (25%) patients, increased serum D3 levels in 5(11.4%) patients, increased ESR and CRP levels in 22(50%) and 23(52.3%) patients, respectively. Compared with the control group higher serum IL-23 levels were found in the patients with sarcoidosis (p=.01). Serum IL-23 was associated with ankle arthritis (p=.02). Serum IL-6, IL-12, and IL-17 levels were similar in the sarcoidosis patients and the control group (p=.128, p=.212, p=.521 respectively).

CONCLUSION

In our study, we found increased serum IL-23 in patients with sarcoidosis, while serum IL-6, IL-12, and IL-17 were detected as normal. Although our results are somewhat contradictory to other studies in the literature, the question should still be whether sarcoidosis is a Th1/Th17 disease. Multicentre studies are needed in this regard.

Autoantibodies against cytoskeletons and lysosomal trafficking discriminate sarcoidosis from healthy controls, tuberculosis and lung cancers

Sarcoidosis is a systemic granulomatous disease of unknown etiology. Hypergammaglobulinemia and the presence of autoantibodies in sarcoidosis suggest active humoral immunity to unknown antigen(s). We developed a complex cDNA library derived from tissues of sarcoidosis patients. Using a high throughput method, we constructed a microarray platform from this cDNA library containing large numbers of sarcoidosis clones. After selective biopanning, 1070 sarcoidosis-specifc clones were arrayed and immunoscreend with 152 sera from patients with sarcoidosis and other pulmonary diseases. To identify the sarcoidosis classifiers two statistical approaches were conducted: First, we identified significant biomarkers between sarcoidosis and healthy controls, and second identified markers comparing sarcoidosis to all other groups. At the threshold of an False Discovery Rate (FDR) < 0.01, we identified 14 clones in the first approach and 12 clones in the second approach discriminating sarcoidosis from other groups. We used the classifiers to build a naïve Bayes model on the training-set and validated it on an independent test-set. The first approach yielded an AUC of 0.947 using 14 significant clones with a sensitivity of 0.93 and specificity of 0.88, whereas the AUC of the second option was 0.92 with a sensitivity of 0.96 and specificity of 0.83. These results suggest robust classifier performance. Furthermore, we characterized the informative phage clones by sequencing and homology searches. Large numbers of classifier-clones were peptides involved in cellular trafficking and cytoskeletons. These results show that sarcoidosis is associated with a specific pattern of immunoreactivity that can discriminate it from other diseases.

Serum galectin-3 and TGF-beta levels in patients with sarcoidosis

INTRODUCTION

Sarcoidosis is a chronic granulomatous disease that develops with non-caseified granuloma formation. Galectin-3 is a multifunctional protein operating in biological processes such as fibrosis, angiogenesis, and immune activation.

PURPOSE

This study evaluates the levels of serum galectin-3 and TGF-beta in sarcoidosis patients to determine a possible correlation with clinical findings.

MATERIAL AND METHOD

Forty-four biopsy-proven sarcoidosis patients followed in a single centre and 41 age and sex-matched healthy volunteers were included in the study. The levels of serum galectin-3 and TGF-beta were evaluated by ELISA method.

RESULTS

Among the 44 sarcoidosis patients, 13(29.5%) were male and 31(70.5%) were female. The average patient age was 47.4 and the average disease duration was 3.2 years. The level of serum galectin-3 was found to be the same as in the control group and had no significance statistically (p=.977). No correlation was determined between the level of serum galectin-3 and clinical and laboratory findings of sarcoidosis (p>.05). The level of serum TGF-beta was found to be higher in the sarcoidosis patients when compared to that of the control group (p=.005). While a correlation was found between serum TGF-beta and enthesitis, sacroiliitis, and arthralgia (p=.006, p=.034, p=.02), no correlation was determined on the other clinical and laboratory findings (p>.05).

CONCLUSION

While the level of serum galectin-3 was determined to be normal in sarcoidosis patients, a high level of serum TGF-beta was found. These findings show that TGF-beta may play an important role in sarcoidosis pathogenesis and the formation of granuloma.

Association between neurosarcoidosis with autonomic dysfunction and anti-ganglionic acetylcholine receptor antibodies

OBJECTIVE

To determine whether autonomic dysfunction in neurosarcoidosis is associated with anti-ganglionic acetylcholine receptor (gAChR) antibodies, which are detected in autoimmune autonomic ganglionopathy.

METHODS

We retrospectively extracted cases of sarcoidosis from 1787 serum samples of 1,381 patients between 2012 and 2018. Anti-gAChR antibodies against the α3 and β4 subunit were measured by luciferase immunoprecipitation to confirm the clinical features of each case. We summarized literature reviews of neurosarcoidosis with severe dysautonomia to identify relevant clinical features and outcomes.

RESULTS

We extracted three new cases of neurosarcoidosis with severe dysautonomia, among which two were positive for anti-gAChR antibodies: Case 1 was positive for antibodies against the β4 subunit, and Case 2 was positive for antibodies against both the α3 and β4 subunits. We reviewed the cases of 15 patients with neurosarcoidosis and severe dysautonomia, including the three cases presented herein. Orthostatic hypotension and orthostatic intolerance were the most common symptoms. Among the various types of neuropathy, small fiber neuropathy (SFN) was the most prevalent, with seven of nine cases exhibiting definite SFN. Six of eight cases had impaired postganglionic fibers, of which the present three cases revealed abnormality of 123I-MIBG myocardial scintigraphy. Of the 11 cases, 10 were responsive to immunotherapy, except one seropositive case (Case 2).

CONCLUSIONS

The presence of gAChR antibodies may constitute one of the mechanisms by which dysautonomia arises in neurosarcoidosis.

Serum Galectin-3 and TGF-Beta Levels in Patients With Sarcoidosis

INTRODUCTION

Sarcoidosis is a chronic granulomatous disease that develops with non-caseified granuloma formation. Galectin-3 is a multifunctional protein operating in biological processes such as fibrosis, angiogenesis, and immune activation.

PURPOSE

This study evaluates the levels of serum galectin-3 and TGF-beta in sarcoidosis patients to determine a possible correlation with clinical findings.

MATERIAL AND METHOD

Forty-four biopsy-proven sarcoidosis patients followed in a single centre and 41 age and sex-matched healthy volunteers were included in the study. The levels of serum galectin-3 and TGF-beta were evaluated by ELISA method.

RESULTS

Among the 44 sarcoidosis patients, 13(29.5%) were male and 31(70.5%) were female. The average patient age was 47.4 and the average disease duration was 3.2 years. The level of serum galectin-3 was found to be the same as in the control group and had no significance statistically (p=.977). No correlation was determined between the level of serum galectin-3 and clinical and laboratory findings of sarcoidosis (p>.05). The level of serum TGF-beta was found to be higher in the sarcoidosis patients when compared to that of the control group (p=.005). While a correlation was found between serum TGF-beta and enthesitis, sacroiliitis, and arthralgia (p=.006, p=.034, p=.02), no correlation was determined on the other clinical and laboratory findings (p>.05).

CONCLUSION

While the level of serum galectin-3 was determined to be normal in sarcoidosis patients, a high level of serum TGF-beta was found. These findings show that TGF-beta may play an important role in sarcoidosis pathogenesis and the formation of granuloma.

Biodistribution and Radiation Dosimetry of 124I-DPA-713, a PET Radiotracer for Macrophage-Associated Inflammation

Whole-body PET/CT was performed using 124I-DPA-713, a radioligand for the 18-kDa translocator protein (TSPO), to determine biodistribution and radiation dosimetry. Methods: Healthy subjects aged 18-65 y underwent whole-body PET/CT either at 4, 24, and 48 h or at 24, 48, and 72 h after intravenous injection of 124I-DPA-713. Time-activity curves were generated and used to calculate organ time-integrated activity coefficients for each subject. The resulting time-integrated activity coefficients provided input data for calculation of organ absorbed doses and effective dose for each subject using OLINDA. Subjects were genotyped for the TSPO polymorphism rs6971, and plasma protein binding of 124I-DPA-713 was measured. Results: Three male and 3 female adults with a mean age of 40 ± 19 y were imaged. The mean administered activity and mass were 70.5 ± 5.1 MBq (range, 62.4-78.1 MBq) and 469 ± 34 ng (range, 416-520 ng), respectively. There were no adverse or clinically detectable pharmacologic effects in any of the 6 subjects. No changes in vital signs, laboratory values, or electrocardiograms were observed. 124I-DPA-713 cleared rapidly (4 h after injection) from the lungs, with hepatic elimination and localization to the gastrointestinal tract. The mean effective dose over the 6 subjects was 0.459 ± 0.127 mSv/MBq, with the liver being the dose-limiting organ (0.924 ± 0.501 mGy/MBq). The percentage of free radiotracer in blood was approximately 30% at 30 and 60 min after injection. Conclusion:124I-DPA-713 clears rapidly from the lungs, with predominantly hepatic elimination, and is safe and well tolerated in healthy adults.

Role of serum immunoglobulins for predicting sarcoidosis outcome: A cohort study

Background

Sarcoidosis is a systemic granulomatous disease which carries variable outcomes. Serum protein electrophoresis is an easily accessible and routinely performed examination at diagnosis, in order to search for hypergammaglobulinemia, which is frequently found, and to rule out other granulomatous diseases such as common variable immunodeficiency. We aimed to assess the impact of baseline immunoglobulin level on the outcome of sarcoidosis.

Methods

We conducted a retrospective cohort-study, at Rennes University Hospital, in which all newly diagnosed patients for whom a serum protein electrophoresis had been performed at baseline were enrolled, from 2006 to 2014. The main outcome was the need for corticosteroid treatment within 2 years from diagnosis, the secondary outcome was the occurrence of relapse among treated patients.

Results

Eighty patients were included in the study, and 41.25% of them exhibited an elevated globulins rate. In univariate analysis, an elevated ACE level >70 U/l, Afro-Caribbean origin, and extra-pulmonary involvement, were associated with the need for corticosteroid treatment. In multivariate analysis, only ACE elevation (OR = 1.03, IC95% 1.01–1.05, p = 0.009) and extra-pulmonary involvement (OR = 5.8, IC95% 1.4–24, p = 0.015) were significant. Immunoglobulin level was not associated with the main outcome. Regarding the secondary outcome, none of the studied features were predictive of relapse among the 34 treated patients followed for two years.

Conclusions

There was no relation between the immunoglobulin level at diagnosis and the evolution of sarcoidosis. An elevated ACE level and the presence of initial extra-pulmonary involvement were both associated with a more severe course of the disease necessitating a corticosteroid treatment.

Plasmacytoid dendritic cells in cutaneous sarcoidosis

While absent from normal skin, plasmacytoid dendritic cells (pDCs) infiltrate the skin in several infectious, inflammatory, and neoplastic entities. In addition to providing anti-viral resistance, pDCs link the innate and adaptive immune responses. Sarcoidosis is an idiopathic multi-system granulomatous disease characterized by epitheliod granulomas. Its underlying immunopathogenesis involves hyperactivity of cell-mediated immune system with involvement of CD4+ T-helper cells of the Th1 subtype. Recently, pDCs have been shown to contribute to other cutaneous granulomatous disorders such as granuloma annulare (GA). Here, we intend to investigate pDC occurrence and activity in cutaneous sarcoidosis. Twenty cutaneous sarcoidosis cases and a comparable group of 20 cases of GA were retrieved from our database and were immunohistochemically tested for pDC occurrence and activity using anti-BDCA-2 and anti-MxA antibodies, respectively. Fifteen cases of cutaneous lupus erythrematosus (LE) were used as a comparison group. A semi-quantitative scoring system was used. pDCs were present in all cutaneous sarcoidosis in peri-vascular and/or peri-adnexal location admixed with lymphocytes. pDC numbers in sarcoidosis were comparable to those in GA, while pDCs were significantly more abundant in LE. MxA expression was mostly patchy in cutaneous sarcoidosis and GA cases, while LE cases showed diffuse and strong MxA expression. In conclusion, we have shown that pDCs are recruited into the skin lesions of sarcoidosis and GA. Despite the diminished type I IFN production demonstrated in our study, the consistent presence of pDCs in all cutaneous sarcoidosis cases speaks in favor of some role of these cells in the pathogenesis of granulomatous disorders. (Sarcoidosis Vasc Diffuse Lung Dis 2018; 35: 55-61).

Coexistence of sarcoidosis and Familial Mediterranean Fever

Sarcoidosis is a chronic inflammatory disease with unknown cause characterized by non-caseating granuloma formations. It may present with bilateral hilar lymphadenopathy, skin lesions, the involvement of eye and symptoms on the locomotor system. FMF (Familial Mediterranean Fever) is an autosomal recessive autoinflammatory disease, characterized by recurrent episodes of fever and polyserositis. Simultaneous occurrence of these diseases is rare. In this paper, we reported the coexistence of sarcoidosis with FMF.

[Sarcoidosis and uveitis : An update]

Ocular involvement in sarcoidosis is present in up to one third of patients and is frequently manifested before the underlying systemic disease has been diagnosed. With a view to the therapeutic consequences an early diagnosis of the underlying disease is advantageous. In cases of visual loss early diagnostic measures include invasive procedures, such as ultrasound-guided bronchoalveolar lavage and transbronchial biopsy, if nodular conjunctival or cutaneous manifestations which would confirm the diagnosis are not present. Sufficiently sensitive biomarkers of disease activity have not yet been identified. As elevated activity of angiotensin-converting enzyme (ACE) and lysozyme are associated with disease activity they may be supportive of but not specific for the diagnosis. Other indicators include calcemia, calciuria, augmented activity of hepatic enzymes, cutaneous anergy and hilar changes in the lungs. In patients with newly diagnosed anterior uveitis presenting with granulomatous mutton-fat corneal precipitates, snow balls and vitreous body base condensates with mild retinal periphlebitis in intermediate uveitis as well as multifocal choroiditis (creamy choroidal lesions at different stages of activity and approximately 500 µm in diameter), a diagnosis of sarcoidosis has to be considered and tuberculosis should be excluded, even in the absence of a known systemic disease. Anterior uveitis is frequently a self-limiting condition, which can be well-controlled with topical steroids. On the other hand, intermediate, posterior and panuveitis are typically associated with a chronic course and require systemic therapy to prevent severe loss of vision. If the response to systemic corticosteroids is insufficient, treatment with immunomodulatory agents and biologics is initiated at progressively earlier stages, with a view to averting permanent organ damage and frequently with a positive impact on the short and long-term outcomes, even in therapy-refractive cases.

The clinical characteristics of sarcoid arthropathy based on a prospective cohort study

BACKGROUND

Sarcoidosis is known as a Th1-mediated disease, which can mimic many primary rheumatologic diseases or sometimes co-exist with them. Clinical characteristics of sarcoid arthropathy are not well described and the studies reported in the literature so far are mostly based on data from referrals. The aim of this study was to evaluate the incidence and clinical characteristics of sarcoid arthropathy.

METHODS

All our patients were prospectively evaluated in our rheumatology outpatient center from 2011 to 2015. A total of 114 (32 male) patients with sarcoidosis who were admitted to our clinic were included in the study. Clinical, demographical, laboratory, radiological and histological data of these patients obtained during 4-year follow-up and treatment period were compiled and analyzed.

RESULTS

The mean patient age was 48.1 years (range, 20-82 years), and the mean disease duration was 40.5 months (range, 1-300 months). Sarcoid arthritis was observed in 71 (62.3%), and arthralgia in 106 (92.9%) patients. Out of the 71 patients with arthritis, 61 (85.9%) had involvement of ankle, 7 (9.8%) knee, 2 (2.8%) wrist, MCP and PIP joints, and 1 (1.4%) had shoulder periarthritis. Oligoarthritis (two to four joints) was the most common pattern followed by monoarthritis and polyarthritis. Arthritis and erytjhema nodosum and arthritis and female sex was found to be correlated (p = 0.03 and p = 0.001). Again, in patients with arthritis, even higher levels of CRP/ESR as well as ANA and RF positivity were observed (p = 0.03, p = 0.01, p = 0.01, and p = 0.02, respectively). A total of 11 patients had another rheumatic pathology concurrent with sarcoidosis.

CONCLUSIONS

Inflammatory arthritis occurs in a majority of patients with sarcoidosis. Acute arthritis with bilateral ankle involvement is the most common pattern of sarcoid arthropathy. Sarcoidosis can mimic many primary rheumatic diseases or may coexist with them. Sarcoidosis should be considered not only as a mimicker but also as a Th1-mediated primary rheumatologic pathology.

Co-occurrence of rheumatoid arthritis and sarcoidosis

Rheumatoid arthritis (RA) is a chronic inflammatory disease characterised by erosive arthritis. Sarcoidosis is a chronic disease characterised by formation of non-calcified granulomas. Our case, a 35-year-old woman, presented with metacarpophalangeal, proximal interphalangeal (PİP) joints and arthritis of both ankles, of 6-month duration. She had morning stiffness lasting 1 h, restriction of range of motion and erythaema nodosum. Laboratory tests showed elevated acute phase responses and serum ACE levels, and anti-cyclic citrullinated peptide antibody positivity. There was periarticular osteoporosis on her hand and wrist on direct X-rays and hilar lymphadenopathy on her thorax CT. The pathological result of endobronchial ultrasound biopsy showed non-calcified granuloma congruent with sarcoidosis. According to clinical, laboratory and histopathological evaluation, the patient was diagnosed with RA and sarcoidosis. Corticosteroids and methotrexate were started, and on her sixth month of follow-up, her clinical and laboratory findings and lymphadenopathies on CT had regressed. The clinical follow-up continues; the patient appears to be in clinical remission.

Granulomatous dysimmune reactions (sarcoidosis, granuloma annulare, and others) on differently injured skin areas

Granulomatous disorders are chronic cell-mediated immune responses histologically characterized by collections of macrophages, epithelioid cells, and multinucleated giant cells. This disease spectrum often has an infectious origin, but sometimes neither an infective agent nor an inciting antigenic stimulus can be identified. The skin may be a preferential target for these disorders, especially in the areas that have been damaged by various forms of skin injury (eg, herpetic infections, trauma, thermal or solar burns, vaccinations, tattoos). These damaged skin sites frame the new concept of an immunocompromised cutaneous district (ICD), which defines a skin area with acquired immune dysregulation that can pave the way for the local onset of opportunistic disorders, such as infections, tumors, and granulomatous disorders. Sarcoidosis, granuloma annulare (GA), and forms of granulomatous vasculitis, such as Churg-Strauss syndrome (CSS) and Wegener's granulomatosis (WG), are the most common granulomatous disorders that occur in an ICD and may share common pathogenic mechanisms. Recent studies have found clinical and pathologic overlapping features across noninfectious granulomas. Although no unifying etiology exists, the development of granulomatous processes in the ICD has often been reported and the literature contains various hypotheses to explain it: (1) overactive immune response in a previously injured region with or without loss of immune tolerance; (2) overall reduced immune response; (3) retention of an exogeneous antigen or foreign body; (4) altered neural signaling; and (5) a combination of all the aforementioned processes. T helper cells, T regulatory cells, and macrophages, as well as a number of antigenic proteins, have been identified as potential contributing factors. In addition, a genetic predisposition and an intact systemic immune system are both instrumental for the persistence of local granuloma formation in the ICD.

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.

Advances in the diagnosis and treatment of sarcoidosis

This manuscript outlines recent advances in the diagnosis and treatment of sarcoidosis. The diagnosis of sarcoidosis can occasionally be made on clinical grounds without a confirmatory biopsy when very specific clinical findings are present. Otherwise, the diagnosis requires histologic evidence of granulomatous inflammation, exclusion of alternative causes, and evidence of systemic disease. Because there is no available diagnostic test for sarcoidosis, the diagnosis is never completely secure. Instruments have been developed to establish the presence of sarcoidosis in a second organ and hence establish the systemic nature of the disease. Corticosteroids remain the drug of choice for the treatment of sarcoidosis. Additional sarcoidosis medications are most commonly used as corticosteroid-sparing agents. Recent clinical sarcoidosis drug trials have exposed important issues that may confound trial results, including selecting patients with active disease, identifying study drug effects in patients receiving concomitant corticosteroids, and establishing proper study endpoints.

Coexistence of Ankylosing Spondylitis and Löfgren's Syndrome

A 46-year-old male patient diagnosed with ankylosing spondylitis presented to our polyclinic with complaints of pain, swelling, and limitation in joint mobility in both ankles and erythema nodosum skin lesions in both pretibial sites. The sacroiliac joint graphy and the MRI taken revealed active and chronic sacroiliitis. On the thorax CT, multiple mediastinal and hilar lymphadenopathies were reported. Mediastinoscopic excisional lymph node biopsy was taken and noncalcified granulomatous structures, lymphocytes, and histiocytes were determined on histopathological examination. The patients were diagnosed with ankylosing spondylitis, sarcoidosis, and Löfgren's syndrome. NSAIDs, sulfasalazine, and low dose corticosteroid were started. Significant regression was seen in the patient's subjective and laboratory assessments.

Sarcoidois: is it only a mimicker of primary rheumatic disease? A single center experience

BACKGROUND

Sarcoidosis is known as a T helper 1 lymphocyte (Th1-Ly) mediated disease which can imitate or sometimes accompany many primary rheumatic diseases. The purpose of this study is to share the clinical, demographic and laboratory data of patients presenting with rheumatologic manifestations and diagnosed with sarcoidosis.

METHODS

A total of 42 patients (10 men) were included in the study. The patients were admitted to the rheumatology outpatient clinic for the first time with different rheumatic complaints between November 2011 and May 2013 and were diagnosed with sarcoidosis after relevant tests. Clinical, demographic, laboratory, radiological and histological data of these patients were collected during the 18-month follow-up period and then analyzed.

RESULTS

Mean patient age was 45.2 years (20-70 years) and mean duration of disease was 3.5 years (1 month-25 years). Evaluation of system and organ involvement revealed that 20 (47.6%) patients had erythema nodosum, 3 (7.1%) had uveitis, 1 (2.3%) had myositis, 1 (2.3%) had neurosarcoidosis, 32 (76.2%) had arthritis and 40 (95.2%) had arthralgia. Of the 32 patients with arthritis, 28 (87.5%) had involvement of the ankle, 3 (9.4%) had involvement of the knee and 1 (3.2%) had involvement of the wrist. No patient had cardiac involvement. Thoracic computed tomography scan showed stage 1, 2, 3 and 4 sarcoidosis in 12 (28.5%), 22 (52.4%), 4 (9.5%) and 4 (9.5%) patients, respectively. Histopathology of sarcoidosis was verified by endobronchial ultrasound, mediastinoscopy and skin and axillary biopsy of lymphadenopathies, which revealed noncaseating granulomas. Laboratory tests showed elevated serum angiotensin-converting enzyme in 15 (35.7%) patients, elevated serum calcium level in 6 (14.2%) patients and elevated serum 1,25-dihydroxyvitamin D concentrations in 2 (4.7%) patients. Serological tests showed antinuclear antibody positivity in 12 (28.5%) patients, rheumatoid factor positivity in 7 (16.6%) patients and anticyclic citrullinated antibody positivity in 2 (4.8%) patients.

CONCLUSION

Sarcoidosis can imitate or accompany many primary rheumatic diseases. Sarcoidosis should be considered not simply as an imitator but as a primary rheumatic pathology mediated by Th1-Ly. New studies are warranted on this subject.

Coexistence of sarcoidosis and systemic sclerosis

Sarcoidosis is a multisystem granulomatous disease characterized by hilar lymphadenopathy, involvement of internal organs, and diverse skin lesions. Systemic sclerosis is an autoimmune disease characterized by skin hardening and different internal organ fibrosis, including vascular abnormality. Immune response associated with Th-2 has been shown in the early and active stage of the disease. In this paper, we report coexistence of systemic sclerosis with sarcoidosis in a female patient presenting with granulomatous dermatitis, interstitial lung disease, and Raynaud's phenomenon complaints.

Interferon-β-induced pulmonary sarcoidosis in a 30-year-old woman treated for multiple sclerosis: a case report

Introduction

With the increasing use of recombinant α and β interferon therapy for the treatment of various disorders, cases of interferon-associated sarcoidosis have been reported in the literature. The majority of these have been cases of interferon-α-induced sarcoidosis. We present the first case, to the best of our knowledge, of interferon-induced pulmonary sarcoidosis in a patient whose multiple sclerosis was treated with interferon-β.

Case presentation

We present the case of a 30-year-old Caucasian woman who presented with unusually persistent bilateral areas of lung consolidation on serial radiographs. Pulmonary sarcoidosis was diagnosed on transbronchial lung biopsy five months after the initiation of treatment with interferon-β for multiple sclerosis.

Conclusions

Sarcoidosis should be considered in the differential diagnosis of a patient who develops clinical or radiological pulmonary disease while undergoing interferon therapy. It is important to note that interferon-induced sarcoidosis, though usually seen in cases with interferon-α, can occur with interferon-β. Neurologists managing patients with multiple sclerosis should be aware of this association between interferon-β and sarcoidosis and promptly refer patients developing respiratory symptoms for further investigation.

Serratia pneumonia presenting as hemoptysis in a patient with sarcoidosis: a case report

Introduction

Serratia marcescens is a Gram-negative bacillus which belongs to the family Enterobacteriaceae. It is a facultative anaerobe and produces red pigment at room temperature. It naturally occurs in soil and water as well as the intestines, and it is responsible for nosocomial infections. There have been few reports about community acquired pneumonia of Serratia.

Case presentation

This report presents a 37-year-old man with hemoptysis, fever, and shortness of breath. The clinical and laboratory examinations revealed that the patient had pseudohemoptysis due to S. marcescens pneumonia, on an immunocompromised pattern, because of the coexistence of sarcoidosis (stage 1).

Conclusion

Appropriate antibiotic therapy for Serratia was administered, and the patient’s symptoms regressed. The patient is healthy and asymptomatic after 1-year follow-up. To the best of the authors’ knowledge, this is the first reported case of a pseudohemoptysis in a patient with pulmonary sarcoidosis.

Diagnostic and therapeutic challenges of hepatic sarcoidosis

The authors report three cases of hepatic sarcoidosis complicated by portal hypertension in Caucasian patients. The cases varied in their presentations from normal liver function to symptomatic cholestasis and established liver cirrhosis. In one particular case the authors discovered hepatic sarcoid after a diagnostic gastroscopy for upper gastrointestinal (GI) bleeding which showed changes of portal hypertension. In all of these cases the authors gave our patients a prolonged course of immunosuppressive treatment with over all good long-term results. The authors hope that our work will provide a modern approach into treating this disease.

Adaptive immune responses in primary cutaneous sarcoidosis

Sarcoidosis is a multisystemic inflammatory disorder with cutaneous lesions present in about one-quarter of the patients. Cutaneous lesions have been classified as specific and nonspecific, depending on the presence of nonnecrotizing epithelial cell granulomas on histologic studies. The development and progression of specific cutaneous sarcoidosis involves a complex interaction between cells of the adaptive immune systems, notably T-lymphocytes and dendritic cells. In this paper, we will discuss the role of T-cells and skin dendritic cells in the development of primary cutaneous sarcoidosis and comment on the potential antigenic stimuli that may account for the development of the immunological response. We will further explore the contributions of selected cytokines to the immunopathological process. The knowledge of the adaptive immunological mechanisms operative in cutaneous sarcoidosis may subsequently be useful for identifying prevention and treatment strategies of systemic sarcoidosis.

Sarcoidosis: clinical presentation, diagnosis, and approach to treatment

Sarcoidosis is an idiopathic granulomatous disease. It usually affects the lung but may involve any organ. The diagnosis may be problematic because known causes of granulomatous inflammation must be excluded. Sarcoidosis may remit spontaneously or remain stable. Therefore, therapy is not mandated for the disease. This report reviews the clinical presentation, diagnostic approach, and treatment of sarcoidosis.

Butyrophilin-like 2 gene is associated with ulcerative colitis in the Japanese under strong linkage disequilibrium with HLA-DRB1*1502

The human leukocyte antigen (HLA) region has been implicated in the pathogenesis of inflammatory bowel disease (IBD), which is classified into Crohn's disease (CD) and ulcerative colitis (UC). Recently, an association between sarcoidosis and the butyrophilin-like 2 (BTNL2) gene was reported. BTNL2 is located in the HLA region and its messenger RNA is expressed most abundantly in the intestine. In this study, we performed a case-control association study of BTNL2 in the Japanese patients with IBD and performed linkage disequilibrium (LD) analysis between BTNL2 and HLA-DRB1. We analyzed eight polymorphisms selected after direct sequencing and found that none of the polymorphisms were associated with the Japanese CD cohort. In contrast, five polymorphisms were significantly associated with UC, especially three single nucleotide polymorphisms (BTNL2_19, BTNL2_22 and BTNL2_23) were associated as a haplotype. The most frequent haplotype (GGC haplotype) was a low-risk haplotype (P= 0.000052), whereas the other TCT haplotype was a high-risk haplotype (P= 0.0000085). Among the eight polymorphisms, the strongest association with UC was found in BTNL2_19 (OR = 1.92, P= 0.0000035). As expected, the BTNL2_19-T allele showed strong LD with DRB1*1502 (D'= 0.92). When BTNL2_19 was tested as conditional on the DRB1*1502 carrier status, the significant association disappeared, suggesting that the association was because of its strong LD with DRB1*1502. We conclude that BTNL2 does not contribute to the susceptibility to Japanese CD but is associated with Japanese UC because of the strong LD with HLA-DRB1*1502. The strong LD between BTNL2 and HLA-DRB1 raises another issue about the potential role of BTNL2 in other diseases associated with HLA-DRB1.

Immunopathogenesis of sarcoidosis

The immunopathogenesis of sarcoidosis has been difficult to charaterize given the heterogeneity of disease, the elusiveness of the causative antigen, and the lack of an adequate animal model. However, by examining well-defined clinical cohorts, the interplay between genetic predisposition and immunologic response has been increasingly informative. Technological advances in cellular analysis have allowed researchers to characterize the immune responses important in the maintenance of granulomatous inflammation. Finally, "new" clinical observations such as granuloma responsiveness to targeted biological therapies, sarcoid developing during immune restoration, and the relationship between sarcoidosis and Hepatitis C will provide future insight to the immunopathogenesis of sarcoidosis.

Pulmonary immune responses to Propionibacterium acnes in C57BL/6 and BALB/c mice

Propionibacterium acnes (PA) is a gram-positive anaerobic bacterium implicated as a putative etiologic agent of sarcoidosis. To characterize the pulmonary immune response to PA, C57BL/6 and BALB/c mice were intraperitoneally sensitized and intratracheally challenged with heat-killed bacteria. C57BL/6 mice challenged with PA developed a cellular immune response characterized by elevations in Th1 cytokines/chemokines, increased numbers of lymphocytes and macrophages in lung lavage fluid, and peribronchovascular granulomatous inflammation composed of T- and B-lymphocytes and epithelioid histiocytes. T-lymphocytes in the lung lavage fluid showed a marked CD4+ cell predominance. In contrast, C57BL/6 mice challenged with Staphylococcus epidermidis (SE), another gram-positive commensal of human skin, and BALB/c mice challenged with PA, showed only a modest induction of Th1 cytokines, less pulmonary inflammation, and no granulomatous changes in the lung. Enhancement of Toll-like receptor expression was seen in PA-exposed C57BL/6 mice within 24 h after exposure, suggesting that induction of innate immunity by PA contributes to the robust, polarized Th1 immune response elicited by this bacterium. These findings suggest that PA-induced pulmonary inflammation may be a useful model for testing the contributions of both bacterial and host factors in the development, maintenance, and resolution of granulomatous inflammation in the lung.

Eight fundamental unsolved problems in sarcoidosis

More than 100 years since the identification and characterization of sarcoidosis, its etiology, fundamental nature, pathogenesis, incidence, ethnic predilections, relationship to the Kveim test and prognostic determinants remain largely either unknown or unexplained, and treatment indications, absent compelling findings, remain undefined. Professor Hilbert's "Address" delineates these fundamental deficits in our knowledge and understanding.

High expression of p21 Waf1 in sarcoid granulomas: a putative role for long-lasting inflammation

In sarcoid granulomas, apoptotic events are reduced, which explains their characteristic long-lasting inflammation. We have described that interferon-gamma (IFN-gamma) inhibits apoptosis in macrophages through the expression of p21(Waf1). Here, we explore the molecular mechanisms involved in the inhibition of apoptosis in sarcoid granulomas. We analyzed skin biopsies from 19 sarcoidosis patients and 16 controls. Total RNA was subjected to semiquantitative reverse transcriptase-polymerase chain reaction analysis. There was no difference found in the expression of proapoptotic (Bax and Bcl-X(s)) or antiapoptotic (Bcl-2 and Bcl-X(L)) genes nor in the expression of the tumor suppressor gene p53. Furthermore, the expression of IFN-gamma and the cdk inhibitors p21(Waf1) and p27(Kip1) were analyzed. IFN-gamma was detected in 37% of the sarcoidosis patients, and controls were negative (P<0.02). In addition, a higher proportion of patients expressing p21(Waf1) (58%) versus controls (12%) was found (P<0.005). There was a significant correlation between the expression of IFN-gamma and p21(Waf1) (r=0.69) and between p21(Waf1) and fibronectin (r=0.65). Finally, using immunohistochemistry, high p21(Waf1) reactivity was observed inside the granuloma. We conclude that the high levels of p21(Waf1) in sarcoidosis may explain the absence of apoptosis in the granuloma and the persistence of inflammation.

Etanercept for the treatment of stage II and III progressive pulmonary sarcoidosis

BACKGROUND

Tumor necrosis factor (TNF)-alpha is produced by macrophages and other cells, and is believed to participate in granulomatous inflammation. Targeted antagonism of TNF-alpha has been proposed as a novel treatment strategy for sarcoidosis. Etanercept is a dimeric fusion protein that binds specifically to TNF-alpha, rendering it biologically inactive.

OBJECTIVE

To assess whether etanercept has potential efficacy in the treatment of progressive pulmonary sarcoidosis.

DESIGN

Prospective, open-label, phase-2 treatment trial.

SETTING

Mayo Clinic, Rochester, MN.

PATIENTS

Stage II or III progressive pulmonary sarcoidosis.

INTERVENTION

Etanercept, 25 mg subcutaneously twice weekly.

MEASUREMENTS

Pulmonary function, chest radiographs, dyspnea, and TNF-alpha levels in serum and BAL fluid.

RESULTS

The study was terminated after the enrollment of 17 patients due to an early-stop clause of the pretrial study design related to excessive treatment failures. Neither absolute levels of TNF-alpha nor TNF-alpha activity in the serum, BAL fluid, or alveolar macrophages were able to predict which patients would respond to etanercept.

CONCLUSIONS

In patients with progressive stage II or III pulmonary sarcoidosis, etanercept was frequently associated with early or late treatment failure. These data would not support the design of a large multicenter randomized trial comparing etanercept with conventional corticosteroid therapy.

Serum soluble interleukin-2 receptor measurement in patients with sarcoidosis: a clinical evaluation

OBJECTIVES

To date, insufficient evidence is available to recommend serum soluble interleukin-2 receptor (sIL-2R) measurement as a routine test in the assessment of sarcoidosis. Therefore, we evaluated the clinical value of this test.

DESIGN

Forty-seven patients with sarcoidosis, all presenting with active disease, were included in the study. Initial serum sIL-2R levels were determined by enzyme-linked immunosorbent assay, and clinical data at presentation and follow-up were collected retrospectively.

RESULTS

The median follow-up period of all patients was 44 months (range, 6 to 100 months), and 38 patients had follow-up data present over at least 24 months. The median sIL-2R level was 1,068 U/mL (range, 248 to 4,410 U/mL; upper limit of normal, 710 U/mL). A positive correlation was found between serum sIL-2R levels and the number of CD4+ T lymphocytes in BAL (rs = 0.53, p < 0.001). In accordance with this result, both sIL-2R level and the number of CD4+ T lymphocytes were elevated in stage I compared to stage III disease (p < 0.05). Patients with extrapulmonary disease (ED) [excluding Löfgren's syndrome] showed higher sIL-2R levels than those presenting with only pulmonary sarcoidosis (p = 0.001). No relation was found between sIL-2R level and response to treatment, and there was no association between sIL-2R levels and radiographic evolution and lung function outcome.

CONCLUSIONS

Our data suggest a role for serum sIL-2R as marker of pulmonary disease activity and ED in patients with sarcoidosis.

Granulomatous pulmonary disease in a child: an unusual presentation of Crohn's disease

Crohn's disease (CD) is a chronic inflammatory disorder of the bowel which may be associated with an extensive list of extraintestinal manifestations involving almost every organ system. The most common organs involved are the eyes, skin, joints, and liver. Symptomatic bronchopulmonary disorders have been reported only rarely in pediatric CD. We report on an 11-year-old child who had a recurrent cough and increasing dyspnea with exercise for 8 months before developing any gastrointestinal symptoms. He was demonstrated to have granulomatous inflammation of the lung, as well as of the gastrointestinal tract. Similarities between CD and sarcoidosis are discussed.