Primary Sjögren's syndrome complicated by sarcoidosis and psoriasis vulgaris

Comorbid autoimmune diseases in patients with sarcoidosis: A nationwide case-control study in Taiwan

The association between sarcoidosis and autoimmune comorbidities has been reported, however, it has seldom been confirmed by a large nationwide study. Our study aimed to clarify the association between sarcoidosis and autoimmune comorbidities in the Taiwanese. A total of 1237 patients with sarcoidosis and 4948 age- and sex-matched control subjects were selected from the National Health Insurance Research Database of Taiwan from 1997 to 2010. Multiple logistic regressions were performed to calculate the odds of comorbidities between the two groups. The prevalence of sarcoidosis was 2.17/100 000 individuals in Taiwan. Sarcoidosis patients tended to run a higher risk of autoimmune comorbidities than the control group (17.6% vs 9.4%, P < 0.05). Autoimmune thyroid disease (adjusted odd ratio [aOR], 1.32; 95% confidence interval [CI], 1.05-1.64), Sjögren's syndrome (aOR, 11.6; 95% CI, 4.36-31.0) and ankylosing spondylitis (aOR, 3.80; 95% CI, 2.42-5.97) were significantly associated with sarcoidosis. The sex-stratified analyses were carried out to demonstrate a significant association of sarcoidosis with ankylosing spondylitis in both sexes, but with autoimmune thyroid disease in male patients and with Sjögren's syndrome female patients, respectively. Besides, the diagnosis of the autoimmune comorbidities strongly associated with sarcoidosis tended to be established after that of sarcoidosis. This study demonstrated that patients with sarcoidosis tended to have autoimmune thyroid disease, Sjögren's syndrome and ankylosing spondylitis, and the diagnosis of sarcoidosis usually preceded that of associated comorbidities. Clinicians should be alert to autoimmune comorbidities in patients with sarcoidosis.

Current knowledge on psoriasis and autoimmune diseases

Psoriasis is a prevalent, chronic inflammatory disease of the skin, mediated by crosstalk between epidermal keratinocytes, dermal vascular cells, and immunocytes such as antigen presenting cells (APCs) and T cells. Exclusive cellular “responsibility” for the induction and maintenance of psoriatic plaques has not been clearly defined. Increased proliferation of keratinocytes and endothelial cells in conjunction with APC/T cell/monocyte/macrophage inflammation leads to the distinct epidermal and vascular hyperplasia that is characteristic of lesional psoriatic skin. Despite the identification of numerous susceptibility loci, no single genetic determinant has been identified as responsible for the induction of psoriasis. Thus, numerous other triggers of disease, such as environmental, microbial and complex cellular interactions must also be considered as participants in the development of this multifactorial disease. Recent advances in therapeutics, especially systemic so-called “biologics” have provided new hope for identifying the critical cellular targets that drive psoriasis pathogenesis. Recent recognition of the numerous co-morbidities and other autoimmune disorders associated with psoriasis, including inflammatory bowel disease, multiple sclerosis, rheumatoid arthritis, and systemic lupus erythematosus suggest common signaling elements and cellular mediators may direct disease pathogenesis. In this review, we discuss common cellular pathways and participants that mediate psoriasis and other autoimmune disorders that share these cellular signaling pathways.