Diagnosis of Sarcoidosis

The Immune Response and the Pathogenesis of Idiopathic Inflammatory Myositis: a Critical Review

The pathogenesis of idiopathic inflammatory myositis (IIMs, including polymyositis and dermatomyositis) remains largely enigmatic, despite advances in the study of the role played by innate immunity, adaptive immunity, genetic predisposition, and environmental factors in an orchestrated response. Several factors are involved in the inflammatory state that characterizes the different forms of IIMs which share features and mechanisms but are clearly different with respect to the involved sites and characteristics of the inflammation. Cellular and non-cellular mechanisms of both the immune and non-immune systems have been identified as key regulators of inflammation in polymyositis/dermatomyositis, particularly at different stages of disease, leading to the fibrotic state that characterizes the end stage. Among these, a special role is played by an interferon signature and complement cascade with different mechanisms in polymyositis and dermatomyositis; these differences can be identified also histologically in muscle biopsies. Numerous cellular components of the adaptive and innate immune response are present in the site of tissue inflammation, and the complexity of idiopathic inflammatory myositis is further supported by the involvement of non-immune mechanisms such as hypoxia and autophagy. The aim of this comprehensive review is to describe the major pathogenic mechanisms involved in the onset of idiopathic inflammatory myositis and to report on the major working hypothesis with therapeutic implications.

Thoracic Sarcoidosis: Imaging with High Resolution Computed Tomography

INTRODUCTION

Sarcoidosis is a disease of unknown aetiology that primarily affects the lungs. Clinical and radiological findings with demonstration of non caseating granulomas on pathology is utilised for diagnosing the disease.

AIM

To assess and evaluate the features of thoracic sarcoidosis on High Resolution Computed Tomography (HRCT) chest.

MATERIALS AND METHODS

A total of 40 (31 males and 9 females) cases of pulmonary sarcoidosis in a period of three years were included in this study. Patients underwent detailed clinical evaluation, imaging, Pulmonary Function Tests (PFT) and pathological confirmation of disease. Chest radiograph was obtained in all patients. HRCT was done on 16 slice Computed Tomography (CT) using 1 mm slice thickness and high spatial frequency algorithm for image re-construction. Images were viewed and evaluated using appropriate lung and mediastinal windows. The lymph nodes were classified as hilar and mediastinal with Maximum Short Axis Diameter (MSAD) more than 10 mm taken as cut-off for enlargement. Pulmonary opacities were classified as nodules (micronodules 1-4 mm and macronodules >5 mm), reticular opacities, fibrotic lesions, ground glass opacities and consolidations. Nodule distribution classified as perilymphatic centrilobular and random. Repeat scanning done on follow up or as clinically indicated.

RESULTS

A total of five patients had Stage I disease, 24 patients had Stage II disease, eight patients had Stage III disease and three patients had stage IV disease. Mediastinal lymphdenopathy present in 29 patients. Bilateral hilar adenopathy was the predominant pattern seen in 22 patients. Lung parenchymal lesions excluding end stage disease noted in 32 patients. The characteristic HRCT lung parenchymal involvement of micronodules with a perilymphatic distribution was seen in 26 patients. HRCT features of predominant upper and middle lobe distribution seen in majority of patients. Documented atypical lesions and the characteristic features of end stage lung disease on HRCT noted in a small subset of patients. HRCT was superior to chest radiography for evaluating the features, pattern and distribution of the parenchymal lesions and mediastinal lymph nodes, for assessing the stage and activity of the disease and in aiding detection of subtle parenchymal lesions which are liable to be missed on conventional imaging.

CONCLUSION

Thoracic sarcoidosis can have varied presentations. HRCT is superior to conventional CT for the detection and characterisation of the lung parenchymal lesions.

Granulomatous & histiocytic dermatitides

Granulomas of the skin may be classified in several ways. They are either infectious or non-infectious in character, and they contain areas of necrobiosis or necrosis, or not. Responsible infectious agents may be mycobacterial, fungal, treponemal, or parasitic organisms, and each case of granulomatous dermatitis should be assessed histochemically for those microbes. In the non-infectious group, examples of necrobiotic or necrotizing granulomas include granuloma annulare; necrobiosis lipoidica; rheumatoid nodule; and lupus miliaris disseminates faciei. Non-necrobiotic/necrotizing and non-infectious lesions are exemplified by sarcoidosis; foreign-body reactions; Melkersson-Rosenthal syndrome; Blau syndrome; elastolytic granuloma; lichenoid and granulomatous dermatitis; interstitial granulomatous dermatitis; cutaneous involvement by Crohn disease; granulomatous rosacea; and granulomatous pigmented purpura. Histiocytic dermatitides that do not feature granuloma formation are peculiar reactions to infection, such as cutaneous malakoplakia; leishmaniasis; histoplasmosis; lepromatous leprosy; rhinoscleroma; lymphogranuloma venereum; and granuloma inguinale.

Neurosarcoidosis: a clinical approach to diagnosis and management

Sarcoidosis is a rare but important cause of neurological morbidity, and neurological symptoms often herald the diagnosis. Our understanding of neurosarcoidosis has evolved from early descriptions of a uveoparotid fever to include presentations involving every part of the neural axis. The diagnosis should be suspected in patients with sarcoidosis who develop new neurological symptoms, those presenting with syndromes highly suggestive of neurosarcoidosis, or neuro-inflammatory disease where more common causes have been excluded. Investigation should look for evidence of neuro-inflammation, best achieved by contrast-enhanced brain magnetic resonance imaging and cerebrospinal fluid analysis. Evidence of sarcoidosis outside the nervous system should be sought in search of tissue for biopsy. Skin lesions should be identified and biopsies taken. Chest radiography including high-resolution computed tomography is often informative. In difficult cases, fluorodeoxyglucose positron emission tomography and gallium-67 imaging may identify subclinical disease and a target for biopsy. Symptomatic patients should be treated with corticosteroids, and if clinically indicated other immunosuppressants such as hydroxychloroquine, azathioprine, cyclophosphamide or methotrexate should be added. Anti-tumour necrosis factor alpha therapies may be considered in refractory disease but caution should be exercised as there is evidence to suggest they may unmask disease.

Animal models of sarcoidosis

Sarcoidosis is a debilitating, inflammatory, multiorgan, granulomatous disease of unknown cause, commonly affecting the lung. In contrast to other chronic lung diseases such as interstitial pulmonary fibrosis or pulmonary arterial hypertension, there is so far no widely accepted or implemented animal model for this disease. This has hampered our insights into the etiology of sarcoidosis, the mechanisms of its pathogenesis, the identification of new biomarkers and diagnostic tools and, last not least, the development and implementation of novel treatment strategies. Over past years, however, a number of new animal models have been described that may provide useful tools to fill these critical knowledge gaps. In this review, we therefore outline the present status quo for animal models of sarcoidosis, comparing their pros and cons with respect to their ability to mimic the etiological, clinical and histological hallmarks of human disease and discuss their applicability for future research. Overall, the recent surge in animal models has markedly expanded our options for translational research; however, given the relative early stage of most animal models for sarcoidosis, appropriate replication of etiological and histological features of clinical disease, reproducibility and usefulness in terms of identification of new therapeutic targets and biomarkers, and testing of new treatments should be prioritized when considering the refinement of existing or the development of new models.

Update on sarcoidosis

PURPOSE OF REVIEW

Sarcoidosis is a multisystem inflammatory disease, characterized by the presence of noncaseating granulomas. Ocular inflammation is often the first manifestation of the disease, and uveitis can be the driving force for treatment. The goal of this review was to provide an update on the relationship between ocular and systemic disease, with a particular focus on cardiac sarcoidosis.

RECENT FINDINGS

Chest radiograph remains the best imaging tool for sarcoidosis, although newer modalities, such as whole-body PET scan, cardiac MRI, and chest computed tomography (CT), may provide additional valuable information in select populations. Ocular sarcoidosis is a marker for vascular endothelial dysfunction and increased arterial rigidity. Choroidal involvement is associated with an increased risk of cardiac disease requiring intervention. Cardiac disease continues to be underdiagnosed in patients with sarcoidosis, although it remains a leading cause of death.

SUMMARY

Sarcoidosis is a systemic disease, and ophthalmologists should continually assess patients for extraocular manifestations. Although no screening guidelines exist, baseline ECGs on asymptomatic patients might identify those at risk for adverse cardiac events. Patients with symptoms of cardiac disease, including palpitations, chest pain, and dyspnea, should have an evaluation by a cardiologist.

Sarcoidosis: a diagnostic challenge in atypical radiologic findings of unilateral lymphadenopathy

Sarcoidosis is a chronic systemic disease with a wide array of clinical findings. Given that the clinical symptoms are not pathognomonic, chest radiographs have become essential to the initial diagnosis and choice of treatment modality. Diagnosis hinges on ruling out alternative diagnoses; sometimes, advanced radiologic techniques and histopathology are required. On this occasion, we present a case of a patient with generalized symptoms, no significant chest radiograph findings and lymphadenopathy where advanced imaging and pathology assisted in the diagnosis.

ProKaSaRe Study Protocol: A Prospective Multicenter Study of Pulmonary Rehabilitation of Patients With Sarcoidosis

Background

Available data assessing the efficacy of pulmonary rehabilitation for patients with chronic sarcoidosis are scant; for Germany, there are none at all.

Objective

To gain information about the benefit of in-house pulmonary rehabilitation for patients with chronic sarcoidosis and for the health care system, we intend to collect data in a prospective multicenter “real-life” cohort trial.

Methods

ProKaSaRe (Prospektive Katamnesestudie Sarkoidose in der pneumologischen Rehabilitation) [Prospective Catamnesis Study of Sarcoidosis in Pulmonary Rehabilitation] will assess a multimodal 3-week inpatient pulmonary rehabilitation program for adult patients with chronic sarcoidosis over a 1-year follow-up time. Defined specific clinical measurements and tests will be performed at the beginning and the end of the rehabilitation. In addition, questionnaires concerning health-related quality of life and the patients’ symptoms will be provided to all patients. Inclusion criteria will be referral to one of the 6 participating pulmonary rehabilitation clinics in Germany for sarcoidosis and age between 18 and 80 years. Patients will only be excluded for a lack of German language skills or the inability to understand and complete the study questionnaires. To rule out seasonal influences, the recruitment will take place over a period of 1 year. In total, at least 121 patients are planned to be included. A descriptive statistical analysis of the data will be performed, including multivariate analyses. The primary outcomes are specific health-related quality of life (St George’s Respiratory Questionnaire) and exercise capacity (6-minute walk test). The secondary outcomes are several routine lung function and laboratory parameters, dyspnea scores and blood gas analysis at rest and during exercise, changes in fatigue, psychological burden, and generic health-related quality of life (36-item Short Form Health Survey).

Results

Funding was obtained on October 12, 2010; enrollment began on January 15, 2011 and was completed by January 14, 2012. Results are anticipated late summer 2015.

Conclusions

Due to the large number of participants, we expect to obtain representative findings concerning the effectiveness of pulmonary rehabilitation for patients with sarcoidosis and to provide a dataset of assessed objective and subjective short- and long-term changes due to pulmonary rehabilitation. The results should form the basis for the planning of a randomized controlled trial.

Trial Registration

German Clinical Trials Register: DRKS00000560; https://drks-neu.uniklinik-freiburg.de/ drks_web/navigate.do?navigationId=trial.HTML&TRIAL_ID=DRKS00000560 (Archived by WebCite® at http://www.webcitation.org/6dKb5X87R)

[Diagnosis and treatment of sarcoidosis. Current standards]

Sarcoidosis is a granulomatous disease that mainly affects the lungs and intrathoracic lymph nodes; however, virtually any organ can be affected. As an orphan disease, recommendations are mainly based on observational or small randomized studies as well as experts' opinion. Diagnosing sarcoidosis requires proof of non-necrotizing granulomas in patients with a compatible symptomatic pattern and the exclusion of other granulomatous diseases. Granulomas can be detected best in the lungs or intrathoracic lymph nodes. Therefore, bronchoscopy and endobronchial ultrasound with biopsies of lymph nodes are the major tools to diagnose sarcoidosis. Frequently, close follow-up and symptomatic therapy are sufficient to allow for spontaneous resolution. In case of functional organ impairment, cardial or CNS involvement, or other complications, steroid therapy is necessary with a starting dose of 0.5 mg/kg body weight that should be tapered-off over 6-12 months. Steroid-refractory disease can be treated by adding methotrexate or azathioprine, two drugs long known in sarcoidosis treatment. Monoclonal antibodies against TNF and lung transplantation are further therapeutic options.