Involvement of the liver in rheumatic diseases

Autoimmune Liver Diseases and Rheumatoid Arthritis-Is There an Etiopathogenic Link?

Rheumatoid arthritis (RA) is a systemic immune-mediated disease that, in addition to the articular involvement, can have extra-articular manifestations. Even though liver damage in RA is not very common, associated autoimmune liver diseases (AILDs) may occur. The most common AILD associated with RA is primary biliary cirrhosis (PBC), followed by autoimmune hepatitis (AIH) and primary sclerosing cholangitis (PSC). There are common underlying mechanisms that play a role in the emergence of autoimmunity and inflammation in both rheumatic and autoimmune liver diseases. Genetic studies have revealed the existence of several common disease-associated genes shared between RA and AILDs, and infectious triggers, particularly those associated with recurrent or complicated urinary tract infections, are also speculated to be potential triggers for these conditions. Moreover, these diseases share common serologic patterns characterized by the presence of specific autoantibodies and hyper-gammaglobulinemia. In this study, we focus on reviewing the association between RA and AILDs regarding the prevalence and possible etiopathogenic link.

Rheumatoid arthritis: Extra-articular manifestations and comorbidities

Although synovitis is the pathological hallmark of rheumatoid arthritis (RA), many extra-articular manifestations (EMs) and comorbidities likely occur due to the complex, chronic, inflammatory, and autoimmune features of RA. Cardiovascular (CV) disease is the most common cause of death in patients with RA. Compared to the general population, patients with RA have twice the risk of myocardial infarction and up to 50% increased CV mortality risk. Severe and prolonged disease activity, genetics, and inflammation (e.g. CRP, ACPA, cytokines, matrix-degrading enzymes) play important roles in CV disease and atheroscleroticdamage. The second major cause of death in patients with RA is respiratory disease, which occurs in 30-40% of patients. RA may affect the lung interstitium, airways, and pleurae, while pulmonary vascular involvement is less frequent. Central and peripheral nervous system involvement is usually due to small vessel vasculitis, joint damage, or drug toxicity. There is also evidence that microvascular cerebral damage caused by systemic inflammation is associated with the development of Alzheimer's disease and vascular dementia. Some observational studies have hinted how Disease Modified Anti-Rheumatic Drugs and biologics could reduce the incidence of dementia. Primary gastrointestinal and renal involvements are rare and often relate to drug therapy. To minimize morbidity and mortality, physicians must manage RA disease activity (treat-to-target) and monitor risk factors and concomitant conditions (e.g. smoking cessation; weight regulation; monitoring blood pressure, lipids, thyroid hormone, folic acid and homocysteine; screening for depression, anxiety, atlantoaxial instability, and atherosclerosis). This article aims to provide an overview of the most prevalent and important EMs and comorbidities associated with RA.