Respiratory muscle involvement in sarcoidosis

[Pulmonary involvement in idiopathic inflammatory myopathies]

Idiopathic inflammatory myopathies are rare systemic diseases with different types of pulmonary manifestations depending on the underlying aetiology; here, interstitial lung diseases (ILD) are the most frequently found patterns depending on the underlying disorder. There is a lack of sufficient prospective studies on this heterogeneous group of patients, particularly in case of ILD being involved. The diagnosis is based upon guideline recommendations for ILD and requires a multidisciplinary discussion within a team with specific expertise in this field. Myositis specific antibodies and myositis associated antibodies form an essential part of the diagnostic tools and may also be associated with a certain phenotype or disease progression. Anti-t-RNA-synthetase antibodies (Anti-ARS) and anti-melanoma differentiation-associated gene 5 antibodies (MDA5) play an important clinical role for treatment the estimation of response and prognosis. The most common ILD patterns are nonspecific interstitial pneumonia (NSIP) and organising pneumonia (OP) or a mixed pattern of both. Treatment is based on systemic steroids and early initiation of other immunosuppressant drugs. Evidence for this is, however, sparse, since most of the studies having investigated treatment modalities are of retrospective nature, even though some new prospective data may be useful for the establishment of treatment pathways in the future.

Atypical Muscular Sarcoidosis Involvement Revealed by 18F-FDG PET/CT

We present the case of a 65-year-old woman with known pulmonary and muscular sarcoidosis who presented with dyspnea. FDG-PET/CT revealed unsuspected active myositis of multiple muscle groups, including the neck, and was useful in monitoring treatment response.

Muscular sarcoidosis in the eyes of 18 F-FDG PET/CT

PURPOSE

The aim of this study was to determine the frequency, symptoms, activity and pattern of muscle sarcoidosis, correlation with laboratory parameters, and to assess its therapy response with ¹⁸ F-FDG PET/CT.

METHODS

Study included 90 patients with biopsy confirmed sarcoidosis and symptoms/biochemical/imaging findings suggestive of active disease. The exclusion criteria were: presence of cancer or other diseases that resemble sarcoidosis on PET/CT (Wegener syndrome, tuberculosis, aspergillosis), and the glucose level being greater than 11 mmol/L. All patients were screened for muscle sarcoidosis with ¹⁸ F-FDG PET/CT examination. Follow-up examination was done 1 year after the baseline in order to evaluate therapy response.

RESULTS

Disease was very rare and present in only 7/90 patients. Most of the patients had polysymptomatic disease, while muscle pain was less frequent, present only in one-third of the patients. The disease was usually present in the lower limbs, upper limbs, and skeletal striated muscles. The most common pattern of disease was nodular. Disease activity estimated with SUVmax was not in correlation with the ACE findings, creatine kinase, and aldolase levels (p > 0.05). Follow-up PET/CT revealed complete remission in one patient and partial remission in two.

CONCLUSION

¹⁸ F-FDG PET/CT can be useful in asymptomatic young patients with nodular pattern of disease, who have easily relapsing form of disease. It can help in further management of these patients and can affect prognosis of the disease, since most of the laboratory parameters in this entity are within normal limits.

Sarcoidosis involvement of the diaphragm leading to right diaphragmatic elevation: a case report

A 69-year-old male Caucasian presenting with dyspnea on exertion related to unilateral diaphragmatic dysfunction as caused by sarcoidosis is described. First, right diaphragmatic elevation was unexplained, while the patient presented with a restrictive pattern in lung function testing using bodyplethysmography and with reduced global and diaphragmatic respiratory muscle strength as evidenced by respiratory pressures. Subsequently, surgical diaphragm plication was performed, unfortunately, without any clinical improvement. Microscopic examination of diaphragm sections revealed a lymphocytic myositis with granulomatous pleuritis showing multiple non-caseating epithelioid granulomas. Accordingly, a lymphocytic alveolitis (26% lymphocytes) with an elevated CD4/CD8 T cell ratio of 8.0% and elevated serum parameters (neopterin and sIL-2 receptor) were established. Consequently, the diagnosis of pulmonary sarcoidosis with diaphragm involvement but without extrapulmonary involvement has been established. Therefore, sarcoidosis needs to be considered in any patient presenting with unilateral diaphragmatic dysfunction. The optimal treatment strategy, however, needs to be established in the future.

Sarcoidosis

Sarcoidosis is an inflammatory disorder of unknown cause that is characterized by granuloma formation in affected organs, most often in the lungs. Patients frequently suffer from cough, shortness of breath, chest pain and pronounced fatigue and are at risk of developing lung fibrosis or irreversible damage to other organs. The disease develops in genetically predisposed individuals with exposure to an as-yet unknown antigen. Genetic factors affect not only the risk of developing sarcoidosis but also the disease course, which is highly variable and difficult to predict. The typical T cell accumulation, local T cell immune response and granuloma formation in the lungs indicate that the inflammatory response in sarcoidosis is induced by specific antigens, possibly including self-antigens, which is consistent with an autoimmune involvement. Diagnosis can be challenging for clinicians because of the potential for almost any organ to be affected. As the aetiology of sarcoidosis is unknown, no specific treatment and no pathognomic markers exist. Thus, improved biomarkers to determine disease activity and to identify patients at risk of developing fibrosis are needed. Corticosteroids still constitute the first-line treatment, but new treatment strategies, including those targeting quality-of-life issues, are being evaluated and should yield appropriate, personalized and more effective treatments.

Radiologic Manifestations of Musculoskeletal Sarcoidosis

PURPOSE OF REVIEW

The purpose of this review article is to present the spectrum of abnormalities and multi-modality imaging evaluations in patients with musculoskeletal sarcoidosis.

RECENT FINDINGS

The articular manifestations of sarcoidosis are difficult to distinguish from those of the other inflammatory and degenerative arthropathies, and the muscular lesions in sarcoidosis are generally clinically silent and therefore often missed. Magnetic resonance imaging has shown these manifestations to be very common in active sarcoidosis, and should thus be included in the screening if musculoskeletal sarcoidosis is suspected. The clinician should consider magnetic resonance imaging for the evaluation of patients with sarcoidosis who have unexplained osteoarticular complaints if standard radiographs are negative. Furthermore, radiologists should include sarcoidosis in the differential diagnosis of musculoskeletal disease detected at magnetic resonance imaging in the appropriate clinical setting.