Sarcoidosis: a rheumatologist’s perspective

Abstract

Sarcoidosis is a systemic disorder of unknown etiology, which may involve various tissues and organs and is characterized by a noncaseating granuloma reaction. While pathogenesis is not yet clear, cellular immune system activation and nonspecific inflammatory response occur secondarily to several genetic and environmental factors. T helper 1-cells and macrophage-derived pro-inflammatory cytokines stimulate the inflammatory cascade and formation of granuloma occurs as a result of tissue permeability, cell influx, and local cell proliferation. The different prevalence, clinical results, and disease course observed in different races and ethnic groups, is an indicator of the heterogeneous nature of the disease. Sarcoidosis may mimic and/or may occur concomitantly with numerous primary rheumatic diseases. This disease most commonly presents with bilateral hilar lymphadenopathy, pulmonary infiltrations, and skin and eye lesions. Locomotor system involvement is observed at a range of 15% and 25%. Two major joint involvements have been described: acute and chronic form. The most common form, the acute form, may be the first sign of sarcoidosis and present with arthralgia, arthritis, or periarthritis. Chronic sarcoid arthritis is usually associated with pulmonary parenchymal disease or other organ involvement and occurs rarely. While asymptomatic muscular involvement is reported between 25% and 75%, symptomatic muscular involvement is very rare. Symptomatic myopathy may present as three different types: chronic myopathy, palpable nodular myositis, or acute myositis. Even if rare, 2-5% of cases may exhibit osseous involvement and it is frequently associated with lupus pernio, chronic uveitis, and multisystemic disease. Sarcoidosis was reported together with different rheumatologic diseases. There are studies showing that sarcoidosis may mimic the clinical and laboratory findings of these disorders. Nonsteroidal anti-inflammatory drugs and corticosteroids are used for treating the symptoms of rheumatologic findings. In patients who are unresponsive to corticosteroids, immunosuppressive and anti-tumor necrosis factor alpha drugs may be used. In this review, the incidence of rheumatologic symptoms, the clinical findings, and the treatment of rheumatologic manifestations of sarcoidosis are discussed.

Sternoclavicular joint arthritis as the initial presentation of sarcoidosis

“…Acute arthritis in Löf-gren syndrome is usually oligoarticular, can be polyarticular or rarely, monoarticular (3,5,7). Ankle joint involvement is the most frequent in acute sarcoid arthritis, followed by knee, wrist, and metacarpophalangeal joint involvement (3,8). Axial joint, including costochondral and chondrosternal joints, involvement and sacroiliitis is rare in sarcoidosis (3,4,8).…”

“…Ankle joint involvement is the most frequent in acute sarcoid arthritis, followed by knee, wrist, and metacarpophalangeal joint involvement (3,8). Axial joint, including costochondral and chondrosternal joints, involvement and sacroiliitis is rare in sarcoidosis (3,4,8). However, sternoclavicular joint involvement, to the best of our knowledge, has never been described in sarcoid arthropathy.…”

Sarcoidosis as an Autoimmune Disease

“…The combination of sarcoidosis with Crohn's disease, antiphospholipid syndrome, idiopathic pulmonary fibrosis, and primary biliary cirrhosis is also described (8). When sarcoidosis coexists with ankylosing spondylitis, non-caseating granulomas in the lungs, sacroiliitis, and the HLA-B27 genotype typical for spondyloarthritis are described (9).…”

HTLV‐1 seroprevalance in sarcoidosis. A clinical and laboratory study in northeast of Iran

“…Sarcoidosis is an immune‐mediated disease, which is diagnosed through non calcified granulomas and with a classic antigenic T helper‐1 immune response . Its prevalence varies throughout the world.…”