Sarcoidosis and Autoimmune Inflammatory Syndrome Induced by Adjuvants

Currently, sarcoidosis remains one of the diseases with unknown etiology, which significantly complicates its diagnosis and treatment. Various causes of sarcoidosis have been studied for many years. Both organic and inorganic trigger factors, provoking the development of granulomatous inflammation are considered. However, the most promising and evidence-based hypothesis is the development of sarcoidosis as an autoimmune disease, provoked by various adjuvants in genetic predisposed individuals. This concept fits into the structure of the autoimmune/inflammatory syndrome, induced by adjuvants (ASIA) that was proposed in 2011 by Professor Shoenfeld Y. In this paper, the authors reveal the presence of major and minor ASIA criteria for sarcoidosis, propose a new concept of the course of sarcoidosis within the framework of ASIA, and point out the difficulties in creating a model of the disease and the selection of therapy. It is obvious that the data obtained not only bring us closer to understanding the nature of sarcoidosis, but also potentiate new studies confirming this hypothesis by obtaining a model of the disease.

Coexistence of immune-mediated diseases in sarcoidosis. Frequency and clinical significance in 1737 patients

OBJECTIVE

To analyze whether immune-mediated diseases (IMDs) occurs in sarcoidosis more commonly than expected in the general population, and how concomitant IMDs influence the clinical presentation of the disease.

METHODS

We searched for coexisting IMDs in patients included in the SARCOGEAS-cohort, a multicenter nationwide database of consecutive patients diagnosed according to the ATS/ESC/WASOG criteria. Comparisons were made considering the presence or absence of IMD clustering, and odds ratios (OR) and their 95% confidence intervals (CI) were calculated as the ratio of observed cases of every IMD in the sarcoidosis cohort to the observed cases in the general population.

RESULTS

Among 1737 patients with sarcoidosis, 283 (16%) patients presented at least one associated IMD. These patients were more commonly female (OR: 1.98, 95% CI: 1.49-2.62) and were diagnosed with sarcoidosis at an older age (49.6 vs. 47.5years, P<0.05). The frequency of IMDs in patients with sarcoidosis was nearly 2-fold higher than the frequency observed in the general population (OR: 1.64, 95% CI: 1.44-1.86). Significant associations were identified in 17 individual IMDs. In comparison with the general population, the IMDs with the strongest strength of association with sarcoidosis (OR>5) were common variable immunodeficiency (CVID) (OR: 431.8), familial Mediterranean fever (OR 33.9), primary biliary cholangitis (OR: 16.57), haemolytic anemia (OR: 12.17), autoimmune hepatitis (OR: 9.01), antiphospholipid syndrome (OR: 8.70), immune thrombocytopenia (OR: 8.43), Sjögren syndrome (OR: 6.98), systemic sclerosis (OR: 5.71), ankylosing spondylitis (OR: 5.49), IgA deficiency (OR: 5.07) and psoriatic arthritis (OR: 5.06). Sex-adjusted ORs were considerably higher than crude ORs for eosinophilic digestive disease in women, and for immune thrombocytopenia, systemic sclerosis and autoimmune hepatitis in men.

CONCLUSION

We found coexisting IMDs in 1 out of 6 patients with sarcoidosis. The strongest associations were found for immunodeficiencies and some systemic, rheumatic, hepatic and hematological autoimmune diseases.

Spondyloarthritis and sarcoidosis: Related or fake friends? A systematic literature review

BACKGROUND

Sarcoidosis and spondyloarthritis (SpA) have been regularly associated. Bone iliac granulomas have also been described. We propose herein a systematic review of rheumatologic axial manifestations of sarcoidosis.

METHODS

PubMed and the Cochrane Library were used to conduct this systematic literature review. Case reports and cross-sectional studies were reviewed according to Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines.

RESULTS

A total of 41 articles were eligible. Three cross-sectional studies on the association between SpA and sarcoidosis showed a prevalence of sacroiliitis and SpA ranging from 12.9 to 44.8% and 12.9 to 48.3% in inflammatory back pain (IBP) subgroups, respectively. However, the IBP definitions and sacroiliac joint (SIJ) imaging modalities (X-rays or magnetic resonance imaging) were heterogeneous, and X-ray was mainly used for sacroiliitis diagnosis (in 78% of cases). Thirty-one case-report articles of the sarcoidosis-sacroiliitis association were identified, representing 35 patients. ASAS criteria for SpA were met in half of cases (16/32) and 46% (12/26) had HLA B27 positivity. Sarcoidosis occurred after sacroiliac symptoms in 47% of cases. In the seven case-report articles with granulomatous sacroiliac bone involvement, unilateral involvement seemed higher than in the sarcoidosis-sacroiliitis group.

CONCLUSION

Literature analysis found a good evidence of the association between SpA and sarcoidosis, and special attention should be given to patients reporting IBP. Unilateral sacroiliitis may raise suspicion of granulomatous bone involvement, distinct from sacroiliitis. Imaging modalities used to study the SIJ in patients with sarcoidosis have been heterogeneous and further investigation is needed.